steel connections software program cse: text of multimedia

CONNECTION STUDY ENVIRONMENT

CSE ONLINE LESSONS

TEXT

http://www.steelchecks.com

Via Pinturicchio, 24

20133 Milan - Italy

[email protected]

Copyright © 2000-2012 – Castalia s.r.l.

Rev.3 April, 6, 2012 – CSE Version 4.43

http://www.steelchecks.com/

mailto:[email protected]

CSE: texts of the online movie lessons ©2001-2012 Castalia s.r.l. www.steelchecks.com [email protected]

Pagina vuota

CSE movie lessons may be freely downloaded here:

http://www.steelchecks.com/PRO/CS/lessons.asp

Note well: there could be some slight differences between the online movie lessons and the

text printed here, as the developping effort never stops and the program is continuously

upgraded. In case of difference, please look at the program guide, which is always updated to

the latest version of the program.

NOTE PER LA PRODUZIONE E LA STAMPA

- Prima di creare il pdf, fare una copia di questo documento ed eliminare eventuali lezioni mancanti (segnalate

con ###) Nome file: Steel-connections-lessons.pdf

- Non stampare i caratteri nascosti (strumenti-opzioni-stampa).

- Aggiornare data e numero dei prenodi dell’archivio nei filmati 006 e 008.

- Aggiornare revisione e versione in copertina.

http://www.steelchecks.com/PRO/CS/lessons.asp

CSE: texts of the online movie lessons ©2001-2012 Castalia s.r.l. www.steelchecks.com [email protected] 5

SUMMARY

001 OVERVIEW: The CSE Project ................................................................................... 11

006 OVERVIEW: Node library (last updated on ________ 20__ ) .................................. 15

007 OVERVIEW: Creating a node using the Light version ............................................... 16

008 OVERVIEW: Recording and reassigning a PRenode ................................................. 20

010 TOUR – Importing from the FEM – First steps .......................................................... 27

011 TOUR – Base plate ...................................................................................................... 30

012 TOUR – Flanged splice joint ....................................................................................... 34

013 TOUR – Flanged beam-column joint .......................................................................... 38

014 TOUR – Beam-beam joint with angle bracket ............................................................ 41

015 TOUR – Bracing node ................................................................................................. 44

019 TOUR – CSE as a stand-alone program ...................................................................... 46

020 TOUR – Beam-column joint (angle bracket)............................................................... 49

021 TOUR – Beam-beam joint (welded) ............................................................................ 51

022 TOUR – Splice joint (flanged) ..................................................................................... 53

030 TOUR – Non-typical joints .......................................................................................... 54

100 WORKFLOW STAGES: the FULL version vs the LIGHT version ........................... 57

101 FULL Stage 1a: importing the FEM model ................................................................. 60

102 FULL Stage 1b: manually creating or modifying the FEM model .............................. 62

103 FULL Stage 1c: automatically creating the FEM model ............................................. 63

105 FULL Stage 2: searching for members ........................................................................ 65

110 FULL Stage 3: searching for JNodes ........................................................................... 66

120 FULL Stage 4a: manually creating the Renode from scratch ...................................... 69

130 FULL Stage 4b: creating the Renode automatically or semi-automatically ................ 71

140 FULL Stage 5: setting up the checks ........................................................................... 73

145 FULL Stage 6: running the checks and analysing the results ...................................... 76

150 LIGHT Stage 1a: importing the model, searching for JNodes .................................... 78


151 LIGHT Stage 1b: automatically creating the model for an individual node ................ 79

160 LIGHT Stage 2: constructing the Renode .................................................................... 80

165 LIGHT Stage 3: modifying the Renode constructed ................................................... 82

170 LIGHT Stage 4: setting up the checks ......................................................................... 83

180 LIGHT Stage 5: running the checks and analysing the results .................................... 84

200 TERMINOLOGY: Nodes, JNodes and Renodes......................................................... 85

201 TERMINOLOGY: Classification of JNodes ............................................................... 87

202 TERMINOLOGY: Joined members, joiners, force transferrers, and stiffeners .......... 88

203 TERMINOLOGY: Stiffeners vs force transferrers ...................................................... 89

204 TERMINOLOGY: Rigid or elastic attachments .......................................................... 90

205 TERMINOLOGY: Bearing support ............................................................................ 91

207 TERMINOLOGY: Predefined variable ....................................................................... 92

208 TERMINOLOGY: User variable ................................................................................. 93

209 TERMINOLOGY: User checks ................................................................................... 94

301 TOPICS: Modelling the objects in CSE ...................................................................... 97

302 TOPICS: Representing joiners in CSE ........................................................................ 99

303 TOPICS: Identifying objects in CSE ......................................................................... 100

304 TOPICS: Connection ................................................................................................. 102

305 TOPICS: Chains......................................................................................................... 105

306 TOPICS: Renode coherence ...................................................................................... 107

307 TOPICS: Overlaps ..................................................................................................... 108

308 TOPICS: Work processes .......................................................................................... 109

310 TOPICS: Bolt layouts ................................................................................................ 110

320 TOPICS: Weld layouts .............................................................................................. 112

330 TOPICS: Internal forces needed for checking ........................................................... 113

331 TOPICS: Dummy combinations, user combinations and FEM combinations .......... 115

333 TOPICS: Member net-sections checks ...................................................................... 117


334 TOPICS: Simplified force-transferrers checks .......................................................... 118

335 TOPICS: User checks ................................................................................................ 119

336 TOPICS: Block-tear checks ....................................................................................... 120

350 TOPICS: Bolt-layout checks...................................................................................... 121

360 TOPICS: Weld-layout checks .................................................................................... 122

370 TOPICS: Displacement checks .................................................................................. 123

380 TOPICS: Standard checks.......................................................................................... 124

390 TOPICS: Connection codes in the FEM model ......................................................... 125

400 INTERFACE: Overview ............................................................................................ 127

401 INTERFACE: Views ................................................................................................. 129

402 INTERFACE: Buttons ............................................................................................... 131

500 MENU: Overview ...................................................................................................... 135

501 MENU: File ............................................................................................................... 138

502 MENU: Modify .......................................................................................................... 140

503 MENU: Display ......................................................................................................... 141

504 MENU: Draw ............................................................................................................. 143

505 MENU: Enquire ......................................................................................................... 145

506 MENU: Fem............................................................................................................... 147

507 MENU: Jnodes ........................................................................................................... 149

508 MENU: Renode ......................................................................................................... 150

509 MENU: Checks .......................................................................................................... 151

510 MENU: Window and Help ........................................................................................ 152

511 MENU: Prenode......................................................................................................... 153

512 MENU: Nodes (light version) .................................................................................... 155

600 COMMANDS: FILE – IMPORT FEM MODEL, UPDATE FEM MODEL ............ 157

610 COMMANDS: MODIFY – UNITS .......................................................................... 160

611 COMMANDS: MODIFY – SELECT ....................................................................... 161


612 COMMANDS: MODIFY – SETTINGS ................................................................... 163

620 COMMANDS: DISPLAY – ORIENTATION .......................................................... 165

621 COMMANDS: DISPLAY – MODES ....................................................................... 167

622 COMMANDS: DISPLAY – OBJECTS .................................................................... 169

623 COMMANDS: DISPLAY – SCENE POINTS ......................................................... 170

630 COMMANDS: ENQUIRE – NET SECTIONS ........................................................ 172

640 COMMANDS: FEM – NODES ................................................................................ 174

641 COMMANDS: FEM – ELEMENTS – PART 1 OF 3 .............................................. 175



645 COMMANDS: FEM – TYPICAL NODES .............................................................. 185

650 COMMANDS: FEM – ASSIGN CONSTRAINT ..................................................... 188

651 COMMANDS: FEM – ASSIGN END RELEASE ................................................... 190

652 COMMANDS: FEM – SEARCH MEMBERS ......................................................... 193

660 COMMANDS: JNODES – SEARCH ....................................................................... 195

661 COMMANDS: JNODES – EDIT .............................................................................. 198

662 COMMANDS: JNODES – EXTRACT MEMBERS ................................................ 201

664 COMMANDS: JNODES – CREATE LISTING, OPEN LISTING .......................... 203

670 COMMANDS: RENODE – SET CURRENT ORIENTATION ............................... 205

671 COMMANDS: RENODE – TRIM-EXTEND MEMBER ........................................ 207

672 COMMANDS: RENODE – MODIFY MEMBER.................................................... 210

673A COMMANDS: RENODE – ADD “THROUGH” (CLEAT/FORCE

TRANSFERRER) .................................................................................................................. 212

673B COMMANDS: RENODE – ADD “THROUGH” (CLEAT/FORCE

TRANSFERRER) – PART 2 ................................................................................................. 214

674 COMMANDS: RENODE – ADD WELD LAYOUT ............................................... 218

675 COMMANDS: RENODE – ADD BOLT LAYOUT ................................................ 222

676 COMMANDS: RENODE – ADD BOLT LAYOUT (DIALOG BOX) .................... 225


680 COMMANDS: RENODE –DELETE COMPONENTS ........................................... 235

681 COMMANDS: RENODE – MODIFY COMPONENT ............................................ 236

682 COMMANDS: RENODE – COPY-RECOPY COMPONENTS .............................. 237

683 COMMANDS: RENODE – ROTATE COMPONENTS .......................................... 240

684 COMMANDS: RENODE – MODIFY BOLT LAYOUT SETTINGS ..................... 241

685 COMMANDS: RENODE – SHIFT COMPONENTS .............................................. 242

686 COMMANDS: RENODE – WORK PROCESSES .................................................. 244

689 COMMANDS: RENODE – ADD VARIABLE ........................................................ 249

690 COMMANDS: RENODE – ADD CONDITION ...................................................... 251

691 COMMANDS: RENODE – MODIFY VARIABLE OR CONDITION ................... 254

692 COMMANDS: RENODE – DELETE VARIABLE OR CONDITION.................... 255

695 COMMANDS: RENODE – CHECK OVERLAPS .................................................. 256

696 COMMANDS: RENODE – CHECK COHERENCE ............................................... 257

697 COMMANDS: RENODE – EXPORT DXF ............................................................. 258

698 COMMANDS: RENODE – ASSIGN PRENODE .................................................... 259

700 COMMANDS: CHECKS – SET UP ......................................................................... 263

701 COMMANDS: CHECKS – CHECK RENODE ....................................................... 266

702 COMMANDS: CHECKS –ENVELOPE, CURRENT RESULTS, ENQUIRE ........ 268

704 COMMANDS: CHECKS – DISPLAY BEARING-SURFACE RESULTS ............. 270

705 COMMANDS: CHECKS – DISPLAY NET SECTION RESULTS ........................ 272

706 COMMANDS: CHECKS – DISPLAY FORCES ..................................................... 274

707 COMMANDS: CHECKS – DISPLAY COMPONENT FEM RESULTS ................ 276

708 COMMANDS: CHECKS – DEFORMED VIEW, DEFORMED SCALE ............... 280

709 COMMANDS: CHECKS – COMBINATIONS, INSTANCES ............................... 281

710 COMMANDS: CHECKS – OPEN LISTING ........................................................... 284

730 COMMANDS: PRENODE – NEW, SAVE .............................................................. 290

731 COMMANDS: PRENODE – RESTART .................................................................. 293


733 COMMANDS: PRENODE – ADD IMAGE ............................................................. 295

735 COMMANDS: PRENODE – PAUSE, CONTINUE, ABORT ................................. 296

739 COMMANDS: PRENODE – ARCHIVE .................................................................. 297

801 PROBLEMS: Bearing support – Bearing surface ..................................................... 299

802 PROBLEMS: Bearing support – constitutive law for the bearing support ................ 313

805 PROBLEMS: Shear-only bolts .................................................................................. 318

810 PROBLEMS: Flexibility index for bolt layouts ........................................................ 320

820 PROBLEMS: Checking stiffeners ............................................................................. 322

825 PROBLEMS: FEM modelling – general remarks ..................................................... 323

826 PROBLEMS: FEM modelling – linear vs non-linear ................................................ 325

830 PROBLEMS: Selecting your checks and how to run them ....................................... 327

840 PROBLEMS: Parameterizing Renodes ..................................................................... 329

901 Defining a node with the light version ....................................................................... 331


001 OVERVIEW: The CSE Project

[vista interfaccia con renodo complesso]

CSE is a software package dedicated to computing and designing connections between

structural elements. Although it currently supports only steel elements, it can also be

generalised to compute connections between elements made of wood or other materials. The

software is being continually developed, and future enhancements are likely to include

support for elements made of different materials.

[vista di un Renodo molto strano]

Designing and checking connections is a very complex and scarcely automated field, given

the extremely complex and general nature of the problems involved. CSE was created as a

widely applicable tool for designing and checking connections, and as such, it has provided

innovative solutions to some very difficult problems.

The CSE project is the fruit of many years of research and development, carried out using

wholly original methodologies. Originally offered as a tool for specialists, it is also available

from 2012 in a simplified, cut-down form (the LIGHT version), aimed at less advanced

designers.

Further enhancements are in the pipeline – to cater for connections between wooden

elements, for example – and the intention over the next five or ten years is to extend its


already wide range of functionality to handle increasingly complex connections in an

increasingly swift, safe and comprehensive way.

In studying the connections, we have had to solve numerous previously undocumented

problems and introduce specific new terminology; it is advisable to become familiar with this

in order to use the software effectively.

The main challenge in developing the program – as well as its greatest merit – is the

generality of the approach taken to the problem of the connections, which used to be handled

in terms of families of similar elementary connections (home recipes). CSE, however,

tackles even complex and unusual connections using general analysis methodologies.


This is what makes the FULL version a unique tool for steel-structure specialists worldwide.

Indeed, the CSE user interface is available in English as well as in Italian, with a highly

comprehensive documentation set – including multimedia content – in both languages. This

makes the research and development effort invested in CSE accessible to experts all over the

planet.

The LIGHT version offers complete, general functionality with enhanced ease of use

compared to the FULL version. It has been specially designed for junior designers and their

senior colleagues who often deal with standard (or standardisable) nodes.


The LIGHT version uses a library of standard connections that the FULL version can add to

and extend: this means that personalised archives can be created for an individual user, thus

speeding up the process of analysing and computing the connections.

[immagini varie pre e post]

With all the man-years of work that have gone into it, CSE can now be considered one of the

most advanced and general tools in the world for studying and analysing connections.


006 OVERVIEW: Node library (last updated on ________ 20__ )

trascrizione/revisione: gennaio 2012

[modello vuoto]

This video presents the 169 parametric nodes available in CSE version 4.43, released

in February 2012.

As the node library is regularly extended, more nodes may now be available than

those shown here.

Now let’s take a look at all the nodes in the archive. These nodes are parameterised,

and the user can modify their parameters when applying them. Note that users of the FULL

version can build their own nodes and save them into the archive.

[aprire l’archivio e scorrere i nodi, lasciando circa 3 secondi per ogni nodo]


007 OVERVIEW: Creating a node using the Light version


In this video, we will see how to create a node using the LIGHT version of CSE. This

node will be built by creating a simple FEM model describing the topology and orientation of

the members, and then automatically constructing the node by choosing one of the available

solutions from a node library.

Using the command to add standard structures [click], we select a simple beam-

column joint from the various templates available. Member number 1 (in red) is the column;

member number 2 (in black) is the beam. [click primo schema trave-colonna]

We assign a material to the two members, [click]e.g. S275. [applica]

We select an HEB section from the archive [click], e.g. 200, [click] and we assign it to

member number 1 (the column). [assegna] Returning to the archive, we select an IPE

section, e.g. 220 [click], and we assign it to member number 2 (the beam). [assegna]

We leave the strong axis as the axis, WITHOUT introducing a hinge at the end of the

beam. This will therefore be a clamped node.

We click OK. [click] The system prompts us to save the model, [salva]then a three-

dimensional node is created for us to work on. This node has not yet been constructed. To do

so, in the LIGHT version, we browse the archive to find the predefined nodes that are suitable

for this type. [click]

In the version of the software used in this video, the program has selected 7 different

nodes as being applicable to our node. Let’s take a look at the various solutions. [scorrere,

fermarsi al primo con le costole] Since this is a clamped joint, we’ll choose a node with

stiffeners. [scorrere fino all’ultimo, tornare sul penultimo]

We browse the images to see how the node will be built. [click] We click OK. [click]


The list of the operations that will enable the node to be built automatically is now

shown. First of all, we click OK and tell the program to build the node with the default

parameters. [ok]

The node has now been built. If, though, we don’t like the result for some reason – if

we want this plate to be thicker, for instance – then we can reset the node, reapply the macro

and tell the system to modify the parameters we want in real time, during the construction

process.

To modify the plate, we need to know what it is called. One way to do this is to

activate the “selected entities” panel, deselect all entities, and select the plate that we want.

[click] The plate is called P1, and its current thickness is 10mm.

We reset the node to go back to the beginning [click], and we reapply the predefined

node. [click, fino a lista]

Now, in the list of operations, we un-tick the addition of plate P1, to say that we want

to edit its parameters. [via spunta, clicca OK]

These are the parameter settings for this plate. In particular, the thickness is defined as

a function of the thickness of member 2’s flange (m2.tf). This is the formula that gave us the

10mm value that we saw before. We can edit the formula by inserting multiplication factors

or additive terms, or entering a number, such as 11, which is the thickness we want. [digitare

11]

We click OK [click], and the construction of the node is now complete, with its newly

thickened plate. [pausa] Indeed, we can see that plate P1 is now 11mm thick. [pezzi

selezionati, ecc.]

If we select a node that has already been parameterised, we can still change its

parameters in order to build the nodes that we want, given the type selected.


Now we are ready to run the checks. First of all, we need to decide if the default

settings for checking the elements are suitable in this case.

For example, let’s select plate P1 only [click] and modify it using button “Sel C”

(which stands for “selected component”). [click] We can see that, for example, automatic

FEM modelling is not selected for this plate. We’ll leave these settings as they are [OK] and

consider the general settings for the checks. [set chk]

Eurocode is set, ... and a series of options is available to select only the checks that we

want to perform.

This section is used to specify the combinations with the internal forces to be used to

check the node.

In the LIGHT version, we can add the combinations as a table [click] by pasting the

combinations from Excel tables or by typing the data in manually. [inizializza 5 combi, esc]

Alternatively, we can opt to use a suitable fraction of the members’ elastic or plastic limits,

which is what we’ll do now [click]. We select member 2, which is the one that we are

interested in. [m2] Suppose we do not want to compute it under compression[0] nor under

tension; [0] we want the shear to be 0.3 times the elastic limit, along both the pricipal axes;

[0.3, 0.3] there is no torsion; [0] the moment about the strong axis is 0.3 times the elastic

limit [0.3], and the moment about the weak axis is 0. [0]

This is just one of the ways to define the combinations for the checks. We save the

settings. [ok]

And now we run the checks. [click bottone]

When the checks have been completed, a listing is shown with the results (which we

will not discuss here). [scorri, chiudi]

We can look at a colour-coded map of the utilisations [click], which tells us which

components have been successfully verified and which have not. In this case, all the

components have been verified.


If we inspect the weld utilisation [click, interroga], the status bar at the bottom shows

that this weld has a maximum utilisation of 0.995, from the strength check, in combination

26. As will be clear from the documentation, this combination corresponds to the shear

perpendicular to the web in the horizontal beam.

We may assume that these results are acceptable, or we can alter the weld to increase

the safety margin, using the command shown earlier. [seleziona, modifica]

The image shows all the welds; we can select the one we want (in green), by scrolling

with the arrows, and we can adjust its thickness and hence its throat section. [ ^ ^ ]

We can run the checks again to see what difference this has made. [esci]

As we have seen, we have built and verified this node quickly in just a few clicks.

Here we have only looked at the colour-coded map of the utilisation envelope; please

see the dedicated lessons for full details about all the tools available for viewing and

inspecting the results.


008 OVERVIEW: Recording and reassigning a PRenode


[modello vuoto, versione FULL]

In this video, we will see how to create a parametric node, save it in the archive and

then apply it to similar nodes with different section dimensions.

We begin by creating a typical structure [click] for a ground joint [click] with a

hinged column. [click]

We’ll choose S275, for example, as the material [click] and an HEB as the section –

400, say. [click] We assign this section to member 1, which is the only one in this node.

[click]

We click OK, and the system prompts us to save the model. [click, salva] It then asks

us for the initial settings for the checks. We will modify them later, but for now, we will

accept the default values. [click] We are then prompted whether to add a new node: we’ll say

no. [click]

The three-dimensional node has now been created, at present containing just the

member. At this point, we can build the node normally – manually or automatically – but

what we want to do now is to build the node by saving it in parametric form, in order to add it

to the archive for application later. To do this, we use the command to add a new PRenode.

[click]

In the dialog box that appears, we set the PRenode’s name, e.g. “Test”, [digita] the

prefix to use for the associated images, [digita] a description for the node, e.g. “ground node,

shear-only with light compression”; [digita] and finally an explanation. [“prova”]

We click OK [click], and now we’re ready to start building the node.


We can see that we are in recording mode, because there is a red circle in the

graohical view; in addition, the following commands are enabled: save parametric node,

pause, add images, and abort recording.

[in pausa, solo centri delle facce, non visualizzati]

We can begin by adding a base plate. [click]

The plate’s dimensions will be m1.b, i.e. the base of the sectional form for member

number 1, plus 200 millimetres. [digita] The height will be m1.h plus 200 millimetres.

[digita]

For the thickness, instead of typing the formula in directly, we can create it using an

automated tool. []

The list of all available variables [scorrere alla fine] includes m1.tf, i.e. the flange

thickness for member m1. If we double-click, the variable is added into the box above, which

defines a formula. [doppio click]

We could also enter a number in this box, e.g. 12mm [digita], or as we saw earlier, a

formula based on the section’s dimensions. Since this is a hinged node, we’ll define the plate

thickness, for example, as 0.8 times the thickness of the member’s flange. [digita 0.8*m1.tf]

If we want to round up to the nearest whole number, we type “cei”, which stands for ceiling,

and we put the value in brackets. [digita] We thus obtain a number corresponding to 0.8

times the thickness of member 1’s flange, rounded up to the nearest integer. We enter the

formula [click] and save the plate’s parameters. [ok]

In the next dialog box, we orient the plate by aligning its longer side with the height

of the section [click], and we select the centre of the upper face as the point of insertion.

[click]

We click OK [ok] and position the plate where we want it: at the centre of the section.

[click] The ‘click’ sound confirms that the entities are coplanar, without overlaps. [wav

clack]


We add a constraint block under this plate [click]. We define the parameters in terms

of the member, as always. For example: m1.b*3, [digita] m1.h*3 [digita] and m1.h*3.

[digita]

We rotate the block to align it, then we insert it. [ruota, inserisci] We ensure that the

point in the upper centre of the block coincides with the point in the lower centre of the plate.

[click] [wav clack]

Now we add a bolt layout to connect the plate and the constraint block. [deseleziona

tutto, aggiungi bullonatura]

We select the upper face of the plate [click], whereupon this dialog box appears. The

dialog enables the parameters to be set for the bolt layout, although now is not the time to

explain all its functionality. We will see, though, how a parametric bolt layout can be quickly

added.

Instead of using formulae to determine the arrangement automatically, we define a

fixed number of rows and columns: for example, 2 of each. [digita] So the bolt layout will

always be two rows by two columns.

We can define P1.h-100 [digita], for example, as the separation between the rows,

and P1.b-100 as that between the columns. [digita] Thus, the distance between the rows in

the bolt layout equals the height of the plate, P1.h, minus 100 millimetres. As the bolt layout

is centred, there will be 50 millimetres on each side.

As for the rest, we will not specify a centre offset, hence the layout remains centred,

and we can now define how the bolt layout will function and how it will be checked.

This bolt layout will operate primarily on a compression and shear basis, although

there may be some small moments of transport causing the layout to bend slightly. We

un-tick “shear-only bolts”, [click] although we don’t need to use a bearing surface on the

constraint block to resist the bending, for there is no bending. There is only slight

compression, hence it can also be computed by assigning it to the anchor-bolt shafts.

If, on the other hand, we had wanted to use the constraint block as a bearing surface,

then we would have had to select this option [indica] by specifying the non-linear, no-tension

constitutive law for the support, together with the bearing surface.


In this case, we will only use the bolts in a very simple way, exploiting their

resistance to compression and to the slight bending in the bolt layout, while what we are most

interested in is the bolt shafts’ capacity to resist shear. We click OK to apply the bolt layout.

[OK, deseleziona tutto] [wav clack]

Finally, we add a weld between the column and the plate. [click] We select the

member’s end face. [click] This dialog box gives us a free hand to parameterise the weld

using a series of commands and other features. Because we are dealing in this case with a

standard I-section, we will tell the program to automatically add a weld parameterisation that

normally works well. [click] The web welds depend on the thickness of the web plate; the

flange welds, on that of the flange plate. We click OK to add the weld. [ok] [wav clack]

In geometrical terms, the node is now finished. We could now refine how the checks

are made in more detail, but this will be dealt with in other lessons.

What we want to do now is to add some images to this parametric node, to help those

applying it in the future understand more about it.

We will add our first image by saving the current screen [click]; the jpeg file name is

suggested automatically based on the prefix chosen at the start. We save the image [click].

We select plan view [click] and add this image as well. [click, vista iso]

The saved images have been associated with the parametric node, so that later on we

will be able to see how the node has been constructed. We save the parametric node in the

archive. [salva]

We open the archive to check that the parametric node has been added correctly. [apri e

scorri]

We scroll through the available nodes, of which there were about 4.43 when this video

was made in February 2012. [arriva in fondo] At the end of the list, there is the “test” node

that we have just saved. The two images that we have added are now available. [scorri]

The images can be viewed directly in Paint in their original size [click] and can be

modified, if required, by adding captions or other useful information. [esci]


We will now look at how the parametric node that we have saved behaves when we

apply it to a column with a section other than the HEB 400. We open a new model [apri]. As

before, we define a ground joint. [fino a dialogo sez. mat.] We choose a different material,

such as S235 [applica], a column of a different form [click], like HEB 160 [applica], and we

obtain the desired node. [fino a renodo]

We apply a predefined node. [click] CSE only offers us compatible predefined nodes,

including the one we saved earlier, called “test”. We assign it. [click] This list includes all the

operations that will be carried out automatically to build the node. If we like, the ticks can be

removed to modify the parameters for one or more operations. We now apply the node as it

was saved. [ok]

The node was built automatically, using our earlier parameterisation. Now all we need

to do is set the checks [click]. We keep Eurocode, [indica] and let’s say, for example, that we

want to compute the node with the same elastic limits as the member, with compression equal

to 0.3 times the elastic limit, [0.3] no tension, [0] a shear V2 and a shear V3 equal to 0.2

times the corresponding elastic limits, [0.2 0.2] no torsion [0] and no bending moment in

either direction. [0 0]

Here the fractions refer to the elastic limits. We could also use the plastic limits or

define values for the forces, by entering magnitudes for the forces and couples. We can

import combinations from a table and, if the FEM model has been imported, we can use the

FEM model’s combinations of checks, with the internal forces computed.

We leave the other settings as they are and save the settings. [ok]

Now we run the checks. [ok]

When the checks have been completed, the listing is shown – which is not described

in this video. [scorrere, chiudere, chiudere]

We display the utilisation envelope [E] and see that our connection has been verified.


We have also established that the parametric node recorded previously using an HEB

400 section has also been automatically adapted to a different type of section.


010 TOUR – Importing from the FEM – First steps

trascrizione: gennaio 2012

[TOUR.wsr aperto in Sargon]

We have created a finite-element model of a steel structure using one of the software

packages that can interface with CSE. [vista solida, vista unifilare] In this case, we have used

Sargon; please see the program user guide for details of the interfaces available.

The model has load cases and check combinations. It has been solved with a linear

static analysis, and the post-processing results are available. [vista deformata] The finite

elements have also been checked for strength and stability with Sargon’s automatic checker

in accordance with Eurocode 3, part 1-1. [inviluppo sfruttamenti]

The structure has been fully verified; we can therefore pass the model to CSE to

analyse the connections.

Sargon has a command that runs CSE directly and automatically imports the model.

[indica] For now, though, we will open CSE to show the import process from there. [aprire

CSE] We select the FULL version of the program. [FULL]

Starting with a new project, we import the FEM model. [file-importa] Now we will

import the Sargon model that we saw just now, which has file extension wsr. Similarly, we

could import a SAP2000 file in sdb format or a model from any FEM program that supports

the free interchange format with file extension sr3. [click tour.wsr]

In CSE, we have the same model that we saw in Sargon, with all the information

about the geometry, the finite elements, the properties and the connections. The model also

maintains the internal forces for all finite elements, in all checking combinations. These

forces can be used to check the connections.


We move from the FEM view to the jnode view [click], which contains a 1D-model

containing members instead of finite elements. The members, which have been recognised

automatically during importing, may comprise several finite elements. Indeed, CSE

recognises the “physical” joints in the elements, discarding non-structural nodes used in the

modelling process.

Now we search for jnodes. A jnode is a stepping stone between the node in the FEM

model and the three-dimensional node complete with bolts, welds, plates, angles, etc. The

jnode has all the information on the members joined there, the sections and materials, the

orientations, the end releases and the member hierarchies. Jnodes will be discussed in more

detail in the dedicated lessons.

The Jnodes – Search command starts the automatic search for jnodes. [click, ok, ok]

In this structure, 21 different jnodes have been found, which may be repeated several times.

[click] The preliminary settings for the checks need to be specified; we will go into this on

another occasion. [click] For now, we will just set Eurocode 3 as the reference standard,

defining the actions for checking as being those resulting from the combinations in the

imported FEM model. [click]

Each jnode has a mark and colour of its own. If a jnode occurs more than once in the

structure, we say that it has different instances. We only need to construct a single real node

associated with a jnode, and CSE will check it in all combinations and instances. By selecting

an instance of a jnode, we select all its instances. [click]

Using the Jnodes-Edit command [click], we can access all the information about the

jnodes, including the envelope of their internal actions. [seleziona un jnodo, interroga] We

will not discuss these dialog boxes in detail now, as they are covered in dedicated lessons of

their own. [esc, esc]

The above information can be printed off in an output listing. [jnodi – crea, apri, scorri,

chiudi]

By selecting jnodes one by one, we can view, construct and check the associated real

node.


The next videos show some examples of constructing nodes for this structure.

[callouts]


011 TOUR – Base plate

revisione: gennaio 2012

[TOUR.CSE, vista jnodi con AH selezionato, dialogo edita con AH selezionato ed

evidenziato; pannello pezzi selezionati; punti creati ma non mostrati: solo centri delle facce]

This video shows how to create a simple ground connection with a base plate in the

structure seen in the previous video, which discussed importing a FEM model using the

FULL version of CSE and searching for jnodes.

Jnode AH, which we will be working with here, is a simple ground connection involving a

column.

Let’s look at the real node, or renode, associated with jnode AH, which is the only

one currently selected. The jnode occurs several times in the structure, but we only need to

build and check one of its associated renodes. [vai]

At the outset, only the member is present, without connections. We can build the real

node manually by adding the necessary components freely as required, or we can

automatically assign a compatible predefined node, if available in the archive. Let’s take a

quick look at how to assign a predefined node, which involves using the Assign PRenode

command. [click]

This dialog box offers only the predefined nodes that are applicable to the current

node. Without going into details about this functionality, we choose the last connection. [ok]

A list is shown with all the operations that will be performed automatically to

construct the current node based on the chosen predefined node. The predefined nodes are

parameterised, for use with similar nodes of different dimensions. The parameters can be

edited as required when the predefined node is assigned; in this case, we apply it ‘as is’. [ok]

The current node has been constructed based on the chosen predefined node.


The user needs to check that the connection has been constructed correctly. Then, if

nothing needs to be modified or added, we can move on to setting up and running the

automatic checks.

We have mentioned adding components manually to be positioned at the user’s

discretion. We reset the node, bringing it back to its starting state, and we’ll build it manually.

[click]

We insert the base plate. [click] We define the dimensions [450x450x25, OK]. We

can alter the object’s orientation before inserting it in the scene [esempi], then we select the

point where we want to insert it, and we click the point in the scene to which it must

correspond. [click]

As this is a connection with a rigid attachment, we insert the constraint block

simulating the foundation. [clic, valori di default, inserisci]

We insert the weld layout connecting the column to the base plate. [sp. 10]. We

reduce the thickness of the two welds on the web [8mm].

We insert a bolt layout to anchor the base plate. [click] When the face on which the

screws are to lie is selected, CSE automatically recognises the objects to be drilled, according

to their position. We click on the upper face of the plate. [click]

A dialog box appears for the bolt layout parameters to be defined. We choose the bolt

diameter and class. [M24 - 8.8] We specify how the bolts are to be arranged. [3x3, 180,180,

svuota interno] The following types of arrangement are available: regular, staggered, circular

and free.

We will not go into the details of these various bolt layout settings here, as they are

covered in dedicated lessons of their own. In this case, we want the layout to work on a shear

and tension basis [click] and to act as an anchor [click]. The anchor properties need to be

set up in the dialog box provided. […] We also want the tension to be taken by the bolts and

the compression to be absorbed by the plate crushing against the constraint block: hence we

will use a bearing surface. [click]


We define the constitutive law for the material that constitutes the support (in this

case, concrete blocks). [click] Of the four non-linear, no-tension constitutive laws, we select

the parabola-rectangle version and set up its parameters [click, -21.25; -0.002; -0,0035;

1,5; OK].

Finally, we define the bearing surface. [click] Using the controls provided, we can

define one or more bearing surfaces, in line with the standards. The outlines of the various

objects involved can be used to define combinations and intersections of faces with suitable

projecting borders depending on the stiffness of both the surface and the plate. Without going

into details about this dialog box, we specify the bearing surface by using the outline of the

member. To the outline of the member is added a border ‘c’. The width of this border is

computed automatically depending on the existing components. [c con spessore 25, H

orlata] The bearing surface will also be used to assess the support’s resistance to

compression: this check will be performed on the constraint block. [click, OK].

We insert the layout. [click]

We check for overlaps. [compenetrazioni] The objects do not overlap. There is also a

check that we could use to see that the various entities are joined correctly, although CSE

checks this automatically before verifying the connection.

Setting up the checks will be discussed in detail elsewhere. [imposta verifiche] We

will simply select Eurocode and set the checking combinations as those from the imported

FEM model. [click] This dialog box is also used to choose (among the other options) the

settings for the output listing, the safety factors, the checks to be run, and the check on the

component shifts.

Let’s check the connection. [click]

The checks have been completed; the results listing, if requested, is shown

automatically, and now all the post-processing commands have become available. [envelope]

We can now see the utilisation envelope for each component for all combinations and all

instances of the jnode.

A battery of checks has been run: strength checks on the various bolts and fillet welds;

pull-out checks on the anchor bolts; a compression check on the concrete block; bearing

stress, punching and block-tear checks on the objects pierced by bolts; simplified resistance

checks for the components.


Besides these checks, the system can also automatically create FEM models of the

components and solve them; CSE has linear and non-linear solvers, and other FEM programs

can be used where an interface is available. Users can also add new checking criteria of their

own for the system to run automatically.

Besides the utilisation envelope with the maximum utilisation, its cause, and the

conditions in which it occurs. The following results can be displayed: the deformed views for

the connection in the various combinations and instances; the forces transmitted between the

various entities; the results for the net sections and for the bearing surfaces, etc.

We can display the envelope of the coefficients of utilisation for different combinations.

[click]

As well as colour-coded maps, there are also deformed views, block-tearing failure

paths, results for the bearing surfaces and for the members’ net sections, the forces

transmitted between the various components, stress analyses for the automatic FEM models,

and more. For more on these aspects, please see the other lessons dedicated to them.


012 TOUR – Flanged splice joint


[TOUR.CSE, vista jnodi con AK selezionato, dialogo edita con AK selezionato ed evidenziato, crea

solo centri delle facce]

This video shows how to create a column-column flanged splice joint in the structure

that we saw in video 10, which discussed importing a FEM model into CSE and searching for

jnodes.

We will work with jnode AK, which is hierarchic and does not contain attachments.

Let’s look at the renode associated with jnode AK, which is the only one currently

selected. The jnode occurs several times in the structure, but we only need to build and check

one of its associated renodes. [vai]

Initially, only the members are present, which here are in contact, because no rigid

offsets have been defined in the FEM model. First of all, we shorten the slave member to

create the space to insert the plates. [accorcia di -60mm]

We insert the first plate. [click… 400x400x30, OK]

We select the point of insertion and click on the point to which it must correspond in

the scene. [click]

We obtain the second plate by copying the first one. […]

Now we apply the weld layouts. [click]

We apply 10mm-thick welds to the various edges of the member’s terminal section.

[click]


We adjust the thickness of the welds on the web [8mm] and then insert the layout. [OK]

We apply another weld layout to the other member. […]

Finally, we add a bolt layout to join the two plates. When the face on which the

screws are to lie is selected, CSE automatically recognises the objects to be drilled, according

to their position. [click]

We choose the bolt diameter and class. [M24 – 8.8]

We define the arrangement. [regolare 2x2, 320, 320]

We want the bolts to work on a shear and tension basis. [togliere spunta] We also

want to evaluate the compression on one of the two plates. So we use a bearing-surface

polygon. [spunta]

We define the constitutive law for the support material. [click] From the four non-

linear no-tension laws, we will use the unlimitedly elastic law, specifying a homogenization

factor for the bolts’ modulus and a suitable maximum sigma value, in the current units. [1, 4

(con callout)] The maximum sigma value was obtained by considering the pressure that

would cause the yield stress to be reached in certain critical parts of the plate, as shown in the

pop-up. [ok] We select the bearing surface. [click] To keep things simple, we allow

compression to occur all over the plate’s surface. [click] As seen in the previous video, CSE

enables bearing surfaces to be defined more accurately, in accordance with the standard. We

also define the object whose bearing surface will be checked. [click, OK]

We apply the layout. [click]

We check the connection for consistency and for overlaps. [compenet.] The objects do

not overlap. [coerenza] All the components are connected correctly; so the only chain present

in this case is shown – this is the only possible path between one member and the other.


We modify the upper plate and tell the software to automatically create the FEM

model. [click , spunta] We keep the default parameters for the mesh properties. [ok]

We set up the checks, without going into the details. [click] This dialog box is used to

choose (among the other options) the reference standard, the safety factors, the methods of

computing the internal forces, the checks to run, and the check on the component shifts. We

select Eurocode [click], and we set the checking combinations as those from the imported

FEM model. [click] There are 48 combinations for each of the 16 instances of this node, so in

order to expedite the computation, we ask the system to pre-select the combinations that

maximise the internal forces. Forces acting at the same time (in the set of all combinations)

will also be considered to do so in this pre-selected subset of the combinations. We want the

FEM model of the plate to be created and analyzed automatically. [click, OK]

Let’s check the connection. [click] [durante la creazione del modello fem:] The

FEM model of the plate is created automatically, as requested … [attendere] now the static

analysis on the model is automatically performed…[attendere]


automatically, and now all the post-processing commands are available to analyse the results.

The bolts and welds, in particular, have been checked in the various combinations and

instances. One thing we can do is compare the plate checked using the FEM model and the

one that underwent the bearing-surface check.

[inviluppo] As can be seen from the envelope, in this case for the compressed connection, the

maximum utilisation given by the bearing-surface check is comparable to that from the

analysis of a sophisticated FEM model that includes the state of stress in the plate based on

the forces transmitted by the bolts, the welds and the bearing surface. Let’s look at the current

results [click]; we can go to combination 2, for example [vai a combi 2]. If we inspect the

utilisations, we see that the values for the two plates are very similar, even though they come

from different checks. [interroga] Moving to another combination – number 7, for instance –

we can inspect the utilisations again. [combi 7, interroga]

Let’s now look at the FEM model created automatically for Sargon by CSE, which we

access directly using the command provided. [click] Since we asked CSE to automatically

analyse the model, the post-processing commands are now available. We can look at the Von


Mises stresses in combination 7. [combi 7, von mises faccia visibile] The ratio between the

maximum Von Mises stress and the yield stress is equal to the utilisation value that we saw

earlier in CSE. [aprire la calcolatrice, 191 / 235 = 0.813]


013 TOUR – Flanged beam-column joint


[TOUR.CSE, vista jnodi con AA selezionato, dialogo edita con AA selezionato ed evidenziato,

pannello pezzi selezionati]

This video shows how to create a flanged beam-column joint in the structure shown in

video 10, which discussed importing a FEM model into CSE and searching for jnodes.

Jnode AA, which we will consider here, is hierarchic and has no attachments.

Let’s look at the renode associated with jnode AA, which is the only one currently



Initially only the members are present, and because no offsets had been defined in the

FEM model for one of the two beams, this one overlaps the column; we will now trim it, and

CSE will automatically add the necessary moments of transport into the computation. [-

148mm]

We add the flange. [mostra punti: centro faccia, dimensioni 360x260x18]

We weld the beam to the plate. [sp. 10mm]

We apply the bolt layout. When the face on which the screws are to lie is selected,

CSE automatically recognises the objects to be drilled, according to their position. [click] We

choose the bolt diameter and class, and we specify how they are arranged. [M16 – 8.8, 3x2;

100, 160] We want the bolts to work on a shear and tension basis. [togliere spunta] We insert

the layout. [OK]


We now add the first stiffener to the column. [colonna selezionata; sp. 20, applicata

in basso] We move it into position [z=815mm]. If we do not yet know the precise distance,

we can inspect the distances between the significant points desired. [callout su bottoni

“mostra punti” e “interroga geometria”]

We add the weld layouts to connect the stiffener to the column. […]

Now we select the stiffener and the weld layouts, and we create a copy of them.

[z=+350mm]

We select both the stiffeners, with all the weld layouts, creating copies of them on the

other side of the column. [membratura + angolo; far vedere gli oggetti, isometrica]

We now insert the plate to which we will bolt the second beam’s web; its connection

to the column will not be flanged. [click 330x250x10, inserita già nella posizione giusta]

We weld the plate to the stiffeners and to the member’s web [2 layout da 2 cordoni

ciascuno: sp. 10, l=120, pos.= + - 62 + 1 layout su colonna sp.10, dist=0]

We add the bolt layout to join the plate to the web of the beam. [click]; [3x1,M16

d100, dx= -62.5]

We check the connection for consistency. [coerenza] All the components are

connected correctly; next, the chains are shown – these are the possible paths between the

slave members and their master.

The settings for the checks have already been specified[click veloce]. This dialog box

is used to choose (among the other options) the reference standard, the safety factors, the

methods of computing the internal forces, the checks to run, and the check on the component

shifts.





[Mostrare inviluppo] We can now see the utilisation envelope for each entity, for all

combinations and instances. A battery of checks has been run: strength checks on the various

bolts and welds; bearing stress checks on all the objects pierced by bolts; and the checks on

the net sections of the members with a reduced gross area.

For this connection, we have not checked the compression between the plate and the

column flange, nor have the entities been checked using automatically created FEM models.

For both these aspects, please see the previous video.


014 TOUR – Beam-beam joint with angle bracket


[TOUR.CSE, vista jnodi con AC selezionato, dialogo edita con AC selezionato ed

evidenziato]

This video shows how to create a beam-beam joint with angle brackets in the structure

seen in video 10, which discussed importing a FEM model into CSE and searching for

jnodes.

Jnode AC, which we will consider here, is hierarchic and does not contain attachments.

Let’s look at the renode associated with jnode AC, which is the only one currently



Initially, only the members are present, and since the FEM model has no axial offset

defined for the secondary beam, this overlaps the main one. The secondary beam does,

though, have an offset that brings its upper edge to the same height as the main beam. [vista

x, poi iso]

In the previous videos, we saw how to build a node manually the way we want it. We

will now look at how to apply a predefined node from the archive and modify its parameters.

[click assegna Prenodo]

Only the parametric nodes compatible with the current node are shown. We select the

third-to-last node, which involves an angle-bracket connection with the same offset as the

secondary beam [click immagini, ecc., OK]

We will come back to this dialog box later to modify some of the parameters for this

connection in real time. For now, we apply it ‘as is’. [ok]


The system warns us about a member of the current node being shifted, as CSE

considers the additional moments of transport. Since the offset was already there in the FEM

model, the shifts in the node are null and the message is irrelevant, as the offset had already

been taken into account in solving the FEM model.

Now the connection is finished. We check the connection for consistency and for

overlaps. [compenetrazioni] There are no overlaps. [coerenza] The chains are listed, i.e. the

possible paths from a slave member to the master member: all the entities are therefore

correctly connected.

We set up the checks, without going into the details. [click] This dialog box is used to

choose (among the other options) the reference standard, the safety factors, the methods of

computing the internal forces, the checks to run, and the check on the component shifts. We

select Eurocode [click], and we set the checking combinations as those from the imported

FEM model. [click]

Now we run the checks. [click]

The listing showing the results of the checks, if requested in the settings, is shown

automatically, and now the post processing is available.

We can display the utilisation envelope for all the node’s different combinations and

instances. [click] The utilisations are not very high.

We will not discuss the other tools for analysing the results here in detail, as they are

covered in other lessons. What we will do is reapply the predefined node with changes to

some of its parameters, and see how this will affect the results.

We reset the node and reapply the same predefined node that we used before. [no

inviluppo, azzera, applica lo stesso prenodo]

In the list of operations, we un-tick the addition of bolt layout B1. We can thus amend

its parameters during automatic construction. [OK]

The construction process pauses at the point of adding the bolt layout, and we can (for

example) replace the parametric formula that optimises the computation of the number of


columns with the number 1, forcing B1 to have a single column. [digitare 1] We save the

change, without looking at the parameter settings in detail, as they are covered in other

lessons. [OK]

The node now reflects the modifications that we have made; since the other bolt

layouts were parameterised as a function of the first one, they too now have just a single

column.

We run the checks again [click] and show the envelope. [click]

With fewer bolts, the utilisations are now higher.


015 TOUR – Bracing node


[TOUR.CSE, vista jnodi con AQ selezionato, dialogo edita con AQ selezionato ed

evidenziato]

This video shows how to create a bracing node for the structure seen in video 10,

which discussed importing a FEM model into CSE and searching for jnodes.

Jnode AQ, which we will consider here, is hierarchic and has no attachments.

Let’s look at the renode associated with jnode AQ, which is the only one currently



Initially, only the members are present; because no rigid offsets have been defined in

the FEM model, here the two bracings and the beam overlap. We trim the bracings. We work

out how much to trim them by. [vista +x, mostra punti medi e punti equisp. di 20mm,

interroga; -230mm]

We can select the most convenient view for inserting the plate to be welded to the

main beam. [estrai trave, mostra punti al centro delle facce, vista dal basso].

We insert a rectangular plate. [click, 600x250x20, orientazione +x, +y, +z, ins., uscire

dall’estrazione]

Now we add a weld layout to connect the plate to the beam. [sp.10mm, ins… vista iso]

Next, we add the first bolt layout to fix a bracing to the plate. When the face on which

the screws are to lie is selected, CSE automatically recognises the objects to be drilled,


according to their position. [click; M16 – 8.8, 2x1, 80mm, dy=276mm scorrendo con le

frecce; solo a taglio, inserisci]

We add the second layout to connect the other bracing. [click]

We check the connection for consistency and for overlaps. [compenetrazioni] The

objects do not overlap. [coerenza] All the components are connected correctly; next, the

chains are shown – these are the possible paths between the slave members and their master.

The settings for the checks have already been specified[click veloce]. This dialog box

is used to choose (among the other options) the reference standard, the safety factors, the

methods of computing the internal forces, the checks to run, and the check on the component

shifts. We check that Eurocode has been selected as the reference standard and that the

checking combinations are those from the imported FEM model. [click]




[chiudi]

For example, we can show the utilisation envelope [click] to find out the worst case

for each component.

The connection that we have built manually here is already in the archive. After

resetting the content of the current node, we can take a quick look at how to apply it

automatically, without going into details. [no post-process, azzera – applica il terzo

collegamento – eventualmente modifica dati piastra in background (600x240)]

If we want different dimensions, we can modify some of the parameters in real time

during the automatic construction, or we can make the necessary changes when construction

has been completed.


019 TOUR – CSE as a stand-alone program


[modello nuovo – versione FULL ( ? altrimenti rivedere)]

If a finite-element program with an interface to CSE is not available, the FEM models

for the connections to be analysed can be created in CSE itself.

There are three ways to create a FEM model directly in CSE. The first is to create it

freehand from scratch, by adding elements one by one, defining sections, materials,

constraints, end releases, offsets, etc. The second method is to choose one of the available

templates, defining the elements’ sections, material, end releases and – in some cases –

inclinations. The third option is a hybrid route, which involves starting from a predefined

template and modifying it manually. In the LIGHT version of CSE, the only method available

is the second one.

Once we have the FEM model, we move on to the automatic search for members and

jnodes. If we are using the predefined templates, these operations can be run automatically in

the background. In the LIGHT version, they are always run in the background.

To create a finite-element model, we first need to be in FEM view. Here we will need

to add the various beam or truss elements required and assign them sections and materials.

Suitable connection codes, end releases and constraints must also be specified. To define the

mesh, we can use predefined FEM models, such as splice joints, beam-column joints or

ground joints.

Once the FEM model has been created, first the members then the jnodes must be

found, using the dedicated automated commands. The renode must then be constructed by

positioning plates, angle brackets, generic-shaped extrudates, bolts and welds, as required.

[dialogo] Finally, once the settings for the checks have been specified, the renode can

be checked, taking account of the members’ elastic or plastic limits, suitably factorised, to

obtain the state of stress desired. In addition, check combinations can be imported from a

table.


To find out how to add finite elements manually, please see video 643 and sequels.

We will now look at adding the FEM model for a splice joint automatically. The Typical

nodes command (on the FEM menu) brings up a dialog box for the user to choose from

various standard connection types, which can then be modified according to requirements.

[scorrere tra i vari dialoghi] The diagrams show the finite elements, the connection codes

and the constraints for the various connections.

In this lesson, we are going to look at a horizontal splice joint [click]. After we click

on the selected structure, a dialog box appears for us to define the material and the sectional

forms.

A new material can be defined, or an existing one selected from the archive. Here,

we’ll choose S235. [click]

As for the material, we can define a new sectional form [click] or select one from the

archive. [click]

We filter for HEA sections and access the archive. [Click ] Only the sections of the

selected type are shown; the archive contains over 10,000 sections and can be extended using

the SAMBA software. We will choose the HEA300. [Click ] We assign the current section to

both members in the node. [click]

In this video, we will not discuss how to define hinges and rotate the sections. We can

tell the system to search for members and jnodes automatically in the background. Removing

the tick means we will need to start the automatic search ourselves. That way, we will be able

to see the various steps more clearly. This option is not available in the LIGHT version. [togli

spunta, OK]

In the FULL version, we are prompted whether to add a new node. We’ll say no. [no]

Let’s save the model. [salva]


The FEM model for the splice joint is now complete. One of the two members has a

connection code, to show that there is a discontinuity at that point, and that we are actually

dealing with two distinct members. We can see the elements’ section and material labels.

[mostra oggetti, etichette, sez. e mat.]

We run the automatic search for members. [click] Now we move on to the jnode view,

which shows the members that CSE has found. [click]

We run the automatic jnodes search: CSE will find all the different connections that

will then need to be worked on. If there are two or more the same, they will be associated

with the same jnode. In this case, of course, we will have a single instance of a single jnode.

[click]

If we select a jnode, we can move to the renode view, where the real three-

dimensional connection can be constructed and checked. [click]

The next videos show how to build real nodes; in particular, video 022 constructs the

node that we have obtained here.


020 TOUR – Beam-column joint (angle bracket)


[Tour_020.CSE, vista renodo, combi 27] [disclaimer per filmati brevi]

In this video, we will see how to build quickly a beam-column connection with angle

brackets, by adding the various components manually. Note that CSE has an archive of

standard nodes predefined in parametric form, which can be applied automatically. For more

on this functionality, see video 22 (among others).

In the FEM model, a suitable rigid offset has been defined for the beam, so that there

is no overlap with the master, and the member does not need to be trimmed.

[pannello pezzi selezionati, trave selezionata]

We add a double angle bracket. [click, solo lati uguali, L80x8; l=160, d=6.2, inserisci]

We insert the bolt layouts needed to connect the angle brackets to the beam and

column. [M14-8.8, 3x1, 50mm, solo taglio sull’anima ,taglio+trazione sulla flangia, inserire

i 3 layout]

The connection is constructed with all the components correctly connected. If

necessary, the column can be stiffened with welded ribs.

After checking the connection for consistency and for overlaps (not shown here), we

can run the check on the joint using the chosen settings. For how to define these settings,

please see the previous videos. Now we analyse the connection. [analizza]

When the checks are complete, the post-processing commands become available to analyse

the results.


For example, we can see the utilisation envelope [click], or we can show the deformed

view for the current combination [click]. The forces transmitted can be seen, along with the

results for the members’ net sections or for the bearing surfaces (not defined here).

[eventuale callout su nodi tipici, rimando a filmato 22]


021 TOUR – Beam-beam joint (welded)


[Tour_021.CSE, vista renodo, combi 25; creare ma non mostrare centri delle facce]

[disclaimer per filmati brevi]

In this video, we will see how to build quickly a welded beam-beam connection, by

adding the various components manually. Note that CSE has an archive of standard nodes

predefined in parametric form, which can be applied automatically. For more on this

functionality, see video 22 (among others).

A suitable rigid offset for the secondary beam has been defined in the FEM model in

order to provide the space to insert the plate that is to be welded. We insert the plate. [click,

360x160x15]

We weld the secondary beam’s web to the plate. [sp=10mm, su lati>250mm, dist.=10mm]

We add the bolt layout that joins the plate to the main beam’s web.[M16-8.8, 5x2, 70-

100mm; anche trazione]

The connection is constructed with all the components correctly connected. After

checking the connection for consistency and for overlaps (not shown here), we can run the

check on the joint using the chosen settings. For how to define these settings, please see the

previous videos. Now we analyse the connection. [analizza]


the results.


For example, we can look at the utilisation envelope [click]. Or we can show the

deformed view for the current combination [click, aumenta scala]. As we scroll through the

various combinations, the view is updated in real time. [combi 26, 27].

[eventuale callout su nodi tipici, rimando a filmato 22]


022 TOUR – Splice joint (flanged)


[Tour_022.CSE, vista renodo, combi 25]

[disclaimer per filmati brevi]

This video takes up where lesson 19 left off; we will see how to construct a flanged

splice joint automatically, by applying a predefined node. For manual connection

construction, please see the previous videos.

We apply a parametric node suitable for the current node, taken from the archive.

[click, scorrere fino ad AJ] For example, we can take this node. [click] The predefined

parameters can be edited; here, we are going to apply the node ‘as is’. [click]

The connection has been constructed automatically, with all the components correctly

connected. After checking the connection for consistency and for overlaps (not shown here),

we can run the check on the joint using the chosen settings. The process of setting up the

checks is not shown here; this is covered in the more detailed videos. [in pausa: limiti N+-,

V3 ed M2 = 0.2, il resto =0] We analyse the connection. [analizza]


the results.

For example, we can look at the utilisation envelope [click]. Or we can show the

deformed view for the current combination [click, aumenta scala]. As we scroll through the

various combinations, the view is updated in real time. [scorri, poi vai a combi 35]

[eventuale callout su costruzione manual, rimando a filmato 22]


030 TOUR – Non-typical joints


[callout: no criteri costruttivi l’obiettivo è mostrare la versatilità di CSE]

[carrellata modelli TOUR_CarrellataNonStandard_01-09.CSE, precedentemente aperti nella

stessa istanza]

In CSE, we can make generic joints that do not fall into the typical categories: this

means that connections can be modelled according to requirements without the need to

confine ourselves to the predefined templates. This is made possible courtesy of the facility to

arrange the entities freely in the scene and CSE’s ability to recognise the various connections

automatically based on the position of the entities.

In this video, we will see some examples of connections created with CSE.

[01] This very complex connection involves nine members, numerous force transferrers

made of angle brackets, rectangular plates, plates with ad hoc shapes and dozens of joiners

made of bolt and weld layouts. [rotazioni varie]

[02] This example involves two diagonal C-sections connected to a stanchion created with a

cold-formed section. [rotazioni varie]

[03] This ground connection was made from four diagonals converging to the same point,

bolted to a bevelled cross-form extrudate.

[04] Here we have a ground connection consisting of a cold-formed section with a pair of

angles bolted to it. [rotazione dietro] The base has a section that grips the stanchion and is

stiffened by a welded plate.


[05] In the splice joint shown, part of the two members’ webs has been removed. This

reduction in gross area can be considered in the analysis with an automatic check on the net

sections. [rotazioni varie]

[06] In this connection, a portion of the column’s flange has been removed, and its web is

connected to that of the inclined beam; bolted plates connect the webs of the two members.

[rotazioni varie]

[07] This connection is a splice joint between two members having a composite section, in

which the web of an HEA320 section is joined to the upper flange of an HEA220 section.

[rotazioni varie]

[08] The example shown now is a joint between two offset beams. [rotazioni varie]

[09] In this connection, 4 beams are connected to the column at different heights; the column

is reinforced with stiffeners at all these levels. [rotazioni varie]


100 WORKFLOW STAGES: the FULL version vs the LIGHT

version

Two different versions of CSE are available, called FULL and LIGHT.

The former is for advanced designers seeking to use the wealth of functionality offered by

CSE to the full.

The latter is for designers who want a fast and feature-rich tool for designing standard nodes.

[le due interfacce]

Given their different goals, the two versions of the software differ in terms of their command

sets, their interfaces, and the terminology they use.

While the FULL version takes it for granted that users have taken time to study some core

concepts, the LIGHT version expects a less in-depth familiarity – even though users of either

version will get more from CSE if they learn the key concepts that underpin it.

Broadly speaking, the LIGHT version is more straightforward to use, while the FULL

product is more powerful.

Because the two versions are different, their workflows can only be described separately.

Accordingly, different lessons are provided to discuss the workflow stages in each program.

Although the underlying software is the same, the LIGHT version masks and simplifies

some steps in the workflow; some of the features in the FULL product are not available in the

LIGHT version, and its purchase price is therefore considerably lower.

[finestra di avvio scelta modalità versione FULL]

The FULL version can also be used in LIGHT mode, which imitates the operation of the

LIGHT version.

[lista lezioni fasi di lavoro]

Lessons 100 to 149 describe the workflow stages for users of the FULL version.

[lista lezioni fasi di lavoro]

And lessons 150 to 199 describe the workflow stages in the LIGHT version.


Although the workflows in the two versions differ, they share the same logical (albeit not

necessarily operational) sequence, as described below.

[vista un modello FEM]

The starting point is a finite element model of the structure that we want to analyse. This

structure may be as simple as the minimum set of elements needed to form a single

connection.

Importing an existing FEM model, or creating a new one in CSE, is therefore the first step

that we need to take. The only finite elements native to CSE are beams and trusses. In

general, the former take six components of stress (axial force, shears, torque, and two

bending moments). The latter bear only an axial force that is constant along the element.

The FEM model can be displayed using a dedicated view (in other words, a particular way of

looking at the CSE model).

The second logical step (which CSE takes automatically, if requested) is to recognise the

members, which generally comprise several finite elements. A member is a straight-axis

prismatic element with no internal physical discontinuities (in its section or material).

The third logical step, which is also automatic and takes just a few seconds, is to recognise

the JNodes; these are the ideal points in space where two or more members are connected, or

where one or more members are affixed to something else. This “something else” may be

either the fixed reference system (“the ground”) or other existing parts that act as constraints,

modelled with elements other than beams and trusses (such as a column affixed to a floor

slab modelled with plate-shell elements).

The JNode concept is discussed in a dedicated lesson (number 200). Suffice it to say here

that, while it is certainly true that all JNodes are also nodes in the finite element model, not

all nodes in the finite element model are also JNodes.

The search for JNodes, which the program performs automatically, also finds all identical

repetitions of the same JNode, spatially rotated and/or translated into various positions. These

repetitions are known as instances of the JNode.


The members and JNodes in the structure can be displayed in a dedicated view: the JNode

view.

The fourth logical step consists of selecting the JNodes one by one and converting them into

Renodes. The concept of a Renode (or REal NODE) is discussed in a dedicated lesson

(number 200). So what is a Renode, essentially?

While a JNode is defined in a wireframe space (the members with their orientations are

reduced to their axes, and there is nothing else besides the members), the Renode is defined

in a 3D space in which the connection is actually constructed in full detail.

An individual JNode may, in general, be converted into infinite possible Renodes, using

different physical components, such as weld layouts, bolt layouts, plates or angle brackets.

Creating the Renode for a given JNode amounts to constructing the connections in three

dimensions, in all their physical and computational details. This stage can, in certain cases

(like those just mentioned), be fully automated.

Each individual Renode can and must be shown in a dedicated view, namely the Renode view.

This is available if and only if a single JNode only has been selected.

The generic Renode is constructed and verified using the Renode view.

The fifth logical step is to verify the Renode with the relevant stresses for each component

member, modifying the components (the number of bolts, the plate dimensions, etc.) as

required.

Once some or all of the Renodes comprising the structure (at least one of them) have been

built, the sixth and final logical step is to view the complete structure as a three-dimensional

construction, by adding all the components for all the various instances of all the Renodes

associated with all the JNodes. At that point, all (or some of) the connections in the structure

will have been fully defined and verified.

The overall 3D structure can be examined in a dedicated view: the Solid view.


101 FULL Stage 1a: importing the FEM model

Starting from an empty model, a ready-made FEM model can be imported using a single

command: File-Import FEM model.

The FEM model may already have been solved; if so, all the internal forces for all the

elements, in all checking combinations, will be available. In special cases, the model may be

imported without all the internal design forces being available. In the first case, the internal

design forces may be used to check the connections; in the second, these forces will be

defined using other approaches. These other approaches may be used even if the FEM model

is imported with its internal forces.

The FEM model may be imported if it is available in one of the formats supported by CSE.

Please see the user guide for which formats are available in the latest release.

If the FEM model has been imported with its internal forces, then every subsequent change to

the model will result in the internal design forces being lost, as they would no longer be

consistent with the model. There are exceptions to this general rule in certain special cases.

An imported FEM model is generally accepted ‘as is’. If the model has been modified after

the Renodes have been built, it can be updated without losing the work already done, as long

as this would not cause contradictions.

When constructing the FEM model, there are some rules that we need to follow; these specify

some additional information that CSE needs in order to understand exactly how the members

are made. This additional information consists essentially of the connection codes associated

with the extremities of some finite elements. See lesson 390 for a detailed explanation of this

issue.

The connection codes are only needed in some special cases. In others, all that is necessary is

a straightforward standard FEM model.


Once the FEM model has been imported into CSE, the members are also automatically

recognised, although the JNodes are not (yet). JNodes must be recognised using a dedicated

command (JNodes-Search) – see lesson 110.


102 FULL Stage 1b: manually creating or modifying the FEM

model

If there is no FEM model to import, or if (in exceptional cases) we want to modify a FEM

model that has already been imported, then the user can create the FEM model from scratch

in CSE or modify the FEM model imported.

CSE is therefore fully independent of any external FEM program.

To this end, CSE has a range of commands – in the FEM menu – for adding finite elements

and FEM nodes, assigning the cross-sections and materials to these elements, and assigning

constraints, end releases and connection codes.

These commands cannot and are not intended to substitute a complete finite element

program; accordingly, only a limited set of them is provided. Nevertheless, they are sufficient

for specifying the meshes (even, potentially, for a single connection between one or more

elements).

A FEM model created or modified in CSE has no internal forces in the elements deriving

from a computation. The user must select which internal forces to use, when setting up the

checks on individual Renodes.

By manually creating (small) FEM models, the user can define every potential connection –

including unusual ones – between different members, or between one or more members and

the reference (the ground).

Before searching for JNodes (see lesson 110), for the purposes of creating the FEM model,

the program first needs to be told to find the members, using the FEM-Search for Members

command.


103 FULL Stage 1c: automatically creating the FEM model

Because defining a FEM model manually requires a certain amount of practice and can

become a little tedious, CSE also offers the ability to create small FEM models automatically

and very easily for a number of typical, frequently used templates, such as for beam-beam,

beam-column and column-ground connections.

The command to use is FEM-Standard nodes. This command already knows which mesh

needs to be created as the user chose it; hence, it asks the user for the following information

only:

the cross-sections for the elements

their materials

the orientation (strong or weak axis)

and whether any hinges are present.

As already mentioned, the command already knows which mesh needs to be created, because

the user has already selected it.

The command automates various stages in the workflow, and automatically creates the mesh

needed.

In the FULL version, more basic templates can be added (each representing a different JNode

and, subsequently, Renode). A single model will therefore contain several nodes, thus

avoiding the need to have a separate file for each JNode. The mini-structures corresponding

to the templates are arranged separately, one after the other. Indeed, in terms of checking the

individual connections, what is important is only the local mesh, not the global one.

To make for efficient working, this command’s default behaviour is to search for the

members and JNodes automatically, immediately before the Renode creation stage.


This way of operating is especially useful if we need to define standard nodes (those whose

template is one of those provided with the FEM-Standard nodes command).


105 FULL Stage 2: searching for members

[img1]Members are phisically non-interupted elements, generally made up by a given

number of finite elements. The conversion of a FEM model (with nodes, beam and truss

elements) into a model made up by members is done automatically by CSE. Sometimes it’s

up to the user to start the automatic search, but usually the search is done in background and

does not need an input by the user.

Automatic search for members is done with the Search members command (in the FEM

menu). As already mentioned, users need to execute this command in some cases only,

because in others the search is automated in background.

In particular, if the FEM model has been imported, members search is totally automated and

executed during the importing. If the user does not modify the model after the importing, it is

not needed to execute the command for members search. The same holds true when updating

a previously imported model.

[img2]If the typical FEM structures tool was used to define desired nodes in CSE (Typical

nodes command) it is not needed to search the members, since they are found in background.

User can choose anyway to run the search manually, if he, or she, wants to.

[img3]If the FEM model was freely created in CSE, or it has been modified after the

importing or the automatic creation, the user has to run the Search members command of the

FEM menu.


110 FULL Stage 3: searching for JNodes

As we mentioned in an earlier lesson, searching for JNodes is essential in order to construct

the actual Renodes. The system searches for JNodes via a single command: JNodes-Search.

Sometimes, the JNode search is automatic, with no need for the user to invoke this command;

this is the case when standard templates have been created, using the command dedicated to

that end.

If a ready-made FEM model is imported, we will probably then want to run JNodes-Search

without making additional changes.

Searching for JNodes entails searching for all identical instances of that JNode. In CSE, a

JNode generally has several instances (or repetitions). By selecting a JNode, we select all its

instances, which typically may be scattered among various parts of the structure.

Every JNode is labelled with an alphanumeric descriptor, or "mark", such as “AA”, “AB”,

and so on.

Before starting to construct the Renode associated with each JNode, users are well advised to

check that the JNode search has produced essentially acceptable results.

A jnode can have a constraint or not. If there is not a constraint, there are members only,

connected together; if there is a constraint, members are connected also to it. The constraint

can be rigid (nodal constraint in the FEM model) or elastic (springs, solid, plate elements, etc.

in the FEM model).

JNodes are classified as follows (see lesson 201):

hierarchical (the most common type: a member with the other members attached to it)

central (several members connected together by a component – like a plate – all

interrupted)


simple (there is a single member, hence it is constrained)

cuspidal (two or more members without a connection code joined at the JNode)

pass-through (two or more members passing from one side of the JNode to the other,

without interruption).

CSE can verify only the first three of these types.

A JNode’s classification depends on how the members are logically and geometrically

connected. This also depends on any connection codes applied to the finite elements, and

consequently, to the members’ extremities.

Before proceeding further, then, if a FEM model has been imported, we may want to

amend it (using the software that we have) and then reimport it into CSE, in order to

eliminate pass-through or cuspidal JNodes, which generally result from a lack of information

in the FEM model. Given that importing the FEM model and searching for JNodes takes just

a few seconds, this is not a problem in practice.

If the structure has been created in CSE using the manual FEM commands, then we

may wish to go back to these commands, specify the connection codes more accurately, and

then repeat the search for members and JNodes.

If the structure has been created automatically in CSE using the FEM-Standard nodes

command, then it is already correct and no further adjustments are usually needed.

In the JNode menu, CSE offers a series of commands providing preliminary information

about the JNode, derived essentially from the underlying wireframe finite element model.

The JNodes are all described in a dedicated listing, which CSE can create automatically.

The preliminary information on each JNode, besides its mark and the number of instances,

also includes the envelope of the stresses on the members for all the JNode’s instances and

combinations, provided that (of course) a FEM model has been imported that had already

been computed and solved.


For large and complex models, it is highly advisable to perform a preliminary analysis of the

JNodes, in order to avoid finding defects in the FEM model after the Renodes have already

been constructed. If that does happen, though, it may be necessary to update the FEM model

using the relevant command (File-Update FEM model) so as not to lose Renodes that have

already been constructed.

If, however, no Renodes have yet been built, the model can simply be reimported and the

JNodes search repeated.


120 FULL Stage 4a: manually creating the Renode from scratch

Once we have selected a single JNode, by clicking on the little square representing it in any

of its instances, we can move into Renode view to build the Renode in a 3D working

environment.

The JNode is selected in JNode view. When a JNode is selected, all its instances are also

selected.

When in Renode view, we have a solid representation of the members that must be connected

together and/or to a reference. Initially, the members comprising the Renode run without

interruption up to the theoretical node in the FEM model, hence the elements will generally

have overlaps.

[step 1 modifica delle membrature]

Using a series of general commands – for modifying the members’ geometry,

[step 2 aggiunta di tramite]

correctly positioning new components in space (generally plates, angle brackets or profile

stumps),

[step 3 aggiunta di saldature e/o bullonature]

and adding joiners like bolt- and weld layouts –

[step 4: renodo finito]

the user constructs the Renode; the approach is a little like using a kind of virtual LEGOTM

.

[diversi modi di costruire un JNodo, dando luogo a renodi diversi]

Users can create Renodes with a free hand: the commands are very general and allow

members to be connected together in a huge range of different ways.

[aggiunta di un blocco vincolo]

If the JNode is an attachment (in other words, if the members are connected to something else

not in the model), then a constraint block will need to be added; this is an object that

schematically simulates the presence of the unmodelled part.

[diversi possibili blocchi vincolo]


A constraint block is a right parallelepiped simulating foundation plinths, grade beams, floor

slabs, walls or other structural features.

[renodo completo]

Once the Renode has been constructed, all the members and additional components (force

transferrers) will be connected. If this does not occur, because some components are free or

poorly connected, then the coherence check command can be used to pick up on this (see

lesson 306).

[dialogo impostazione verifiche]

At this point, the checks can be set up (see lesson 140) and run, and the results analysed

(lesson 145).

The Renode can also be created using commands that allow the user to modify geometrically

the previously added components

[zoom sui flag relativi ad una piastra, nel dialogo di modifica]

… and to alter their static behaviour and the checks to which they will be subject.


130 FULL Stage 4b: creating the Renode automatically or semi-

automatically

[dialogo con la lista dei PRenodi]

CSE offers powerful functionality for creating the Renode from scratch. Nevertheless, to

make it even quicker and easier to create standard Renodes, the program provides a library

of parametric Renodes (known as PRenodes).

[costruzione automatica di un Renodo scegliendo un PRenodo]

These can be called up for an empty Renode, to allow the entire Renode to be created

immediately

[finestra lista operazioni PRenodo]

and (more or less) interactively.

For a Renode to be constructed immediately via the application of a PRenode to the empty

Renode, the database of existing PRenodes must contain at least one that is applicable to the

Renode in question.

Of course, not all PRenodes can be applied to a generic empty Renode: they must have the

same number of members of the same type with the same alignments, and so on.

The software establishes which PRenodes are applicable to the empty Renode in question,

using a complex series of automatic checks. Of course, there may well be no compatible

parametric node for the Renode in question, in which case the list of applicable PRenodes

may be blank.

The Renode must then be constructed using the general manual commands.

Alternatively, users of the FULL version can add a new PRenode to the PRenode database,

by building the empty Renode in question parametrically; thus every time the same type of

Renode comes up in future, the PRenode just created will be available for use.


It is very important to realise that a PRenode may still be applicable to the Renode even if the

members have different dimensions. Indeed, the parameterisation already takes this into

account.

There may be a PRenode whose parameterisation does not quite meet the requirements for

the Renode in question. In such cases, the program enables the parameterised settings to be

altered “on the fly”, thus providing a simplified, guided means of building a different

Renode.

Creating a PRenode is akin to carrying out a series of basic operations that starts with the

initially empty Renode and turns it into the finished Renode.

Each of these basic operations is usually parametric.

When the PRenode is applied to the Renode, the program prompts the user for which

operations they want to run ‘as is’ and which they want to amend first.

In this way, the user can elect to have “n” operations run automatically and to modify another

“m” interactively, thus creating a final Renode that, although obtained from the PRenode, is

different from the version originally envisaged.

In addition, after constructing the Renode automatically, the user can then modify it using the

normal commands for creating and modifying Renodes, to achieve the solution desired. For

example, they can remove or shift some of the bolts or welds.

All this functionality provides the user with a powerful set of tools.


140 FULL Stage 5: setting up the checks

Setting up the checks is a crucial stage in using CSE properly.

Operationally, it involves two separate kinds of settings: those affecting how each component

is checked; and those concerning how the general checks are performed on each Renode.

Choosing how to check each component includes deciding which checks to run and which

not to;

for the FEM checks, it also entails selecting how the checks are to be carried out (whether to

use linear or non-linear computations, and which properties the mesh for the component

should have).

All these choices are made in the dialog box used to add or modify each individual

component.

For bolt and weld layouts, an important part of customising the checks involves looking at the

static behaviour of such layouts. For example, whether a bolt layout operates on a shear-only

basis, or otherwise whether a bearing support is needed,

or whether weld layouts use penetration welds or fillet welds.

To choose how the general checks are to be run, we need to use the Checks-Settings

command.

Here, we decide which groups of checks are to be run; this is effectively a second level on

which to make this decision: for example, we can opt to run the checks on the members’ net

sections, which at individual member level we may have decided to omit for that particular

given member.


The groups of general tests available are as follows:

[una immagine significativa per ogni verifica]

simplified force-transferrer checks (lesson 334)

block-tearing checks (lesson 336)

bearing-stress checks

punching checks

member net-section checks (lesson 333)

user checks (lesson 335; for the standard user checks, see lesson 380)

FEM checks for selected components (lesson 332)

displacement checks (lesson 370).

Checking the connections is a very complex business: there is no single approach that is valid

in all cases, and different methods may be required, depending on the type of problem at

hand.

Certain types of check will be useful in certain cases, and irrelevant or inadequate in others.

Checking a connection of a given type, for instance a bolted end plate, may involve different

choices depending on the surface used to simulate the bearing support, its constitutive law,

the number and type of checks to be run (only user checks, only FEM checks, both, or

neither) and many other factors, such as the relative thickness of the plate, the load on it, and

so on.

The purpose of the checks is not to establish what happens in physical reality, as no check

can do this. Rather, their purpose is to subject the Renode’s components to a core set of

standard checks that can detect certain possible types of failure in the built Renode.

It is no coincidence that some of the best publications currently available on computing

connections recommend a specific set of checks for each specific connection type. Different

checks are required depending on the circumstances. Given that CSE allows the user a free

hand when building Renodes, it is normally up to the user to decide which set of checks is

actually required in each case.


In general, each failure-mode check can be run in different ways. The formulae and methods

set out in the standards are conventional approaches with a certain scope of applicability.

It is the user’s responsibility to understand the checks that CSE runs and to select which of

them are most appropriate for their particular circumstances. In order to choose wisely from

the wide range of checks and options available, CSE users must therefore understand the

subject properly.

In terms of parameterising the standard nodes, the set of checks to be run can be pre-

packaged as a default, thus relieving the user of the need to decide. The PRenodes in the

archive are divided into two large groups distinguished by the images that identify the

Renode to be constructed.

The first group consists of the PRenodes to be verified with a pre-packaged set of checks;

they are identified by a green circle (like a green traffic light) in at least one of the images

that describe them (usually the first one). In this case, the checks may be run directly; the

person who built the PRenode also specified all the checks that were necessary and which

settings were to be used with them.

The other large group comprises the PRenodes whose checks have not yet been set up – not

completely or not at all. In this case, one of the images must contain a red circle. Once the

Renode has been built by applying the PRenode, the user will then have to select the

necessary options.

Both the FULL and the LIGHT versions of CSE come with a database of PRenodes, which

are mostly ready to use (that is, they belong to the first group). When adding new PRenodes

in the FULL version, users are advised to use the same convention to distinguish between

Renodes ready for use (group one, with a green circle) and those whose settings for the

component checks will need to be revisited (group two, red circle).


145 FULL Stage 6: running the checks and analysing the results

To run the checks, there is a single dedicated command: Checks-Check.

Once the command has been run, the user can view the results, analyse the implications, and

make any amendments to the Renode to make it work more effectively.

The result of the checks is a utilisation index, an absolute number that is less than 1 if the

check is successful, 1 or greater if not.

For each component, in every checking combination, only the greatest utilisation index is

stored, together with the check associated with it. In general, each component is subject to

several checks in the same load combination, and each of these gives rise to a different

utilisation.

The envelope utilisations are the maximum utilisations of a given component for different

checking combinations and different instances of the Renode. Checking a Renode, indeed,

involves not only all the load cases but also all the different instances of the same Renode in

the structure.

Besides the colour-coded map of the utilisation indices in a given combination and instance

of the Renode, there is also the output listing, which should be thought of as a tool for

obtaining all the detailed information needed to understand the outcome of the checks that the

program performs automatically. The colour-coded utilisation map and the listing are only

part of the information that the software provides about the results of the checks.

For each check that gives rise to a maximum utilisation index in a given combination and

instance, a range of additional information can also be displayed on screen. For example, for

the FEM checks, there is the map of the Von Mises stresses – this can be obtained by calling

Sargon Reader, an external application bundled free with CSE, using a dedicated command

from within CSE. For block tearing, the failure path can be seen. For the net sections, there is

the field of normal stresses on the generic net section, and so on.


The program output includes a deformed view of the Renode and the forces transmitted

between all the components.

All this data that CSE provides, when properly analysed, adds up to a rich harvest of

information for the designer to use, both in making design decisions (whether to accept the

Renode or modify it – and if so, how) and in documenting them in his or her calculation

report and the results achieved.

For instance, instead of showing the computations for a presumed “equivalent T-stub”, the

designer can attach the finite element analysis performed on the entity showing that the Von

Mises stress corresponding to the yield stress has not been exceeded, or for non-linear

computations, that the entity has not reached its load-bearing capacity or load limit.

In other cases, the designer may wish to clarify the compression distribution on the bearing

support and the tension in the bolts created by the axial force and bending moments applied

to a bolt layout.

And so on.


150 LIGHT Stage 1a: importing the model, searching for JNodes

The LIGHT version of CSE has been designed to be simpler to use, with a shorter learning

curve, thus reducing the need for users to know the complex data set that underlies it.

Accordingly, the LIGHT version spares the user from having to select JNodes or use the

corresponding view (although this is still available), by keeping the JNode concept in the

background.

It does so by supporting only a single JNode-Renode in each file. It is not therefore possible

to import complete FEM models, as these necessarily contain large numbers of JNodes.

If it becomes clear that typical users of the LIGHT version can learn to handle the JNodes

without too much effort, then this restriction could easily be removed.

For the moment, though, existing FEM models cannot be imported in the LIGHT version.


151 LIGHT Stage 1b: automatically creating the model for an

individual node

The LIGHT version works with one JNode-Renode at a time and aims to relieve the user of

the need to learn how to use the commands to add and modify individual finite elements, in

order to make the program simpler to use. The LIGHT version was conceived to allow

elementary templates to be added automatically for standard nodes (which we refer to for

simplicity as Nodes and not JNodes, as would be more correct, strictly speaking: see lesson

200).

The search for JNodes – which is logically necessary – is carried out automatically by the

software, without the need for any command to be run: the user is shown the Renode in its

initial form, with the overlapping members converging to the ideal theoretical node.

The command to run is Nodes-Standard nodes, available as the first button on the toolbar

with large buttons on the left of the user interface.

The system thus becomes very straightforward and immediate to use, albeit less general.

Users of the LIGHT version start by selecting a standard template for a standard node.

Then CSE automatically brings up the three-dimensional node (the Renode) in its initial

completely unsolved state.


160 LIGHT Stage 2: constructing the Renode

Unlike the FULL version, which gives users a free hand in creating the Renode, the LIGHT

version works with standard nodes, allowing the Renode to be created only by applying a

suitable PRenode – in other words, the user can build the Renode only by choosing a method

from a list of options.

The advantage of this is that the Renode is built automatically and immediately. The

disadvantage is the loss of generality – which is also why the LIGHT version costs less.

Of course, for a given template, only a few possible Renodes are available: normally the

more common, typical ones. In some cases, there may be no PRenodes at all.

In operational terms, the Renode is constructed automatically using the Nodes-Assign

parametric node command. This command is accessible from the second button on the

toolbar located on the left of the user interface.

The LIGHT version will become more powerful as the PRenode library grows. The number

of PRenodes currently available is as stated in the latest documentation (there were 170 in

CSE version 4.40, released in autumn 2011).

Constructing the Renode is a more flexible process than you might imagine. Indeed, each

parametric node (or PRenode) is treated as a list of parameterised elementary operations.

Each such operation can be run automatically, in accordance with the definition and the

parameters set up by the PRenode’s original creator; alternatively, it can be run interactively,

by modifying the original settings in real time.

For example, the number of bolts in a layout, where initially specified as a parameter, can be

entered directly: for instance, 3 rows by 2 columns; the same goes for the dimensions of the

plates and of each component. Where the parameter settings contain a formula, the formula

can always be changed, or numeric values inserted manually.


In this way, the PRenode can be customised to meet the current project’s specific

requirements. The only thing that cannot be changed is the node’s type and logic: for

example, if there is a weld layout, a connected end plate, or a double angle bracket, then these

must remain.

As well as modifying the individual operations during the process of assigning the PRenode

to the Renode, the user can also alter its individual components, via the usual commands that

are also available in the FULL version.

Users of the LIGHT version do not have access to all these commands, though, which

effectively means that they can essentially work only with the standard nodes in the PRenode

library (modifying them slightly, as required).

This node library is continually being extended and updated.

The facility to create new PRenodes in the FULL version opens up the possibility of

developing libraries of nodes for sale as separate packages to extend the LIGHT product’s

functional scope.


165 LIGHT Stage 3: modifying the Renode constructed

The Renode that has been built can be modified for various reasons: the checks may not have

been successful, or the initial arrangement of the various components in the PRenode may not

be suitable for the particular situation in hand.

The best way to modify a Renode in the LIGHT version is to reset it and build it again,

changing some of the individual operations that combine to make up the PRenode.

To reset a non-empty Renode, we use the Nodes-Reset node command, which can be

accessed from the third button on the toolbar on the left of the user interface.

By reassigning the PRenode to the empty Renode thus obtained, we can then modify one or

more of the individual operations comprising the PRenode. The dimensions of the entities or

the nature of the checks to be applied to them can thus be altered to suit.

If all we want to do is modify the checking options for an individual component, it is actually

much easier to select the component and use the Node-Components-Modify command.

On the other hand, if we need to adjust an entity’s size (for example, its thickness) or the

number of welds and bolts, then it may be convenient to edit the parametric operations that,

taken together, are used to automatically create the Renode.


170 LIGHT Stage 4: setting up the checks

If the Renode obtained is already ready to be checked, then we can go ahead and run them. If,

on the other hand, it needs to be customised to ensure that the checks run correctly, then the

user will need to:

1. select the checking options for each component, by “modifying” the component using

the relevant command (Nodes-Components-Modify).

2. run the Checks-Settings command and set up the general options as to which checks

are to be run, for all the Renode’s components.

As regards setting up the checks, the remarks made in lesson 140 apply here, with one

important difference.

Given that users of the LIGHT version work with pre-packaged nodes, it is very likely that

these nodes have already been set up by their original creator. If so, the Renodes as

automatically built are also ready for checking.

The PRenodes ready for checking are those with a green circle in one of the images that

describe the PRenode.


180 LIGHT Stage 5: running the checks and analysing the

results

The checks in the LIGHT version of CSE are run and the results analysed using exactly the

same procedure as for the FULL version. Please therefore see lesson 145, about the FULL

version, for details.


200 TERMINOLOGY: Nodes, JNodes and Renodes

In a finite element model, or FEM model, the elements are attached to very specific points in

space, called Nodes.

The Nodes generally have six degrees of freedom: three translations and three rotations.

On account of the mesh, the nodes in a finite element model do not always represent points

where different members are joined. Many Nodes in a finite element model do not

correspond to “Nodes” where members are actually connected.

The “Nodes” in the finite element model where several members connect together – and/or

with the reference – are known as JNodes (from Joint and Node).

In order to distinguish JNodes from Nodes, a model of finite elements must first be converted

into a model of members. A member is a physically unique entity with no internal

connections. It is generally modelled using several beam-type finite elements or one truss-

type finite element.

By examining the model of members, we can understand which Nodes are also JNodes.

If a certain number of members n are joined in a Node, just as precisely n others do in a

different node – with the same sections and the same mutual orientations – then the

connections must be defined once only, as they are the same. In CSE terminology, this is an

example of different instances (or repetitions) of a given JNode.

A JNode can therefore have many different instances.

In general, there will be a great deal fewer JNodes in a generic structure than there were

Nodes in the original FEM model.


A JNode contains preliminary information only, without detail, about how the various

connections are actually made.

A JNode is defined in a wireframe, i.e. in a 1D-, not a 3D-, space.

For a single JNode, there may be many different ways of physically implementing the

connections, which may be welded or bolted, or involve plates of various shapes, or other

components.

In effect, there may be any number of different ways of physically building the actual

connections for a given JNode.

The set of all the entities and joiners uniquely defining how the connections in the JNode are

physically implemented, and the set of all the computational rules specifying how they are

calculated, comprise what in CSE is referred to as a Renode (from Real Node).

CSE has dedicated views for Nodes, JNodes and Renodes, namely FEM view, JNode view

and Renode view. The first two are wireframe; the third is solid.


201 TERMINOLOGY: Classification of JNodes

The JNodes must be classified for the purposes of the subsequent automatic computation

stage. They fall into a number of broad types.

A JNode is said to be hierarchical if it is the point where several members converge, of

which one – and one only – is attached to all the others. This member is known as the master

member and is always numbered 1 in the JNode’s list of members. The others are called

slaves. The master is the member (in the Node corresponding to the JNode) with no

connection codes or end releases.

A JNode is said to be central if all the members joined at the JNode are connected to a

central entity that unites them. This entity is not a member but a force transferrer. All

members joined at the JNode must have a connection code or an end release there.

A JNode is simple if it comprises a single member constrained to a reference.

A JNode is cuspidal if two or more members that are joined at the JNode (which is one of

their extremities) have no connection code or end releases there.

A pass-through JNode is one that has two or more pass-through members. A member of a

JNode is a pass-through member if none of its extremities coincide with the JNode itself.


202 TERMINOLOGY: Joined members, joiners, force

transferrers, and stiffeners

The components of a Renode fall into four broad groups:

1. Joined members, i.e. the member or members that meet in the Renode;

2. Joiners, i.e. means of connecting entities, like bolt layouts or welds;

3. Force transferrers or also "throughs", i.e. those additional components – like plates

or angle brackets – that are neither joined members nor joiners and that are used to

transfer forces from one component to another;

4. Stiffeners, which are a special type of force transferrer (see lesson 203).


203 TERMINOLOGY: Stiffeners vs force transferrers

In CSE, a force transferrer is a component X that transmits a certain set of forces from

component A to component B. By definition, no member can be a force transferrer – nor,

therefore, can a bolt layout or weld layout. Typical force transferrers are plates, profile

stumps, and single or double angle brackets.

In CSE, a stiffener is a component that transmits forces from one part of a component to

another part of the same component.

Although some force transferrers, in the generally understood sense of the term, are used as

stiffeners (such as the plates joining a column to its base plate), these will be treated within

CSE simply as force transferrers and not stiffeners per se.

The distinction is important, because stiffeners (in the CSE sense of the term) are not subject

to any checks, unless:

the component that they stiffen undergoes the FEM check (to find the stiffeners);

specific user checks on the stiffeners have been added.


204 TERMINOLOGY: Rigid or elastic attachments

The internal forces at the members’ ideal extremity may be in overall equilibrium or may

require additional forces, exerted by constraints.

In the latter case, the JNode is an attachment.

If the constraint is simply a nodal constraint in the FEM model, then the attachment is rigid.

Otherwise, if there are also (or only) finite elements like plates, membranes, solids or springs

that are not present in the CSE model, then the attachment is elastic.


205 TERMINOLOGY: Bearing support

A bolt layout subject to bending can resist the moment applied via the tension in its bolts and

the compression in a surface that acts as a unilateral contact. The component to which this

surface belongs is referred to as a bearing support.

The surface in question is called a bearing surface.

The definition of the bearing surface and that of the bearing support’s constitutive law have a

determining influence on the bolt layout’s static behaviour.

The bearing surface must take account of the bearing support’s actual ability to exert the

compression forces required: overly weak areas must not be used as bearing supports. See

lesson 801 for a more thorough discussion of this problem.

It is up to the user to decide on a bearing surface and a constitutive law for the bearing

support that are suitable for the problem in hand, taking into account the nature of the

components connected, be they simple plates (of varying thickness and stiffness), surfaces

made of concrete, outlines of sections with suitable projecting borders, or something else.


207 TERMINOLOGY: Predefined variable

Each component in a Renode is created with a well defined set of variables associated with

it. These are called predefined variables.

Predefined variables are very useful where the user wishes to add special checks of their own,

known as user checks.

User checks are typically inequalities using predefined variables and other variables added by

the user (called user variables).

Besides the variables associated with a given entity (let’s call it “A”), all in the form

“A.(‘dot’)”, CSE also automatically adds some global variables, which can be recognised by

their prefix “gl.”, where the “gl” stands for “global”.

Predefined variables may have different physical dimensions: they may be lengths, areas,

volumes, absolute numbers, forces, couples, or units derived from them.

Among the predefined variables, the internal forces at the members’ extremities have a

special role. For example, the axial force on member 3 is given by the variable “m3.N”.


208 TERMINOLOGY: User variable

As the name implies, user variables are variables added by the user to simplify the process

of setting up user checks or to manage quantities considered useful for design purposes.

The variables are named by the user. If a user variable is associated with a particular

component, it is advisable to choose a name that begins with the component’s name, followed

by a dot. For example: P1.whatever, P1.Nlim.

It is also possible to define variables which assume different values depending on different

conditions. These variables are called “if variables”. For each condition or value, numbers or

formulae can be defined.

If the first condition is true, the variable is equal to the first defined value. Otherwise, if the

first condition is not true and the second is true, variable is equal to the second defined value.

And so on.


209 TERMINOLOGY: User checks

Designers may not always find the automatic checks programmed into CSE sufficient.

Sometimes it can be necessary to have the software perform special new checks, for specific

design purposes.

As such, user checks are inequalities defined by the user to represent the additional checks

that he or she wishes to carry out.

In general, the user checks depend on the internal forces in the members – either directly,

when the inequalities directly use variables like .N or .M2, for example, or indirectly, when

the checking inequalities include variables that depend in their turn on the internal forces at

the members’ extremities.

In running the checks, for every combination and instance, CSE updates the values of the

internal forces in the members, before evaluating all the variables and all the additional

checking conditions.

If a user check has been defined in the form A<B, then an index of utilisation can be

defined, such as A/B. This is an absolute number. Indeed, the dimensional analysis requires

that A and B be defined so as to have the same physical dimensions.

The user checks are a very general and powerful tool for designers, who can thus use CSE to

perform precisely the structural checks that they want.

Although the vast majority of checks are carried out by CSE automatically without the need

for user checks, in some cases it can be useful to add some user checks, either to complement

the system’s basic checks or to run them in a different way, to obtain different, independent

results.


Not all user checks involve the internal forces in the members, whether directly or indirectly.

Sometimes, the user checks verify that suitable dimensional proportions have been achieved

or that certain preliminary conditions have been met.

A special case arises, in the form of the “standard checks” – these repeat certain checks from

the reference standard (for particular, specific problems), using formulae that are completely

indistinguishable from user checks.

The only difference is that the latter are added manually by the user, while for the former, the

system just prompts for some basic information and then adds the necessary inequalities itself

automatically.


301 TOPICS: Modelling the objects in CSE

CSE is a very general program, effectively because the model that it uses to describe the

three-dimensional objects is itself very general.

In CSE, a three-dimensional object is a collection of plane faces, whose normal versor

projects outwards from the object. Together, the faces describe the external surface of the

solid.

This representation, known as B-REP (Boundary Representation) provides a very general

way of defining a huge range of possible three-dimensional objects.

In CSE, many curved surfaces for the most common objects can be represented via a series of

plane faces simulating the curved contours of the surfaces of the real objects.

The three-dimensional representations of objects in CSE are very faithful to the real objects;

they can correctly detect problems like overlaps between different objects, or reflect the

presence of bevels, notches and a very general range of work processes.

For bolt layouts, CSE uses a conventional representation. Although some categorisations

define bolts by a head, a shaft, one or more washers, and a nut, while others use various

different complex entities of their own, CSE represents bolts (in Renode view and in Solid

view) as two hexagonal-based prisms – one for the bolt head, the other for the nut. These

prisms have the actual dimensions of the corresponding parts of the real bolt.

This simplification facilitates a faster and more schematic graphical display, without

sacrificing the key information, namely:

the net length of the bolt, i.e. the overall thickness of the bolted objects;

the planes corresponding to the contact surfaces of the internal faces of the bolt

head and the nut.


For fillet weld layouts, the various seams have a standard representation, as per the

computation models. Each weld is treated as a triangular-based prism.

For penetration weld layouts, CSE uses a conventional representation. The fused material

within the thickness of the welded entity is not represented. The weld is represented by a

triangular-based prism, of a different size to that used for the fillet welds, simulating a

“smear” of material outside the welded area as such. In any case, the information on the

penetration of the weld is retained correctly.

Hollow objects (such as tubes) are represented using a dummy cut that enables the solid to be

treated as mono-connected. This cut is used only to facilitate displaying the objects

graphically.


302 TOPICS: Representing joiners in CSE

In CSE’s graphical user interface, bolts are represented like this:

if they are shear only, they have no distinctive marking;

if they are tension-shear, they have a dot in the middle;

if they have a preload, they are shown with a triangle on the head;

if, besides the preload, the bolt layout is also slip-resistant, then the lateral faces of the

bolt heads also have a diagonal line;

finally, for anchors, the end of the anchor is shown emerging from the end of the

constraint block, for ease of identification.

When the results of the checks are displayed (including the envelope and the deformed

views), these bolt functions are not shown.


303 TOPICS: Identifying objects in CSE

Each of the objects making up a Renode needs to be uniquely identified. CSE does this by

giving each component a unique short alphanumeric identifier. This identifier acts as the

prefix for the predefined variables associated with the component. For instance, P1.b stands

for the width of plate P1.

The identifier for the members consists of the letter “m” followed by a progressive number

starting from 1. In hierarchical JNodes, the master is always m1.

The identifier for bolt layouts consists of the letter “B” followed by a progressive number.

For weld layouts, it comprises the letter “W” followed by a progressive number.

The constraint block – of which there is usually at most one – is identified by the string “|---

|”.

Plates are identified by a code consisting of the letter “P” followed by a progressive number.

For profile stumps, the code is “T” followed by a progressive number.

And so on.

CSE suggests a unique identifier for every new component added, although the user can

change it if they wish.

Every identifier is unique and can be used for one component only.

The finite elements in the underlying FEM model are identified by a progressive number.


The members are identified by a progressive number.

JNodes are identified by an alphanumeric code, such as “AA”, “AB”, etc.


304 TOPICS: Connection

The connection is a key concept in CSE and needs to be clearly understood.

For two components to be connected, they must have plane faces in contact such that the

normals emerge in opposite directions (otherwise, the two objects would overlap). The two

touching faces, which lie in the same plane, must also have a common surface. In particular,

the face of an individual weld seam or bolt, or of any single joiner, must be contained entirely

within the face of the linked component.

CSE automatically recognises the connection based on the objects’ spatial positions, without

the user needing to tell it which objects are connected.

Let’s now look at connections for bolt layouts in more detail.

Each bolt is represented by two hexagonal-based prisms. One simulates the bolt head; the

other, the nut. If the internal face of the prism representing the bolt head lies entirely on one

face of element A, then the bolt is connected to element A. A bolt layout is connected to

element A if the internal faces of all the prisms representing the bolt heads are in contact with

and coplanar to one of A’s faces.

A bolt-layout connection is re-constructed by examining the connection for each of its bolts.

All the bolts in a layout must connect the same objects in the same sequence.

Each bolt has an axis, defined as the line joining the centres of the hexagons representing the

outer faces of the two prisms that simulate the bolt head and the nut. The axis direction is

from the bolt head to the nut. The bolt axis is normal to the hexagonal faces.

The sequence of thicknesses of the objects joined to the bolt determines its connections. A

bolt may connect up to ten different thicknesses, which in general will belong to different

entities.


The objects are numbered progressively, from the one touching the bolt head, up to the one

touching the nut. The last of the connected objects is touching the nut’s internal hexagonal

face, which is coplanar with the face of the last of the connected thicknesses.

If the bolt is shifted so that the faces are no longer tangential to those of the connected

objects, then the connection ceases to be recognisable. Each bolt has two faces in contact

with other objects: 1) the internal face of the bolt head, which is touching the first of the

connected objects, and 2) the internal face of the nut, which is touching the last of the

connected objects.

The bolt shaft is not modelled in CSE.

A bolt layout may connect from 2 up to 10 thicknesses, belonging to objects that may, in

general, be different.

We will now take a detailed look at connections for weld layouts.

A weld layout comprises a certain number of welds, each connecting two different objects.

All the welds must connect the same two objects.

For fillet welds, two of the three lateral faces of the prism that defines each seam are called

active faces. Each of these faces is connected to a different object.

All the active weld faces that connect object A must lie in the same plane, “P”, which is also

the plane containing one of object A’s faces.

All the active weld faces that connect object B must lie on faces belonging to B; and each of

these faces of B’s must have an edge that lies on plane P, as defined a moment ago. All these

edges belong to faces lying on plane P.

If the weld layout is shifted so that contact is broken, then the connection can no longer

be recognised.


In CSE, any joiner may have sub-components (individual bolts or welds). All the sub-

components must connect the same objects. A bolt layout or weld layout cannot be defined

where some sub-components connect objects A and B, while others connect objects A and C.

If this occurs, the program will report an error during the coherence check.


305 TOPICS: Chains

The internal forces ideally present at a member’s theoretical extremity must be transmitted

from the member’s connections to another component, which may be a reference member

(in hierarchical JNodes), an entity connecting several members (in central JNodes) or a

constraint block (in attachments).

In each case, the internal forces ideally applied at a point are distributed between various sub-

components and joiners (weld and bolt layouts) along a physical or logical path, which may

be described using the concept of a chain.

A chain is a sequence of components that begins with a member “A” and finishes with

another component “B”. There may be several chains between A and B.

Given that two components may be joined only using joiners, chains are formed by a

succession of sequences of the following type:

*J*

C

where “*” means “joined to”, “J” stands for a generic joiner, and “C” stands for “generic

component”.

The program will, of course, use the name of the specific component and joiner instead of C

and J.

For example, consider a column (member m1) welded to a plate P1 via weld layout W1; the

plate is also connected to constraint block |---| via bolt layout B1.

The (unique) corresponding chain will be:

m1*W1*P1*B1*|---|

CSE automatically reconstructs the chains in a Renode; this helps us understand if the

Renode is properly coherent. Thus we can also understand if a given connection has been

correctly interpreted by the program.


Analysing the chains enables the system to detect if any entities are badly connected or

unconnected, and it is therefore useful as part of the preliminary analysis of the Renode.


306 TOPICS: Renode coherence

In order that the system can compute it, each Renode must be coherent.

This means that there must be no computationally meaningless situations, such as:

unconnected entities,

joiners connected to one component only,

joiners with two sub-components (individual bolts or welds) connecting different entities in

the same layout.

The Renode coherence check is performed using the Renode-Check coherence command.

This should always be run before moving on to verify a Renode, in order to be sure that

everything has been modelled correctly.


307 TOPICS: Overlaps

CSE can detect when two entities overlap. This is physically impossible and must be avoided.

Although conventional, the 3D representation of the objects in CSE is faithful enough to

enable the various dimensions – and, indeed, any overlaps – to be analysed accurately.

This helps avoid designing impossible connections.


308 TOPICS: Work processes

By work processes, we mean those modifications to the form of an entity that are made in

order to adapt it to the design aims.

These work processes may comprise:

Applying bevels (circular, square or triangular) to the edges of a component;

Rotating a face of a component;

Translating a face of a component;

Removing a rectangular-based prism;

Removing a polygonal prism.

The work processes enable entities of a given original form to be adapted to suit particular

design requirements.

Bevels and prism removals, in particular, allow us to simulate cutting part of an object and

thus to obtain complex non-prismatic forms.

Work processes are assigned to an object and then applied sequentially.


310 TOPICS: Bolt layouts

A bolt layout is a type of joiner that can function in different ways. CSE supports layouts of

bolts that all belong to the same plane. Bolts can be arranged on the plane however the

designer wants.

The plane where the bolts are to enter the material of the first entity to be joined is selected

by the user, by clicking on a face belonging to an object in the scene.

A fundamental initial distinction can be drawn between shear-only bolt layouts and

moment-resisting bolt layouts.

Shear-only bolt layouts of a given stiffness can absorb shear forces and torque only, which

all create shear in the bolt shafts.

Shear-only bolt layouts have very limited bending stiffness. Hence any bending moments

applied migrate to other, stiffer components.

If there aren’t any, then the bending is taken by the shear-only bolt layout anyway, albeit at

the expense of extremely high (dummy) displacements. Such a connection is badly

designed: either the bolt layout cannot be shear only or other bolt layouts are required (shear-

only or otherwise) to absorb the bending moments applied.

If a bolt layout is not shear only, it can withstand bending moments. There is a very

important distinction here between bolt layouts that use a bearing support to absorb the

bending and those that do not.

Layouts without a bearing support absorb the applied moment via tension and compression

forces in the bolt shafts. This approach, although good for safety, can often be too extreme.

If, on the other hand, the bolt layout does use a bearing support, then the bending is absorbed

by the tension in some of the bolts and by the compression in the bearing support.

The bearing surface’s size and constitutive law determine the static behaviour of bolt layouts

with bearing supports. Lesson 801 goes into this in more detail.


A bolt layout can be slip-resistant, in which case the coefficient of friction and the preload

for the bolts need to be specified.

A bolt layout can be an anchor. Here, an equivalent anchor length and a tangential bond

stress must be specified.

The bolt checks are always run completely automatically in CSE.


320 TOPICS: Weld layouts

In CSE, welds can be full- or partial penetration welds or fillet welds.

Each weld has a throat section or a thickness. Users can set the weld lengths to suit their

requirements and position the welds where they wish along the edges of the selected face (the

face of object B that is touching object A).

Welds are checked in different ways depending on whether they are fillet welds or

penetration welds.

CSE always performs the weld checks completely automatically.


330 TOPICS: Internal forces needed for checking

The process of checking Renode’s components always begins with the internal forces at the

ideal extremities of the connected members.

The program can obtain these internal forces in various ways:

1. via an existing and already computed FEM model, with the combinations defined

therein, from which the CSE model is derived (FEM combinations);

2. by allocating proper fractions of the elastic limits of the members’ transverse sections,

as decided by the user, and the dummy combinations generated by the program

(dummy combinations);

3. by allocating proper fractions of the plastic limits of the members’ transverse sections,

as decided by the user, and the dummy combinations generated by the program

(dummy combinations);

4. by directly allocating the limit values of the members’ elementary actions, as decided

by the user, and the dummy combinations generated by the program (dummy

combinations);

5. from tables of values determined by the user, for a number of combinations

determined by the user (user combinations).

Method 1 can be used only if a solved FEM model is available.

Methods 2, 3 and 4 differ only in that the reference values are given:

in one case as fractions of the elastic limits (2),

in another case as fractions of the plastic limits (3),


and in the other case as explicit numeric values (4).

In all three of these cases, for each member, the user specifies the computation values (the

maximum values possible) for the six elementary actions (seven if we bear in mind that

the axial force is split into tension and compression). The program then combines these

values together into 24 dummy combinations for each member in the Renode.

Method 5 provides the greatest flexibility for the user, who can determine both the number

of combinations and the precise values for the simultaneous internal forces. In practical

terms, the user can simply paste from an Excel table.

The method to use is chosen when the settings are specified for the checks on the Renode in

hand, using the Checks-Settings command.


331 TOPICS: Dummy combinations, user combinations and FEM

combinations

CSE runs the checks in all the required combinations. For each combination, the internal

forces at the members’ extremities need to take certain values.

If an already solved FEM model has been imported, then the combinations – referred to as

FEM combinations – are precisely those that were defined in the FEM model. The

combinations effectively take account of the planned internal design forces.

If, however, the combinations are the dummy ones generated by the program, then these

combinations – known as dummy combinations – are generated automatically by CSE based

on the stresses at the members’ extremities as defined by the user. There are 24 such

combinations per member. Each member’s 24 combinations are as follows:

six combinations where only the elementary actions whose sign is positive are

present, without any other actions (axial force only, shear only, etc.); the intensities

of these elementary actions are set by the user;

a further six combinations use only the elementary values of the actions whose sign is

negative;

the other 12 combinations are all obtained by combining the axial force N and the

corresponding member’s two bending moments, according to engineering, reasonable

fractions of the one-force-only limits.

Where the combinations are generated automatically by the program (dummy

combinations), what actually happens in physical terms is this. Each member is tested

separately in terms of each elementary stress, so as to take into account all possible ways of

detaching it from the connection (6 + 6 combinations). Then it is tested for simultaneous

axial force and bending moments (12 combinations, making a total of 24 combinations for

each member). As mentioned earlier, the reference values may be suitable factorisations of

the elastic or plastic limits (for example, to take account of the overstrength values) or

explicitly defined values.

The combinations defined by the user, known as user combinations, which can be set up by

importing an Excel table, use 6n values for each combination, where n is the number of


members in the Renode. For each combination and each member, 6 elementary actions must

be specified, considered as acting simultaneously.


333 TOPICS: Member net-sections checks

The members are de Saint-Venant prisms; hence, they can often be usefully checked without

the need of the FEM checks.

The prism is intersected by planes normal to its axis at all points where its original transverse

section has been modified, for example by bevels or notches of all kinds, or by bolt holes.

Each of the “net” sections is computed using a complex algorithm that considers the section

as composed of a vector of closed polygons, simulating the “solids” and “voids”.

In each net section, all the internal forces are computed: axial force, shears, bending moments

and torque. These forces are due to the individual contributions of the individual bolts

and the individual parts of individual welds; all these elementary contributions are

“outside” the net section, towards the member’s theoretical extremity.

The net section is then verified using typical checking formulae for beam sections.

The net sections check tends to eliminate the need for FEM checks, although every case

should be carefully treated on its merits.


334 TOPICS: Simplified force-transferrers checks

revisione: marzo 2012 – SERVE ULTERIORE INTEGRAZIONE

The problem of checking entities with complex shapes can sometimes be addressed using

simplified checking rules.

Simplified resistance checks for force transferrers can be divided in two groups: net

sections check and standard sections check.

Net section checks for throughs (force transferrers) is similar to net section check for

members (see previous lesson): the difference is in net sections individuation. For the

members, these sections are found only where there is a reduction of the gross cross-sections

due to holes, bevels, cuts, etc. Sections are normal to member axis. For the throughs, net

sections individuation is more complex and depends from the type of the component. Net

sections are not found only if there are holes or other reductions, but also in correspondance

of critical geometrical points, welds, etc. See the guide for more information.

Note well: now it is also possible to define user’s sections in a free way.

Each relevant section found by CSE is checked considering the effective forces acting on it.

For some kinds of throughs, there is also a standard sections check in addition to net

sections check.

This check take suitable, usually rectangular, predefined sections of the component in

question and consider the stresses acting on them.

The check is then run with formulae valid for checking beam elements, summing the

contributions due to the axial force, bending moment and shears.

The simplified checks complement the bearing-stress, punching and block-tear checks, and

can obviate the need for more sophisticated checks.


335 TOPICS: User checks

Sometimes, checks are needed that are not part of the program’s existing repertoire.

CSE provides users with a very powerful set of tools for defining the checks that they need,

using checking formulae based on predefined and user-defined variables.

These checks are known as user checks, and they are always associated with a particular

component in the Renode.

User checks make it possible to program CSE to meet virtually any requirements.

User checks are very easy to set up.


336 TOPICS: Block-tear checks

Block-tear checks look at the possibility of part of a sheet becoming detached under the

action of a set of forces coming from the bolt shafts.

These checks are only partly formalised by the current standards.

CSE takes a very general approach to the problem, by considering each bolt layout and

examining the sheets that it connects.

In general, each sheet is polygonal in shape, with a certain thickness, and is subject to

concentrated forces originating from the bolt shafts. The forces generally vary in intensity

and direction from bolt to bolt, in every combination for every instance of every Renode.

The program considers a large number of possible failure paths, under both shear and

tension (as well as shear and tension combined), and calculates an estimated ultimate load

for each path. This ultimate load is then compared to the force resulting from the sum of the

elementary forces for the subset of bolts involved in the failure. This then gives a coefficient

of utilisation. The program stores the utilisation due to block tearing, calculated as the

maximum utilisation for all failure paths examined, in the instance/combination examined.

The utilisation is associated with the entity to which the sheet in question belongs.

Although included in the standards, the block-tear problem is still the subject of ongoing

study and research. The algorithm used by CSE is very general and aims to resolve even

cases not covered by the standards (such as when the shear is offset from the bolt layout

center).


350 TOPICS: Bolt-layout checks

CSE always performs the bolt-layout checks automatically. Starting from the stresses

acting on the bolt layout as a whole, the checks determine the shear and tension in each

bolt shaft. These elementary forces (N and V) are then used to perform the strength checks

required under the standards.

The shear depends on the shear forces applied to the bolt layout and on the torque. The

shear force in the bolt shafts depends on both components of the stress. The shear due to the

torque increases linearly with the distance from the centre of gravity, and its direction is

perpendicular to the line joining the bolt and the centre of gravity of the bolt layout, as per all

the existing standards on connections.

The tensile (or, in some cases, also compressive) force in the shafts depends on the axial

force and the bending moment applied to the bolt layout, as well as on its mode of

operation – in particular, whether there is a bearing support.

Given the shear acting on a shaft, the slipping check in the slip-resistant joints can be run

automatically. The bearing-stress check can also be run.

Given the tension in a bolt shaft, the pull-out check can be performed when the layout is an

anchor. The punching check can also be run.


360 TOPICS: Weld-layout checks

CSE always performs the weld-layout checks automatically.

Starting from the stresses acting on the weld layout as a whole, the checks determine the

force per unit length absorbed along each weld.

This force per unit length is then used to perform the strength checks required under the

standards.


370 TOPICS: Displacement checks

CSE calculates the displacements of the Renode’s components. The displacements thus

computed can be used to assess whether a connection is well set up or well designed.

The displacements are calculated in a conventional manner, based on the approach taken

for computing the Renode, which in turn, takes account of the stiffnesses of all the joiners in

the Renode, as well as the way they operate (for instance, if a bolt layout is shear only).

Aggiungere spiegazione del significato degli spostamenti (spostamenti elevati=collegamento

mal progettato); non è importante il numero esatto quanto l’ordine di grandezza


380 TOPICS: Standard checks

Some checks required under the standards are not run automatically in CSE, since they relate

to very specific design scenarios that the program cannot recognise by itself.

These checks can very easily be added as a kind of user check, simply by telling the system

about the situation involved and how the minimum input data must be computed.

The program will automatically add all the formulae needed. From then on, the checks

added will be indistinguishable from regular user checks.

In general, for every standard check required, the program confines itself to asking about the

minimum input data (for example, which component is involved or what the design force is).

Given that CSE supports not only simple scenarios but also highly complex ones, the user

must “explain” to the program what data to use.


390 TOPICS: Connection codes in the FEM model

The existence of connection codes in the FEM model helps CSE to understand where the

members terminate and which members must be considered non-interrupted.

Connection codes are applied to beam elements only.

The following rules apply.

A truss element has no need for connection codes, for it always constitutes a member with

connections at its extremities.

If the extremity of a beam element has end releases, then these always involve a connection

code as well, which is effectively added automatically.

If there is a connection code but there are no end releases, then the beam element is clamped

at the node, although from a constructional perspective, it will be interrupted by the

node itself. It cannot therefore be part of a master member in a hierarchical node.

Furthermore, if as well as the node, there is another element with the same section and

alignment, then the latter element cannot belong to the same member.

If there is NO connection code and NO end release, then the element is NOT interrupted at

the node, neither statically nor in constructional terms.

Consider four identical elements in a cross-formation, all converging to a node. They are

aligned in pairs, with identical orientations. Depending on how the connection codes are set

or not set, there may be two to four different members. The node may give rise to a

hierarchical, central, cuspidal or pass-through JNode.

In particular:

No connection code: two pass-through members, pass-through JNode


Four connection codes: four members. Central JNode

One connection code: three members, of which one is a pass-through member. Cuspidal

JNode

Two connection codes: three members, of which one is a pass-through member. Hierarchical

JNode

Two connection codes: four members. Cuspidal JNode

Three connection codes: four members. Hierarchical JNode


400 INTERFACE: Overview

NON ANCORA RIVISTO

[versione FULL; immagine fissa]

[callout: 1. “FULL VERSION”]

The interface of CSE FULL version is shown in the first part of the movie. The

LIGHT version is similar but has some differences; it is shown in the second part.

The interface has two different views: the graphical one and the alphanumeric one.

The following information is shown in the graphical view:

FEM, jnodes, renode and solid views of the model, possibly with utilisation ratios

the results referring to bearing surfaces on bolt layouts using a compressed surface to

carry loads

the results referring to members net sections, that is the normal stress distribution over net

cross-sections

The alphanumeric view is divided into three panels containing information about:

the real node components

the selected real node components

the variables and conditions

See the movie 401 for a detailed description of the views.

In the upper part of the main window there are some menus with all the available

commands. Movies from 500 on show the menus.


Most frequent commands can be quickly executed using the buttons of the toolbars.

These toolbars are shown in movie 402.

In the lower part of the window there are two status bars, printing details referring to

active commands and other information.

The current combination, instance and units are given at the right extreme of the status

bar.

[salvare audio, poi passare alla versione light]

[callout: 1. “LIGHT VERSION”]

The interface of the LIGHT version is basically the same of the FULL one, with these

differences:

menus and toolbars have a reduced number of commands, since some

commands are not available in the LIGHT version;

the toolbar on the left is simplified and with bigger buttons;

the solid view is not available.


401 INTERFACE: Views

revisione PR gennaio 2012

[modello: Interfaccia.CSE, vista fem dopo essere passati in renodo e aver cliccato sul pannello

renodo]

CSE has a graphical view and an alphanumeric view. Only one of them can be

currently active. Just click into a view to activate it. [callouts, riquadri, ecc.]

Four different views can be displayed in the graphical view (only three of them are

available with the LIGHT version of the program). When the graphical view is active, it is

possible to switch from a view to another one.

In the “FEM” view it is possible to import an external FEM model, to create a new

FEM model and to manage models.

[click]

The “Jnodes” view displays the “member” model with members and jnodes. If, and

only if, just one jnode is selected, it is possible to switch to the corresponding renode view.

[seleziona, click]

The “Renode” view displays a single 3D renode: here the user can manually add bolts,

welds, plates, angles, etc. but also assign one of the predefined parametric renodes of the

archive. Additional variables and conditions can be added too. Here, checks can be set and

executed, and their results can be shown.

[click, includi]

The “Solid” view, available in the FULL version only, displays the 3D view of the

whole structure after the construction of the renodes.

[vista renodo]


The alphanumeric view is available when the graphical view is in “renode” mode.

[callout] Three different panels can be displayed in the alphanumeric view: the “renode”

panel, the “selected components” panel and the “variables and conditions” panel.

The “renode” panel contains a list of all the components of the current renode.

Components are grouped by type. Sizes and data are given for each component. By double-

clicking components, they get selected.

[alcuni click membrature +, -, tramite, +, - unitori +, -]

The components that are currently selected in the scene are highlighted in the renode panel.

[click]

[click pezzi selezionati] The “selected components panel” contains the same

information of the renode panel. The difference is that only currently selected components are

displayed. The panel follows in real time the selection state of the scene. [alcuni click]

[click variabili e condizioni] All the predefined variables of the renode are listed in

the “variables and conditions” panel. If there are additional variables and conditions, they are

listed too.


402 INTERFACE: Buttons


[audio su immagini fisse]

FULL version

The interface of CSE FULL version has different toolbars containing buttons

associated to the most frequent commands: the upper toolbar contains commands belonging

to different menus, [pausa] on the left there are the commands belonging to the menus

“Renode” and “Checks”, [pausa] on the right there are the commands belonging to the

menus “Enquire” and “P-renode”.

When a button is grayed out, it means that related command is not currently available. For

clarity, none of the buttons is grayed out in this movie. Move mouse pointer on a button,

without clicking it, to know the name of the command.

The first buttons of the upper toolbar belong to the menu “File”, including “New”,

“Open” and “Save”. [pausa] The following buttons are the “Undo” and “Redo” commands.

[pausa]

Buttons for the management of the graphical view are available: they are mainly under the

menu “Draw”.

These buttons belong to the menu “Display” and are used to switch the modes of the

graphical view: FEM, jnodes, renode and solid view.

The buttons for units setting and for objects selection belong to the menu “Modify”.

The following buttons, under the menu “Checks”, are used to set current combination and

instance.

Last button is the “context sensitive help”: click it, then click a button or a command

in the menus to open the related page of the guide.

The buttons for enquiry are used to know distances or sizes, to find an object in the

FEM or Jnodes view and to get information on the FEM model.


The buttons of the menu “P-renode” are used to record, save and manage the parametric

renodes.

The first button of the left toolbar assigns a predefined parametric renode; the second

one resets the content of the renode. [pausa] Following buttons are used for the manual

creation and the management of the renode:

modification of the members;

addition of throughs like plates with generic shapes, angles and other components.

addition of bolt layouts;

addition of weld layouts;

copy of the components;

modification and removal of the components;

rotation and shift of the components;

work processes like cuts, bevels, etc.

automatic check for overlaps.

After the previous buttons, there are the buttons related to the commands for the

addition and the management of variables and conditions, including the guided “standard”

checks.

Remaining buttons belong to the menu “Checks”. After the execution of the checks there

are the commands used to display the results:

exploitation envelope, current exploitations, and exploitations enquiry;

bearing surface results,

members net sections results;

block tear failure paths;


results of the automatic FEM analyses

forces exchanged between the components

deformed views

output listing opening

LIGHT version

In the light version, the upper toolbar is quite the same; on the right there are only the

buttons for the enquiry, because the light version does not allow to save or manage the

parametric renodes.

Buttons on the left are bigger than in the FULL version and the toolbar contains only

the commands that are available in the LIGHT version. In addition, there is a button to define

the scheme of a typical node. With the LIGHT version it is not possible to add, shift, remove

or cut single components: it is only possible to apply one of the predefined parametric nodes.

In the LIGHT version there is also a button for the setting of the checks.


500 MENU: Overview


[audio su immagini]

1. FULL VERSION

An overview of CSE menus is shown in this movie. Each menu is then explained in a

pertinent lesson, where commands are briefly described. Finally, most of the commands have a

related movie to explain them in a detailed way.

File. It contains the commands to open, close and save a model; to start a new model; to save

current configuration; to manage prints; to capture the screen; to import and update an external

FEM model.

Modify. Contains undo and redo commands; the setting of current units, which can be modified

anytime; the settings for language, sounds, and members length in the renode; the commands for

objects selection.

Display. Contains the commands to manage some settings like fonts, colours, reference axes, sizes;

it is possible to hide or show the toolbar and the status bar; the graphical view can be set to FEM,

Jnodes, Renode or Solid mode.

Menu Draw. Contains the commands to manage the graphical view: zoom, pan, rotate, re-draw,

enclose, standard views, extract, etc.

Enquire. Contains the commands to get info about distances and sizes; to get information about

nodes, beam and truss elements in the FEM view; to the enquire internal forces in imported FEM

models; to get information about renode members whose gross-cross section is reduced due to bolt

holes, cuts, bevels, etc.; to find an object in FEM and Jnodes views.


FEM. Contains the commands to create a new FEM model or to manage an existing one; a special

tool guides the user to define a typical node quickly; in this menu there is also the command for

members search.

Jnodes. Contains the commands for the automatic search of the jnodes, for their management and

enquiry; it is possible to create and open the listing with full information about jnodes.

Renode. This menu contains all the “automatic” and “manual” commands to build and manage a

3D “real” node. It is possible to apply a predefined parametric renode of the archive, to add

components one by one or to mix the previous ways, applying a p-renode and then modifying it.

This menu contains also the commands to add and manage variables and conditions for user’s

checks and the commands for overlap and coherence automatic checks. It is also possible to export

the renode in dxf format.

Checks. Contains the commands to set and execute the checks and the commands to display checks

results (exploitation coloured maps, deformed views, exchanged forces, results on bearing surface

and members net sections, block tearing failure paths, opening of the automatic FEM models,

opening of the listing).

3D Model. Contains the commands to manage the 3D view of the whole structure. Commands are

available, but some tools have not been completely implemented yet.

P-renode. Contains the commands to record, save and manage parametric renodes, also called “p-

renodes”. P-renodes are renodes saved during the creation: they can be automatically applied to

other similar renodes; their sizes and data are given in parametric form, so they can fit different

sizes and alignments. CSE has an archive of typical p-renodes, but users can save new p-renodes

and manage the available ones, in order to get custom archives.

Window. Contains the commands to manage multiple views of the same model or different models.

Help. Contains the online help and the information about the program.

[salva audio della prima parte]


2. LIGHT VERSION

CSE LIGHT version has some limitations in the available commands and tools, so the

menus are reduced and simplified.

The menus File, Modify, Display, Draw, Enquire, Check, Window and Help are quite the

same, with the exception of few non-available commands in the LIGHT version.

Menus Jnodes, 3D Model and Prenode are not available because, in the LIGHT version,

related commands are not available or have been automated, like the Jnodes search.

Finally, in the LIGHT version, the menus called FEM and Renode in the FULL version, in

the LIGHT version have been grouped into a single and simplified menu called Nodes, because only

some of the commands are available.

In the LIGHT version it is not possible to define free structural schemes or build “custom”

3D nodes: with the LIGHT version it is only possible to define a typical node choosing it from the

available ones, and then apply to it a predefined parametric node from the archive.


501 MENU: File


[deve esserci un renodo in vista grafica attiva]

The menu “File” contains the following commands.

New starts a new model.

The command Open is used to open a file saved on a hard-disk, on a removable drive, on a CD-

ROM or in a network. [click]

Close: this command closes the active window. If the model was not saved after the last operations,

the program asks to save these changes.

Save: this command saves the operations done on current model.

Save as saves current model with a different name, chosen by the user. Original model won’t be

modified.

If the FEM model has been imported from Sargon or SAP2000, a copy of related output files is

automatically made: so, the model saved with a new name keeps alive all the information about

combinations and internal forces in beam and truss elements.

The command Save configuration saves current settings, like language, fonts, colours and sizes of

the objects, etc. Settings are saved in the file named “cse.sts”, in program installation folder.

Print: this command prints active view. Some information is added to the printings, like date and

time, copyright, user’s name and other notes

Print preview displays a preview of what is going to be printed. [click]


Print set up is used to set print options.

Title: can be used to add a title to the printings. To remove a previous title, use this command and

leave the box blank. [click]

Photograph: this command is used to copy the content of the active view to the clipboard, in order

to paste it into software supporting bitmap format, like Word, Write, Excel, Paint, etc.

[esempio: incollare vista grafica in paint]

Calculator opens Windows Calculator.

The commands Import FEM model and Update FEM model are explained in movie 600, because

they need a more detailed explanation.


502 MENU: Modify


The command Undo erases the last changes done on current model, with a maximum amount of 10

operations.

The command Redo reverts the effects of a previous Undo.

The command Units is used to change current units. It is explained in movie 610.

The commands of the sub-menu Select are explained in movie 611. They are used to select objects.

The command Settings is explained in movie 612. It is used for general program settings.


503 MENU: Display


The Toolbar command hides or displays the toolbar.

Status bar hides or displays the status bar.

Reference axes manages the settings for reference axes display. [click] It is possible to display the

axes in the standard mode, to display them in the origin or to hide them.

The Fem command sets the graphical view to FEM mode. Here a FEM model can be created,

imported of modified.

The Jnodes command sets the graphical view to Jnodes mode. Here members and jnodes are

displayed after their automatic search. When a single jnode is selected, it is possible to switch to

related “renode” view.

The Renode command sets the graphical view to Renode mode. The renode is the “real” 3D node.

In this view it is possible to assign a predefined complete node or to add cleats, bolts, cuts, bevels,

etc. in a free way. This command is active if and only if, one and only one jnode is selected.

The Solid command sets the graphical view to Solid mode. Here the complete 3D structure can be

displayed, including bolts, welds, cleats, etc.

The Orientation command is explained in movie 620. Local axes of components are displayed.

The Modes command is explained in movie 621. It defines some display settings for the graphical

view.

The Sizes command changes the sizes used to display objects. [click] It is possible to change the

size of nodes and jnodes symbols, of end-releases and constraints, the thickness of trusses, beams


and members in FEM and Jnodes views, the size of exchanged forces in 3D real node, etc. Settings

can be changed in order to improve prints, screenshots, displays, etc.

The Objects command is explained in movie 622. It controls the addition or removal of special

symbols and labels.

The Colours command is used to change default colours used to display objects and symbols.[click,

sfondo grigio]

The Font command is used to change font type, size and colour of printed numbers and labels.

[click]

The Scene points command is explained in movie 623. It is used to display 3D scene points.

Changes to the settings can be saved with the command File – Save configuration.


504 MENU: Draw


[TT013.CSE; vista renodo, zoom che non include tutto il collegamento]

Most of the commands of Draw menu have a button in the toolbar. [callout]

The Redraw command refreshes the graphical view. Use this command in case of overlapping

hidden lines and overlapping or missing highlight points.

Enclose is a useful command that includes the whole structure in the screen, automatically setting

the zoom level. [click]

Pan: this command is used to shift the view box. User defines a shift vector clicking two points

with the mouse or with “enter” key. The graphical view is shifted after the click of the second point.

Use ESC key or mouse right button to end the command, otherwise click two other points to define

another shift. [esempio]

The commands called Pan up, Pan down, Pan right and Pan left shift graphical view box one

click up, down, right or left. Use the buttons in the toolbar to quickly use these commands. [click]

The Zoom in command is used to enlarge a part of the graphical view: after command execution,

user clicks two points in the graphical view in order to define a rectangular box having the same

aspect ratio of the window. This box will be enlarged including it in the full graphical view.

[esempio]

Zoom in Click: this command enlarges the view with a click. [esempio]

Zoom out and Zoom out Click work similarly to previous commands, but they reduce the view

instead of enlarging it. [esempi]


Zoom last: this command resets last zoom.

Standard view opens a dialog box where the user can choose one of the predefined views. [click,

scegli una vista]

Current standard view works as previous command, but the view is now set in current reference

system instead of the global one.

The Remaps command opens a dialog box where user can define a new point of view. [click,

cambia vista] [usa ancora il comando] It is also possible to define the vector of the new view in

numeric form, by clicking any keyboard key. [premi tasto, cambia un numero, OK]

Use Rotate anticlockwise and Rotate clockwise to rotate the view anticlockwise or clockwise on a

horizontal plane. Rotations have 15 degrees clicks. Vertical view-vector component is unchanged.

Use Rotate up and Rotate down to rotate the view up or down on a vertical plane. Horizontal

view-vector component is unchanged.

Use the buttons in the toolbar to quickly define rotations.

The Extract command is used to extract some objects hiding the other ones. Select needed

components and execute the command. [selezione di qualche componente, estrai selezionati]

When the extraction is active, use the command again to get back to standard mode.

[vista fem]

The Alignments command is used to define alignments for the FEM view; an alignment is the

equation of known plane. See the guide for more information about this command.


505 MENU: Enquire

revisione PR marzo 2012

[modello Cmd_Interroga_Az_int_travi.CSE in vista fem, un renodo aperto in un’altra finestra in

primo piano]

The Enquire menu contains the command used to get information about the FEM model

and about the net sections of real node members. There is also a command to find objects in FEM

and jnode view using their ID.

The Geometry command gives information about the distance between FEM nodes, jnodes,

or points in the 3D real node. [eseguire comando] Click a point: [click] its coordinates are reported

in the first row. Now move mouse pointer towards another point: [muovi] the nearest point is

reported in the second row; Distances are given in the third row. If you click another point, it is

reported in the first row, an so on… [muovi] Click mouse right button or ESC to end the

command.

[passa a finestra con modello fem]

In the FEM view, and similarly in the jnode view, the Geometry command can be used to

get the distances between nodes. [esempio]

In FEM and jnode views, the Find command is used to find some objects using their ID.

[click]

In this dialog box, choose the kind of the element and type its ID. For example, beam

element number 1 in FEM view, or Jnode “AB” in jnode view, etc. [trave 1, OK] Beam number 1

has been found, highlighted with a red circle, and selected.

The Nodes command gives information about the nodes of the FEM model. [click] Just

move mouse pointer on the chosen node or click it to stop mouse moving sensitivity. If you don’t

click any node, current nearest node to mouse pointer is reported. [click] Among the other data, the

following are available: geometry; constraints. [click]

The Trusses and Beams commands give information about FEM model trusses and beams.

For example, execute Beams: [click] like for the nodes, click an element to fix it or just move


mouse pointer towards it [click] Click mouse right button or ESC once or more times to end the

command. [esc]

Information about connectivity, [click] end releases at the extremes, [click] cross-section,

[click] material, [click] offset [click]and orientation is given. Click mouse right button or ESC once

or more times to end the command. [esc]

For the trusses is the same, but some information is not available: trusses are hinged by

definition, so information about end-releases is useless; trusses do not have offsets.

Cross-sections and Materials commands provide information about the cross-sections and

the materials of current FEM model. They are available in FEM view only.[pausa, mostra]

Internal forces - beams gives information about internal forces in beam elements of an

imported FEM model, if this model has available results and if combinations are active (use proper

commands in FEM menu to set active combinations). After the execution of the command, a dialog

box is opened. [click] Click an element: a circle is displayed on it, [click] move mouse pointer

along the element to display in the dialog box the internal action in a given point. Data in the dialog

box are updated in real time. The following data are given: element number; distances along

element axis (dimensional and non-dimensional); internal forces (axial force, shear forces,

moments).

Click mouse right button twice to get back to the choice of another element, click it thrice to

end the command. ESC key can be used instead of mouse right button. [interrompi]

Internal forces – trusses works in the same way. The only difference is that trusses have

axial force only.

The Net sections command is explained in movie 630.


506 MENU: Fem


[modello qualsiasi in vista fem, menu aperto]

The FEM menu contains the commands for the creation or modification of a finite element

model.

It is possible to define Typical nodes with a quick automatic tool.

[img]It is possible to manage the nodes with the commands Modify and Delete.

[img]It is possible to

add and delete beam and truss finite elements,

define their orientation, material and cross-section

assign offsets, reset offsets and assign automatic offsets with the Snap over locus command.

[img]Proper commands are used to assign end-releases and constraints.

Note well: import and updating of external FEM models are managed by commands under File

menu.

[img]There are also commands used to manage combinations (Combi set and Select

combinations).

Finally, there is a command for the automatic search of the members.


All these commands are explained in proper movies.

[15-20 secondi di filmato muto per callout]


507 MENU: Jnodes


[modello qualsiasi in vista jnodi, menu aperto]

The Jnodes menu contains the commands for the automatic search of the jnodes, for their

enquire and for their management; there are also commands for the automatic creation and opening

of jnodes listing and one command for the extraction of selected members in jnode view.

These commands need detailed explanations and are shown in proper movies.



508 MENU: Renode


[vista di un renodo qualsiasi, menu aperto]

The Renode menu contains the commands for the automatic or manual construction of the

real 3D nodes and for their management. It is possible to apply an already prepared parametric real

node of the archive or to add components one by one (like bolts, welds, plates or other kind of

cleats, etc.) with free positioning of the objects.

It is possible to add new variables and conditions using predefined variables, in order to

define user’s additional checks. CSE will automatically check these additional conditions.

Commands for overlap and connections coherence checks are available too.

It is also possible to export current renode in dxf format, for Autocad or similar programs.

These commands need detailed explanations and are shown in proper movies.



509 MENU: Checks


The Checks menu contains the commands for the setting and the execution of the automatic

checks and the commands to display and manage the post-process.

Check settings include the choice of a Standard, the choice of combinations to be used, the

choice of the different checks to be performed, the output listing settings, etc.

Post-process commands include exploitation envelope coloured maps, exploitation enquiry, block

tear results, members net sections results, FEM results, deformed views, bearing surface results, etc.

All the commands of this menu need detailed explanations and are shown in proper movies.


510 MENU: Window and Help


[renodo qualsiasi]

The Window menu manages multiple windows of the same model or different models.

New window opens in current CSE instance a new window of the current model. It is

possible to have different windows of the same model, for example, the FEM model in a window, a

3D node in another window, the results on bearing surface in another window, etc. [click]

Overlapping places all the windows one above the other (window can belong to the same

model or to different models). [click]

Tile displays all the windows at the same time, resizing them. [click] Click into a window to

activate it.

Arrange icons aligns the icons of all the windows. [riduzione a icona, spostamento casuale,

comando “Disponi icone”]

The Help menu contains the following commands:

Guide TOC opens the table of contents with CSE guide. [click – scorri argomenti]

About CSE gives information about the license and the current version. [click]

Note well: use this button [click] and then click another button or a command from the menus to

open the guide TOC directly to the page of desired command. [esempio]


511 MENU: Prenode


[modello con renodo vuoto, menu prenodo aperto]

The P-renode menu contains all the commands needed to record a new parametric renode

and to manage the available p-renodes of the archive.

The commands of this menu have a toolbar on the right. [callout]

A “p-renode” is a parametric, real node. A p-renode can be saved and applied later to other

similar nodes, which can differ in some sizes or in some properties.

CSE has a wide archive of predefined p-renodes, but each user can save his own p-renodes

adding them to the archive. In addition, users can modify predefined p-renodes.

New starts the recording of a new p-renode.

Restart is used to record new operations adding them to an existing p-renode.

Add image adds a new image to current p-renode.

Pause and Continue are used to pause the recording and the to continue it.

Save saves current recording into the archive.

Abort exits from the recording without saving it.

Archive is used to manage the archive: it is possible to delete p-renodes, to modify their images

and descriptions, to duplicate them, to save the archive in text format, etc. It is also possible to

modify the operations of each p-renode editing an alphanumeric text.

The commands of this menu need detailed explanations and are shown in proper movies.

[callout finale che rimanda ai filmanti dei comandi]


512 MENU: Nodes (light version)

revisione PR marzo 2012

[light version]

The Nodes menu is available in the light version only. It contains some of the commands of

the menus called FEM and Renode in the full version. These two menus contain some commands

that are not available in the light version. The remaining available commands have been grouped

into a single, simplified menu called Nodes.

The command Typical nodes is the only one belonging to FEM menu in the full version. It

is used to define the structural scheme and assign material and cross-sections in a guided way.

All the other commands belong to Renode menu in the full version; they are used to apply

and manage the predefined parametric nodes of the archive.

The commands belonging to Node menu of the light version are explained in proper movies.



600 COMMANDS: FILE – IMPORT FEM MODEL, UPDATE FEM MODEL revisione: gennaio 2012

[modello vuoto; importazione di Cmd_File_Importa_Aggiorna.WSR]

CSE interfaces directly with the finite element programs Sargon and SAP2000; complete

finite element models of the internal forces in all defined checking combinations can be imported

into CSE from these systems. FEM models created using programs that support the sr3 format can

also be imported into CSE.

[callout: Sargon, prodotto e distribuito da Castalia srl; SAP2000, prodotto da CSI e distribuito in

Italia da CSI itala]

The command to import a FEM model is Import, on the File menu. The command is

available when the graphical view is active and the current model is empty. [click] We select the

directory where the model to be imported is held (in this case, a Sargon model with file extension

wsr), and we open it. [click]

The model is immediately imported into CSE: as well as the geometrical properties, the

sections and materials, the constraints and end releases, there are also all the checking combinations

defined in the original model; each of them contains the internal forces in the various elements

computed using static or dynamic analyses.

When a model is imported, the system also automatically searches for the members

according to criteria such as alignment, element type, orientation, continuity of section and material,

end releases, connection codes, and so on. These issues are discussed in the lesson about finding

members. The members can be seen in the JNode view. [ vista jnodi]


If we import a SAP2000 model, then the computer we use must be installed with a working

copy of the latest version of SAP2000. This is because CSE runs SAP2000 to import – and solve –

the FEM model.

When using a finite element program that supports the sr3 format, we must export the

desired model in the free sr3 format before importing it into CSE.

[selezione dei nodi dell’ultimo piano nel modello fem, traslazione z=+500mm, salvataggio]

With the Update command, which is available in the graphical view, we can avoid having to

go back and import again when the original model has been modified; in this way, we can retain all

the work already done in CSE that can be saved.

It is good practice to analyse the connections in CSE only when the FEM model has been

finalised, with the definitive geometry, loads and internal forces.

Clearly, though, all the work on the connections need not be lost because of some small

changes to the FEM model.

Whenever JNode topology is modified, however, the work processes will always be lost

from the real nodes, or Renodes, associated with the JNodes concerned; such modifications include

altering or re-orienting a section, changing angles, or deleting or adding an element. The other

Renodes will not be affected.

For example, if the checking combinations in the original model are reworked, then no

JNode will be affected topologically, and all the Renodes will be maintained. Replacing a HEB

section with a HEM, on the other hand, will cause the work processes applied to all the Renodes

involved to be lost.


When the Update command is run, the system prompts for the reference FEM model. The

model is opened and compared with the version previously stored in CSE. The members will be

searched for again, the JNodes will be updated automatically, and all the Renodes that can be

preserved will be. [click]

In this case, the nodes in the starting model for the last floor slab have been translated

upwards. Any work processes applied to the nodes shown would be lost, because the axis of their

diagonals changes, and that could alter the constraints.

Users should take great care when using this command, to ensure they properly understand

the impact that the changes would have on the JNode topology, before modifying the model.


610 COMMANDS: MODIFY – UNITS revisione: dicembre 2011

To modify the units of measurement, we use the “Units” command. This is available on the

Modify menu and as a toolbar button. [callout].

When the command is run, a dialog box appears for the user to select the units of

measurement for the lengths, forces, and (if required) temperature.

The units can be changed at any time. All data input to the program must be in the current

units, while the quantities output by the program are also expressed in the current units.

The current units are shown at the bottom of the graphical view. [callout]


611 COMMANDS: MODIFY – SELECT revisione: dicembre 2011

The commands for selecting and unselecting objects can be found in the “Modify” menu.

They are also provided as buttons on the toolbar.

In this video, we will be referring to “changing an object’s selection status”: this means

selecting a currently unselected object, or vice-versa.

Objects are selected and unselected in different ways according to the current graphical

view.

FEM VIEW – JNODE VIEW

The selection commands act on either the dimensionless elements (nodes of the finite

elements or JNodes, according to the view involved) or the wireframe elements (finite elements or

members, according to the view); currently, we are in dimensionless-element mode, which in this

view – the FEM view – concerns the nodes.

The “Select all” command selects all the nodes, while “Unselect all” unselects them all. The

currently selected nodes are shown with a small dark blue box (the colour can be changed in the

settings).

With the “Select-Click” command, we can change the selection status of an element, simply

by clicking on it with the left mouse button.

“Select by box” and “Select by polygon” change the selection status for all nodes inside a

box or polygon defined by the user. The box is defined as a rectangle by specifying two opposite

vertices. […] For the polygon, each click specifies a new vertex, and the definition is completed

with a double click.


If we activate wireframe-element selection mode, the commands that we have just seen can

be used on the finite elements. We need to click near the axis of an element; the box and the

polygon change the selection status of all the elements that have both their nodes inside the closed

line.

In JNode view, the objects are selected using the same means as in the FEM view, except

that the distinction when running the commands is now between JNodes and members, as opposed

to nodes and finite elements. […] When a JNode is selected, so are all the instances associated with

it.

RENODE VIEW

Because Renode view contains three-dimensional objects only, there are no selection filters

for different dimensions.

The “Select all” and “Unselect all” commands work exactly as in the FEM and JNode

views.

When selecting via mouse click, we change the selection status of the element pointed at by

the mouse cursor.

When selecting via box or polygon, we change the selection status of all objects contained

entirely within the closed line specified.

In Renode view, the selection status can be changed for components as well, using the

“Renode” panel in alphanumeric view: double-click on a component’s name to select or unselect

that component in the scene.


612 COMMANDS: MODIFY – SETTINGS revisione: dicembre 2011

The “Modify settings” command, on the Modify menu, is available when the graphical view

is active. [click]

The length of the member stumps shown in Renode view can be modified. The length must

be expressed in the active units of measurement; to be effective, changes to this parameter must be

made before JNodes are searched for.

The sounds that represent correct insertion or that alert to overlaps between components can

be deactivated, if desired.

We can specify a minimum size (in the current units) for a four-sided face to be considered

boltable by CSE when it searches automatically for the bolting levels.

If at least two of the face’s sides are shorter than the specified limit, the face will be

discarded by CSE as unboltable. This parameter can be edited at any time; new bolt layouts are

added based on the current settings.

An external finite element program can be set up to create and solve the automatic FEM

models of the components. The directory containing the application to be used, along with the

application itself, must be specified in the box provided.

Finally, the language used for the CSE interface can be changed, to have all the menus,

dialog boxes, commands and messages appear in the preferred language.


To change language, select the language desired [click inglese], click OK […] and, when

prompted by the system, run the File-Save configuration command, exit from CSE and relaunch the

application. […]

CSE will restart in the selected language. [riapri]


620 COMMANDS: DISPLAY – ORIENTATION revisione: dicembre 2011

The “Display orientation” command is available from the “Display” menu.

The orientation can be shown for all the objects in the scene, for none, or for the currently

selected ones only. The size of the local axes displayed can be altered.

The FEM and JNode views offer three ways of seeing the orientation; Renode view offers

two.

FEM AND JNODE VIEWS

In the FEM and JNode views, users can choose between the following representations, all of

which correspond to the midpoint of the beam or member, depending on the current view:

- synthetic representation: only local axis 2 for the elements is shown; […]

- complete representation: the full set of three local axes for the elements is shown; […]

- detailed representation: the elements’ cross-section is shown. […]

RENODE VIEW

In Renode view, a detail view would be meaningless, as the form of the three-dimensional

objects can already be seen. The complete and the synthetic representations can still be used. For

example, let’s look at the complete representation for the elements selected only.


Presently, no objects are selected, and no orientation is shown.

If we change the objects’ selection status, the representations of the orientations are updated

in real time.

For bolt and weld layouts, the orientation of the entire layout is displayed.


621 COMMANDS: DISPLAY – MODES trascrizione/revisione: gennaio 2012

[renodo semplice, costruito]

Using the Modes command, on the Display menu [click], the user can select the means of

representing the finite elements in FEM view and the components in Renode view (in the real three-

dimensional node).

The finite elements can be represented in different colours depending on their section… the

material… the type (beam or truss)… the group they belong to… the maximum slenderness… the

slenderness in terms of bending about the two pricipal axes… , or all in the same colour.

The user can choose whether to display the Renode’s components in different colours

depending on their identification number... to display them all in the same colour... to display them

according to their type (member or force transferrer/cleat)... or to display them all in white.

Joiners – bolts and welds – are always shown in grey.

We’ll now display the components in the node according to their type [click, ok]. The

members are displayed in green; the force transferrers/cleats, in light blue.

Now here are the components all in the same colour. [click]

Finally, we can show the components by number [click, ruota vista]. Member 1 and force

transferrer 1 have the same colour, as do member 2 and force transferrer 2.


If we run the File–Save configuration command, CSE will save the changes to the settings

as the new default.


622 COMMANDS: DISPLAY – OBJECTS trascrizione/revisione: gennaio 2012

[renodo con tre finestre affiancate, FEM – jnodi – renodo]

Using the Objects command on the Display menu [click], we can decide which objects to

show and which to hide in the various views.

In the Objects tab, we choose whether or not to show the nodes, end releases and constraints

in the FEM view; we specify whether the JNode view is to show all the JNodes present or just those

selected; in the Renode view, we can display the names of members, force transferrers/cleats, bolt

layouts and weld layouts. [click]

In the Numberings tab, we can choose whether to display numberings: for nodes, beams and

trusses in the FEM view; for members in the JNode view; and for bolts and welds in the Renode

view. [click]

In the Labels tab, we choose whether to display the section and material labels in the FEM

and JNode views.

When we click OK, the settings are applied. If we run the command File–Save

configuration, CSE will save these settings as the default.


623 COMMANDS: DISPLAY – SCENE POINTS revisione: dicembre 2011

[modello Cmd_Verifiche_Risultati.CSE, vista y; dimensione punti: 2]

The “Scene points” command is available from the “Display” menu and as a toolbar button,

and it can be used when Renode graphical view is active.

This command is used to create and display the significant points needed on the components

in the scene. The points created are also displayed if the box on the left is ticked; these points will

have the size specified [arrow callout]. If we choose not to display the points, then they will be

clickable but not visible.

In the panel on the right, we select which points are to be created. The significant points

available are: the midpoints of the sides on the faces of all components present; […] the points at

one-third and one-quarter intervals along the sides […]; the centres of all the faces; […] the position

of the theoretical FEM node; […] the points at equal intervals along all the sides, starting from the

vertices, at the step distance specified in the field provided, in the active units of measurement. If

this value is zero, then no equally spaced points will be created; to reset the value to 0, simply click

the button alongside.

All the significant points can be created at once, although the best way to use this command

is to concentrate only on those that are actually necessary each time. As an example, let’s create and

display the points at one-third intervals along the sides [applicare la scelta].

The various different types of point are displayed in different colours, which are

customisable via the “Display – colours” command. If we are working in extract mode, only the

points on the currently extracted objects will be shown.


All vertices are always displayed, in addition to the selected points.

The significant points can be used in all commands that require points in the scene to be

clicked. They can therefore be very handy when adding a force transferrer/cleat, for example, or

when specifying a component copy or translation in “face-point” and “two points” modes.

With the Enquire-Geometry command, these points can be clicked to find out the distances

from other points. [mostrare un’interrogazione]

When work processes are set up that involve removing a prism, significant points need to be

defined in the work process dialog box. If some points have been displayed using the “Display

Points” command, then they are hidden while the work processes are applied. They become visible

again once the work process has been completed.


630 COMMANDS: ENQUIRE – NET SECTIONS revisione: dicembre 2011

[renodo Cmd_Interroga_SezioniNette.CSE]

Members may have reduced gross sections, due to bolt holes or various work processes like

cuts or bevels. CSE systematically examines all the members and identifies the net sections: these

are the sections that are smaller than the gross section.

The user can look at the net sections found by CSE, using the Enquire net sections

command. This can be found in the “Enquire” menu and is accessible when the Renode view is

active and one (and only one) member is selected.

[click] When the command is run, a dialog box appears showing all the net sections that

CSE has found. If no net sections exist, then the dialog box will be empty; otherwise, the first net

section is displayed.

Below the image, the total number of sections found is reported; under that, there is the

number of the current section and its distance from the member’s theoretical extremity. We can

browse the sections using the arrow buttons. [click]

CSE examines the sections along the member’s axis and identifies a net section at the centre

of every bolt hole that it finds. Where several bolts are in a line, the program returns a single

section. Where bolts are close together but not aligned, the section corresponding to the centre of a

hole will also show part of the other hole – just like when sectioning the entity physically.

CSE also identifies net sections where the cross-section is different due to the removal of

material, through cuts, bevels, etc.

Under the figure, the area and the section moduli for the current net section are shown.

These are compared with those of the gross section. Note that we are dealing with different sections,


so the moduli are significant only if the net section’s principal axes have the same orientation as

those of the gross section.

Using the “Copy” button, we can copy the image of the current section to the clipboard and

paste it into documents, calculation reports, etc. The “Print” button sends the image for printing.

The “Section data” button [click] leads to a dialog box with detailed information about the current

section.

In this example, we have used an IPE section; the command also works with more complex

sections, like generic cold-formed ones.

[passare a modello “artigianfer” work(2).CSE e far vedere la sezione netta]


640 COMMANDS: FEM – NODES revisione: dicembre 2011

Nodes can be managed using two commands on the FEM menu, under the Nodes sub-menu.

They are available when the graphical view is active in FEM mode.

The “Delete” command deletes all unreferenced nodes, i.e. all those with no finite element

attached to them.

The “Modify” command [click] brings up a dialog box where the user can manually edit

each node’s coordinates and constraints. Unreferenced nodes can be deleted from here too.

The first 6 nodes are completely constrained nodes at infinity that are needed to define the

orientation of the finite elements.

Nodes 7 and onwards have been added by the user.

For example, we can change one of the coordinates of node 7. We can release its rotations,

which are currently blocked. Zero means that the degree of freedom indicated in the corresponding

column header is not constrained.

… the node’s position in the scene has been modified, and now the constraint is no longer a

clamp but a hinge.


641 COMMANDS: FEM – ELEMENTS – PART 1 OF 3 revisione: dicembre 2011

[modello nuovo; preparativi: aumento spessore travi, mostra orientazione sintetica selezionati]

[callout parte 1 di 3 AGGIUNGI, CANCELLA, ORIENTAZIONE]

Finite elements can be added and managed using commands on the Elements sub-menu of

the FEM menu; they are available when the graphical view is active in FEM mode. Let’s take a

look at them one by one.

ADD

When the Add finite elements command is run, a dialog box appears for the user to specify

whether to add beams or trusses.

So we need to decide what to use as the third node for the beams that we are going to add.

The third node can be any of the nodes already present in the FEM model; in particular, 6

predefined constrained nodes at infinity are always available for this purpose. These predefined

nodes are:

node 1: node at infinity in the +y direction

node 2: node at infinity in the +z direction

node 3: node at infinity in the +x direction

node 4: node at infinity in the -y direction


node 5: node at infinity in the -z direction

node 6: node at infinity in the -x direction

The third node identifies the element’s 1-2 plane: indeed, local axis 3 is defined as the vector

product of the local axis 1 and the vector consisting of “the third node minus the element’s first

node”.

The command can be used in two different modes. In the first (known as “single mode”), the

user adds a series of elements that generally do not share any common node (one element here, one

there, etc.). In the second mode (“multiple mode”), the user adds a series of beams so that the first

node of each beam (after the initial one) coincides with the second node of the previous one. We

will be using single mode.

[ok]

We press the space bar to access the dialog box for inserting the first node of the first

element. We define the node’s coordinates, in the current units (in this case, millimetres).

We press the space bar again to insert the second node. Now we need to define the

coordinates of the second node relative to the first one: we will move 2000mm in the z direction.

We now click on one of the nodes, to make it the first node of the next element.

We press the space bar to define the coordinates of the second node relative to the first one:

we will move another 2000mm in the z direction.


To insert a horizontal beam, we click on the central node, press the space bar and define a

second node at -2500mm from the first one in the x direction.

We now have the wireframe geometry of a beam-column connection. Press ESC or click

mouse right button to end the command.

DELETE!

The “Delete!” command immediately deletes all the selected finite elements. If this leaves

unreferenced nodes, then these will be retained (please see the lesson about working with nodes).

ORIENTATION

[selezionare due elementi verticali]

The “Orientation” command can change the orientation of the currently selected elements in

3 different ways:

by defining a third node to replace the one previously assigned;

by defining the three components of a vector that identifies the 1-2 plane of the element’s local

axes: local axis 3 is effectively the vector product of axis 1 and the vector defined;

by defining the three components of a vector that identifies the 1-3 plane of the element’s local

axes: local axis 2 is effectively the vector product of axis 1 and the vector defined.

For example, we can assign third node 3 (at infinity in the +x direction) to the currently

selected vertical elements, so as to rotate them by 90°.


[callout: fine parte 1 di 3]


642 COMMANDS: FEM – ELEMENTS – PART 2 OF 3

[callout parte 2 di 3: SEZIONI, MATERIALI]

[visualizzare etichette sezione e materiale]

CROSS-SECTIONS

Using the “Cross-sections” command, we can assign the cross-section we want to the

currently selected elements, by choosing one of the over-10,000 sections in the archive. Using the

SAMBA software package, we can further expand the archive by adding new sections to suit user

requirements. The sections can be composite, welded, rolled and cold-formed, in a whole range of

different shapes. Cross-sections can be also added directly in CSE. Now we browse the archive.

[click]

We can filter the sections by ticking the boxes representing the types that we want; we can

also search by name, by the limits that the sections must obey, and by design criteria. The various

filters can be combined.

For a detailed description of them, please see the user guide or the online help.

[callout: premere F1 per visualizzare direttamente la pagina dell’help relativa all’argomento –

solo dopo aver sistemato HIDD_ nell’rtf]

The “Archive” button brings up a list of all the sections in the archive that meet the filter

criteria specified; if no filter was used, then we get the entire archive. The sectional properties are

expressed in the current units of measurement.


Clicking on “Model” gives us a list of the sections that have already been used in the model,

which may be assigned to the currently selected elements.

We want to assign a HEB section to the column, so we tick the corresponding box. We bring

up the archive and select a HEB 220 section. When the figure is clicked, a dialog box appears with

additional information about the section and its properties.

When we click Apply, the chosen section is assigned to the currently selected elements. The

section can also be rotated by an angle of our choosing before we insert it.

The “Materials” command brings up a dialog box from which we can choose one of the

materials already present in the model. Alternatively, we can use the “Archive” command to select

a material from the CSE archive, which can be further extended using the SAMBA software.

Before accessing the archive, we can filter by the reference standard, by the yield stress or

by the ultimate stress.

We will choose S235 steel and apply it to the selected elements. Its properties are shown in

the current units of measurement.

[OK]



643 COMMANDS: FEM – ELEMENTS – PART 3 OF 3

[callout parte 3 di 3 ECCENTRICITÀ, SNAP SU LUOGO, REIMPOSTA ECCENTRICITÀ]

The commands “Offsets”, “Snap over locus” and “Reset offsets” can be used to manage the

rigid offsets at the beam elements’ extremities with respect to the nodes. Offsets affect the

distribution of forces in the model and make it possible to define suitable alignments between

members and to avoid overlaps between solid objects. This helps us prepare the connections

effectively and reduces the need for work processes during the subsequent construction of the three-

dimensional Renodes.

The “Offsets” command brings up a dialog box where offsets can be specified as absolute

values or as increments relative to existing offsets [callout arrow]; they can be defined either in the

global reference system or in each element’s local system. [callout arrow]

Working in manual mode, we then click on all the extremities in the scene to which we want

to apply the offset; in automatic mode, when the OK button is clicked, the offsets defined will be

applied to all the extremities previously selected. An element’s extremity is selected if both the

node and the beam element associated with the extremity are selected.

By means of the tick boxes, offsets can be applied only in the directions desired, with

magnitudes as set in the associated fields.

For example, we can assign an absolute axial offset manually in the global reference system

at the extremity where the horizontal beam meets the column, so that there is no overlap.

Let’s set the offset in the x direction to –110mm, which is half the height of the column

section,…


… and then click in the scene on the beam extremity.

The black segment represents the rigid offset; the element’s axis is now shorter. It is, of

course, possible to define offsets normal to an element’s axis and to assign different offsets to the

two extremities of the same element.

Press ESC or mouse right button to end the command, otherwise click a different extremity

to add another offset.

With the “Snap over locus” command, the user can take all the currently selected elements

and assign offsets (to both their extremities) that are normal to the element’s axis, defined

automatically to make a selected point in the section lie on a plane specified by the user. The

command can therefore be used only on a beam element that has been allocated a cross-section.

Every section has four significant points called the Top, Bottom, Right and Left of Steel. For

a definition of these terms, please refer to the user guide or context-sensitive help (simply press F1

when in a dialog box to access the help page about it). [premere F1]

The plane must be defined in the form ax + by + cz = d, using coefficients a, b, c and d.

Planes that have already been defined using the “Alignments” command can also be used.

When we click OK, CSE computes and assigns the offsets so that the chosen point in the

section for all selected elements lies in the specified plane.

[con elementi verticali selezionati]


Suppose, for example, that we want to give the column an offset of 20mm in the x direction:

we define a plane x=130 (which is half the height of the section, 110, plus 20mm) and specify that

the Top of steel, the outside of the upper flange, should lie on it.

[input: 1 0 0 130 OK]

If we inspect the offsets of the beam elements, we see that CSE has added 20mm rigid

offsets in the x direction.

[selezione di tutte le membrature]

The “Reset offsets” command resets the offsets of some beam elements in the model by

deleting the offsets previously defined for them. The offsets are applied subject to the following

conditions:

a) the element must belong to a “slave” member of a hierarchical JNODE;

b) all the finite elements making up the member must be selected, so that the member itself can

be considered selected.

The command starts by analysing the finite element model and transforming it in the

background into a member model. This operation depends on certain properties of the model,

namely:

· the orientation of the local axes;

· the assignment of the sections and materials;

· the presence of end releases or connection codes without end releases;


· the nature of the elements (beams or trusses).

For a detailed description, please see the user guide or online help.

Essentially, the selected beam-type slave elements belonging to a hierarchical JNode are

interrupted with axial offsets calculated as a function of their respective orientation relative to the

master.


645 COMMANDS: FEM – TYPICAL NODES

[versione FULL, nuovo modello, vista fem attiva]

LASCIARE QUALCHE SECONDO DI PAUSA The command “typical nodes” under

“fem” menu is available when graphical view is active, in fem mode and empty. This command is

used to automatically create a fem model of the node we want to study.

After the execution of the command, we can choose a structure among the available ones.

There are: splice joints; beam-columns joints; beam-beam joints; ground joints; bracings;

nodes of lattice structures.

Some structures need the definition of some sizes to fix the geometry of the scheme. Those

sizes are shown in the images.

Now we are going to choose a beam-column joint. PAUSA DI 2-3 SECONDI [cliccare

primo schema trave-colonna]

The properties of the joint must be defined in this dialog box.

We can add a new material… PAUSA DI 2-3 SECONDI [click aggiungi, esc] … or choose a

material from the archive. [click archivio]

Apply the S235. [click] Chosen material is reported in the proper box.

We can also define new cross-sections… PAUSA DI 3-4 SECONDI [click, aprire una

sezione, chiudere] … or choose a cross-section from the archive.[click archivio]

Set a filter on cross-section type, for example HEB, before browsing the archive. [spunta la

casella] Click this button to see all the HEB sections of the archive. [click]


Apply the HEB200. [seleziona e applica]

Chosen section now is the “current” one: it is possible to apply it to the members of the

joint. This button assigns current cross-section to member 1, which is the “master” member of the

node. The master, a column in this case, is shown in red in the image. [click assegna]

Now apply an IPE cross-section to member 2, the slave of this node. PAUSA DI 3-4

SECONDI [assegna IPE220]

If the ticks on “strong axis” boxes are removed, a rotation of 90 degrees is applied to the

cross-sections. For slave members it is possible to define hinge connections to the master.

If we remove the tick at the bottom and press OK, the fem model will be created but

members and jnodes won’t be automatically found. The search must be done by the user, who can

also modify initial fem model with the addition of new elements, the shift of some nodes, etc.

If we keep the box ticked and press OK, members and jnodes will be automatically found.

[click OK] With the full version it is possible to add other nodes; now just click NO and go on.

[click]

Check settings are not explained in this lesson. They can be defined now but also later. Just

keep current settings. [click]

Graphical view automatically switches to renode mode, and 3D node is shown. This “blank”

node is ready for a manual addition of components or for the automatic application of a predefined

parametric renode.

STOP – SALVA AUDIO nome file: _ENG621_aud_01

NUOVA REGISTRAZIONE


In CSE light version, “typical nodes” command is under the menu called “nodes”. A button

is available in the bar. [click]

The definition of the joint is the same shown for CSE full version, with two differences: it is

possible to add only one node and the search of members and jnodes is always done automatically.


650 COMMANDS: FEM – ASSIGN CONSTRAINT trascrizione/revisione: gennaio 2012

[Cmd_Fem_Assegna_Vincolo.CSE]

To be able to assign a constraint to one or more nodes in the FEM view, we first need to

select them.

To do so, simply click near them when the node selection filter is active. [indica, click nodo

base]

The command to assign a constraint is in the FEM menu. [click] The dialog box that comes

up has three boxes for the translations in the x-, y- and z directions [indica] and three for rotations

about the global axes. [indica]

The degrees of freedom that we tick will be constrained. [spunte]

If we click the Clamped button, all the boxes are ticked. [click]

If we click the Free button, all the boxes are unticked. [click]

We will tick some boxes and click OK to assign the constraints desired to the only node

selected. [spunte, OK, deselezionare nodo]


The dot showing the presence of a constraint contains some white pixels indicating the

degrees of freedom that have been restricted. With the screen resolution used for this video, these

pixels – as shown in the enlargement – may not be visible. [callout]


651 COMMANDS: FEM – ASSIGN END RELEASE

revisione: dicembre 2011

[modello: Cmd_Fem_AssignEndRelease.CSE]

segno di connessione

The command to assign end releases to the beam-type finite elements can be found in the

FEM menu; it is available when the graphical view is active and in FEM mode.

Besides modifying the distribution of forces in the finite element model, end releases also

identify when the members are interrupted and thus help to define hierarchies of members. CSE

uses this information – along with the alignments, the continuity of section and material, etc. –

when automatically searching for members.

The interruption of a member can also be specified with a simple connection code –without

using end releases; in this way, we can define the members correctly without interfering with the

distribution of forces.

If a ready-made FEM model is imported, then any end releases in it are retained.

Connection codes and end releases can also be defined with different colours – for example,

to distinguish between nodes that would otherwise look completely identical.

Connection codes can also be applied to truss elements, which (by definition) already have

end releases at their extremities. By defining connection codes with different colours, we can

distinguish between otherwise-identical truss elements.


There are two ways to assign an end release: manually and automatically. In the manual

method, we specify the parameters for end release, and then we click on all the beam element

extremities that we want to apply it to. In the automatic method, all the extremities needing an end

release are selected; then its parameters are defined; then the end release is applied to all the

selected extremities. An element’s end release is selected if both the element itself and the

corresponding node are selected.

Let’s now assign an end release manually.

We tick the “manual” field. […]

By ticking the “connection” box, we add a connection code without adding end releases.

[…]

We click OK. […]

To assign the connection code, we click on the extremities of the beam elements where a

member is physically interrupted. [esempi] If a member joined at a node has a connection code at

that extremity, then this member will be a slave at that node.

To abort the command, right-click with the mouse or press the ESC key.

Let’s now look at automatic mode: we want to add rotational end releases to the diagonals.

We select the elements and their nodes. [seleziona]


We re-run the command [comando]

We un-tick “manual” […]

We tick the end releases for rotations 2 and 3…[…]

And click OK…[…]

The end releases are then assigned automatically to the selected extremities.


652 COMMANDS: FEM – SEARCH MEMBERS revisione: dicembre 2011

[modello: Cmd_Fem_CercaMembrature.CSE, viste FEM e Jnodi affiancate, senza alfanumerico;

vista Jnodo vuota]

[mostra sezione, materiale e orientazione sintetica per la vista FEM, numerazione membrature per

la vista Jnodi]

segno di connessione

The Search members command runs the automatic search for members in the FEM model.

It can be found in the FEM menu.

There is no need to use this command when the finite element model has been imported

from an external software package, because CSE searches for members automatically. When

creating a model in CSE using the Typical nodes command, we can search for the JNodes

automatically.

If we alter a FEM model, we need to run the Search members command again, because the

information about the members will have been lost.

In the LIGHT version, searching for members is fully automated, hence this command is not

available.

We are now displaying the FEM view of a model in the window on the left, with the JNode

view of the same model on the right; this is currently empty, as the members have not yet been

found.


We run the Search members command [click]: the dedicated view now shows the members

that CSE has automatically found.

Two or more consecutive beam-type finite elements belong to the same member if their axes

are aligned (taking account of any offsets) and if:

the elements have the same cross-section;

the elements are made of the same material;

the elements have the same orientation;

and there are no end releases or connection codes between one element and the other.

For truss-type elements, each element represents a member.

In this model, the beam elements are aligned in pairs, although only the vertical elements on

the right have been recognised as belonging to a single member. Indeed, they are the only ones that

meet all the criteria mentioned a moment ago. [click membratura 1]

If we consider the two vertical elements on the left, we can see that they have the same

section and the same material, and neither of them has an end release or connection code – but their

orientations are different. Hence they are different members. [click membrature 6 e 7]

The two vertical elements in the centre also meet all the criteria bar one: they have different

sections and are therefore two distinct members. [click membrature 3 e 4]

Finally, the two horizontal elements are separated by connection codes and are therefore are

also different members. [click membrature 2 e 5]


660 COMMANDS: JNODES – SEARCH revisione: dicembre 2011

[modello jnodesearch.CSE]

The command to search for JNodes automatically is available from the JNodes menu; it can

be used if the members have already been found. Before JNodes have been searched for, the

dedicated view shows only the members. There is no need to go to the JNode view just to run the

command.

The automatic search for JNodes discards the nodes in the FEM model that have no

connections (such as a node inside a member or a free, unconstrained extremity where there is just a

single member). Then it recognises and catalogues all the other nodes, detecting those that are the

same, which are associated with the same JNode, which is uniquely marked by a code.

Let’s run the JNodes-Search command. [click] First, we are prompted to confirm that we

wish to go ahead. If a search had already been run, then by searching again we would lose any work

done on the JNodes and their associated Renodes. We confirm. [click] The system then asks if the

cuspidal JNodes, which cannot be computed, must be discarded during the search. Cuspidal JNodes

will be discussed later. For now we discard them. [click] Eighteen different JNodes have been

found. [click] CSE asks us to define the preliminary settings for the checks. [click] The settings

can be modified later for individual Renodes. It is advisable to choose at least the standard checks,

to set up the results output listing – as required – and to select how the internal forces are to be

computed. This dialog box is discussed in detail in video 700. [click]

The different JNodes that have been found are shown as boxes with a colour and mark of

their own.


As we can see, some connections are repeated several times in the structure. [click] These

are instances of the same JNode; we only need to apply the work processes once to the associated

Renode. When the checks on the Renode are run, the program will consider all the instances of the

corresponding JNode and check them all for all combinations.

When a JNode is selected, all its corresponding instances are also selected (by definition).

[click] When a single JNode is selected, we can go to the Renode view to construct the connection.

We have seen how the command works; now we will make some important remarks about

JNodes and how they are classified.

A JNode’s topology is defined by the number and the type of members joining at the

connection, by their relative inclinations, sectional properties, materials, orientations, any offsets,

and so on.

Another characteristic that uniquely defines the JNodes is the presence of end releases and

connection codes; these determine the hierarchies between the members of the connection and

classify them as hierarchical, central, cuspidal and tangent nodes.

[passaggio a immagine fissa; add voice narration]

For the purpose of determining the hierarchies, a connection code and an end release

effectively interrupt a member. For simplicity, here we will refer to both of them as “connection

codes”, to emphasise that there is an interruption. A member that is interrupted at the connection

node is a slave. All members consisting of a truss finite element are slaves. Members comprising

one or more beam elements are slaves if they have a connection code at the node.

If a member terminates at the connection node without a connection code, then it is a

cuspidal member.


If the connection node is inside an uninterrupted member, then the member is said to be a

pass-through.

A JNode is hierarchical when it has only one pass-through or cuspidal member – which is

therefore uninterrupted (the master) – while all the others (the slaves) are attached to it. Where there

are only one pass-through member and one or more cuspidal members, the latter are considered

interrupted, and the pass-through member is treated as the master.

In a central JNode, all the members are interrupted and are connected to something that joins

them all together.

In a cuspidal JNode, all the members converge to the node, although more than one of them

is uninterrupted. JNodes of this kind can easily be removed from the model without any loss of

generality, as long as a single cuspidal member remains: we can either interrupt the others (to obtain

a hierarchical JNode) or interrupt all of them (to obtain a central JNode).

A tangent JNode is one where several uninterrupted members pass through the same point.

Using suitable connection codes, we can always achieve a hierarchical or central JNode.


661 COMMANDS: JNODES – EDIT revisione: dicembre 2011

[modello Cmd_Jnodi_Edita.CSE]

The “Edit” command may be found on the JNodes menu. [click] Running this command

brings up a dialog box that can be used to manage and modify the JNodes and to obtain important

information about their topology and the forces affecting them.

The panel lists all the JNodes in the model. The JNodes that are selected in the scene are

ticked; by ticking and unticking them, we can modify the selection status in the scene, which will be

refreshed when we exit from the dialog box.

Along with each JNode’s mark, there is also the connection type (hierarchical, simple,

cuspidal or tangent) and an indication of whether there is a rigid or elastic constraint.

If we click on a line in the box, corresponding to a JNode, it is highlighted in blue. If we tick

a box, the corresponding JNode is selected. Ticks and highlights are independent. Some of the

buttons, which we are about to discuss, work on the highlighted JNode; others, on all the selected

JNodes.

The “Inquire” button brings up a dialog box containing detailed information about the JNode

highlighted in blue. This dialog box will be described shortly.

Using the “No elastic restraint” button removes the elastic constraint from the highlighted

JNode, if CSE has detected that type of constraint there. The elastic constraint is not a nodal

constraint; rather, it means that the FEM model contains elements that act as a restraint.

The “No constraint” button removes any constraint from the highlighted JNode. The FEM

model may contain dummy nodal constraints needed for modelling purposes, such as the rotation


constraint on a node to which only truss-type finite elements are attached. CSE recognises the

JNode as a constraint from the presence of a nodal constraint; this button can be used to remove the

constraint.

The “Sel/unsel” button selects or unselects the JNode highlighted in blue. The “Select all”

and “Unselect all” buttons select and unselect all JNodes.

The selected nodes (the ones that have been ticked) can be removed using the “Delete”

button. A JNode can be deleted if the user does not believe it worth studying in CSE.

Now we will look at the dialog box with the information about the highlighted JNode. This

box appears when we click the “Inquire” button. [evidenziare il jnodo AA - seleziona, interroga]

The dialog always has an “Information about JNode” section, along with additional sections

depending on the JNode type. Here we have the two extra tabs “Master” and “Constraint”, since this

is a hierarchical JNode with a constraint.

The “Info about JNode” tab contains the following data:

the type of JNode and any constraint

the JNode number

the JNode’s mark

the number of occurrences or instances of the JNode in the structure

the number of members making up the connection, and how many of these are cuspidal, pass-

through or interrupted

the number of members comprising a truss-type finite element, and the number of members

comprising one or more beam-type elements

the list of FEM nodes associated with the JNode’s various instances [click]

the number of members corresponding to the node in the box above [click]

the FEM nodes associated with the two extremities of the member in the box alongside [click]

These two nodes thus refer to the current member of the current node. [frecce]

[click su master]


The “Master” section shows the master’s cross-section and the element type (whether it is a

column, a beam, and so on).

The “Slave” panel lists all the slave members in the connection. [click] All the following

data refers to the current slave.

As with the master, the type of element is shown; the type of joint is described (whether it is

a clamp, a torsion or flexural hinge, etc.); and the alignment with the master is defined. [breve

pausa]

Finally, we have the envelope of the internal forces in the current slave for the different

combinations and instances, in the current units, with reference to the finite element with which

each component is associated. If we select a different slave from the list, the envelope is updated in

real time.

We have just seen the section for a hierarchical JNode; for a central JNode, the dialog box is

similar but without the information on the master – as there isn’t one – or on the alignment with it.

[callouts]

[click su attacco]

Finally, if there is a rigid constraint, this dialog box shows the envelope of the constraint

reactions for different JNodes and instances. Alongside each component, the number is shown of

the FEM node in which this force arises.


662 COMMANDS: JNODES – EXTRACT MEMBERS revisione: dicembre 2011

[modello Cmd_Verifiche_Risultati.CSE, vista jnodi, tutto deselezionato]

The “Extract members” command, on the JNodes menu, is available when the JNode view is

active.

This command enables us to “extract” the desired members from the scene, to view a part of

the structure in isolation.

The result depends on which objects have been selected when the command is run: all the

selected members are extracted, as are all those that are joined at a selected JNode. Also included

are the selected JNodes and the JNodes belonging to the extracted members.

[selezione del jnodo AA]

The selected JNode has two instances, so all the members joined at them will be extracted.

[esecuzione del comando]

Once the command has been run, the “Extract” button in the top toolbar remains depressed.


This command is very useful, for example to get a clear idea of the selected JNodes’

position and their importance in the structure.

To return to the normal view, simply run the “Extract” command.

Once the extraction is complete, all the members previously extracted will appear selected.


664 COMMANDS: JNODES – CREATE LISTING, OPEN LISTING revisione: dicembre 2011

[Cmd_Verifiche_Risultati.CSE, vista jnodi]

The JNodes menu offers two commands that enable us to create and open a listing within

CSE that contains important information about all the JNodes in the model.

With the “Create listing” command, CSE writes out a .txt file with the same name as the

model. [click]

The file is output to the same folder where the model is held, and it can be opened directly

from CSE via the “Open listing” command. [click]

This is what the listing looks like.

It begins with a glossary of the terms used. [scorrimento]

The units of measurement for the quantities in the listing are then stated. The units are the

ones that are active in CSE when the listing is generated. [scorrimento]

We now come to the section about the members. This starts with a list of all the members in

the model; for each one, we have the finite element model nodes representing their extremities, the

section and the length. [scorrimento]

For each cross-section, there is the number of entities of different lengths with that section,

with their corresponding weights, along with the overall length and weight for that section.

[scorrimento]

The section on the JNodes starts with a list of all the JNodes in the structure. For each one,

there is the mark, the number of occurrences or instances of the JNode in the structure, the number


of members comprising it, the type (whether it is a hierarchical, central or simple node, and so on)

and whether there is a rigid or elastic constraint. [scorrere]

After the list, each JNode is set out in detail, with various information about its topology and

– if the FEM model has been imported – about the envelope of forces to which it is subject.

If the FEM model has been created directly in CSE, however, the envelope of forces will not

be present.

Let’s look at the information in detail.

The JNode type is shown (hierarchical, central, simple, tangent or cuspidal).

The number of times that the JNode appears in the structure is stated, with the identification

number of the associated FEM nodes.

The number of members comprising the JNode is shown. For every instance of the JNode,

each member involved is listed, with its number. Here, the connection has 3 members; therefore,

each line associated with the instance will contain the identification number for 3 members.

If the JNode is hierarchical, then information is provided about each slave member’s

attachment to the master: the type of finite elements making up the two members; […] their cross-

section […]; whether it is a column, a horizontal beam, a tie-rod, etc. […]; the alignment

classification and constraint type […]; and the angle of inclination between the slave member and

the master […].

If the model has been imported, then the maximum internal forces that the slave transmits to

the master for different checking combinations are also shown.

Finally, if the JNode is a rigid constraint, then the envelope of the constraint reactions for

different checking combinations is also included.


670 COMMANDS: RENODE – SET CURRENT ORIENTATION revisione: dicembre 2011

Besides the global reference system, a component’s local reference system can also be

used as the current reference system. This enables us to have views that are aligned with inclined

elements, to define translations along the axis of an inclined member, to insert components

tangential to other components that are not parallel to the global axes, and so on.

The command can be found in the Renode menu and is also available via a toolbar button.

Once the command has been run [click], if we click on a component’s face, then the current

reference system is immediately changed to that element’s local system. [click]

We can reset the current reference system to the global one by double-clicking. [doppio

click]

The command remains active until the ESCAPE key is pressed or the right mouse button is

clicked; until then, we can continue to amend the current orientation system by clicking on other

components.

If elements had been selected when the command was run, then only these can be clicked to

change the current orientation.

For example, let’s select a diagonal and then run the command again. [click]


The other objects’ faces cannot now be selected.


671 COMMANDS: RENODE – TRIM-EXTEND MEMBER revisione: dicembre 2011

[modello Cmd_Renodo_AllungaAccorcia.CSE in vista renodo]

In Renode view, a member can be extended or trimmed along its axis, from the end where it

is attached to the node. This enables the length of a component to be corrected, so that the

connection can be constructed correctly when there are no axial rigid offsets in the original FEM

model.

This operation can be performed only if no work processes have been applied to the

member; otherwise, when a member has been modified, the concept of extending or trimming may

become ambiguous.

(*) -------------- [custom callout 671_Trim-extend.bmp] ------------

For example, if a rectangular box of material has been removed where a member is attached

to the theoretical node (see figure A), then extending the member would leave us in case B; this is

because the user has defined the rectangular box in a specific spatial position.

To extend the object, leaving the same cut as in the original, we obviously need to define the

box in a position further forward, after we have performed the extension (as in figure C).

The result in case D, on the other hand, can be achieved using a “Face translation”, which

extends only part of the object.

Clearly, work processes defined on the original object may lead to unexpected results when

extensions are applied – because the work processes were devised for a different object. This is why

the “Trim-extend” command is only usable for members that do not have any work processes.


Let’s see how the command works. In this model, the original FEM model has no offsets;

therefore, the column and beam overlap.

We select the horizontal member and run the Trim-extend command from the Renode menu.

One member only must be selected in order for the command to be usable. [click]

The dialog box that appears gives us three ways to define an extension or trim: plane, point

and numeric.

In “plane” mode, the user must click in the scene on a plane at right angles to the member’s

axis; the member’s terminal section at the theoretical extremity will then be extended or trimmed to

leave it lying on the plane to which this face belongs.

“Point” mode works similarly: the user clicks on a point in the scene, and the member’s

terminal face will be translated to lie on a plane parallel to it and passing through the selected point.

In “numeric” mode, the user specifies the magnitude of the translation to apply to the

terminal face along the member’s axis, using another dialog box. The current units of measurement

apply. Positive values mean extensions; negative values represent trims.

Now let’s use “plane” mode: if we want the horizontal member to be just touching the

column’s flange, we select the flange’s outer surface as our plane.

[Click] The member has now been trimmed so that the terminal face lies on the selected

plane, and the two objects no longer overlap.


[vista +y]


672 COMMANDS: RENODE – MODIFY MEMBER revisione: dicembre 2011

[modello qualsiasi]

The “Modify member” command can be used from the Renode menu and as a button in the

Renode toolbar.

The command is available in the Renode graphical view when a single member only has

been selected.

[click]

When the command is run, a dialog box appears for the user to select the optional checks

that are to be performed on the component.

We need to state whether we want the automatic checks on sections with reduced gross area

due to bolt holes, cuts, bevels, etc.

Then we must specify whether we want the automatic FEM model to be created for the

component, if the settings for the checks allow. We can select a non-linear computation by ticking

the relevant box. The non-linear computation settings must be defined in the general settings for the

checks, as described in video 700.

If any material has been removed from the entity (in the form of cuts, bevels, etc.), then the

automatic FEM model will take this into account.


The parameters for automatically creating the model’s mesh need to be set, if a model is

required; the first data item is the mesh size around welds, the edges of objects, and the bearing

surfaces. This first parameter therefore specifies the mesh size in the most critical areas.

The second parameter defines the mesh size in the free areas, away from edges and welds.

This enables us to set the level of homogeneity for the mesh. The first two parameters must be

expressed in the current units.

The third parameter is the minimum angle for the plate-shell finite elements: the default

value is 19.8°, because convergence is assured for angles less than or equal to 20°. If they wish,

users can set larger angles – such as 25 or 30° – and experiment with the convergence in order to

achieve a more sophisticated mesh. In any case, even when a smaller minimum angle is specified,

generally the average angle will be significantly greater, producing a well discretized mesh. In some

cases, the minimum angle is determined by the object’s geometry: for example, the FEM model of a

component that has an angle of 15° at one point cannot have a minimum angle of 20°, because at

least one element – the one in the acute vertex – will necessarily have an angle of 15°.

If we tick the box for the stiffeners, then the FEM model of the current member will

incorporate the FEM models for its stiffeners (if it has any). A stiffener must be connected only to

the current member and to no other component. It must also be marked as a possible stiffener in the

dialog box that is used to add or modify it. For further information, please see the video on adding

cleats/force transferrers.


673A COMMANDS: RENODE – ADD “THROUGH” (CLEAT/FORCE

TRANSFERRER) revisione: dicembre 2011 (rivisto ampiamente)

[renodo qualsiasi, pannello pezzi selezionati]

The “Add through/force transferrer” command is available in the Components sub-menu of

the Renode menu and as a button in the side toolbar. It can be used when the Renode graphical view

is active.

When the command is run, a series of dialog boxes appears for the user to select the type of

force transferrer/cleat. The first one offers the most common objects: plates of various shapes,

simple and paired angles, generically shaped profile stumps, and the constraint block simulating

what the rigid constraints are connected to (a foundation mat, a wall, and so on). The subsequent

dialog boxes contain other types of simple, perforated and bevelled plates, among other

things[click]. Finally, there are finger-plate-type objects [click] and composite plates.

For example, we’re now going to select a simple angle [click]. In the new dialog box, we

define the component’s dimensions, its material and the settings for the checks; the available fields

vary depending on the type of force transferrer. This will all be discussed in the next video.

When we click OK, a new dialog box comes up for us to orient the entity and select where

to insert it. [ok]

To rotate the entity, we can use the arrows, which define rotations about the global or

current reference axes. [click vari] By default, the angles change in increments of 90°, but this can

be altered in the fields at the bottom.

Note: if we are working with a current reference system that differs from the global one,

then the component will be oriented (in the dialog box) according to the current system, and the

rotations will be applied around these axes. This feature is very useful if we want to insert force


transferrers aligned with inclined members, using the reference system of these members as the

current reference system.

The point of insertion in the scene is highlighted; to change it, click Ins. Point and choose

one of the significant points present. [click]

Once we have oriented the entity how we want it, we click OK. [click] Now we need to

click on a point in the scene where the insertion point selected on the component will be inserted.

The force transferrer is then added in. [click]

The force transferrer can be inserted in the exact position required or, if this is more

convenient, it can be placed in the scene and then moved around using the relevant commands.


673B COMMANDS: RENODE – ADD “THROUGH” (CLEAT/FORCE

TRANSFERRER) – PART 2 revisione: dicembre 2011 (rivisto ampiamente)

(accorciato, dividere comunque dalla parte A?)

We are now going to look at the dialog boxes for some of the force transferrers available.

[partire sempre dal primo dialogo]

Rectangular plate [click]. The plate’s three dimensions must be specified: height, width

and thickness. This section is different for other types of component, as we shall see. The

component name can be kept as the default, or a new one can be defined.

The component’s material can be changed by selecting one from the list available in the

model. With the Modify button [click], the details about the current material can be altered; we can

even define a non-linear law for it. [click] We can use the Add button to define a new material,

specifying its parameters in the current units [click]. For information about how to define the non-

linearity, please see the program user guide.

Tick the “simplified checks” box to inlcude this component in the simplified resistance

checks. See the lesson about check settings for more information.

If the settings for the checks require a FEM model to be created for components that need

one, then we must specify whether we want the automatic FEM model to be created for this

component. We can select a non-linear computation by ticking the relevant box. The non-linear

computation settings must be defined in the general settings for the checks, as described in video

700.

If any material has been removed from the entity (in the form of cuts, bevels, etc.), then the

automatic FEM model will take this into account.


The parameters for automatically creating the model’s mesh need to be indicated, if a model

is required; the first data item is the mesh size around welds, edges of objects, and bearing surfaces.

This first parameter specifies the mesh size in the most critical areas.

The second defines the mesh size in the free areas, away from edges and welds. This enables

us to set the level of homogeneity for the mesh. The first two parameters must be expressed in the

current units.

The third parameter is the minimum angle for the plate-shell finite elements: the default

value is 19.8°, because convergence is assured for angles less than or equal to 20°. If they wish,

users can set larger angles – such as 25 or 30° – and experiment with the convergence in order to

achieve a more sophisticated mesh. In any case, even when a smaller minimum angle is specified,

generally the average angle will be significantly greater, producing a well discretized mesh. In some

cases, the minimum angle is determined by the object’s geometry: the FEM model of a triangular

plate that has an angle of 15°, for example, cannot have a minimum angle of 20°, because at least

one element – the one in the most acute vertex – will necessarily have an angle of 15°.

If the distance between two nodes il less than the tolerance specified, then these two nodes

are merged. Default value is 0.5mm.

If we tick the box for the stiffeners search, then the FEM model of the current component

will incorporate the FEM models for its stiffeners (if it has any). A stiffener is connected only to the

current component. It must also be marked as a possible stiffener in the dialog box that is used to

add or modify it.

If, on the other hand, we tick the “It is a stiffener” box in this dialog, then this component

will be used as a possible stiffener for another entity.

We insert the plate. [click OK, rotazione del pezzo, inserimento, cancellazione,

aggiungi tramite]


Dozens of plates are available in various shapes: trapezoidal, circular, regular polygonal,

bevelled rectangular, bevelled triangular, perforated, and more. They all have a dialog box like the

one that we have just seen for rectangular plates, only with different parameters depending on the

type of object. For example, let’s look at a trapezoidal plate [click]. Here, we need to specify the

lower base, upper base, height and thickness. The image is updated in real time as we enter data. A

circular plate will need a radius and thickness; a rectangular polygon, the radius and number of

sides. The appendix to the user guide contains all the dimensions of all the objects available, which

will be especially handy for the more complex shapes.

The rest of the dialog box is the same as for the rectangular plate. [click OK, rotazione del

pezzo, inserimento, cancellazione, selez. colonna, aggiungi tramite]

The bevelled plate is a special case compared to the other components: [click] if, before

running the command, we select a member with a symmetrical H-section, as in this example, then

the parameters for the base, height and bevel size are automatically initialised in the dialog box

according to the dimensions of the selected member. This enables the bevelled plate to fit perfectly

into the member. [inserimento del pezzo, eliminazione, aggiungi tramite]

Hexagonal plate for diagonal. [click] This plate needs three parameters: an angle (in

radians), and a diagonal and a vertical side (in the active units). These three parameters uniquely

define a 6-sided plate according to the criteria shown in the pop-up. The diagonal’s inclination is

determined by the angle; the oblique sides are parallel to the diagonal; the horizontal side is

uniquely determined given the lengths of the vertical side and the diagonal. [custom callout]

[click OK, rotazione del pezzo, inserimento, cancellazione, aggiungi tramite]

We can also add a generic-shaped polygonal plate, by defining a polygon in the form we

want. For a detailed explanation of how to add this component, please see the user guide. [pausa]


Simple angle. [click] First we select the angle from the first drop-down menu. We can filter

the results to show only angles with equal legs or only angles with unequal legs. [click vari]. We

then define the length of the extrudate.

Finally, we need to specify whether the simplified checks must be run for this component

and whether torsion checks must be taken into account.

[inserimento del pezzo, eliminazione, aggiungi tramite]

Double angle bracket [click] The dialog box is similar to the one for the single angle

bracket; we also need to specify the distance between the two angle brackets and, for angles with

unequal legs, whether the paired legs must be the longer or the shorter ones. [inserimento del pezzo,

eliminazione, aggiungi tramite]

Cross-section trunk. [click] The dialog box is like the one for the single angle bracket, with

the difference that any section can be selected here as the extrudate.

By clicking on “Choose cross-section”, we can access CSE’s online archive, containing over

10,000 sections, including rolled, welded, composite and cold-formed sections. The archive can

also be extended using the Samba software, which allows extra cross-sections to be added as

required.

If we tick the type of cross-sections required and click the Archive button, then we reach the

list of sections that meet the filter criteria. Let’s choose a HEB section, for example. [click, scorrere

poi sull’ultimo profilo, OK; inserimento nella scena, aggiungi tramite]

The constraint block. [click] This is used if a Renode has a rigid constraint, to simulate

what the connection is attached to. It is a parallelepiped whose height is greater than or equal to its

width, which in turn is greater than or equal to the thickness. It is used to simulate a foundation mat,

a wall, and so on. [aggiungi]


674 COMMANDS: RENODE – ADD WELD LAYOUT revisione: dicembre 2011

[Cmd_Renodo_Aggiungi_Layout_Saldature.CSE]

The “Add weld layout” command is available from the Components sub-menu of the

Renode menu and as a button in the side toolbar. [callout] It can be used when the Renode

graphical view is active.

After the command is invoked, the layout is inserted in two steps: first, the face to be welded

is selected; then, the welds in the layout are defined.

Let’s run the command and look at the first step. [click] If no objects are selected, then a

face from any object can be chosen; otherwise, the face to be welded must belong to one of the

selected objects. In our case, any face can be chosen, as no components have been selected. After

clicking on the face required, we move on to step two; before defining the welds, though, we need

to introduce some basic concepts.

In order for the weld layout to be applicable, there must be another face touching the face

selected; CSE automatically detects whether such a face exists – if there is one, then we can start

defining the various welds.

[sovrimpressione: callout _674_custom_callout_01, parlare senza cliccare]

The system supports fillet welds and penetration welds. Fillet welds, as now illustrated, are

triangular in section and are applied to the perimeter of the clicked face so that their corner lies on

the edges of the clicked face. Of the two touching faces, the one selected by the user belongs to

component 1, which will take the welds not on the contact plane but on the component’s side faces.

These are the ones running away from the clicked face, shown with a dashed green line in the pop-


up. For any weld, one face is coplanar with the clicked face and connected to component 2, while

another face is connected to the side of component 1.

The two faces connected by the welds do not have to be at right angles [cambio callout

(04)]; the program detects the angle automatically. CSE will alert the user if the angle is greater

than a given threshold value.

Penetration welds, however, are physically within the object. In the scene, the penetration

welds are shown graphically like fillet welds, only thinner (with a 1mm thickness). Besides their

different graphical representation, penetration welds are, of course, computed differently from fillet

welds. Please see the user guide for details.

Returning to the scene, we click the member’s terminal section, which is the one touching

the plate. [click] Because the two surfaces can be welded, the dialog box for defining the welds is

shown.

The image on the right shows the face that was clicked (in green) and the face touching it, as

recognised automatically by CSE (in black). The currently selected edge is highlighted in red. We

can browse the various edges using the arrows [selezionare lato 3]. The “Add” button inserts a

weld on the selected edge [click], which can then be modified, shifted or removed using the

controls provided. The “penetration” box is not ticked, so this is a fillet weld.

The standard approach does not involve adding one weld at a time, but rather the whole

layout at once, according to suitable parameters. We shall look at this shortly. So we shall delete the

selected weld, which is the only one inserted so far, using the “Remove!” button. [click]

To insert several welds at the same time, we use the “Apply to all sides” button. A weld will

be applied to all the sides that are longer than the value set in the field highlighted (expressed in the

current units). If we specify a value greater than zero in the field underneath, then the welds will

stop short of both extremities, by the distance specified; hence they will not be as long as the sides

to which they are attached. All welds will be given the thickness set in the field now highlighted.


Each weld’s throat section depends on the inclination of component 1 and will be computed

automatically by CSE.

We apply the welds [click]; on the sides that are shorter than 50mm (the set value), no welds

have been applied.

The throat section projection for each weld is shown in grey; the current weld is shown in

green, and its parameters are displayed in the section now highlighted [callout].

If we tick the “Penetration” box [click], then the welds are projected inwards. The weld

thicknesses must be kept consistent with the thickness of the plates. Now we’ll return to the fillet

welds. [click]

We can scroll through the various welds using the arrows. The length and thickness of the

selected weld can be modified by typing a new value in the corresponding fields or by using the

arrow buttons provided. If we modify the “Position” field, then the weld is translated along the

edge.

For the weld selected, the following data are also shown: the angle between the active faces

(this is the angle between the face connected to component 1 and that connected to component 2),

and the throat section. As seen earlier, the selected weld can be deleted using the “Remove” button.

CSE automatically computes the position of the layout’s centre of gravity, the direction of

the main axes (which can be seen in the image), the total area and the bending and polar moments

of inertia (shown at the bottom left).

If the “Full constraints in FEM nodes” box is ticked, then the nodes corresponding to this

weld layout will be constrained to the translations and rotations applied in the FEM models of the

components connected to this weld layout. If the box is not ticked, then these nodes will only be

loaded with the forces computed in the various combinations.


Finally, we shall look at manipulating the image. We have the zoom and pan commands

[esempi]; the surfaces can be shaded in [click] and the font size used for the quantities can be

changed using the arrows [aumenta].

The current image can be printed … or copied and pasted into an image editor or calculation

report. [copia e incolla in paint]

If we click OK, then the weld layout is inserted into the scene. [click]


675 COMMANDS: RENODE – ADD BOLT LAYOUT Revisione: gennaio 2012

[Cmd_Renodo_Aggiungi_Bullonatura.CSE]

The “Add bolt layout” command is available in the Components sub-menu of the Renode

menu and as a button in the side toolbar. [callout] It can be used when the graphical view is active

in Renode mode.

The command inserts the layout in two steps: first, the face on which the bolt heads are to lie

selected; then, the layout parameters are defined, including the diameter of the bolts, how they

will be arranged, and the computation settings. When the face has been selected, CSE

automatically searches for all the objects to be drilled, according to the position of the various

components.

Before we run the command, it will help to explain the boltability criteria and how CSE

finds the objects to drill.

[parlare senza muovere il mouse, poi verrà inserito _675_custom_callout_01.bmp]

When the user selects the first face of the first object to be drilled – which we shall call the

first bolting level – the program automatically finds all the subsequent levels, by tracing the

sequence of touching objects involved in the bolt layout. If the objects are arranged in a way that

permits different drilling paths, as illustrated in this example, CSE will discard the objects that do

not have to be drilled based on the layout’s effective position on the selected face. All the bolts in a

given layout must penetrate the same plates. At least 3 bolting levels are needed: in other words,

two touching boltable plates. Up to 10 different plates can be joined, even with non-consecutive

plates belonging to the same object, such as with composite members.


Another criterion that CSE applies is to discard faces that are considered too small to be

bolted. If two or more sides of a four-sided face are smaller than a given user-defined value, then

the face is considered non-boltable; please see video 612 for further details.

[passaggio a _675_custom_callout_02.bpm]

If the bolt layout affects n plates, then there will be n+1 bolting levels. In our case, with 3

drilled plates, we therefore have 4 levels. The bolt layout, and therefore each bolt, has as many

extremities as there are plates; each extremity is located at the midpoint of the thickness of each

plate. Where plates share a plane – and can slip – we have the bolt sections for checking; there are n

minus 1 of them, where n is the number of plates. [pausa]

We return to the scene and run the command [click]. If objects have been selected, then we

can only click on a face belonging to one of them; otherwise, on a face from any object. If we are

interested in a particular object, then it can be convenient to select it, in order to limit the choice of

faces to that object only.

We click on the plate welded to the main beam, which we want to bolt to the secondary

beam. [click] Because the plate is tangential to the web, we have 3 bolting levels, and the layout can

be applied.

Here is the dialog box in which we shall define all the layout’s properties. As this dialog box

is complex, it needs to be dealt with in some detail: see lesson 676 for a full description. For now,

we shall just enter the layout data quickly.

We are going to use M12 bolts of class 8.8 [assegnazione]


The layout will be arranged regularly, in one column by three lines, with a separation

distance between the bolts of 36mm (these being the active units). [righe: 3]

To position the bolt layout correctly, we shall give it an offset of 30mm in the x direction.

[Dx=30]

We want the bolts to work on a shear-only basis, because this is a hinged connection.

When we click OK, the layout is inserted into the scene. [click, rotazioni varie] The nuts

and bolt heads can be seen.

The next lesson gives a detailed description of the dialog box used to define the layout.


676 COMMANDS: RENODE – ADD BOLT LAYOUT (DIALOG BOX) Revisione: gennaio 2012

[Cmd_Renodo_Aggiungi_Bullonatura_Dialogo..CSE; dialogo già aperto]

[PARTE 1]

In this lesson, we look closely at the dialog box used to define a bolt layout. As we saw in

the previous lesson, this dialog box appears after we have selected the face that the bolt heads are

going to lie on. CSE has already found all the possible bolting levels and the objects that can be

drilled.

The image on the right shows all the boltable faces at the various bolting levels: the

currently selected face is shown in green, and the face clicked in the scene is shown in red – except

when it is the selected one, as in this case.

The layout currently has just one bolt; we can see its distances from the edges of the selected

face. When there are more bolts, the separations are shown too. If we select the other faces using

the arrows, the figure is updated in real time. [click vari]

We can zoom on the image and shift it, using the commands provided. [zoom, pan]

The dimensions can be increased or decreased, by clicking and holding the relevant arrows.

The “Fill” button is used to shade-in the various faces [2 click]; the “Hexagons” button

shows the bolts’ overall sizes [2 click]. The current image can be printed … or copied and pasted

into an image editor or calculation report.


As we have already seen how the image can be manipulated, we shall now move on to

setting up the layout parameters.

The “Change” button [click] brings up another dialog box where the user can select the

diameter and class for the bolts in the layout using the drop-down menus; we can also specify

whether the shear computation must consider the threaded area or the gross area, and whether the

play between bolt and hole must be normal or high precision. All the bolts in the same layout have

the same properties and the same computation settings.

The arrangement of the bolts can be defined in 4 different ways: an arrangement in regular

rows and columns, based on the parameter settings in the panel below [4x4, interassi 100 ]; in this

arrangement, if we tick the “Empty inside” box [click] then only the bolts on the border are left);

[pausa *] a staggered arrangement, where the odd columns have a bolt fewer; [pausa *] a circular

arrangement, where the “Rows” field defines the number of concentric rings and the “Columns”

field determines the number of bolts on each ring. In the circular arrangement, one separation

specifies the distance (in the current units) between the bolts in the innermost ring; together with the

number of bolts, this uniquely determines its radius. The other separation represents the increase in

radius for the successive rings.

[*] pausa nella registrazione, modificare il numero di righe e colonne e

gli interassi, ricominciare a registrare; in produzione inserire un fade in

Sfalsata: righe: 5 colonne: 4 Interassi: 70 50

Circolare: righe: 2 colonne: 9 Interassi: 45 100

Finally, there is the free arrangement, in which the bolts can be added, removed and moved

around at will using the controls provided, which become active. We shall look at this arrangement

shortly.


We can give the layout an offset in the x and y directions (expressed in the current units) and

rotate the layout by specifying an angle (in degrees) other than zero. [esempi] This button [indica]

is used to define a rotation angle that automatically aligns the layout to the circular plates.

[fade - tornare a disposizione regolare, 4x4, interassi 100, zoomare]

We shall now look at the free arrangement. First of all, when we start to work with the free

arrangement, the last defined arrangement is offered as the default; therefore, it can help to start

from a standard configuration and then amend it to suit our requirements.

- Clicking the “Add” button [click] inserts a bolt at the centre of the layout and selects it (in

yellow).

- The “Remove” button deletes all the selected bolts. [rimuovi]

- The “Sel/Unsel” button is used to select or unselect the current bolt; this is the one with the

red border. [due click]

- The arrows underneath can be used to change which is the current bolt.[click…]

- “All” selects all the bolts; “None” unselects them all. [click tutti, nessuno]

- The X and Y arrows are used to shift all the selected bolts upwards, downwards, left or

right. [selezionare un bullone e traslarlo]

The distances between the bolts and their distances from the edges are updated in real time

as bolts are added, removed and shifted.

In the free arrangement, we can define offsets for the whole layout but not rotate it.

[highlight callout su questi controlli]


---------------------------------------------------------------------------------------------------------------

[PARTE 2]

The “Basic information” panel contains the following data, calculated automatically by

CSE: the net length of the bolt layout, which is the sum of the thicknesses of all the drilled plates,

in the active units of measurement; the minimum thickness of all the drilled plates, in the active

units; and the multiplicity, which is the number of sections to be checked for the bolts.

Let’s look at the various ways in which the bolt layout can operate.

Shear-only bolts: if ticked, the bolts work on a shear-only (not tension) basis. For example,

in the computation for a splice joint between two H-section beam stumps, if we want to ensure that

the shear parallel to the web is not assigned to the bolts on the flanges, and vice-versa, then this is

the option to use.

In general, a bolt layout’s stiffness is directly proportional to the number of bolts in it, and to

the fourth power of the bolt radius, and inversely proportional to the layout’s net length. CSE has a

parameter called the “flexibility index”: the translational stiffness of a bolt layout is also inversely

proportional to the cube of the flexibility index set by the user. If the flexibility index is greater than

one, then there will be a loss of stiffness.

Compressed bolts: if this box is ticked, then the bolts will also be checked when subjected

to compression. Otherwise, their compression is calculated but is not taken into account in the

checks. This option also affects the way a bolt layout with bearing support is calculated (if the

compressed bolts assist the bearing support or not).

Slip-resistant joint: with this option, the bolt layout is also slip resistant; values must be

supplied in the associated dialog box [click] for the coefficient of friction Mu, the hole coefficient

Fi and the preload for the bolts, expressed as the fraction Kn of the ultimate bolt load. Further

information is available in the online program guide, which can be accessed by pressing F1.

[premere, uscire dalla guida, uscire dal dialogo] If a preload is defined in the sub-dialog, but the


box is not ticked, then the bolts will not be slip resistant; instead, the preload will be considered

during the check as an additional internal force in the bolts.

The Is an anchor option needs to be ticked when the bolt layout is an anchor. In this dialog

box [click] , we can set the anchor type, the equivalent length and the tangential bond stress. [esci]

A bearing surface can be used if we want the support to react to compression. After ticking

this option, we define the constitutive law for the support material, using a dedicated dialog box

[click]. Four formulations are available; all are no-tension types – one linear and three non-linear.

The unlimited elastic no-tension constitutive law: we need to define a homogenization

factor m (which reduces the elastic modulus of the bolts) and the maximum compressive stress

sigma,max. For example, if the bearing support material is a type of concrete, then the

homogenization coefficient can be set at 1/15. Homogenization is relative to steel.

The elastic-perfectly plastic no-tension constitutive law: here, the elastic modulus E, the

yield stress sy and the ultimate deformation eu must all be defined, along with the safety factor M.

The parabola-rectangle no-tension constitutive law: the vertex of the parabola with stress

s1 and deformation e1 must be defined, along with the ultimate deformation eu and the safety factor

M. [gamma M]

The trilinear no-tension constitutive law: the stress-deformation points with coordinates (s3,

e3), (s2, e2) and (su, eu) must be defined, along with the safety factor M.

Except for the dimensional numbers m and M, the values must be specified in the active

units of measurement.


We shall now define a parabola-rectangle no-tension constitutive law. [click, click] We

define s1, e1 and eu. [highlight, digita valori]. We set gamma M to 1.5 […]. We click OK to return

to the main dialog box. [OK]

Using a dedicated dialog box, we define the bearing surface – this is the area where the

object acting as the bearing support may be under compression. [click] This surface can be defined

in CSE in accordance with the standard, by adding a suitable projection around the outlines of the

members and their stiffeners. Two or more separate bearing surfaces can be defined, if need be.

First, we specify that the object currently selected in the image must be subject to the

crushing check – which we shall discuss shortly. This object is the concrete constraint block, shown

in green. [click] Next, we select the face of the plate [click frecce] and set its entire surface as the

bearing surface. [click primo =] Part 3 of this video will show how to define a bearing surface in

more detail. Note that the edge of the constraint block, if not selected, is now shown in yellow,

because this is the object that will be checked for crushing. We click OK to return to the main

dialog box. [ok]

We mentioned the crushing check. The ratio between the maximum compressive stress

acting on the bearing support, as calculated by the program, and the maximum compressive stress

possible under the specified constitutive law represents the support’s coefficient of utilisation. This

utilisation helps to determine the utilisation of the component that constitutes the bearing support.

When a bolt layout has a bearing support, we can choose whether the computation should

use the bolts’ net area or their gross area – and also, whether it should take into account the bolts’

own moment of inertia.

CSE calculates the maximum centred axial force, the maximum centred shear and the

maximum torque that the bolt layout can withstand. These values are shown in the “Limit values of

elementary actions” panel. The user can choose whether to use the elastic or plastic limits.


During the process of defining the bolt arrangement, CSE warns if not all the bolts connect

the same objects or if some bolts are outside the faces; if we want to suppress these error messages,

we can tick this box.

Part three of this video will discuss how to define complex bearing surfaces and how to use

the block-tearing check dialog box.

A note about how bolts are displayed based on the computation settings:

[_676_custom_callout_01.bmp]: if the bolts work on both a tension and a shear basis, then they are

displayed with a dot on their head; if preloaded, then a triangle is shown on their head; and if the

joint is slip resistant, then diagonals are displayed on the side faces of the head. These display

conventions are not applied in the post-processing stage. Anchors are represented differently from

normal bolts, in that they have no screws.

---------------------------------------------------------------------------------------------------------------

[PARTE 3]

[Dlg_Contrast.CSE (bullonatura 2x2 M22-8.8 interassi 220/350, spunte solo su ancoraggio e poligonale

contrasto, dati contrasto parabola rettangolo: –21.25, -0.002, -0.0035, 1.5]

In this third part of the video, we shall look at two sub-dialog boxes available from the main

dialog box for adding bolt layouts. The first is used to define one or more bearing surfaces in more

detail than simply by selecting a face; the second allows the various block-tearing failure paths to be

examined on the faces of the drilled objects, based on the angle of incidence of the resultant.

[apri dialogo modifica bullonatura]

Firstly, we shall look at the dialog box used to define bearing support polygons. This is

accessed using the Bearing button below the image. [click]


The main controls in this dialog box are those used to define the bearing surface (or

surfaces) and to select which object will be checked for crushing. [2 highlight callouts]

To select the object for checking, click the highlighted button when one of this object’s

faces is the current face (shown in green). In our example, the crushed component will be the

concrete constraint block, one of whose faces is already green. [click] The face of the object to be

checked is shown in yellow; we cannot see this yet, because it is also the current face.

We now specify the bearing surface. Using the arrows under the image, we browse the

various faces and select the one corresponding to the outline of the base plate. [faccia 3] If we click

the button now highlighted, this face is set as the bearing support polygon, and the entire area under

the base plate may be subject to crushing. [click]

Working with the entire surface of the base plate may not be good for safety. This is because

the base plate is deformable and can transfer the compression stresses from the column to the

concrete block only in a limited zone around the column’s web and flanges and around the

stiffeners. In this case, as we shall see, the different is almost negligible, but for safety’s sake, we

need to specify the polygon in accordance with the standard. We select the member [ultima faccia].

If we clicked on the button that we saw before, the member would become the bearing support

polygon [click]; if we click the button below it, the member is given a projecting border c defined

in the box shown. [click] The parameter c determines the strip in which the stress can be transmitted

from each plate to the concrete block via the base plate. Its value can be entered manually or

computed automatically based on the following parameters: the base plate’s thickness and yield

stress, and the design stress of the material acting as the support. We input the parameters for the

model in question [30, 355]. The third parameter is calculated automatically by CSE based on the

data for the material input in the Bearing data dialog box, as seen in part two of this video.

Now we tell the system to compute c; [click] it is evaluated using this formula. [callout] We

then set the current face, with a projecting border c, as the bearing support polygon. [click]

As we can see, it extends beyond the edges of the base plate; we shall deal with this in a

moment. We now add the contributions to the polygon from the two stiffeners, each also with a

projecting border c. [faccia 6, click U] This button has created a bearing surface that comprises the

union of the previous one and the bordered outline of the current face. We can perform the same

operation for the other stiffener [faccia 5, click] ; finally, we remove the parts of the bearing surface

that project beyond the base plate: we select the appropriate face and intersect it with the polygon.

[faccia 4, Int]


The Sub button, which we haven’t needed to use here, allows us to subtract the current face

from the currently defined bearing surface.

As mentioned earlier, the reduction in the base plate’s overall surface is not significant in

this case. The current polygon is safety-friendly and will facilitate a more precise distribution of the

pressures in any automatic FEM model of the base plate. In any case, we can select the base plate

and use its entire surface as a bearing support. [click]

The Bearing data panel shows two statistics computed by CSE: the total area of the bearing

surface and the crushed object’s resistance to simple compression, based on the specified stress.

[salvare filmato]

[fade su Dlg_BlockTear.CSE]

We shall now look at the dialog box for block tearing, using another model. To make things

clearer, we shall illustrate a simple model comprising two plates connected by a bolt layout.

[apri dialogo modifica bullonatura]

Using the “Block tear” button [callout], we bring up the dialog box containing the

information that CSE has computed for this failure mode. [click, zoom dell’immagine, non mostrare

quote]

The basic information about the bolt layout, taken from the main dialog box, is shown at the

top left. The data underneath refer to the current face (the one selected in green in the image). We

select the face we want, using the buttons under the figure. [selezione della faccia 3 o 4]

The figure shows the most critical block-tearing failure path among all those examined by

CSE, based on the direction of the resultant. [callout] The convention as to the force’s angle of

incidence is shown in this diagram. [custom callout]

The field above shows the surfaces’ total ultimate strength along the most critical failure

path. .This strength is called Fultima [callout].

If we alter the force’s angle of incidence, the failure path and its strength are updated in real

time. [arrivare fino a 75°]


When we click the “Worst condition?” button, the angle is automatically set to the force

inclination that corresponds to the path with the lowest strength across all inclinations. This strength

and the associated failure path are shown together.

Finally, if we click the “Diagram” button, [click] the plot of the strength for different force

incidence angles is shown in the image.

For a given direction, this dialog box shows the path with the least strength; however, the

checks may well not determine that path to be the most critical for a force acting in that direction.

This is because the various paths may not affect all the bolts, but only a subset of them. The

strength of a path must be compared with the forces transmitted only by the bolts on that path.

Hence, the path of least strength may only involve some of the bolts in the layout; therefore its

applied force to strength ratio may be less than that for some other path that, despite having greater

strength, is also subject to a greater overall resultant, because it has more bolts.

[custom callout*]

PjU

Pj

PU

P

F

F

F

F

,min,

min


680 COMMANDS: RENODE –DELETE COMPONENTS revisione: dicembre 2011

The Delete command in the Renode menu deletes the selected components; it is available

when the graphical view is active in Renode mode.

There is another way to delete components, using the alphanumeric view in the Renode

panel: after clicking on the name of a component in the list, we can delete it by pressing the Del key

on the keyboard.

When a component is deleted, all the additional conditions and variables are also deleted.

This is because they could reference predefined variables belonging to the deleted component or

additional variables that refer to the component’s predefined variables in turn.

This is why it is good practice to add variables and conditions after the Renode has been

constructed.


681 COMMANDS: RENODE – MODIFY COMPONENT revisione: dicembre 2011

The Modify command in the Renode menu is available when the graphical view is active in

Renode mode; it brings up the dialog box used to modify the selected component. One component

only must be selected.

The dialog box for modifying each type of component is the same as that used to insert it;

for details about these dialog boxes, please therefore see the lessons about adding the various

entities.

The dialog box initially shows the current parameters for the component being modified;

after the changes are made, the component will reflect the new parameters.

There is another way to modify components, using the Renode panel in the alphanumeric

view: if we double-click on the name of a component in the list (or press the spacebar), then the

Modify dialog box appears, regardless of the current selection status.

Note that the Modify component command is not available when recording a parametric Renode.


682 COMMANDS: RENODE – COPY-RECOPY COMPONENTS revisione: dicembre 2011

[Cmd_Renodo_Sposta_Copia.CSE; renodo AD, piastra selezionata]

The Copy command is available in Renode view when at least one component has been

selected (members excluded). It is available from the Renode menu and by clicking the button

shown.

The command enables us to create copies of the selected force transferrers/cleats and joiners,

by defining a shift vector relative to the original components. The command does not affect the

members that are selected, if any.

When the command is run, a dialog box appears that allows us to define the shift vector for

the selected objects in various ways. [click; inserire filmato già fatto per il comando sposta]

----------parte di filmato valida anche per filmato 685 – Sposta---------

There are 5 ways to define a translation vector and 3 ways to define a rotation vector.

Let’s look at translations first. If we choose the “2 points” method, we then have to click on

two points in the scene to define a vector in space. More specifically, the first point is the vector’s

tail; the second, its head.


In the “2 faces” method, two parallel faces in the scene must be clicked: the vector will be

normal to them, with its tail lying in the plane of the first face and its head in the plane of the

second.

In the “face + incr.” method, we click on a face and then specify the vector’s modulus (in

the current units): if the value is positive, then the vector will have the same direction as the normal

emerging from the face.

The “face point” method involves clicking first on a face, then on a point; the vector will be

the normal emerging from the face, with modulus equal to the distance between the face and the

plane parallel to it that contains the selected point.

In the “numeric” method, the translation vector’s three components must be defined (in the

current units).

For rotations, the first method requires that we click two points in the scene to define the

axis of rotation; we then specify the angle, in degrees.

In the second method, a member must be selected by clicking on any of its faces: the axis of

rotation is this member’s axis; we then specify the angle, in degrees.

Finally, in the numeric method, the axis of rotation is defined using the coordinates of two

points.

-----------------------------------------------------------------------------------

[Cmd_Renodo_Sposta_Copia.CSE; renodo AD, piastra selezionata]

In this example, we shall see how to create new stiffeners quickly, with the associated

welds, starting from the currently selected components.

First, we run the Copy command, selecting the numeric translation method. [click]


We define a vector of 185mm in the –z direction. [z=-185]

A copy has now been created of the stiffener and its welds. We shall now use the Recopy command

to put another welded stiffener a further 185 millimetres down the column. [ricopia]

We now select the stiffeners and the unselected welds using a rectangular box ... [click…]

… and copy them to the other side of the column using the Copy command in member+angle mode.

[click]

Three stiffeners have now been added with their respective welds.


683 COMMANDS: RENODE – ROTATE COMPONENTS revisione: dicembre 2011

[renodo AC Cmd_Fem_Assegna_Svincolo.CSE, 3-4 scatti ruota giù]

The “Rotate” command can be used when the graphical view is active and at least one

component (members excluded) has been selected. The command is available in the Components

sub-menu of the Renode menu and as a button in the side toolbar.

When the command is run, a dialog box appears for the user to define the rotation for the

currently selected objects. [click]

If the “Local” button is not selected, then the rotations are defined in the global or current

reference system; otherwise, each of the selected objects will be rotated according to the orientation

of the axes in its local system.

The DR fields must be set to the magnitude of the rotation about the respective axes, in

degrees; the arrow buttons can be used to apply the relevant increments. For example, we can

specify a rotation of 45° about the y-axis in the global reference system. [DRy=45, freccia ]

The component is rotated in the scene in real time.


684 COMMANDS: RENODE – MODIFY BOLT LAYOUT SETTINGS revisione: dicembre 2011

[renodo Cmd_Modifica_Opzioni_Bullonature.CSE, pannello pezzi selezionati, vista grafica attiva

con bulloni flange selezionati]

The Modify bolt layout settings command can be found in the Components sub-menu of the

Renode menu. It can be used when the graphical view is active and when at least one bolt layout is

selected. [click]

This command enables users to change the operational settings for the selected bolt layouts

at the same time, as follows: shear-only or shear-and-tension bolts; shear-and-compression bolts;

no-slip joints; anchor bolts.

For example, we want the bolt layouts on the currently selected flanges to work not under

shear and tension, as at present[highlight callout], but rather on a shear-only basis. So we tick the

“shear only” option and activate the change. When we click OK, all the selected bolt layouts will

work on a shear-only basis; the other bolt layouts will not be affected and will continue to work as

before. [click, highlight rectangle]


685 COMMANDS: RENODE – SHIFT COMPONENTS revisione: dicembre 2011

[Cmd_Renodo_Sposta_Copia.CSE; nodo AD, piastra selezionata]

The Shift command can be used in Renode view when at least one component has been

selected. It is available from the Renode menu and by clicking the button shown.

The command allows users to move all types of component around in the scene: force

transferrers/cleats, members and joiners. Strictly speaking, there should be no need to shift

members, because appropriate offsets can be set in the FEM model. Nonetheless, members can be

shifted; we need to remember that this will entail adding moments of transport in proportion to the

magnitude of the shift, for consistency with the FEM model. So if it is absolutely necessary, for

construction purposes, to shift the members, then we must take care to use only small shifts, bearing

in mind that we can define suitable offsets in the FEM model instead.

When the command is run, a dialog box appears that allows us to define the shift vector for

the selected objects in various ways.

----------parte di filmato valida anche per filmato 682 – Copia---------

There are 5 ways to define a translation vector and 3 ways to define a rotation vector.

Let’s look at translations first: if we choose the “2 points” method, we then

have to click two points in the scene to define a vector in space. More specifically, the first point is

the vector’s tail; the second, its head.


In the “2 faces” method, two parallel faces in the scene must be clicked: the vector will be

normal to them, with its tail lying in the plane of the first face and its head in the plane of the

second.

In the “face + incr.” method, we click on a face and then specify the vector’s modulus (in

the current units): if the value is positive, then the vector will have the same direction as the normal

emerging from the face.

The “Face point” method involves clicking first on a face, then on a point; the vector will be

the normal emerging from the face, with modulus equal to the distance between the face and the

plane parallel to it that contains the selected point.

In the “numeric” method, the translation vector’s three components must be defined (in the

current units).

For rotations, the first method requires that we click two points in the scene to define the

axis of rotation; we then specify the angle, in degrees.

In the second method, a member must be selected by clicking on any of its faces: the axis of

rotation is this member’s axis; we then specify the angle, in degrees.

Finally, in the numeric method, the axis of rotation is defined using the coordinates of two

points.

-----------------------------------------------------------------------------------

Now let’s look at the “2 faces” translation method [click] suppose we want the selected

plate to touch the column’s flange: so we click the plate’s vertical face, then the external face of the

vertical member’s flange.


686 COMMANDS: RENODE – WORK PROCESSES revisione: gennaio 2012

[Cmd_Renodo_Lavorazioni.CSE, una lavorazione presente]

The “Work processes” command is available in the Renode menu and as a button in the side

toolbar. It can be used when the graphical view is active in Renode mode, and when exactly one

component is selected, ignoring joiners.

Selecting the command brings up a dialog box where users can select a work process to

apply to the selected entity or remove work processes previously applied to it.

The available work processes are: removals of polygonal and rectangular box prisms; face

rotations; circular, triangular and square bevels; and face translations. [callouts]

After selecting the work process and inserting an optional description, we click on “Add”

and return to the graphical view to define the work process.

Some work processes require additional parameters. The value set in the “Bevel radius” box

determines the size not only of circular, triangular and square bevels but also of any circular bevels

in prism removals.

The “Command options” panel contains parameters controlling how the significant points

are displayed on the selected object, to enable prism removals to be applied.

Indeed, during these operations, points in the scene are used to determine the form of the

rectangular box or polygon. All the vertices of all the components in the scene can be clicked, and

the points spaced at one-half, one-third and one-quarter intervals along all sides belonging to the


object in question can be shown. We can also display on these sides a set of equidistant points at the

interval specified in the “Delta S” field (this value is expressed in the current units).

The left hand panel lists all the work processes already applied to the selected component.

They can be removed in reverse order to that in which they were defined (latest first); this is

because each work process was applied to an entity that had already been modified by all the

previous work processes. If we select the last one in the list and click on the button underneath, then

the work process is removed. [click]

Let’s now look at the various work processes in detail. Because prism removals require a

more detailed explanation, we shall leave them until last.

Face rotation. No parameters need to be specified in the dialog box. We simply click “Add”

to insert the work process. [click] We need to click on the face that we want to rotate in the scene;

this is the reference face, to which the first face will become parallel. The reference face may

belong to another component. [click sezione non lavorata, click faccia inclinata]

Bevels. The various types of bevel are added in the same way: after clicking “Add”, we need

to click in the scene on the two vertices of the corner that we wish to bevel. The bevel size is

specified in the field provided. [callout]

[custom callout 1] Bevelling can involve either removing or adding material, according to

the position of the edges that meet at the corner, as shown in the pop-up. [silenzio di alcuni

secondi]

As a demonstration, we shall add a circular bevel. [click] We click on the two vertices of the

corner that we want to bevel. In this case, material will be removed [click]. To avoid burdening the

view with graphical details that are unimportant when computing the connection, CSE

approximates circular bevels with two planar faces. Bevels are shown correctly, however, in the

working drawings.


[rieseguire il comando lavorazioni]

Triangular and square bevels work as for circular ones; only the form of the bevel is

different.

Face translations need no further parameters in the dialog box. By clicking “Add”, we

return to the scene: here we need to click on the face to translate. In order for the work process to be

applied, the selected face must have parallel edges [click]. After the face has been selected, a dialog

box appears for us to enter the magnitude of the translation, in the current units. Positive values

mean that the face is translated outwards. [+50mm, click]

This work process is particularly suited to extending or trimming members to which other

work processes have already been applied (see video 671 for details).

We’ll now look at prism removals. As mentioned earlier, the parameters we need are in the

“Command options” panel, together with the bevel radius (when defining bevels). [callouts]

[Vista +y, rieseguire il comando lavorazioni]

We’ll apply a rectangular box prism removal. [click]. We need to click on the two

opposing vertices defining a rectangle in the scene, with one or more bevelled corners, if required.

The shape defined will be extruded to infinity in the direction normal to the screen; the part of the

component being worked on that lies within the generated prism will be removed.

The significant points are as previously defined. We click on the first point [click]. A dialog

box appears for us to specify the corners that we want to bevel [smusso]. We click “OK” and then

select the second point in the scene. [click, vista isometrica]


The material contained inside the prism that we defined has been removed.

[Vista +y, rieseguire il comando lavorazioni]

Finally, let’s see the removal of a polygonal prism. The process is similar to that for a

rectangular box prism, although here the base of the extruded prism is a generic polygon. [click]

The polygon must be defined by clicking on a series of points in the scene, then closing the

line back to the first point. The section thus defined will be extruded and the material inside the

prism removed. [alcuni click senza richiudere la poligonale]

The sides of the polygon can be defined not only by clicking on points in the scene but also

numerically: if we press the space bar, a dialog box appears offering three different ways to input

the information.

Dx – Dy [click] requires the new point’s x- and y-coordinates relative to the last one

entered, in the current units. The reference system is in the same plane as the screen, with axes

oriented as in the pop-up. [custom callout 2]

[ESC, barra spaziatrice]

The second way [click] involves entering an angle (in degrees), using the convention shown

in the pop-up, and the length of the side, in the current units.



The third way [click] is like the second, only the angle specified is an increment (if the value

is positive) relative to the inclination of the last side entered.


As an additional option, the last side entered can be removed [callout] and, by ticking the

box at the bottom, we can add a curvilinear connecting edge between the last side entered and the

next.

[ESC, chiudere la poligonale, vista isometrica]


689 COMMANDS: RENODE – ADD VARIABLE revisione: dicembre 2011

The “Add variable” command is available from the Renode menu and by clicking the button

shown [callout].

It can be used when the Renode alphanumeric view is active.

In the dialog box, we need to specify: a name for the variable […]; the formula defining it

[…]; its dimension (whether it is a force, length, surface, absolute number, etc.) […]; and an

optional description for it[…].

The panel at the bottom left lists all the Renode’s components, along with their geometrical

properties. [click vari…]

To specify the formula, we can use variables already present in the model (predefined or

added earlier) and the alphanumeric keypad provided. The keypad buttons are described in the user

guide and online help, which can be called up by pressing the F1 key [tasto F1 tastierino

chiudi; click su “max”]; to use an existing variable, simply click on it [m2.T2…. virgola….

M2.T3, chiusa parentesi]. The formula that we have just defined means “the maximum of the shear

in the direction of axis 2 and that in the direction of axis 3, on member m2”; this is therefore a

force. [dimensionalità, nome “var_utente_1”].

We complete the variable by adding a description for it. [digitare “massimo taglio su m2”]

When we click OK, the variable is inserted. It is included in the list of additional variables,

with its numerical value, and it can be used to define new variables or additional checking

conditions. [click per mostrare la variabile]


In this case, the value zero is returned, because the internal forces in the members are

variables that are instantiated during the checks; they have different values in different

combinations and instances.

If the user checks are selected in the settings for the checks, then the output listing includes

all the variables added by the user. We check the Renode [verifica!, mostra]. In the listing, the

additional variables are shown before the automatic checks.

[aggiungere in coda il tastierino]


690 COMMANDS: RENODE – ADD CONDITION revisione: dicembre 2011

[Interfaccia.CSE] The “Add condition” command is available on the Renode menu and via

the button shown. [callout]

It can be used when the Renode alphanumeric view is active.

In the dialog box, the user must specify the inequality that defines the condition […];

descriptions can be added, if desired, for the condition and for the two members involved. […]

We also need to specify whether the condition is a prerequisite for the Renode to be

applicable or a genuine additional check. […]

Finally, if it is an additional check, we need to specify which component the check applies

to. This component will be associated with the coefficients of utilisation computed. […]

The panel at the bottom left lists all the Renode’s components, along with their geometrical

properties. [click vari…]

To specify the formula, we can use variables already present in the model (predefined or

added earlier) and the alphanumeric keypad provided. The keypad buttons are described in the user

guide and online help, which can be called up by pressing the F1 key [tasto F1 tastierino

chiudi; click su “min”]; to use an existing variable, simply click on it. For example, we can define

a checking condition on component m2, to verify that the axial force on this member never exceeds

the maximum load that the web can withstand on its own: m2.N … must be less than or equal … to


the yield stress multiplied by the area of the web of member m2 [m2.fy * m2.Aw]. The condition

is a check … and we associate it with component m2 …

We add the various descriptions.

[verifica aggiuntiva m2 azione assiale resistenza della sola anima]

When we click OK, the condition is inserted. [OK, click per mostrare la variabile] It has

now been included in the list of additional conditions.

A prerequisite has also been added previously into this model. [click]

For the connection to be applicable, the width of member m4 needs to be less than the net

height of member m1’s web. As this is a prerequisite, it must not be associated with any

component.

[Apertura del tabulato nella posizione corretta]

If the settings for the checks require that the user checks are run too, then all the conditions

added by the user are printed in the listing before the section on the automatic checks.

The check on any prerequisites, which CSE performs before all the other checks, is included

at the start of the section dedicated to the automatic checks. If a requirement has been satisfied, it

will have a coefficient of less than 1.

The additional checking conditions, on the other hand, are treated like all the other checks.

Their results are output only when they represent the maximum coefficient of utilisation for all the

checks specified for that particular entity.


[scorrere…]

In this case, the check that we added for member m2 is never the most critical condition.

[aggiungere descrizione tastierino numerico]


691 COMMANDS: RENODE – MODIFY VARIABLE OR CONDITION revisione: dicembre 2011

[un modello qualsiasi in vista renodo, con almeno una variabile e una condizione]

The “Modify variable or condition” command is on the “Variables and conditions” sub-

menu of the Renode menu and is available when the alphanumeric view is active in Variables and

conditions mode. Running the command brings up the dialog for editing the variable or additional

condition selected.

The same dialog box is used for both modifying and inserting; for details about it, please see

the lessons about inserting.

The dialog box initially shows the current parameters for the variable or condition being

modified. The name cannot be changed, because the Renode may have other variables or conditions

that refer to the existing name.

There is another way to access the dialog box, namely by double-clicking on the name of a

variable or condition in the list.


692 COMMANDS: RENODE – DELETE VARIABLE OR CONDITION revisione: dicembre 2011

[un modello qualsiasi in vista renodo, con almeno una variabile e una condizione]

The “Delete variable or condition” command is on the “Variables and conditions” sub-menu

of the Renode menu and is available when the alphanumeric view is active in Variables and

conditions mode. It deletes the selected variable or condition.

There is another way to delete variables and conditions: after clicking on a variable or

condition in the list, we can delete it by pressing the Del key on the keyboard.

Please note that if a variable has been used by other variables or conditions, then the only way to

delete it is to find the variables or conditions that depend on it and delete them first.


695 COMMANDS: RENODE – CHECK OVERLAPS revisione: dicembre 2011

[modello Cmd_Renodo_AllungaAccorcia.CSE in vista renodo

The “Check overlaps” command, in the Renode menu, finds any overlaps between the

objects in the scene. This is particularly useful, because users can inadvertently introduce overlaps

in various ways – such as by incorrectly positioning a component, or by failing to define offsets in

the original FEM model.

If sounds are enabled, the user will notice an overlap immediately; in any case, this

command is an important tool for detecting overlapping objects in the scene itself.

[click] After the command is run, a message is shown informing us whether overlapping

objects have been found. If they have, then all the objects affected are selected, and the others are

unselected; if there are no overlaps, then all the objects are unselected.


696 COMMANDS: RENODE – CHECK COHERENCE revisione: dicembre 2011

[modello Cmd_Renodo_Controlla_Coerenza.CSE, vista renodo, 2-3 scatti di “ruota giù”]

It is possible that the model still contains incorrectly connected objects. This can happen, for

example, if the user has forgotten to add suitable joiners, accidentally deleted an entity, or breached

the boltability or weldability criteria by shifting components from their original position.

Running the “Check coherence” command is therefore recommended; it can be found in the

Renode menu. It automatically checks for any connection problems between the various entities and

alerts the user accordingly. [esecuzione comando]

If we run the command, we are shown a message telling us that there are force

transferrers/cleats without a connection. [click]

The entities causing the problem are selected in the scene: the selected plate has no bolts or

welds to connect it to the members’ webs.


697 COMMANDS: RENODE – EXPORT DXF revisione: dicembre 2011

[vista renodo di un collegamento qualsiasi; aprire]

A model of the current Renode can be exported from CSE in .dxf format for use with

AutoCAD, IntelliCAD or similar systems.

The “Export” command, on the Renode menu, is available when Renode view is active.

If we are in “extract mode”, then only the currently extracted objects are exported;

otherwise, all the Renode’s components will be exported.

When the command is run, a dxf file is created in the same folder where the CSE model is

held. The file name is the model name followed by the mark of the corresponding Jnode. [callout:

nome_modello . CSE . AD . dxf]

This is how in the file created by CSE looks in IntelliCAD.

[spostarsi sul dxf e fare un rendering]


698 COMMANDS: RENODE – ASSIGN PRENODE

[Modello: Cmd_Renodo_AssegnaPrenodo.CSE, aperto in modalità LIGHT, versione ENGLISH, più di 1024x768]

The assignment of a parametric node, or p-renode, leads to the automatic construction of the

current node according to the operations done on a similar node saved in parametric form.

A parametric node can be assigned to a “blank” node: a node is blank if there are members

only (without any shift, trimming, extension, cut, bevel, etc.), there are no joiners, no cleats, no

additional variables or conditions.

If some operations have been already done, it is possible to restore the blank node with the

command Reset node content. [callout]

Use the command Assign Prenode to apply a parametric node to current blank node. A

dialog box shows all the p-renodes available in the archive that are similar to the current node.

[eseguire comando apertura dialogo]

Each p-renode has a description and some images. [ vari click ]

Some p-renodes could be reported twice or more times, with the same name but with a

different couple of numbers at the end: this means that the same p-renode can be applied in different

ways. Just assign the first one, and if it doesn’t give the expected results, reset the node and apply

the second one…

Generally, the p-renode we are going to assign must be coherent with current node: for

example a p-renode with hinged connections should not be applied to nodes with moment resisting

connections. It would be easy to add in CSE an automatic check of connection kinds in order to

prevent the assignments of p-renodes to nodes that do not have the same releases. This wasn’t done

because there are conditions in the middle between ideal hinges and ideal moment resisting

connections. That’s why we preferred to enable users to choose the proper connection for each

“real” condition, evaluating which is the most fitting structural scheme.


Once the p-renode has been chosen, click OK. [nodo _AC, premere OK]

The list of all the operations needed for the automatic construction of the node is shown:

these operations are the addition of components, the application of bevels and cuts, any change of

the members, the definition of new variables and conditions, etc. These operations can be modified

runtime, as shown later; now just press OK to assign the p-renode without changes.

[premere OK, eventualmente ruotare la vista, zoomare, ecc., infine tornare alla vista st. iniziale]

The node has been automatically constructed. User must check that everything is correct,

then he or she has to set and execute the checks.

User can also modify some components settings (for example, the just-shear flag or the slip-

resistance flag for bolts). [seleziona bullonatura, dialogo modifica, esci]

It is also possible to modify the geometry of the node, but the simplest way to do that,

specially when using the LIGHT version, is to re-assign the p-renode modifying the needed

parameters in real time.

Reset the node and re-assign the p-renode. [azzera – assegna prenodo, scegliere lo stesso]

The first time, in this dialog box we kept all the operations ticked. If we remove some ticks

the automatic construction of the node will stop where the operations are not ticked, and the user

will be able to modify the needed parameters.

The buttons All interactive and All automatic untick or tick all the operations that allow a

choice. Grayed out check boxes may not be changed because the operations that they refer to are

fixed. For example, the operations based on the clicking of a point or face in the scene are always

automatic and cannot be changed.

Untick the addition of the plate P1, since we want to modify its thickness, then press OK.

[bottone OK – attendere il dialogo della piastra e modificare immediatamente le quote: 1.5*m2.b,

1.5*m1.h, m2tf]


The automatic construction of the node now stops at the definition of P1 plate data. Sizes are

given in parametric form, using available variables, because the same p-renode applies to similar

nodes having different sizes; for example, the width of the plate depends on the with of member

number 2 (m2.b). When we apply the p-renode to a well-known node, we can also define data

simply using numbers, since we know the exact sizes.

The thickness of the plate is currently equal to the flange thickness of member number 2

(m2.tf). To emphasize the difference, let’s define a thickness equal to three times the current one.

[digitare 3*]

When we press OK, the automatic construction will be completed without other stops, since

there is not any other operation without tick. [premere OK – attendere – vista +y]

[callout: “Thickness has been overly incremented for more clarity”]

Now the plate is thicker than before and the position of the other components guarantees the

coherence of the node. Horizontal beams are shorter than before; bolt and weld layouts are placed to

fit current geometry. [salva video ]

Callout “FULL VERSION”

[Cmd_Renodo_AssegnaPrenodo2.CSE aperto con versione FULL]

In CSE FULL version, use the command Assign P-renode of the menu Renode to assign a

p-renode to current blank renode. [click bottone] From here on, the command works as in the

LIGHT version: it is possible to apply a p-renode without changes or to modify some operations.

[applica prenodo senza modifiche]

After the assignment of a p-renode, with the FULL version it is possible to modify and

customize the real node with the standard commands. User can add or delete components, add or

remove bevels and cuts, shift objects, etc.


With the FULL version, use the command Reset renode content from the Renode menu to

make the renode blank. [callout bottone, click] [ salva filmato ]

Let’s see some other applications of p-renodes. [carrellata]


700 COMMANDS: CHECKS – SET UP

[renodo, modalità FULL]

The Set Up command of the menu Checks is used to define general checks settings. It is

available when the graphical view is active in Renode mode. The command is mapped to a button in

the left toolbar. In CSE light version, the button is different, as shown at the end of this movie.

After the execution of the command, a dialog box is opened. [click]

The Standard is chosen in the first box.

The options for the output listing are in the box below. Choose the language, define a

complete or synthetic listing, tick or untick the box for listing-file automatic opening at the end of

the checks.

Internal actions computing mode can be set in the related box: it is possible to choose the

following different ways to set member internal forces:

- internal forces computed in imported FEM model combinations, if the model was imported;

- internal forces depending by factorized elastic or plastic limits of the members;

- values defined by the user for each member;

- combinations copied and pasted from a table.

If combinations from imported FEM model are used, it is possible to filter the worst

combinations: before executing the checks, CSE finds 24 worst combinations for each member of

the node, on the envelope of all jnode instances. These combinations are the one with maximum

internal forces for each member, considering contemporary forces.


When using elastic or plastic limits, a factor is set to multiply each internal force; for

example: 0.5 times the elastic limit for compression, 0.2 for tension, 0,3 for shear V2, etc. The same

for member 2 and so on. It is also possible to define, for example, a plastic limit with an

overstrength factor equal to, say, 1.2.

If using “Defined values”, you should directly type the values of forces and moments, in

current units. For example, compression can be equal to 200000N.

Elastic limits, plastic limits and defined values consider 24 combinations for each member:

12 single components (positive axial force, positive shears 2 and 3, positive torsion, positive

bending moments around axes 2 and 3, then the same considered as negative). Then, 12

combinations of axial force and bending moments are considered. See the guide for more

information.

The last mode is to copy and paste combinations from a table. Click the “from table” option

and a dialog box is opened. [click] Paste needed combinations copied from Excel or Notepad or

use the button Initialise 5 combinations to know the required format. [click] It is also possible to

type directly in the box or modify default combinations. For each combination there is a number of

rows equal to the number of current node members. Each row has 8 values: number of the

combination, number of the member, axial force, two shears, torsion, two bending moments.

Combinations number has no limits. You can use data from other programs or from external

computations, ordering them in CSE required format. Click OK to add the combinations. [OK]

In the proper box, define partial safety factors required by chosen Standard. If the Standard

is changed, the box changes too, according to needed data. [click]

In the Checks to be executed box, define which checks must be done and which must be

skipped. Options are:

- bolts pressure bearings

- punching shear checks

- block tear checks

- simplified checks for cleats

- neglect parasitic bending in bolts check (they are computed, anyway)


- members net cross-section checks

- user’s checks

Resistance check for bolts and welds is always done, as well as bearing surface check for

bolt layouts, if there are bolts layouts using bearing surfaces.

Now let’s see the box called FEM analysis of components. The following options are available:

- do not create automatic FEM models for any component;

- create just sketch models with nodes and forces, for the components having the FEM flag

ticked;

- create complete FEM models, for the components having the FEM flag ticked;

- create complete FEM models, for the components having the FEM flag ticked and execute

an automatic analysis. In this case, an utilisation ratio is automatically computed in each

combination, and it is compared with utilisations due to other checks.

It is possible to create and solve the automatic models using CSE, SAP2000 or another

program supporting sr3 format. This “other” program must be linked using the command “Settings”

of the “Modify” menu. See the guide for more information.

If using CSE internal modeller and solvers, it is possible to execute non-linear analyses. For

components having a non-linear material and the non-linear analysis flag ticked, CSE uses non-

linear solver Curan. For other components, linear solver Clever is used. Non-linear settings for

components can be defined during the addition of a cleat or during the modification of a cleat or a

member.

Use this button to set the options for non-linear solver. [click] See the guide for detailed

information about this dialog box. [close]

Finally, limit translation and rotation must be defined to allow for a warning message after

the checks. If these limits are exceeded at least in one of check combinations, CSE issues a warning.

Rotation is defined in radians; translation depends on current unit.


701 COMMANDS: CHECKS – CHECK RENODE

The Check renode command, available in renode view, runs the automatic checks on

current 3D real node. In the light version, this command is called Check node but it works in the

same way; see the end of this movie for more information.

Automatic checks are done according to the settings shown in the previous lesson.

Checks depends also by the “nature” of current node. For example, checks on members net

sections are not done if none of the members has a reduction of gross cross-section due to bolt

holes, cuts or bevels, etc.

Each component (member, cleat, bolt or weld layout) has some options that can exclude

some checks. For example, a single cleat or member can be excluded from automatic FEM checks,

even if in global settings the automatic FEM option is required; slip checks on a bolt layout are

done only if that bolt layout is marked as slip-resistant, etc.

Before the execution of the checks, CSE tests the coherence of all the connections. If there is

something wrong in the node, checks are aborted and user is informed about the problem.

If coherence check is ok, pre-requirements are tested. If there is at least a pre-requirement

that does not pass the test, CSE asks to continue with the checks or not. If there are not pre-

requirements or all the pre-requirements pass the test, then the checks are executed.

Automatic checks are done, including standard checks, user’s checks and automatic FEM

checks, if required.

The output listing is created and opened, according to checks-settings.

If displacements and rotations tests are not checked, proper information is given.

At the end of the check, the post processing tools are available.


[LIGHT VERSION]

In the LIGHT version, the command is called Check Node, and it has a different button. [callout]


702 COMMANDS: CHECKS –ENVELOPE, CURRENT RESULTS, ENQUIRE revisione: dicembre 2011

[modello: Cmd_Risultati_Fem.CSE; combi 1, ist.1]

This lesson covers three commands that provide information on the level of utilisation of the

various components. These are the “Envelope”, “Current results” and “Enquire” commands, which

are available from the “Checks” menu and from the side toolbar.

The “Show envelope” command presents a colour-coded view of all the components

together, according to their maximum coefficient of utilisation due to the various checks that they

have undergone, in all combinations and instances. [click]

It shows us at a glance whether there are unverified components and which entities are under

the greatest stress.

For each component, the “Enquire” command tells us the exact value of its maximum

coefficient of utilisation, what has caused it, and which combination and instance it occurs in.

[click] After invoking the command, we simply position the mouse cursor over any face of the

component whose utilisation we want to know.

[ membratura azzurra] For example, the maximum utilisation for this member is 0.605,

caused by the bearing stress in combination 37 and instance 2. [pausa]

[ bullone a dx] For this anchor bar, the maximum utilisation occurs in the pull-out check.

[pausa]

[ piastra di base] For the base plate, it is due to the resistance: therefore, the maximum

coefficient of utilisation is that computed via the automatic FEM analysis. [pausa]

[ blocco vincolo] For the constraint block, the main cause is the crushing associated with

the bearing-support check.

While the command is running, the view can be rotated, translated, zoomed, etc.

[spostamenti vari, visualizzazione di uno sfruttamento] To terminate the command, right-click with

the mouse or press the ESCAPE key.


The “Current results” command shows the components colour-coded by their maximum

coefficient of utilisation in the current instance and combination, for the various different checks.

[click]

As we scroll through the combinations and instances, the results are updated in real time.

For example, let’s look at combination 37, instance 2; this is where member m2 had its maximum

coefficient, as we saw. [combi 37, ist. 2]

We run the Enquire command again. [click] When the current results are shown, the

information is more detailed. The bearing stress causing the maximum coefficient of utilisation

corresponds to bolt number 2 in layout B2; the stress here is 411N/mm2.

[spostamento su un cordone] For the welds, for example, we can see the most critical point,

with the associated stresses.

In the next videos, we shall look at the results of the various checks that CSE performs.


704 COMMANDS: CHECKS – DISPLAY BEARING-SURFACE RESULTS revisione: dicembre 2011

[modello: Cmd_Verifiche_RisultatiContrasto.CSE, combinazione 4]

The “Show bearing-surface results” command is available in the Checks menu and as a

button in the side toolbar.

If the Renode has already been verified, then we can select the bolt layout with bearing

support that we are interested in and use this command to show the results for the support and bolts.

No other bolt layouts must be selected. [click]

We obtain a two-dimensional graphical view of the bearing-surface polygon, with the

corresponding bolt sections. The polygon and bolts are shown in the bolt layout’s principal

reference system. The local axes are displayed along with the projections of the global axes.

The compressed part of the bearing support is colour-coded according to the utilisation in

the current combination and instance; the part under tension remains white. The bolts are shown in

the colour that represents the utilisation due to axial force only; if the bolts do not operate on a

compression basis – as in this case – then those in the compressed zone will be white.

The utilisation values are shown for the bolt and the point on the plate with the greatest

utilisations. For the bolts, this is not the total utilisation – which also depends on the shear and can

be seen in the envelope – but only the part relating to the axial force.

The compressed zone is delimited by the neutral axis of the plane section subject to bending.

At the top left of the graphical view, we have the computation data: […] bolt layout name,

instance and combination, and the type of constitutive law used for the bearing support; […] axial

force and bending moments acting; […]the utilisation of the bearing support, and the maximum

stress in the support and in the bolts.


As we scroll through the various combinations and instances, the results are updated in real

time[click].


705 COMMANDS: CHECKS – DISPLAY NET SECTION RESULTS revisione: dicembre 2011

[modello: Cmd_Verifiche_SezNette_TER.CSE, combinazione 29]

The “Show net section results” command is available in the Checks menu and as a button in

the side toolbar.

If the checks have been set up to include the net-sections analysis, then this command allows

us to see the results for the sections of those members with reduced gross section for which the

check is required. If we select only the member that we are interested in and run the command, then

we get a two-dimensional image normal to that member’s most critical net section in the current

instance and load combination. [click]

In this case, it is net section number 4, [custom callout] where the flanges have been cut but

have no holes. For details on how CSE automatically recognises the net sections, please see video

630; for how the program computes the results, see video 352.

The image of the most utilised net section is coloured according to the levels of utilisation

(the colour scale is not identical to that used for displaying the overall utilisations, but is calibrated

according to the current maximum and minimum stresses).

Above the image, the following data are displayed: the Renode and member names, the net

section number, the current instance and combination; […] the internal forces in the net section

(axial force and bending moments); […] the maximum and limit normal stresses, and the ratio

between them.

As we scroll through the various combinations and instances, the results are updated in real

time. The most critical net section may be a different one … [ combi 30, combi 31]


[ combi 32]…and if the maximum utilisation in the current conditions has other causes,

then this is reported and no section is shown. In order to conserve disk space, only the information

for the significant checks is stored.


706 COMMANDS: CHECKS – DISPLAY FORCES revisione: dicembre 2011

[modello .Cmd_Verifiche_MostraForze.CSE, aumento dimensione azioni e font, combi 25]

After a Renode has been checked, we can use the “Display forces” command to show the

forces transmitted between the various components.

The command is available from the Checks menu and as a button in the side toolbar, when

the graphical view is active. [callout]

The forces and couples shown are those computed in the current instance and combination.

If an object is selected, then the actions displayed are all those that are transmitted between it and

all the unselected objects connected to it.

Hence no force will be displayed if no objects are selected or if all objects are selected.

If two or more directly connected objects are selected, then the forces transmitted between

them will not be shown – only those exchanged with the other unselected objects.

This model has already been checked, and the graphical view is active. We shall now run the

“Display forces” command, which will remain active until the button is clicked again. There are no

selected objects, so no forces are shown. Now we select the horizontal member [click]: the forces

transmitted between it and the bolt layout joined to it are immediately shown, in the current

combination and instance. In this case, with the elastic limit checks, combination 25 contains only

the axial force for the beam. As we scroll through the various combinations, the forces and couples

are updated in real time. [click fino a combi 31].

If we select the weld layout as well as the member, then the forces between these two

objects will no longer be shown; instead, we shall see those between the weld layout and the plate

[click]. The forces are shown at the weld layout’s centre of gravity; the same applies for bolt


layouts. If we unselect the member, then CSE displays the equal and opposite forces transmitted

between the weld layout and the plate, and between the weld layout and the member. [deselezione

membratura].

If we are working in extract mode, then all the forces transmitted between the extracted

objects and the unextracted ones connected to them are shown. [estrai – oggetti selezionati].

If we click the button again, the command is terminated. [click]


707 COMMANDS: CHECKS – DISPLAY COMPONENT FEM RESULTS revisione: gennaio 2012

[modello: Cmd_Verifiche_Risultati.CSE; in Sargon aperto il modello _solo_scheletro, reso icona]

The “Display component FEM results” command is available in the Checks menu and as a

button in the side toolbar. [callout] After the Renode has been checked, this command

automatically opens the FEM model for the selected component, if the system had been told to

create it. The selected program is used.

The FEM models can be created and automatically analysed using the CSE solvers, and the

results can be displayed using Sargon Reader, which is bundled with CSE. The Clever solver is

available for static linear analyses, and the Curan solver for nonlinear analyses.

When the FEM model is opened for the first time using the CSE command, the user is

prompted to save the model file; the file extension must be wsr. If the Renode is checked again, and

there is already a model with the same name from an earlier check, then the old .wsr file is

automatically overwritten when the “Display component FEM results” command is run.

[click, poi in post produzione tagliare le “sistemazioni” al modello] [Von Mises, inviluppo]

The models cannot be modified with Sargon Reader; however, holders of a Sargon licence

can modify the models manually by opening the model file directly in Sargon or by double-clicking

on the .wsr file. If this file has not yet been created, then the .sr2 file for the FEM model in question

must be imported into a new Sargon project.

If a finite element program with an interface to CSE is available, such as SAP2000, and if

FEM models are to be created by this program, then when the command is run, the model for the

selected entity will be opened using the version of the selected program in use.



------------------------------------------------------PARTE 2------------------------------------------------------

In part one of this video, we saw how to use the command for automatically opening the

FEM models created by CSE when it checks the connections. We are now going to take a broader

look at these models and how to analyse them.

For example, in the current Renode, a FEM model is required for the base plate [mostra

parametri piastra]. The mesh size required is 10mm in the areas around edges and welds, and

30mm elsewhere. The minimum angle specified is 19.8 degrees. The tolerance under which two

nodes are merged is 0.5 millimetres. [esc] The settings for the checks [click] require that a complete

model be created for automatic analysis in Sargon. Let’s analyse the Renode. [click]

In accordance with the settings, the static analysis of the FEM model is performed using the

Sargon Clever solver, in all the checking combinations and instances.

When the checks are complete, the post-processing is available. Because we wanted an

automatic FEM analysis of the model created by CSE, the system has also computed a coefficient

of utilisation for the component: it has compared the maximum Von Mises stress computed in the

FEM model with the material’s yield stress, scaled down according to the factor M0 as specified.

[inviluppo, interroga piastra] In this case, the maximum coefficient of utilisation has

resulted from the FEM check itself, as we can see: the cause is shown for the component as

“resistance”. If we had wanted the FEM model to be created without any automatic analysis, then

no coefficient of utilisation would have been computed from the FEM model.

We select the base plate and use the “Display component FEM results” command to open

the FEM model in Sargon Reader. [click]


The model would have been identical – albeit without the results – if we had set up the

checks in CSE to create the full FEM model without automatically analysing it. On the other hand,

if we had only wanted the “sketch” model, then the model would have been like the one we are

about to see [aprire il modello solo_scheletro].

When creating the “sketch” model, CSE uses the wireframe elements bordering the object;

nodes are included for the bolts and welds, and they are loaded with the correct forces in each load

case, which corresponds to a clearly specified checking combination/ JNode instance pair. In the

“sketch” model, any forces transmitted by a bearing surface are lost. Three of the nodes are

constrained, but these are dummy constraints used only to run the analysis, for the model is self-

balancing.

Let’s return to the full model [switch]. Here, we see not the object’s outline but the complete

mesh, made of plate-shell elements with the mesh size set in CSE and with the material and

thickness specified. [interroga piastre]

As well as the forces corresponding to the bolts and welds, there are also many small forces

simulating the pressure from the bearing surface. [vista x] We can show the forces without scaling

in proportion to the amplitude. [scala azioni –no –qualche secondo, poi scala si, vista isometrica]

If we asked CSE to automatically analyse the model, then the classic post-processing

features for a static analysis are now available: we can display deformed views and stresses in the

various combinations, analyse nodal displacements, and so on. [deformata, scorri tra casi di carico;

poi Von Mises]

The model created by CSE automatically includes a combination for each load scenario,

according to a unitary matrix. Thus in the results analysis, the envelope of the combinations

necessarily coincides with the envelope of the load scenarios. [inviluppo]

The maximum Von Mises stress, on the visible face of the elements and without removal of

scrap, computed for the various combinations, is 124.8N/mm2. [sforzi –faccia nascosta-inviluppo]

On the hidden face, it is greater: 129.6N/mm2. If we divide this value by the material’s yield stress –

355N/mm2 – then we obtain a coefficient of utilisation of 0.365. This must be increased if the

coefficient M0 is greater than 1. Because the plate is 25mm thick, there is no need to reduce the


yield stress. [callout con calcolo] Returning to CSE, we see that the coefficient of utilisation

computed automatically is the same. [CSE: inviluppo/interroga/callout]

-----------------

[modello Cmd_Fem_Membratura.CSE. Preparare un’istanza di sargon con aperto il modello fem

di m1; dietro alla finestra lasciare aperte finestre con il post processing; modello CSE

corrispondente aperto]

-----------------

[aprire modello CSE] We have just looked at the FEM model of a plate; we shall now

consider the model for a member with welded stiffeners.

In accordance with the settings, the stiffeners are recognised by CSE and are added to the

FEM model of the component that they stiffen. Let’s see the finite element model created, in

Sargon. [passaggio a modello Sargon]

We have all the load scenarios with all the forces transmitted by the various bolts, welds and

bearing surfaces – as for the previous plate. Here, the stiffeners are also modelled; they are

connected to the member using suitable elements that model the welds.

Let’s look at a few images from the post-processing. On the left, we have the deformed view

in one load scenario; on the right, the corresponding state of stress.

The system can create FEM models for members and components. To find out which cross-

sections are supported in the latest version of the software, please see the release notes.

Note that the forces applied are self-balancing for FEM models of force transferrers/cleats

only; in models of members, they are not. This is because the forces that a member transfers to the

Renode’s other components are equal to the internal forces in a single one of the member’s

extremities, namely the one joining at the Renode in question.


708 COMMANDS: CHECKS – DEFORMED VIEW, DEFORMED SCALE revisione: dicembre 2011

[modello Cmd_Verifiche_Deformata.CSE, combinazione 25, 2-3 scatti ruota giù]

After the checks have been run, the deformed view for the connection can be viewed in the

JNode’s various checking combinations and instances.

The “Deformed view” command is available from the Checks menu and as a button in the

side toolbar. It can be used when the Renode graphical view is active. [click su deformata]

Studying the deformed views is a useful aid to understanding the connection’s behaviour

under the various forces. It can identify design problems that had not been noticed earlier.

The maximum displacements are shown at the end of the results output listing, along with

the conditions in which they arise. Also, when the checks have been completed, CSE informs the

user if the maximum rotation or translation specified has been exceeded. The deformed views

complete the tools available for checking the displacements.

Note that each component is colour-coded according to its coefficient of utilisation in the

current combination and instance. [esc da defo, risultati correnti (callout), tornare a defo].

For a monochrome view, simply select all the components. [sel/ desel all]

The scale factor for the displacements can be changed using the “Deformed scale” command

in the Renode menu and on the side toolbar. [click]

As we scroll through the various combinations and instances, the deformed view is updated

in real time. [scorrimento tra le combinazioni].


709 COMMANDS: CHECKS – COMBINATIONS, INSTANCES revisione: dicembre 2011

[modello Cmd_Verifiche_Combi_Ist.CSE]

When analysing the results after the checks on a Renode have been run, we can use these

commands to browse through the combinations and instances in order to find out the results for the

components under the various conditions.

In practical terms, the commands work in the same way for combinations and for instances.

The commands are available in the Checks menu and as toolbar buttons. [callout]

We can move to the next or previous combination, or access a particular combination

directly (by calling up the list of all the combinations present and clicking on the one we want). The

current combination is shown at the bottom of the graphical view.

The same applies to the instances, when the Renode occurs more than once in the structure.

For example, if we look at the deformed view of the connection [click] and scroll through

the various combinations using the “next” and “previous” commands, then the view is updated in

real time, until we arrive at the deformed view for the current combination. [callouts]

If we use the “Combination” command, then a dialog box prompts us to select the

combination we want; when we click OK, this is set as the current one. [click]

The analogous commands are available for instances: so we can scroll through the next and

previous ones [click] or select the desired instance directly, using the dialog box [click].

This example has two instances only, but models may generally have numerous instances of

the same Renode.


We have just seen the commands in the context of the deformed view. They can also be used

to display the coefficients of utilisation in a particular combination and instance, or the forces

transmitted between the various components, or the results on the bearing support or on the

members’ net sections. All these results always apply to the current combination and instance.

[click vari… mostra forze, scorri, contrasto, scorri…]

There is a fixed number of instances, depending on how many times the connection occurs

in the model.

The number of combinations, on the other hand, depends on the internal forces used to

compute the connection.

If we opted (in the settings for the checks) to use the internal forces from the FEM model

imported via Sargon or Sap2000, then the checking combinations will be those from the original

model. This computation approach can be used only when a FEM model has been imported.

If, however, we wish to analyse the connection using the plastic or elastic limits, then the

number of combinations will be 24 times the number of members in the Renode.

With this computation approach, 24 combinations are created for every member, starting

with the master. Each one contains an elementary force or a suitable combination of elementary

forces, in order to reach the elastic or plastic limit, factorised as appropriate. For a detailed

description of the combinations at the plastic or elastic limits, please see the program user guide or

online help.

The commands illustrated in this video are mainly used to analyse the results in the Renode

view.

[vista fem, includi]


The commands for the combinations can also be used in the FEM view – if the model has

been imported – to inspect the internal forces in beams and trusses for different checking

combinations. In the FEM view, therefore, the combinations are always those defined in the original

model. These analysis commands are discussed in video 505.


710 COMMANDS: CHECKS – OPEN LISTING revisione: gennaio 2012

[file: outputfile.CSE.AA.EURO3.out; scorrere il listato durante la lettura]

The “Open listing” command is available from the Checks menu and as a button in the side

toolbar. It can be used when the Renode graphical view is active. It opens the output listing

containing the results of the checks that have been run on the current Renode.

The listing’s name comprises the following parts: the model name, the Renode mark, and the code for the standard used.

The file has extension .out and is a text file stored in the same folder where the CSE model is held. Full or cut-down

versions of the listing are available. We are now going to look at the full version.

The file starts with a glossary of all the terms and symbols used.

The name of the Renode is included (each one has a file of its own).

Hyperconnectivity is a mathematical indicator of the complexity of the problem in hand,

which uses terminology and concepts from the theory.

The units of measurement for the values in the listing are then stated. The units are those

active when the checks were run.

Then we have the settings for the selected standard, with the relevant parameters, and the

computation options.

There is a list of all the components in the Renode.


All the possible connections are listed; these are known as chains.

Then we have the general properties and computation properties for the bolt layouts.

The properties of the bolts in the various layouts are given in detail (all bolts belonging to

the same layout are the same).

If there are bolt layouts with bearing supports, then the parameters and computation settings

for the support are also reported.

The position of each bolt is given relative to the centre of its layout. Each bolt’s section

moduli are also stated.

For each bolt, the distances from the edges of all the drilled objects are included.

The weld layouts present in the Renode are listed ...

... followed by their computation properties and the positions of the individual welds.

If the user has set up any additional variables, these are also included in the listing.

If the user has set up any additional checking conditions or prerequisites, then these are also

listed.


We are now at the start of the section on the results of CSE’s automatic checks.

If user checks are required and have been specified in the settings, and if prerequisites have

been defined, then these checks are reported first; CSE performs them before the automatic checks.

During the analysis, if one or more prerequisites have not been met, then the system prompts

for confirmation whether the automatic checks should be run. If the user chooses to abort the

checks, then the listing ends here; otherwise, the results of the subsequent automatic checks follow.

The results for any prerequisites are listed; here, they have been satisfied.

Now we come to the forces acting on the bolt layout at its various extremities, listed in all

combinations and instances. The forces are expressed in the global reference system; they derive

from the finite element model created by CSE in the background to compute the connection. These

forces do not relate to individual bolts but to the entire layouts.

Next, the overall internal forces in the bolt layouts are shown; these are the forces

corresponding to the cross-sections for checking, in all combinations and instances.

This is followed by the internal forces in the individual bolts, in all instances and

combinations, along with the respective coefficients of utilisation according to the selected

standard.

For weld layouts, we have the internal forces in the various combinations and instances,

followed by the stresses in the individual welds and the associated coefficients of utilisation.

For the components, there are various lists, according to what causes the maximum

coefficient of utilisation in the various combinations and instances. These lists include the automatic

FEM checks and the user checks, together with all the other automatic checks that CSE performs.


For example, if the maximum coefficient of utilisation for a given plate in combination x

and instance y is due to bearing stress, then for that condition, the component will be listed under

“Throughs whose maximum exploitation is due to bearing stresses”. If the maximum coefficient of

utilisation for this plate, in combination j and instance k, is given by the automatic analysis of the

FEM model created by CSE, then this component will be listed under the “Throughs whose worst

exploitation is due to FEM resistance checks” for the condition “combination j and instance k”.

The results of the automatic check on the displacements are included, based on the limit

values set by the user.

Finally, we have a summary of the maximum utilisations computed for the various

components across the different combinations, instances and checks. (*) è necessaria una modifica

del listato

If the listing is produced in cut-down form, then only the essential information is included,

namely a summary of the components (without details of the bolt and weld layouts) and the

utilisation envelope with the maximum values for different combinations and instances.


711 COMMANDS: CHECKS – DISPLAY BLOCK-TEAR RESULTS

revisione: dicembre 2011

[versione in italiano – modello: blocktearing_tension.CSE, combi 25]

The “Show block-tear results” command is available both in the Checks menu and as a

button in the side toolbar, when the graphical view is active. [callout]

If the Renode checks include block tearing, and if the selected component’s maximum

utilisation is due to block tearing, then this command will bring up a dialog box showing the results

of the check for this component, in the current combination and instance. [esegui comando]

The image in the dialog box can be printed or copied to the clipboard. It shows the most

critical failure path on the selected component, based on the forces computed in the current

combination and instance. The currently selected face – shown in green – does not necessarily

belong to the component; to select the desired face, simply browse with the arrow buttons

underneath. The failure path terminates on the edges of the component whose results we are

viewing, regardless of the face selected in the dialog box.

In this case, the path computed causes the component to fail as shown in the pop-up. This

path affects only two of the layout’s three bolts; it is the most critical path, even though it is subject

only to a partial resultant. The CSE validation document studies this very case in detail, showing

that the most critical path is indeed the one computed by the program.

On the left, under the basic information, the following results are shown:

- the ultimate strength of the most critical failure path;

- the force applied, which may equate to the resultant of the whole layout or that of a subset of

bolts;


- the angle of inclination of the applied resultant, according to the convention shown in the

pop-up; [callout] magari scorrere con il mouse per fa vedere il 10-16

]

- the coefficient of utilisation given by the ratio between the force applied and the ultimate

strength of the most critical path.

For a detailed description of how the failure paths are computed and the problems involved,

please see the program user guide.


730 COMMANDS: PRENODE – NEW, SAVE revisione: dicembre 2011

[Cmd_Prenodo_Nuovo.CSE; renodo vuoto, vista grafica attiva, solo centri delle facce, pan.renodo]

Before learning how to construct a parametric Renode, it is a good idea to become familiar

with constructing a normal Renode.

In the parametric approach, the main difference concerns how the objects’ quantities and the

other data are defined: instead of entering numbers only, we can also use formulas, expressed in

terms of the Renode’s variables.

The command “New” in the PRenode menu starts the process of recording a parametric

Renode; it can be used when the current Renode is empty: in other words, if no components,

variables or conditions have been added, and no members have been modified. Using this

command, we can create standardised types of node (PRenodes) to save in the archive and use when

we need them. [ click ]

When the command is run, a dialog box appears for us to specify the new PRenode’s name,

the prefix for the associated images, and an optional description and explanation. The class and type

of the bolts to be used also need to be defined, using the button provided. [click bottone]

Once the data have been entered, we can build the Renode in parametric form by clicking

OK. [digitare “esempio” in nome e prefisso immagini, premere OK]

A button is available to save the PRenode during the recording process [callout].

We shall start to build our Renode, which will be a ground joint, by adding a base plate.

[arrivare fino al dialogo delle quote]


During the recording process, we can define the plate’s dimensions using formulas.

We define the plate’s width as twice the width of member m1; similarly for its height.

[digitare “2*m1.b” e “2*m1.h”] We make the plate as thick as the flange of m1. [digitare “m1.tf]

These data are mere examples to keep things simple; they are not intended to optimise or

design the connection. [callout] We update the image based on the quantities entered. [aggiorna]

We insert the plate into the scene. [...]

We shall not construct the entire connection now, because that is not our aim in this lesson;

we shall save a connection that contains a plate only. First, however, we’ll save an image to

associate with the node once built. [add image]

We save the current PRenode into the archive, using the Save command, and we exit from

parametric mode [salva].

The freshly saved PRenode is now available in the archive. [aprire l’archivio e mostrare,

esci]

We shall now apply the PRenode to a different Renode. We open a new model and quickly

define a ground joint with a similar section of different size, for instance a HEB200. [nuovo

modello, strutture tipiche….]

We apply the PRenode saved earlier. […] As we can see, the plate size has changed for the

current member.


Although only a plate has been added in this PRenode, complex PRenodes can be created,

without restrictions on the number of entities or the operations to perform.

An existing PRenode can also be revisited using the Restart command, which is described

in a lesson of its own.


731 COMMANDS: PRENODE – RESTART revisione: dicembre 2011

[prenodo compatibile vuoto]

The Restart command allows us to add new operations to an existing PRenode from the

archive.

To use this facility, we need to work on an empty Renode that is compatible with the

PRenode that we wish to amend. An “empty” Renode is one with members only, without any

modifications or new components. “Compatible” means that it must have the same topology and

the same types of cross-section as the PRenode that we wish to modify.

Once the command has been invoked, the user is presented with the archive from which to

choose the PRenode to work on. If no PRenode is compatible with the current Renode, then a

warning message is shown. [click]

If there is at least one compatible PRenode, as in this case, then we select the PRenode that

we want, and we apply it, as if assigning a parametric Renode normally. [selezionare prenodo,

OK]

We can edit some of the parameters, if we wish, or we can apply the PRenode as it is. [OK]

The PRenode has now been applied, and we are in recording mode. The dimensions of the

components, the magnitudes of the shifts, and so on, must be defined parametrically. The operations

performed will be saved against the original PRenode, which will therefore contain all the existing

operations as well as the ones just added.


As in a normal recording, images can be added, the recording can be paused and resumed,

the PRenode can be saved with its new additions, or the recording can be aborted and the changes

discarded.


733 COMMANDS: PRENODE – ADD IMAGE revisione: dicembre 2011

[nodo qualsiasi già finito, in modalità restart per avere il comando disponibile]

When recording a parametric Renode, we can use the Add image command on the PRenode

menu to save the current view in JPEG format and associate one or more images with the current

PRenode. [ salva img ] The image must be saved in the CSE installation folder, which is offered

by default. The default name offered for the image consists of the prefix chosen at the start of the

recording process, together with a progressive number (appended automatically).

The command is intended for use after the PRenode has been completed – to create a full set

of useful images for it. Images of extracted views can also be added, along with zooms of details

and anything that may help to document the PRenode.

New images can also be added to an existing PRenode through the archive.


735 COMMANDS: PRENODE – PAUSE, CONTINUE, ABORT revisione: dicembre 2011

[nodo qualsiasi già finito, in modalità restart per avere il comando disponibile]

During the process of recording a parametric Renode, the Pause command can be used to

suspend recording and return from parametric mode to standard mode. [click] None of the actions

taken during the pause are recorded in the PRenode. To resume recording, use the Continue

command; this returns control to parametric mode. [click]

During a pause, we can perform operations that we do not want to record, like testing a work

process or making modifications. It is important that these operations do not interfere with the

recording, when we resume. The following example should clarify this. Suppose that, during a

pause, a new component is added – plate P1, for example – and that, on resuming after the pause,

we add a weld layout on that plate. Clearly, applying that PRenode would create an inconsistency,

because we saved the weld layout onto a non-existent component, for this component was defined

during a pause and has not therefore been saved.

Using the Abort command, we can terminate the process of recording a PRenode without

saving it. Any entities, work processes and modifications added will remain on the current Renode,

but they will not be recorded. At the same time, control reverts from parametric to standard mode.


739 COMMANDS: PRENODE – ARCHIVE revisione: dicembre 2011

[modello qualsiasi, ma anche modello vuoto]

The Archive command, on the PRenode menu, gives access to the archive of parametric

Renodes – or PRenodes – via a dedicated dialog box, which appears when the command is run.

[click su bottone]

All the PRenodes in the archive are listed in the panel on the left. The image shown is the

first one associated with the selected Renode, highlighted in blue. If there are several images

associated with it, then these can be scrolled with the arrow buttons. [click] The Open button opens

the current image in Paint, so that it can be viewed in its actual dimensions and modified (if

desired).

With the Remove button, we can dissociate the current image from the PRenode to which it

relates. We are prompted whether to remove the link or to delete the image as well.

The Add button allows us to associate a new image to the current PRenode, by specifying

the file path.

We now come to the buttons in the “Actions on selected PRenode” section. [callout] We

can save our work by clicking the OK button and discard it by clicking Cancel.

The Remove button deletes the currently selected PRenode; the user is prompted for

confirmation first. Duplicate creates a copy of the selected PRenode and puts it at the end of the list;


this copy can then be modified using the Restart command on the PRenode menu or via the

alphanumeric mode. Modify or display initial data brings back the dialog box used to start the

process of recording a new PRenode and specify some preliminary settings. [click] Here we can

change: the name of the current PRenode; the prefix associated with its images; the description; the

explanation; and the bolt class. [esci] Modify operations allows us to modify the current PRenode

alphanumerically. [click] Effectively, this means editing an ASCII text file.

[scorrere su un componente] For example, we can change a component’s dimensions by

altering the text. To save the changes, click OK in this dialog box and again in the main one.

Finally, let’s look at the buttons in the “Actions on archive” section. [callout]

Add new PRenodes from file prompts the user for a text file containing new PRenodes; Save

PRenodes onto a file (txt) enables us to create a text file containing all the PRenodes in the archive.

Using these two commands, and by editing the text files that are created, we have a means of

managing and customising the archive – for example, by organising the PRenodes into different

sub-archives.

Save PRenodes onto a file (bin) allows us to save the current archive into a binary file – as a

backup copy, for instance.

With the command Clear all PRenodes from the archive, we can empty the current archive.

This operation – like adding PRenodes from a file – is confirmed when we click OK.


801 PROBLEMS: Bearing support – Bearing surface

In this video, we discuss how to define a bearing surface. The concept was introduced in lesson

205, which defines what a bearing support is and what role it plays.

A bearing support works by exchanging normal compressive stresses between two or more

surfaces.

In order that these stresses can be transmitted efficiently, it is essential that the bearing support is

stiff enough.

The contact surface between one plate and another – or between a plate and a constraint block –

can, in general, exert compressive stresses. Its stiffness, however, will generally vary from one

point to another (exactly as a plate’s deformation varies under a constant pressure).


The bolt layout’s bending, which the bearing support helps to absorb, is normally exerted by an

initial surface, called the applied load footprint; this is generally the transverse section of a

member. The bending is transferred from this initial surface to the bearing support, thanks to the

bending stiffness of the plate to which the bolt layout is connected. In order that this plate can

successfully transfer the normal stresses involved, it must be sufficiently stiff.

The plate’s stiffness depends on its thickness and on the geometry of the connection. A plate

will be stiff enough in all its points if it is thick enough.


In this case, the bearing surface can be the entire surface of the plate to which the bolt layout is

connected.


A thin plate tends to bend easily, and only a small area of it in the neighbourhood of the applied

load footprint can fulfil the role required. We can improve its stiffness locally by adding stiffening

plates to connect the plate to the member that causes the bending. If enough of these stiffening

plates are used, then the entire surface of the plate – despite its thinness – can successfully transmit

the normal stresses and can thus function properly.


The normal compressive stresses needed to absorb the bending are pressures normal to the middle

plane of the plate; they can be thought of as a load applied to it. The figure shows the forces

exerted on the plate by the weld layouts and the pressure exerted by the bearing support.


A model adopted by the most recent standards offers a very useful aid to understanding which part

of the plate may act as a bearing support; in this approach, the surface of the applied load footprint

is extended by a certain width around the edge, determined by the plate’s thickness and by other

parameters. In this model, the stiffness is required only in part of the plate, namely that obtained

using this geometrical construction.


In a cantilevered beam, the stiffness depends on the inverse of the cube of the beam’s span. The

shorter the beam, the greater its stiffness. The same consideration applies to the plate to which

the bolts are connected.


The cantilevered beam’s span is comparable to the width to be added to the surface of the applied

load footprint. This span depends directly on the thickness of the plate.


When stiffening plates are present, the surface of the applied load footprint is not just that of the

member’s transverse section: it includes the contact surfaces of the stiffening plates as well. The

figure shows two long stiffening plates connecting the column to the base plate. The adjacent white

rectangles represent the welds.

These issues must be considered when we define the bearing surface; the designer is responsible

for specifying a realistic bearing surface. CSE provides the user with a full set of tools for

defining it. It may be one of the coplanar faces in contact, perhaps with a suitable additional border,

or it may be the result of any sequence of Boolean operations applied to surfaces of this type.

CSE determines the extent of the portion to be considered, in the neighbourhood of an applied load

footprint, using the formula in Eurocode 3.

Let’s reflect for a moment about what can happen if the designer specifies the bearing surface

incorrectly – for example, as the entire contact surface of a fairly thin plate without stiffeners.


In this case, the entire contact surface needs to resist the compressive stresses. The non-linear

computation will say which part of the surface will be under compression (and therefore reacting)

and which part will be under tension (and therefore not reacting). Here, the yellow area is the

reacting part.


When the plate’s resistance is checked using the FEM model, however, the compressive stresses

exerted by the bearing support will become normal pressure loads in the model of the plate,

which will be bent. Note the (unscaled) forces corresponding to the normal pressure exerted on the

plate in turn in the compressed area of the bearing support, shown in yellow in the previous image.


There will be a certain set of stresses on the compressed side of the plate (Von Mises stresses),

depending on the pressures on the bearing support and, of course, on the plate’s thickness and on

the mesh used for the computation. If the plate is too thin, then it will bend excessively and will not

be able to bear the load. In this example, the welds are considered as clamps (magenta-coloured

dots).

We can now see what would have happened if the bearing surface had been a smaller surface,

consisting of the applied load footprint with a border added around it, as illustrated.


The non-linear computation would have given a different compressed area, typically closer to the

welds. The reacting part, in yellow, is clearly not a rectangle but T-shaped.

This is how it compares to the previous situation.


The part of the plate under compression is now smaller, and the Von Mises stresses in it do not

exceed the yield value.

To sum up: if we choose a larger bearing surface than is realistic, then the plate will be under much

greater stresses, because the areas of normal pressure will be much larger than necessary.

The next lesson discusses the constitutive law for the bearing support.


802 PROBLEMS: Bearing support – constitutive law for the bearing

support

Once a bearing surface has been defined, we also need to specify its constitutive law.

The bearing support exerts a distribution of normal compressive stresses through the bearing

surface; this distribution combines with the tensions in the bolts to balance the axial force and the

bending applied to the bolt layout.

These compressive stresses observe a uniaxial constitutive law that governs the stresses and the

deformations. The distribution and the magnitude of the compressions depend on how this

constitutive law is defined.

For a given bearing surface and number of bolts, the combined tension and bending or the

compression and bending applied is balanced differently depending on the uniaxial constitutive

laws used for the bolts and for the bearing support. The computation is non-linear.

The constitutive law for the bolts is elastic-perfectly-plastic. Therefore, if one or more bolts reach

the yield stress, then the computation redistributes the tensions from the bolts that have yielded to

those that still have not. If all the bolts have yielded, then the load exceeds its allowed limit, and

convergence is not possible. In this case, the bolt layout cannot sustain the forces applied.


The bearing support’s constitutive law is no-tension and is therefore always non-linear. Only part

of the bearing surface reacts; the rest of it does not. The compressed zone can react, in the part

under compression, according to a linear or a non-linear constitutive law.

If the compressed part is linear, then we need to state the factor m that, when multiplied by the

bearing support’s modulus of elasticity, Ec, gives the modulus of elasticity for the bolts. If m is

large, then the bearing support is less rigid than the bolts; if m is small (less than 1 – even

significantly so), then the bearing support is more rigid than the bolts.

As m increases, the part of the bearing surface affected by the compressive stresses increases in

size; indeed, for the same deformations, the normal compressive stresses exerted by the bearing

support become smaller.

Conversely, as m decreases, the part of the bearing support affected by the compressive stresses

decreases in size, although the stresses exerted become greater.


Users can define not only linear laws but also elastic-perfectly-plastic, parabola-rectangle or

trilinear laws for the bearing support.

Sometimes, a bolt layout anchored to a plate that is subject to bending may exert a rotational force

on it about one of its corners. This behaviour can be simulated using a constitutive law that makes

the bearing support much stiffer than the bolts (for instance, by setting m=0.01, or 0.001 if linear).

To see what this means, let’s suppose that the bearing surface is shaped like this.


And let’s start by setting m=1.

In a combination where there is only bending moment at the section’s elastic limit, we obtain the

following distribution:

If we now set m=0.01 and repeat the computation, with the same forces and the same bearing

surface, then we obtain the following:


In effect, this simulates the rotation about the lower side of the bearing surface. The affected part of

the bearing surface is much, much smaller, yet the peak stress is almost 10 times greater (4.375

times the bearing support’s limit stress, compared to 0.495 times in the previous case).

Now let’s set m=10, considering the elastic modulus of the bearing support to be one tenth that of

the bolts.

The resulting distribution is as shown. The part of the bearing surface under compression is larger;

the peak stress is lower (0.210); and the normal stress level of the tension bars is much greater

(because the arm of the internal couple is now smaller).


805 PROBLEMS: Shear-only bolts

When designing connections, we often need to consider bolt layouts acting through a resistance

mechanism under which the bolt shafts are ideally not under tension or compression. Such bolt

layouts can withstand only shears and twisting moments (in other words, only offset shears), by

means of a shear in the bolt shafts.

Such bolt layouts are described as shear-only; we can deploy them by ticking a dedicated field in

the dialog box used to add or modify bolt layouts.

Shear-only bolt layouts have very limited bending stiffness in the CSE computation model. If a

bending moment acts on such a bolt layout, then unless the moment is very small, it will cause high

displacements – even if the bolt shafts are only subject to the tension and compression forces that

are essential to maintain equilibrium.

When this happens, the bolt layout cannot work on a shear-only basis; instead, it must be treated

as capable of withstanding bending moments too (it must not be shear-only).

Theoretically, there are only two ways for a bolt layout to be shear-only: either bending moments

are absent or they are absorbed by other shear-only bolt layouts or other joiners that work together

to absorb them.

In reality, no bolt layout is free of bending moments. Even where normal technical practice is to

neglect the weak moments of transport of the shears, caused by the (albeit modest) plate

thicknesses, these moments do exist in CSE’s computation model, and they give rise to (generally

modest) bending moments. Besides, a shear always generates a bending moment at a certain

distance.

[colonna con cerniera alla base]

If the bolt layout is iso-connected, or statically determined (see lesson 810), and if the connection

is completely free of bending moments (as in a hinge), then the bolt layout may be shear-only.

[collegamento a squadretta trave-trave, incernierata]

If the bolt layout is iso-connected, and if there are very small bending moments – due to the

transport of the computation shears over small distances – then we have two options.


Either we leave the bolt layout as shear-only, neglecting the potentially high displacements

highlighted by the software;

or we transform the bolt layout into a non-shear-only bolt layout, but without specifying any

bearing support. In this case, the (parasitic) bending due to the transport will be absorbed by a

modest tension and compression in the bolt shafts; this will not invalidate the checking

computation.

If the bolt layout is hyper-connected and several bolt layouts work together to bear all the

computation forces, then the bolt layouts may be shear-only – but only if the bending moments in

the computation are absorbed by two or more bolt layouts that (although shear-only) bear the

bending moment applied essentially by a couple of forces (shears in the bolt layout).

If there are no such cooperating bolt layouts – or if there are, but they are poorly arranged – then

the program computes highly significant displacements; the designer will then need to revisit the

connection design.


810 PROBLEMS: Flexibility index for bolt layouts

Generally, most bolt layouts fulfil a precise static function, and the stresses on them can be

determined by simple considerations of equilibrium. Such a bolt layout is said to be iso-connected

(or statically determined).

Otherwise, where several bolt layouts combine to bear a certain set of stresses, the layout is said to

be hyper-connected (or statically indeterminate).

Experimental investigation has shown that the stresses borne by a hyper-connected bolt layout

depend also on complex factors like bearing stress (the plasticization of the sheet due to shear in the

bolt shafts), friction and the play between the bolts and the holes.

Forces borne globally by two or more bolt layouts therefore tend to be redistributed between

layouts; they migrate from the bolt layout that caused the bearing stress in the sheet or that has a

greater play between bolts and holes.

The computation methods currently in general use tend to address these complex phenomena in a

conventional and one-size-fits-all manner; to take them into account properly, CSE has introduced

the concept of the flexibility index for a bolt layout.

For each bolt layout in CSE, a native stiffness can be computed that depends on various factors,

like the number of bolts, their separation, their diameter, and the bolt layout’s position. If a bolt

layout’s flexibility index left unchanged as the default value of 1, then the forces that two or more

bolt layouts must bear are distributed among them in proportion to their native stiffnesses.

In certain cases, the plasticization and redistribution that we have just mentioned cannot be dealt

with properly just by sharing the stresses between the various bolt layouts, as predicted by native

stiffnesses.

To modify how the stresses at a set of hyper-connected bolt layouts are shared out, we can increase

the flexibility index for one or more bolt layouts, thus reducing their stiffness from their native

value. This simulates the redistribution due to the plasticization that we mentioned.


In some cases, therefore, it can help to increase the flexibility index for certain bolt layouts from the

initial value of 1 up to 3, 5, 10 or more.


820 PROBLEMS: Checking stiffeners

In CSE, stiffeners are components that transmit forces from one part of a component to another part

of the same component.

They must not be confused with the stiffening plates or components that connect different

components.

What we are referring to are mostly stiffeners for I- or H-sections

or reinforcing plates, such as for webs (in moment-resisting connections).

Neither the stiffeners themselves nor the joiners used with them are subject to CSE’s automatic

checks.

Normally, stiffeners do not need to be checked numerically; they are simply sized appropriately,

generally according to the dimensions of the component that they stiffen.

Nevertheless, they can be checked by CSE, when necessary:

by suitable custom user checks or standard checks;

through the FEM check on the component that they stiffen.

It is the user’s responsibility to ensure that these components are checked when required.


825 PROBLEMS: FEM modelling – general remarks

Although the checks on bolts and welds follow established rules that are essentially well defined

and standardised, the checks on the components are much more complex. This is because the

resistance mechanisms that arise in a component depend on its form, on its dimensions, and on how

it is connected to the other components.

Other checks (bearing stress, punching, member net sections, etc.) can be formalised, to a certain

extent. Others are so complex and general that a full finite element model of the component is

useful for stress analysis purposes.

This approach is not mentioned in the standards, because a T-stub model is usually recommended

instead, despite its clear defects and failings. Firstly, it lacks generality – bolts must be regularly

arranged in two rows, etc. Secondly, the simplification involved – compared to actual practical

problems – is drastic. Thirdly, it is unwieldy and computationally complex. The T-stub-model

approach involves a limit analysis using slip-line theory.

The finite element method has advantages and disadvantages.

One disadvantage is the computation time, although it can be reduced using sparse-matrix solvers

like CSE’s, especially in elastic scenarios. Another disadvantage is the need to examine the stress

analysis results in order to decide whether the entity is acceptable in engineering terms.

Furthermore, the FEM model of the components is conventional, and to a certain extent –

specifically for welded and bolted connections – it is still subject to ongoing research.

Its greatest advantage is generality, which enables us to address any problem in an essentially

precise manner (within the limits of a numeric approach). Although the models are conventional,

both the bolts and the welds can be modelled to give good safety results. The stress maps are,

therefore, a much more sophisticated and accurate tool than T-stub models, which refer to

elementary stress scenarios and are geometrically not very general.

In the checking approach that uses finite element modelling, we need to remember that some

potential failure modes are already considered by other checks, like bearing stress or block tearing.


Unlike the approach envisaged by the standards, no load limit is calculated for comparison with the

applied load. The applied load is applied to the entity, and we examine the resulting state of stress to

judge if it is acceptable.

In the T-stub checks under Eurocode 3, part 1-8, the check involves applying somewhat simplified

limit domains between the elementary components of stress. For example, if there is an axial force

and a moment, then the limit axial force and the limit moment are evaluated, then a limit domain is

defined by linearising.

On the other hand, the FEM checks apply the axial force and the bending moment of each

combination at the same time (as well as any other stresses present), to determine the corresponding

state of stress. The approaches are therefore completely different, even though they are doing the

same thing, from an engineering standpoint. Even if not explicitly provided for under the standards,

the checking approach that uses a FEM model is more rigorous, by definition, and aims to achieve

the same results.


826 PROBLEMS: FEM modelling – linear vs non-linear

The usual approach in the most recent standards is to compute the limit (plastic) forces and compare

them with the existing ones. Yet the existing forces will not necessarily fully plasticize a

component.

It is always good to run the linear analysis first, because it is much simpler and faster than a non-

linear one. This helps us determine whether the entity has reached its plasticization limit.

Given that bearing stress is already taken into account in other checks, minor plasticizations around

the nodes that simulate the bolts are normally acceptable. Even if there are stress peaks around these

nodes, we shall not discard the entity.

Conversely, if plasticization affects large areas of the component, then we can conclude that a linear

analysis will not be enough. It is not always useful, however, to start with a non-linear analysis.

This is because, when plasticization spreads in an elastically calculated entity, it is likely that a non-

linear analysis would also have the same outcome: discarding the entity and redesigning it.

The non-linear analysis can be useful when the plasticization predicted by an elastic computation is

moderate – when it is not confined merely to the areas around the bolts or welds, but nor does it

spread across the entity’s entire surface.

Therefore, it will be useful here.

The non-linear analysis is longer than the linear one, because the computation is iterative.

There are two basic approaches, depending on the constitutive law used for the metal.

Under the elastic-perfectly-plastic constitutive law, the analysis aims to achieve convergence using

the full applied load. If this occurs, then the load limit has not been exceeded, and the component is


acceptable. On the other hand, if the applied load is not reached (because the solution diverges), or

if it is reached but only with unacceptable displacements, then the component must be redesigned.

If we use a hardening constitutive law, then convergence will be achieved anyway, and there will be

two conditions to examine. One is to check that the ultimate stress is not reached at any point. The

other is to establish that the displacements under the applied loads are not excessive.

For a component whose FEM model has been created, we analyse its state of stress by considering

its Von Mises stresses. This is done by the Sargon Reader utility program, which is supplied with

CSE. The available functionality includes the ability to view the Von Mises stress envelope map for

all combinations. This immediately tells us the peak stresses that have been reached, and in which

areas and combinations they occur.


830 PROBLEMS: Selecting your checks and how to run them

The choice of which checks to perform and how to perform them is a crucial step for any

designer of connections, irrespective of CSE.

CSE provides a full toolset for simplifying, speeding up and enhancing the connection designer’s

work. Except for the provision of standard ready-made PRenodes, it cannot do the designer’s job

for them (and does not try to).

Depending on the problem in hand, some checks will need to be made, while some can be omitted.

The checks made depend also on the types of weld layout chosen and how the bolt layouts are

going to work.

Some checks are automatic and require no user intervention at all. Others need the user to enter

information.

Once a bolt layout’s mode of operation has been decided, the bolt checks in CSE are fully automatic

and require no user intervention at all. This also applies to weld layouts.

The components, members and force transferrers/cleats, joined by bolt and weld layouts, may

actually need a great many different checks, depending on how they are constructed and the static

role that they play.

The bearing-stress checks are automatic and may be run or omitted, according to requirements.

The punching checks are also automatic and may be run or omitted.

The block-tear checks are automatic and may be run or omitted. Because block tearing is an

extremely complex problem, users should check that the failure path found by the program is

acceptable.

The group of “component strength checks” offers numerous potential local checks, depending on

the problem in hand. The user is responsible for deciding which checks need to be run and which

can be omitted; CSE offers a huge range of automatic and semi-automatic tools to cover any

eventuality.


The member net-section checks belong to this group; they are automatic and are run on

request.

The component FEM checks are automatic and are run on request. They are for complex

problems and very important components. They also belong to this group of checks.

The standard checks include special checks that belong to this group; they are run on

request, as user checks.

The simplified checks on the force transferrers/cleats belong to this group and are useful

for certain types of entity. They are run on request only.

User checks can always be added to provide particular checks in this group. They are also

run on request only.

The group of “component stability checks” is restricted to a small number of cases, given that they

are usually addressed implicitly in determining the relative sizes of the entities. There are two ways

to perform this kind of check in CSE:

some standard checks cover specific stability checks: for example, the stability of the web

panel;

user checks can be added for any special stability checks that may become necessary.

Many checks do not involve computations but are automatically fulfilled when the user gives

the components the correct sizes.

The vast majority of the checks that require computations are supported by CSE as standard. There

are cases, however, where the user must add some checks via the “user checks” tool.

Ready-made parameterized nodes should also contain all the settings needed to perform all the

checks.


840 PROBLEMS: Parameterizing Renodes

Parameterizing Renodes is an important feature of CSE. It enables users to create parametric

Renodes for application to whole families of empty Renodes.

One obvious group of settings to consider when parameterizing involves the physical dimensions

of the components. These dimensions can be expressed using formulas instead of numbers. These

formulas can use not only the predefined variables but also those added by the user.

For bolt layouts, the number of bolts and their diameter can be parameterized, and so can the

separation between the rows and columns or the layout type. The choice of the bolt layout’s

static operation, the bearing surface and other information are also parameterizable.

For weld layouts, the number of welds, their length and thickness can be set as parameters.

So can the spatial arrangement of the components, in that the layout can be tailored to suit the

different situations at each of the Renodes to which the PRenode can be applied.

And it’s not only the PRenode’s geometrical construction that can be parameterized. So can the

choice of checks and the addition of user variables and standard or user checks.

The use of parameters allows CSE to create complete, ready-to-use Renodes quickly and easily.

This feature is also available in the LIGHT version of the program (that is, the availability of ready-

to-use PRenodes).

Parameterization requires an effort to generalise the design, given that we are describing not a

single, individual Renode but rather an entire family. Designers have the freedom to use different

parameterizations, depending on their needs.


901 Defining a node with the light version Revisione: novembre 2011

[CSE LIGHT, modello vuoto]

Two steps are needed to define a node with the LIGHT version of CSE, starting from a new

model. The first one is the choice of a structural scheme among the available ones, with the

definition of material and the cross-sections. The second step is the assignation (assignment)

of a predefined node of the archive, with the automatic addition of bolts, welds, plates or

other components according to the chosen node. These predefined nodes are parametric, in

order to fit current sizes; the user can modify desired parameters.

Use the command “Typical nodes” to define the structural scheme. This command is under

the menu called “Nodes” and there is also a button in the bar. It is available if the graphical

view is active. Just click it to activate it. [click vista grafica] [click typical nodes]

A property sheet shows all the available schemes. Now we are going to define, for example, a

beam-column joint. [click] Red members are the masters of each node. Choose the node

with a column and two beams. [click secondo schema]

Use this dialog box to define members properties.

It is possible to add a new material or to browse the archive. All the members will have the

same material (with the light version it is not possible to define different materials for the

members of the same node).

Now browse the archive [click] and apply the S235. [applica il materiale]

It is possible to add new cross-sections or choose from the archive. Now browse the archive

[click] set a filter on HEB type [click] and see all the available cross-sections [click]

Apply, for example, the HEB 280. [click]

This cross-section is now the current one. Apply it to member 1, which is the column. [click]


Now set as current section an IPE shape. [click, IPE270] Assign IPE 270 to the beams.

[click - click]

It is possible to define hinged connections between the slaves and the master.

It is also possible to apply a rotation of 90 degrees to the cross-sections, if the corresponding

boxes are unticked.

Click OK to get the node. [ok]

If the model was not saved at the beginning, the program asks to save it now. [salva]

Now we have a “blank” node, with unconnected and overlapping members. The next step is

the assignation (assignment) of a predefined parametric node choosing it from the archive.

Here this operation is briefly shown; see movie 6 9 8 for more information.

Use the command “Assign p-renode”. [click] All the available parametric nodes similar to

current node are shown in the list. Choose one of them and assign it. [ultimo collegamento,

OK] Parameters can be modified during the automatic assignation (assignment); now just

leave default values. [OK]

The node is ready for a control by the user, and then for the setting and the execution of the

automatic checks.

steel connections software program cse: text of multimedia

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