manual of static and dinamic analysis 2014

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M NU L OF

ST TIC ND DIN MIC N LYSIS

According To

NTE E.030 – ASCE/SEI 7-10

Alex Henrry Palomino Encinas



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The present work aims to serve as a guide to the professional and student of civil

Engineering and related fields for the correct use and analysis by computer using the

program ETABS version 2013.

Procedures have been established by means of steps and sequences to follow,

starting with the description of the structure including dimensions established by pre-

dimensioning and design criteria, and then perform the modeling of the full structure,

taking into account the criteria of modeling for a behavior closer to reality and to

proceed with the run of the analysis to determine the different initial parameters and

calculate properly the static shear at the base, known as the Lateral Force

Equivalent, FLE, in addition to the calculation of its distribution by floor. It is also a

procedure similar to the analysis that incorporates a design spectrum, called Modal

Analysis of Response Spectral, AMRE. Both procedures are performed considering all

the parameters set in the NTE E.030 of earthquake-resistant Design of Peru.

We performed manual calculations to verify the accuracy of the results obtained

with the program, which demonstrated the power of the program and the great

help that we have when he knows how to give a proper use and boundary

conditions recommended to the model.

This work has been done to be worked on with the tutorial videos posted and the

information contained in this manual will be updated and re-edited constantly so as

not to lose the value of academic and professional that you may have.

Alex Henrry Palomino Encinas, 2014

© 2014 by Alex Henrry Palomino Encinas®. Manual de Análisis Estático y Dinámico

según la NTE E.030 subject to the license attribution-Noncommercial-Sharealike 4.0

International Creative Commons. To view a copy of this license, visit

http://creativecommons.org/licenses/by-nc-sa/4.0/.

For the avoidance of doubt, by applying this licence the Autor does not waive any

privileges or immunities from claims that it may be entitled to assert, nor does Alex

Henrry Palomino Encinas submit itself to the jurisdiction, courts, legal processes or laws

of any jurisdiction.

Manual de Análisis Estático y Dinámico según la NTE E.030.

Prepared by Alex Henrry Palomino Encinas.

ISBN



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Shear Static and Dinamic at the ase

Manual Calculation with ETABS 2 13

[5]

1. INITIAL CONSIDERATIONS

It has established a regular structure that has course will have a use of shopping center,

which consists of 6 levels, with the ceiling of the top floor of any exclusive use.

The main structure resistant to lateral forces on the building will be exclusively built withreinforced concrete, whose characteristic resistance to compression at 28 days is 280

Kg/cm2. It was anticipated that the first level has a height of 5.00mts, being the other

levels of 3.50mts height, in both cases considered from floor to floor.

The government drew up the building with columns and structural walls (plates), and are

defined then a system of structural Walls of concrete; the center of the building does not

have slab, as that will be occupied by metal ladders for access to each floor. The building

will be closing elements which consist of glass panels, so they are not considered to be their

weights during the analysis.

The configuration and arrangement of the structural elements in the plant is shown in Figure

1-1.

Figure 1-1. Plan view of the structural Configuration of the building.

It has been established that the columns will be of bxD = 50x50cm 2, the beams of

bxh = 30x60cm2, the walls of t = 30cm, by the structural configuration in which plant you

have, and the spaces shown are systems of ribbed slabs in one and two directions, whose

thicknesses are 35 cm and 30 cm, with separations from axle to axle of your joists of 40cm.





[6]

2. DEFINING MATERIALS AND STRUCTURAL ELEMENTS

As noted in the previous section, we will work only with reinforced concrete, whose

properties are shown below:

REINFOR ED ON RETE

Name of the Material : f’c = 2 80 Kg/cm2

Specific Weight : ϒ m = 2400 Kg/m3

Resistance to Compression : f’c = 2 80 Kg/cm2

Young’s Modulus : E’c = 252671.328 Kg/cm2

Shear Modulus : Gc = 105279.72 Kg/cm2

Poisson Ratio : 0.2

The Young's modulus of concrete, Ec, is calculated using the expression of section 8.5 of the

ACI 318 2011, where the units in Kg/cm2 are shown below:

= 15100√ ′ [ ]

The shear modulus, Gc is calculated using the following relationship and is determined

automatically by the program.

= 2 + 1 [

]

To create the concrete material in ETABS, follow the path “Define/Material Properties...”

to open the window Material Definition “Define Materials ” in Figure 2-1, then modify theparticular material default that brings the program, 4000Psi, by clicking on the button

.

Figure 2-1. Define command for the creation of the concrete material.





[7]

In the Data window Properties of the Material, “Material Property Data” in Figure 2-2 will

be placed all the information set out at the beginning of this section, then, he will accept all

of the data entered by clicking on the button .

Figure 2-2. Definition of the properties of the concrete Material.

The sections properties to use for our analysis are as shown below:

BE MS

ID : V-30x60

With : 30 cm

Depth : 60 cm

Cover + Stirrup + bar/2 : 5.75 cm

Stiffness to Bending : 0.50E c I g

Stiffness of shear : 0.40E c Aw

Axial Stiffness : 1.0E c A g

COLUMNS

ID : C-50x50

With : 50 cm

Depth : 50 cm

Cover + Stirrup + bar/2 : 4.75 cm








[8]

STRUCTUR L W LLS

(PLATES)ID : Muro 30cm

Thickness : 30 cmCover + Stirrup + bar/2 : 6.06 cm




RIBBED SL BS

(1Direction & 2 Direction)ID : Alig. 1Dir & Alig. 2Dir

Thickness : 35 cm & 30cm

Cover : 2.5 cm

The elements beams and columns are referred to in the ETABS as “Frame Sections...” and,

in order to access this command must follow the path “Define/Section Properties/Frame

Sections...”, as shown in Figure 2-3.

Figure 2-3. Define command for the creation of Frame Elements, Beams and Columns.

Then a window will open that contains a list of the sections by default that brings the

program. To define a new section, which is of the beam and column, we click on the button

on the Figure 2-4, then it will open the window “Frame Property

Shape Type” of the Figure 2-5, then we click on the button





[9]

Figure 2-4. Section names of Beams and Columns by default that brings the ETABS.

Figure 2-5. Type properties of Frame elements.

To define the beam section, you have to enter the above information as shown in

Figure 2-6 and we accept these data by clicking on the button . To define the column

section, we do so in a manner very analogous. Figure 2-7 shows the form as it should of

entered data.





[10]

Figure 2-6. Definition of the beam section.

Figure 2-7. Definition of the Column section.

Then we will define the section of Wall, for which we follow the following path

“Defined/Section Properties/Wall Sections...”, as shown in Figure 2-8. Soon they will open

the window “Wall Properties” and we click on the button and

let such as shown in Figure 2-9.





[11]

Figure 2-8. Route to be followed for the definition of Walls.

Figure 2-9. Definition to Wall Section.

To define the section of slab ribbed, both in 1 and in 2 directions, it followed the route

indicated in Figure 2-10, then, in the window “Slab Properties” select the property of Slab,

Slab1, and then modify it by clicking on . Finally, to define the ribbed

slab in 1 Direction leave the window “Slab Property Data” as shown in Figure 2-11 left and

we accept the data logging by clicking on .





[12]

Figure 2-10. Route to be followed to definition of Ribbed Slabs.

Figure 2-11. Definition to section Slab Ribbed in 1 Direction.

To define the other section Ribbed Slab, this time in 2 Directions, we will do so by clicking

the button , and in the same way you have to enter the information

set as shown in Figure 2-11 on the right. Then we accept all of the entered information by

clicking on all of the windows on the button .





[13]

3. DRAWING OF COLUMNS WALLS BEAMS AND SLABS

After you have defined the materials and all the sections of the structural elements is

appropriate to draw them. The tools for the quick drawing of the different structural

elements are shown in the left part of the screen of the program.

Figure 3-1. Toolbar for quick drawing of structural elements.

We'll start by drawing all the columns in the project, which according to Figure 1-1 van of

the way as indicated in Figure 3-3 is displayed, but not before mentioning that for our

elements are drawn in all the flats we have to use the option of “Similar Stories ” located in

the bottom right that is shown in Figure 3-2.

Figure 3-2. Option of Drawing Similar Stories to draw on all floors.

Quick Draw

commands of

Structural

Elements





[14]

Figure 3-3. Location of Columns.

Then we assign supports embedment perfect at the base of the columns, for this we are

going to the first level using the buttons or also by clicking the button , we

select the base, as shown in Figure 3-4 and then click .

Figure 3-4. Selection of the Plane that we want to be.

Being already in the base of the building, we select the points where they are located in the

columns and go to the Assign command to assign restraints in supports, abutments perfect,

as shown in Figure 3-5. Then we accept this by clicking on .





[15]

Figure 3-5. Allocation of Support Embedment Perfect to the columns.

We now return to the last level in the same way as we arrive to this level; now we'll draw

the walls with the help of the command and we started to draw the walls with just

clicking on the part of the grid where we want to draw the wall. Then, this has to be so, as

shown in Figure 3-6.

Figure 3-6. Location of Walls.

Now, to draw the beams must select the command , to draw the beams in a very similar

way as you did with the walls. Figure 3-7 shows the model with the beams already drawn.





[16]

Figure 3-7. Model of the Building with Beams placed.

The only thing that remains for us to draw are the slabs, we do this by using the command

that has the icon , because it allows us to draw the slabs by means of two opposite points,

as indicated in Figure 3-8.

Figure 3-8. Drawing of Slabs by means of two opposite points.

Finally, the arrangement of the slabs shall be as indicated in Figure 3-9, ready for the

allocation of the loads that will act on the building.





[17]

Figure 3-9. Arrangement of joists of ribbed slabs.

4. CREATION AND ALLOCATION OF LOAD PATTERNS

The next step is the creation of the types of loads that will act on the building that are

defined by Load Patterns, for this we will continue using the Define command, so we will

continue the path “Define/Load Patterns...”, as shown in Figure 4-1.

Figure 4-1. Way to go to Definition of Load patterns.

Then it will open the window “Define Load Patterns” and create new Load patterns for each

type of load that we need for this project. The load patterns that we create are the

following:





[18]

o

Own Weight : Provided and calculated by the program, it will take the name “Own

Weight” and will be “Dead”; not be assigned to load with this pattern.

o

Dead Load : Provided by the weight of elements and materials that are part of

the building, such as lighting, finishes, ceilings, finished floor, internal walls of

subdivision, etc. Your name will be “CM”, and will be of Type “Super Dead”

o Live Floor Load : This is given by the moving components in the building, such as,

desks, tables and chairs, shelves, counters, us, etc. Your name will be “Live” and will

be of Type“Reducible Live”

o Live Roof Load : Generally considered the weight of the people who will be involved

in the placement of the fixtures, finishes, placement of hedges and instruments.

Your name will be “LiveUP” and will be of Type “Live”

Then were created the load patterns according to the type of load as defined above and in

the Figure 4-2 shows the load patterns created.

Figure 4-2. Load patterns created, according to the definition.

Here we can also create a pattern of seismic load that will represent the static shear at the

base of the building and is calculated automatically. To do this we create a loading pattern

of the type “Seismic” called “Sismo X”, which we will represent the static shear in the X

Direction analysis, as well as shows.

Figure 4-3. Load patterns Seismic Static.

What we're missing is to tell the program that the pattern of seismic load that is createdis really oriented to the X-Direction, therefore, we will change this pattern of load by using





[19]

the button that will open the window shown in Figure 4-4, which we

will configure in the manner as indicated. Then we accept everything that is created by using

the button in all windows.

Figure 4-4. Definition of the Pattern of Seismic Load in X Direction.

Once we have created the patterns of load that we need for this project, we proceed to

assign the loads in accordance with the type of load that has. The values for each type of

load are listed in Table 4-1.

After this is performed the assignments of each load to all floors, as appropriate. Their

allocation to each floor is shown in the video.

Type Load Name Value

Super Dead CM 370*

Live Floor Live 500

Live Roof LiveUP 100

Table 4-1. Type Loads and Values

* Its Calculation is shown in the video





[20]

5. WEIGHT SEISMIC EFFECTIVE ACCORDING TO THE NTE E.030

The Weight Seismic Effective of the building is determined in accordance with Article 16.3

of the NTE E.030 that is presented.

As the building will have use of a shopping centre, then, in accordance with Table N°3 of the

NTE E. 030 Design earthquake-resistant, the category of building, which is of Type B. Then,

in accordance with the above, we must use the item a) of Article 16.3.

Such a way of formula, the Weight Seismic Cash of the Building, P, is determined as:

= + +.+.

In ETABS, the way to do this is by using the menu you Define via the command “Mass

Source...”, as shown in Figure 5-1. Then, in the Definition window of Mass Source we enter

the calculated data recently, as well as detailed in Figure 5-2.





[21]

Figure 5-1. Command to calculation of the Weight Seismic Effective.

Figure 5-2. Input Data for the calculation of P.

The results and checks of the calculation of P will be verified at the end of the modeling

and run the analysis.





[22]

6. DESIGN SPECTRUM INCORPORATION

The Design Spectrum incorporation obeys strictly to the application of Article 18.2 in their

item b., which depends on several factors, such as shown in the formula:

=

= is the zone factor, which is found in the Table N°1 of the E.030. For the purposes of

this example, it was assumed that the Building will be constructed in Cajamarca, then:

= .

= is the usage factor, depends on the category of the Building, in this case of Type B, and

in accordance with the Table N°3 previously filed

= .

= it is the factor of soil, which has to do with the study of soils, and according to the local

conditions set forth in the Table N°2, it was assumed for this example a soil type S3,

therefore,

= . = is the coefficient of reduction of seismic force, which depends on the structural system

and the predominant material. As the greater part of the system is composed by walls, it

will start the analysis by considering that it is a system of Structural Walls, then,

=





[23]

= is the seismic amplification factor, which depends on the period of the Structure and

the Soil. As this value depends on a period of time T(s) and, the Design Spectrum is plotted

as a function of the time, then, you can generate a Table of Values of Sa/g - Time with Sa/g

dependent on C, then the Design Spectrum would be graphed as shown in Figure 6-1, for the

factors determined above:

Figure 6-1. Design Spectrum, according to NTE E.030.

To enter this spectrum to the ETABS we must follow the following steps:

1.

Copy the columns of T and ZUCS/R in such a way that they are together, as shown

2. Copy and paste this table into a notepad, and save the file.

category : B Z = 0.4

Zone : 3 U = 1.3

Soil Type : S3 S = 1.4

Structural System : T p = 0.9

building : Regular R = 6

T C ZUCS/R

0 2.5 0.30333333

0.2 2.5 0.30333333

0.4 2.5 0.30333333

0.6 2.5 0.30333333

0.8 2.5 0.30333333

1 2.25 0.273

1 .4 1 .6 07 14 28 6 0 .1 95

1.8 1.25 0.15166667

2.2 1.02272727 0.12409091

2 .6 0 .8 65 38 46 2 0 .1 05

3 0.75 0.091

3 .5 0 .6 42 85 71 4 0 .0 78

4 0.5625 0.06825

4.5 0.5 0.06066667

5 0.45 0.0546

6 0.375 0.0455

7 0.32142857 0.039

8 0.28125 0.034125

9 0.25 0.03033333

10 0.225 0.0273

Reinforced Concrete, of Structural Walls

DESIGN SPECTRUM - NTE E.030

0

0.04

0.08

0.12

0.16

0.2

0.24

0.28

0.32

0 2 4 6 8 10

S a / g

Periodo, T(s)

T ZUCS/R

0 0.30333333

0.2 0.30333333

0.4 0.30333333

0.6 0.30333333

0.8 0.30333333

1 0.273

1.4 0.195

1.8 0.15166667

2.2 0.12409091

2.6 0.105

3 0.091

3.5 0.078

4 0.06825

4.5 0.06066667

5 0.0546

6 0.0455

7 0.039

8 0.034125

9 0.03033333

10 0.0273





[24]

3.

In the ETABS, follow the path indicated in Figure 6-2, then, in the window that

opens, where it says ASCE7-10 deploy and look for the option that says “From File”,

as well as in Figure 6-3 to have the option to import the spectrum from the previously

saved file.

Figure 6-2. Path to import the Design Spectrum.

Figure 6-3. Selection of from file command to import the Design Spectrum.





[25]

4.

Then we click on the button , and in the window of the spectrum

we load the file in .txt format by clicking on the button and load the file

format *.txt as shown in Figure 6-4, giving finally click on the button .

Figure 6-4. File in notepad to be imported into ETABS.

5. Finally, we will see the graph of the Design Spectrum that has been imported into

program, which is to be displayed as shown in Figure 6-5. Then we accept all byclicking on .

Figure 6-5. Graphical display of Design Spectrum imported.





[26]

7. AUTOMATIC CALCULATION OF SHEAR STATIC AT THE BASE

To determine the Shear static at the Base, V, of the Building, we have to resort to the

expression shown in the Article 17.3 below:

= ∙

The description, location and values for each parameter are indicated in section 6 of

this text. In addition to this expression, the NTE E.030 indicates to us that the

expression:

≥ 0.125

The correct way to determine the Shear at the Base of the Building is the following:

1°.

Determine the Fundamental Period, T, of building.

In the program we can see the fundamental period, T, of the building using the Table “Modal

Participating Mass Ratios”, whose capture is shown in Figure 7-1.

Figure 7-1. Modal shapes, display of the Table of PPMM and Fundamental periods.

2°.

Calculate the value of Seismic Amplification Factor, C, in accordance with

the type of soil, using the expression of Article 7 of the E.030..

= 2.5 ( ) , ≤ 2.5

= 2.5 (

0.9

0.355) = 6.33802817 > 2.5∴ = .





[27]

3°.

Assess the value of /.

= 2.5

6 = 0.416667 ≥ 0.125

4°.

Determine the value of

= 0.41.31.40.416667

= 0.30333333

In the program, this data is entered in the window “Define Load Patterns ” (Figure 4-3),

entering the value calculated in Base Shear Coefficient , C , as shown in Figure 4-4.

5°. Calculate the Shear at the Base.

Making use of the expression indicated at the beginning of this section, we calculate the

Shear at the Base of the Building, but we first need to calculate the weight effective

seismic, which in the program is displayed using the Table “Center of Mass and Rigidity”

whose capture is shown in Figure 7-2.

Figure 7-2. Weights Seismic Effective of the Building.

Here we can see the weights seismic effective concentrated in the center of mass,

calculated for each floor and, due to which we assign a single diaphragm for all levels, in the

column of weights accumulated, we see the sum of the weights accumulated that come to

each floor, with the value of the Weight Seismic Cash of the Building equal to =

3 670 272 = 3 670.272 . Then, the shear at the Base of the Building will be: = . × . = . .





[28]

8. CALCULATION OF DYNAMIC SHEAR

To determine the Dynamic Shear, product of the spectral acceleration and her modal

shapes, applying combinations of modal and directional CQC and ABS. We follow the path

shown in Figure 8-1 and then will be opens the window, “Load Cases” where we can see t heload cases that we have generated, product of the loading patterns as defined in Item 4.

Figure 8-1. Path to Command Load Cases.

In this window we will generate the cases of Dynamic load-Type Response Spectrum, for

each direction of Analysis, whose definitions are shown in Figures 8-2 and 8-3.

Figure 8-2. Definition of the Case of Dynamic Load in the X Direction, EQ-XX.





[29]

Figure 8-3. Definition of the Case of Dynamic Load in the Y Direction, EQ-YY.

Then, we accept every case load generated by the button , leaving the load cases

Static and Dynamic, as shown in Figure 8-4. After this, we ran the model and proceeded to

view the sharp Dynamic for Each Direction.

Figure 8-4. Load cases Static and Dynamic.

After having performed the analysis, it comes with the display of the Dynamic Shear using

Tables, being that we will use for this Table “Story Forces” as shown in Figure 8-5. Here we

can see the values for the Shear Dynamic in the Directions X and Y.





Figure 8-5. Display through Tables of the Dynamics Shear in the Directions of X And Y,

Vx = Vy = 859.777 Tn.

Figure 8-6. Graphical display of the Dynamic Shear on all floors.

manual of static and dinamic analysis 2014

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