design project1

CIV 6271 Design Project Group1

CONTENT1. Executive Summary.............................................................................................................2

2. Conceptual Design...............................................................................................................5

2.1 Scheme Steel structure.............................................................................................5

2.2 Scheme 2 Flat Slab Concrete Structure.....................................................................7

3. Structural Design...............................................................................................................10

3.1 Slimdek Level 5......................................................................................................10

3.2 Level 1 Primary Beam..............................................................................................12

3.3 Column....................................................................................................................13

3.4 Truss........................................................................................................................16

4. Detailing............................................................................................................................21

4.1 The connection for ASB to ASB................................................................................21

4.2 Beam to column connection....................................................................................22

4.3 Roof to column connection.....................................................................................24

4.4 Column to foundation connection...........................................................................25

5. Foundation........................................................................................................................27

6. Method statement............................................................................................................28

6.1 Slimdek....................................................................................................................29

6.2 Method for the safety during the construction.......................................................30

7. Letter to Client..................................................................................................................31

Reference..............................................................................................................................32

Appendix...............................................................................................................................33

1


1. Executive Summary

This project involves a 5-story laboratory building with a full-height atrium. The

building is located at the centre of a city, beside an existing highway and over an

existing 5.0m wide and 2.0m canal. The construction site is bounded in a size of

30x29m. It consists of two blocks with equal sizes on each side of the canal, shown

in Fig.1.1. Block adjacent to highway will be used as an office building with seminar

rooms on the ground floor (level 1). The other block is mainly for laboratories. Level

5 of both blocks is to be used for plant. The overall height of the building is 21m

excluding the height of atrium, where level 1 is 5m high and the rest are 4m.

The client’s requirements are addressed, as followed:

In the office building, internal columns are not permitted in level 1 seminar rooms.

External columns are not permitted within 2m of the edge of the existing highway

between level 1 and 2. Internal columns on the rest levels must be at least 5m from

the external building line;

Minimum clear headroom of 2.8m must be ensured. Besides, a 0.7m deep service

zone is to be provide beneath the 2, 3,4 and 5 floors;

There must be a 2m wide circulation balcony at levels 2, 3 and 4, and also two

combined stair well/lift/elevator shaft cores are to be provided;

Except the atrium roof, all other roof area is flat and need no t be glazed. All external

walls are to be clad in masonry.

1m thick impermeable clay lining along the canal must not be damaged during

construction. And traffic on the highway must not be interrupted.

The building is to be built on a layer of soft clay with flat surface, beneath which is a

rock layer with allowable bearing pressure of2500kN /m2. Ground investigation

shows no ground water in the soil.

2


Figure 1.1 General layout of the building

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2. Conceptual Design

At this stage, two schemes were proposed and then evaluated by a few criteria, such

like, feasibility of structure, cost, sustainability, etc. The first construction scheme is

a steel framed building which adopts Slimdek floor system, while the second scheme

is a pure concrete framed building with flat slab floor. Size of structural members is

preliminarily determined by rough calculations.

2.1 Scheme Steel structure

Considerations for choosing proper layout according to client’s requirements can be

concluded as: (1) a different load transfer between level 1 and 2, i.e., the row of

column adjacent to the highway on level 2 is supported by beam; (2) a limited height

for floor system; (3) large loading on the top floor causing big deflection; (4)

vibration of the floor should be limited; (5) lack of space for foundation along the

canal and beside the highway.

Figure2.1 Scheme 1 Column Layout

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Column layout for the first scheme is shown in Fig 2.1. For the purpose of efficient

construction, a regular shape of grid lines was chosen. The bay size was kept to

5x6m, and columns were set on the corners of the bay, except for the columns

supporting circulation balcony. Primary beam spans 5m and Secondary beam spans

6m at 2.5m spacing. In this configuration, load is transferred in a sequence of slab,

secondary beam, primary beam, column and foundation. A special situation is on

level 1, where columns near the highway were shifted 2m back to meet the client

requirement. In this case, load of the edge columns on level 2 is transferred to

primary beam, then columns on level 1 and foundation in the end.

All columns and beams were braced by the lift cores in the middle to resist lateral

shear and torsion under wind loading. Cores are 6m in length and 4m in width, built

in reinforced concrete.

Scheme 1 is also featured with the use of Slimdek. Slimdek is a flooring system

formed with ComFlor 225 deep decking spanning between Asymmetric Slimflor

Beams (ASBs), shown in Fig. 2.2. Practical evidences show that, it is cost-effective,

and easy and fast to build. But the main reason to choose this flooring system is that

it can greatly reduce the overall depth of slab, so it is favourable to the client’s

requirement.

Figure2.2 Slimdek

With the proposed solution, preliminary sizing of some structural elements were

determined, which are listed below.

Slab and secondary beams: Slimdek (C30 lightweight concrete, ComFlor 225

steel decking, 280ASB100)

Primary beam: UB457x191x67

Primary beam on level 1: UB 914X305X253

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Column on level 1: UC356X406X340

Pile foundation with eccentric column is to use to avoid disturbance to the canal and

the highway. Because the soil is very soft (soft clay), piles must be driven to the rock

layer to gain enough bearing resistance to the building.

2.2 Scheme 2 Flat Slab Concrete Structure

2.2.1 Structural type and layout

Flat slab are ideally suited to fast and economic multi-storey construction. The

absence of beams allows storey heights and flexibility of both partition location and

horizontal service distribution. It is easy to seal partitions for airtightness, acoustic

isolation and fire containment. It is also suitable for structures like hospitals and

laboratories accommodate sensitive equipment. Punching shear and deflections are

generally critical but edge beams to support cladding are unnecessary. Slabs are

assumed to be supported only by columns. The seminar room part (left ground floor)

of the building is designed as normal concrete frame structure and Flat slab structure

is adopted in other parts of the building. As there are no beams carrying any loads,

Lateral stability will be provided by the edge beams which are designed into the edge

of the slabs and can transfer loads to lift shaft wall.

2.2.2 Preliminary sizing of the main elements

2.2.2.1 Size of the beams (only seminar rooms)

height of the beam h=(1/8~1/12)span, width b=(1/2~1/3)h. Maximum span: 8 meter

Primary concrete beams: 1200mm×400mm

Secondary concrete beams: 600mm×300mm

2.2.2.2 Size of the columns

All the loads on the left side of the structure is designed to be transferred to the

primary beam and then the column. This column could be very critical.

Columns: 600mm×600mm

2.2.2.3 Thickness of concrete slabs

As flat slab is adopted, the thickness of slab can be reduced to less than 260mm

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compared with normal slab with a large thickness.

Level 1-4: 220mm

Level 5: 260mm

Roof: 210mm

Figure2.3 Layout of ground floor

2.2.3 Load transfer paths

For the left part of the building, load on slabs will be

transferred to columns, then to the critical beam and two

columns of ground floor and finally to the foundation. (As

shown in the right figure)

For the right part of the building, load on the slab is designed

to be directly transferred to the columns and then to the

foundation.

Figure2.5 Load transfer path

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2.2.4 Method of construction

Grade C40 in-situ concrete is used in this scheme and the canal would be used for

material transportation.

2.2.5 Feasibility statement

As there is an existing canal beneath the structure, more attention should be paid

during the construction of the foundation. More money and labour would be

consumed by this concrete flat slab structure as it needs extra area for foundation.

2.3 Scheme Evaluation

Table1 Scheme evaluation

Scheme 1 (Steel framed) Scheme 2 (Concrete flat

slab)

Advantages • More environmentally

friendly.

• Easy fabrication, less

labour cost

• Light weight concrete

provides good sound

insulation between floors

• Recyclable and reusable

• No beam in level 2~5

• Easy fabrication,

comparing to

traditional concrete

framed structure

• Good ability to

withstand corrosion

• Good fire resistance.

Disadvantages • Low heat resistance

• Rusting easily

• High material cost

• Need extra area in

foundation

• CO2 emission

• Need a large supply

of manpower

• Not easy to examine

and repair in service

phase

8


The building is located in the city centre. Therefore, in addition to the factors like

cost and sustainability, it is essential to shorten the construction duration to reduce

the impact to communities nearby. In accordance with the finding, scheme 1 was

chosen as the final scheme.

3. Structural Design

Slimdek was designed with the aid of a computer programme, which is available

from Corus Ltd. Structural elements other than slab were model in SAP2000 to find

the optimized solutions. All the joints were modelled according to the real. Critical

elements were checked by hand calculations, which will be presented in the

following sections.

Design loadings

Atrium roof: 1.0kN/m2

Flat roofs: 1.5 kN/m2

Plant areas: 7.5 kN/m2

All other floors and balconies: 5.0 kN/m2

3.1 Slimdek Level 5

Design of internal beam using 300ASB 153 sections

9

300ASB153

5000

300ASB 153

300ASB 153


300ASB153 were used in this slab and the steel grade is S355. For the concrete light

weight concrete

Concrete density: 1900Kg/m3

Deep decking: SD225

Load type: Uniformly distributed load

Slab weight total: 2.72 KN/m2; Beam weight: 152.8 X 6 X 9.81/103=9.0 KN

Applied Moment: Slab (including the deck): 2.98 KN/m2; Steel beam: 0.3 KN/m2

Total: dead load: 3.19 X1.35=4.306 KN

Imposed load: 7.5X1.5=11.25KN

Total load: W=15.42X6X5=466.86KN

Mx=466.86X6/8= 350.15KN

Moment resistant: Mc (assume the plastic neutral axis lies in the steel web and below

the solid concrete slab)

The moment resistance of the concrete slab:

Rc =0.45f cu¿

¿BeDs ; Ds=316-225=91mm ; Be=6000/8=750mm;f cu¿

¿=30N/mm2

The longitudinal force due to the shear bond action between the steel section and

concrete Fsb is given by Fsb= f sbLP/4, where band perimeter. P=2(b t+t t+d)-tw

P=2 X(190+24+262)-27=921mm

f sb = 0.6x6000x921/400=828.9KN

Since f sb< Rc, Hence: partial share connection

To determine the position of the plastic neutral axis: Rt=Bt*Tt*Py=1573.2K

R=Bb*Tb*PY==2484KN

Rs=As* Py==6742KN

Rw=2704.8KN

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Take Rc= Fsb=828.9KN;

Rt+Rc =1573.8+828.9KN

Rt+Rc=2402.7KN;

Rb+Rw*(d-2(Ds-Dc-7t)/d) =2484+2704x (262-2x (61-30-24))/262=5044KN

3.1.2 Bending resistance check

Max applied moment = 350.15kNm /m

Moment resistance, Mc = 872.8 kNm /m

So moment resistance is satisfactory

3.1.3 Deflection check

Allowable deflection ðmax , is the smaller of 1) Effective span/200 and 2) 20.0 mm

(absolute maximum value), and 3) Slab depth/10 = (31.6mm )

The deflection subjected to the imposed load: 7.68mm < L/360

Hence safisfactory

As the deflection is less than span/200, the beam is considered to be satisfactory for

total deflection.

3.2 Level 1 Primary Beam

MEd = 2635.8 KNm

Section selection:

Assuming section belongs to class 1.

M b , Rd=X¿×W pl, y ×f y

r M 1

Using Mb, Rd=REd and XLT=0.79,

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W pl , y=M Ed ×r M 1

X¿× f y

=2635.8 ×106×1355

=7424.8cm3

Try UB 383x292x194, the cross-section belongs to Class 1.

Check the resistance of cross-section:

Bending:

M c , y , Rd=W pl , y ×f y

rM 1

=7650× 106 ×3551

=2712 KNm>M Ed=2653 KNmOK !

The lateral restrain will be provided by adjacent slabs, no torsion buckling needs to

be considered.

Shear:

VEd = 2461.6KN

Shear resistance isV pl , Rd=AV

f y /√3r M 0

, where AV =A−2b t f +(tw+2r ¿ t f =11710mm2

Therefore, Vpl,Rd= 2533.8KN¿ 2461.6KN OK!

hw

tw

=797.374.7

=54.2<72×εη=58.6

Therefore, no shear buckling check required.

3.3 Column

Ground Floor Column

The column is assumed to be pinned by both ends.

, , , is very small, so neglected.

Try UC 356x368x202, S355.

Section properties:

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, , , , ,

, , , , ,

, , ,

For flanges

,

For web

,

, , ClassΙ.

Shear buckling check , OK.

Axial force

Major axis

Minor axis

Reduce bending moment resistance

13


No moment in minor axis, hence check is not needed.

Shear force

, shear neglect.

Buckling resistance in compression

, and grade S355.

y-y axis buckling curve b

z-z axis buckling curve b

Buckling curve: major (y-y) axis

Buckling curve: miner (z-z) axis

OK.

Buckling resistance in bending

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Imperfection factor, α ¿=0.21

∅ ¿=0.5 [1+α¿ ( λ¿−0.2 )+λ¿2 ]=0.5 × [1+0.21× (0.339−0.2 )+0.3392 ]=0.572

X ¿=1/¿¿

Mb , Rd=¿ X ¿W y f y/ γ M 1=0.97× 3972×103 × 355

1=1368 KN . m>M y,Ed ¿

Therefore, buckling resistance in buckling is ok!

Buckling resistance combining bending and axial force

Cmy=¿ 0.6+ 0.4× (−0.5 )=0.4¿

CmLT=¿ 0.6+0.4 × (−0.5 )=0.4 ¿

k yy=Cmy (1+( λ y−0.2 )N Ed

x y NRk / γ M1)=0.424

k zy¿Cmy(1−0.1 λz

(CmLT−0.25)NEd

x z N Rk /γ M 1)=0.837

NEd

x y N Rk /γ M 1

+k yy

M y , Ed

X¿ M y , Rk /γ M 1

=0.383<1

NEd

x y N Rk /γ M 1

+k zy

M y , Ed

X¿ M y , Rk /γ M 1

=0.5<1

Therefore, buckling resistance in bending and axial compression satisfied.

3.4 Truss

Roof truss (Fink truss)

The truss to be designed is to support a roof which is only accessible for routine maintenance. The truss is 9m span with 24° pitch. The dimensions of the truss are shown in the figure below. The truss uses hollow sections for its tension chords,

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rafters and internal members. The truss is fully welded. Truss analysis is carried out by placing concentrated loads at the joints of the truss. All of the joints are assumed to be pinned in the analysis and therefore only axial forces are carried by members.

Figure3.2 Front elevation of fink roof

Characteristic actions

Permanent actions

Self-weight of roof construction 0.75kN/m2

Self-weight of services 0.15kN/m2

Total permanent actions 0.90kN/m2

Variable actions

Imposed roof actions 1.0kN/m2

Total imposed actions 1.0kN/m2

Ultimate Limit State (ULS)

Partial factor for permanent actions

Partial factor for variable actions

Reduction factor

Design value of combined actions

Design value of combined actions on purlins supported by truss

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For distance of 2.25m between purlins center to center

Design value

Design value of combined actions on truss

For a purlin span of 6m

Truss analysis (due to forces Fd)

Reaction force at support A

Table2 Load of each element

FAB 138kN CompressionFAC 126kN TensionFBC 34kN CompressionFBD 123kN CompressionFCD 42kN TensionFCE 84kN Tension

Partial factor for resistance

, ,

Design of Top Chords (members AB, BD, DF, FG)

Maximum design force (member AB and FG) =138kN (Compression)

Try square hollow section in S355 steel

Material properties:

Modulus of elasticity E=210000N/mm2

Steel grade S355 and thickness≤40mm

Yield strength fy = 355N/mm2

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Section properties:

Depth and width of section h, b=80mm

Thickness t= 5mm

Radius of gyration iz= 30.5mm

Area A= 1470mm2

Classification of the cross-section

Class 3 limit=

13<34, so the section is at least class 3.

Compression resistance of the cross-section:

OK

Therefore, the compression design resistance is adequate.

Flexural buckling resistance:

Determine the non-dimensional slenderness for flexural buckling:

Determine the reduction factor due to buckling

OK

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Therefore, the design flexural buckling resistance of the selected SHS is satisfactory.

Design of bottom chords (members AC, CE, EG)

Maximum design force (members AC and EG) =126kN (in tension)

The bottom chords will also be a SHS, S355. By inspection, the design tension resistance is equal to design plastic resistance of the cross-section.

OK

Design of internal members (members BC, CD, DE, EF)

Maximum design compression force (BC and EF) =34kN

Maximum design tension force (CD and DE) =42kN

Maximum length in compression is BC and EF =1096mm

Try a SHS, in S355 steel.

Following the same design process as above, the following resistance can be calculated:

Flexural buckling resistance (Lcr=1096mm), Nb,Rd=155kN

Tension resistance Npl,Rd=239kN

Thus all internal members will be selected as SHS, in S355 steel.

Serviceability Limit State (SLS)

Partial factor for permanent actions

Partial factor for variable actions

Design value of combined actions

Design value of combined actions on truss

Deflection:

The maximum allowable deflection is assumed to be span/300

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The maximum deflection of the truss is obtained for the SLS value of combined actions (i.e. Fd=37.4kN). The deflection at the apex was found to 13.8mm when all of the joints are assumed to be pinned. Deflection is therefore satisfactory.

4. Detailing

4.1 The connection for ASB to ASB

The connection for the ASB to ASB is determined depending on the British standard

and the end plate connection was recommended to be used.

The end plate may be taken as a standard width of 200mm for all ASB sections,

which allows connections to 203 UKC and larger columns. The vertical distance

between the bolts is 75mm for 3-bolt rows and it also recommended that for the span

<6m, the end plate thickness for moment resistant connections should be 12mm. The

table below also advertised to use M20 Grade 8.8 Bolt for the connection.

There are also some detailing rules for end plate connection to ASBS. The data is

shown as follow.

20

Figure4.1 Recommended bolt sizes and plate thickness for ASB connection


From the data provide from the slimdek manual, all the data for the ASBS

connection can be obtained as below.

Bolt: Grade 8.8 M20

Plate thickness: 12mm

The spacing of the bolts: 75mm

Dimension for B in the figure above

The moment resistant is 192KN.M

The web panel share force is 781KN.M

4.2 Beam to column connection

Med=211KN.m, Ved=106.5KN.m

Connection structural elements

Cantilever under balcony: UKB 457x191x82

Column: UKC 356x368x129

Design grade 43 M20 8.8 Bolts 200x20 END PLATE

A mini haunch 150mm deep will develop a moment of 351KN

Table3 Moment calculation

Row No Beam

side

Column

side

Minimum Lever

arm

Moment

capacity

Cumulative

moment

capacity

1 274 266 266 0.542 144.172

2 228 266 228 0.452 103.056 247.228

3 182 230 182 0.362 65.884 313.112

4 136 211 136 0.272 36.992 350.104

21

Figure4.2 Detailing rules for end plate connections to ASBs


Total 812 350.104

The moment capacity for 2 rows will suffice check compression.

Compressive force or column is 812KN for 4 rows bolts efficient is 812KN for 2

rows of bolts. Compressive force on column is 494KN, adequate, hence using 2 rows

bolts. Vertical shear check; Applied shear is 106.5KN.m

Bottom row dedicated to share provides 2x91.9=183.8KN

Each tension row connection resistance=331KN > 106.5KN.m Hence ok!

Web panel share check

The unstiffened web panel shear resistance is 605KN

The applied web panel shear by two rows of bolts is 494KN. Hence ok!

Wels to end check

The unstiffened web panel shear resistance is 605KN

The applied web panel shear by two rows bolts is 494KN

Wels to end plate.

Provide: Tension flange: 12Fw, Web 8Fw, Compression Flange: 8Fw

Haunch:

Angle of flange is taken of 60 degrees.

Fillet weld with a length equal to the flange thickness.

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4.3 Roof to column connection

Flexible end plate – Beam to UC column

Figure4.3 Front elevation of connection of bottom chord to UC column

Figure4.4 Plan view of connection of bottom chord to UC column

Design information:

Bolts: M16 8.8

End Plates: 200x90x10

Welds: 6mm fillet

Material: All S355 steel

Tie force=126kN< 215kN

The beam side of the connection is adequate.23


4.4 Column to foundation connection

Column to foundation connection

Connected structural elements Figure4.5 Actions on column footing

Column level1 UKC 366x368x202 taken from dead loading

Primary sizing:

650x450x50 base plate with four M24, Class 8.8 bolts each side.

The foundation is to be in C30 concrete.

Check whether there is no tension in the bolts.

Distance to edge of compressive stress block.

Compression , OK.

And there is no tension in the bolts.

and .

T shape stress block

24


Required design stress

586kN, 157kN﹒m combine.

Check whether there is no tension in the bolts.

Distance to edge of compressive stresses block

Compression

No tension in bolts.

Base plate thickness

The required plate thickness is the larger value resulting from (a) or (b) below:

(a) Compression side bending

(b) Tension side bending

where T=0, hence

Therefore,

Use 45mm plate.

Holding down bolts and anchorage

Use two M24, Class 8.8 bolts, but no tension in the bolts. (Bolt spacing=300mm)

25


The overall embedment depth in the concrete (Excluding the grout beneath the base

plate) is 450mm (min requirement)

Shear Transfer to concrete

Check if the horizontal shear is transferred by friction.

Available shear resistance , OK.

Welds: 10mm fillet weld both sides of the web.

5. FoundationThe site is located at the city centre and the site condition is shown as below

Table4 Site conditions

Description Depths Soil data

Sand and Clay Ground level - 16.0 m C = 40 kN/m2

Rock Below 16.0 m Allowable bearing

pressure =

2500 kN/m2

The max load which transferred for the column to the foundation is 2400KN for the

corner column of the building and if the pile designed as friction pile the allowable

pile bearing load is not enough to bearing the column load. In terms of this situation,

the end bearing pile with a diameter of 600mm and depth of 16m should be used

under this building. In this case, allowable pile bearing load is 2600KN, so it

designed as single pile for each column is enough to carry the load from upper

structure. Addition to that, the building is constructed nearby an existing highway

and over an existing 5.0m wide x 2.0m deep canal. So during the construction of the

foundation, the 1.0m thick impermeable clay lining must not be damaged during

construction of the foundation and this process also should not influence use of the

existing highway. In consideration of that, bored and cast-in-place pile can be used in

this case in order to minimise the impact to nearby cannel and highway. Besides

that, the pile which located along the canal should be eccentric and make sure there

26


no adverse effect on the waterproof layer during the building’s construction and

using.

The figure above demonstrated the main construction process of the cast-in-place

pile. It is clear that during the construction process, the pile hole is achieved by

drilling in to the soil rather than hammering into the soil, therefore it makes little

vibration and compaction effect during the construction process and protect the

waterproof layer and highway from damaging.

27

Figure5.1 Construction process of cast-in-place pile


6. Method statement

Generally, it will take 80 to 100 days from the beginning of excavate and construct

of the foundation to the end of the clear site. The typical progress schedule (in days)

is shown as above. After the construction of the foundation finished, several works

would be undertook in parallel and significant on-site time could be saved. Besides

that, by manufacturing the frame in the factory can also reduce the risk of delay

caused by bad weather or insufficient or inadequate construction resources in the

locality of the site.

6.1 Slimdek

Some typical for the installation method of the decking should be noticed and the

graph below shows that the connection of the decking and the ASBS.

28

Figure6.1 The progress schedule of the construction work


The diaphragms are fixed to the edges of the lower flanges of the beams on both

sides (except for edge beam situations) using two fixings at pre-marked positions for

each length. The 1800 length equates to three sections of ComFlor 225 decking. Each

length should be positioned and abutted accurately so that the 600mm pitch of

decking sections is located as shown on the layout drawings.

After the decking is placed, props should be positioned and it also should not be

removed until the concrete has achieved 75% of its specified strength (normally 7

days).

A temporary bridge should be built on the cannel during the construction in order to

make the construction work convenience and easy to convey materials across the

canal.

6.2 Method for the safety during the construction

1. A protection shutter should be laying 1m away aside the cannel to protect the

canal and the waterproof layer from damaging during the construction process.

29

Figure6.2 fixing of end diaphragms at ASB

Figure6.3 Propping during the construction


2. Protection net also should be provided along the edge of each floor to minimise

the risk of the falling materials from the upper floors.

3. Scaffold cannot be removed until the construction process all completed and it

should also provide enough stability for works to stand and walk. The construction

workers should educated about the adequate construction method before they start

their work and some safety criterion should be observed by the worker and engineer.

30


7. Letter to ClientDear Customer,

Having considered experimental equipment will be accommodated in the laboratories

of the building, in the initial stage of slab design, the structure is designed to has high

frequency floors (freq.≥10 Hz). (in accordance with Appendix G of Vibration

serviceability of post-tensioned concrete floors provided by University of Sheffield)

Generally speaking, equipment could be installed in the laboratories and it is

suggested to set this equipment in the area near lift shaft core which has a relative

high stiffness which means the effects of vibration could be minimised. Also, lateral

embrace of the whole structure is provided by the lift shaft core.

Further vibration investigation could be carried out by using finite element method

and modal shape of the slab is expected to be analysed. For each nodal points of n th

mode, the equipments are advised to be set on as the deflection and acceleration

would be the minimum, which indicates the impacts on equipments are relative

smaller. Normally, the critical nodal point of 1st mode of the slab is on the midpoint

of span.

Sincerely yours,

Group 1

31


Reference

BCSA SCI. (2009). Joints in Steel Construction - Simple Connections.

Ltd.Corus. (2009). Slimdek Mannual.

OwensW.Graham. (1994). Steel Designer's Mannual. Blackwell.

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Appendix

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design project1

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