Structural Design for Low Rise Building

7/28/2019 Structural Design for Low Rise Building

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Supervised by : Dr. Khaled El-Sawy

ID#Name200303838Saeed Mohammad Al Kaabi

200304178Ahmed Obaid Al Dhaheri

200303853Mohammad Owais AL Daraei

200303840Ahmed Abdullah Al Braiki

United Arab Emirates University

College of Engineering

Department of Civil and Environmental Engineering

Industrial Training & Graduation Projects


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-Introduction

-Structural design of :

o Slabs

o Beams

o Stairs

o Columns

o Tie-beams

o Footing

-Environmental, Financial, and Social Impact

-Conclusion


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.fc` Compressive strength of concrete = 28MPa

.fy Yielding strength of steel = 420 MPa

.Ig Moment of inertia

.Ag Area gross

.Ie Effective moment of inertia

.wu Ultimate weight

.Vu Ultimate shear

.Mu Ultimate bending moment

.Mcr Cracking moment .Icr Cracking moment of inertia

.K Effective length factor

.Ec Elasticity of concrete


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The considered low-rise building consists of three blocks

The Majles and Kitchen were designed in GP-I

The Villa is designed in GP-II

The slabs, beams, columns, tie- beams, stairs and footings arestructurally designed.

This structural design in project followed the ACI-318-02M code.

Prokon, AutoCAD and Excel sheets are used in the design.


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Project area = 903 m2

Each floor area of villa

Ground floor = 338 m2

First floor = 261 m2

Each floor consist of several bedrooms, sitting rooms,family hall

Kitchen in ground floor


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What is structural design?

It is finding concrete dimensions and reinforcing steel areas of eachstructural element with insurance of safety and serviceability of themember.

Before designing :

Type of the structural element (i.e., beam, column etc)

The loads carried by the member

The architectural limitations on the member dimensions


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Figure 2:

Architectural plan for first floor.

Figure 1:

Architectural plan for ground floor.


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Figure 3:Typical structural elements


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it is one way

blocks and solid part for R1:

5.3m

5.2m2

short

long

L

L

0.3m

0.43m

nb=22

nr=7

Width of Rib 0.2m

Width of Block 0.38m

No. of Ribs nr 7

No. of Blocks along Ls nb 22

Width of Solid part S1 0.43m

Width of Solid part along Ls (S2) 0.3m

L 5.3m

Ls 5.2m


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m

kN

8.1040.58)1.7(21.4(4.28)1.7(L.L)1.4(D.L)w u

Load Calculation160 160 160420 420

380200380200

Block

Rib

30060

Dimensions in mm

cover)(floorblock)of(weightrib)of(weightslab)topof(weightD.L

m

kN4.380.58)(20.2)(525)10.3

2

0.20.16(25)10.58(0.06D.L

Figure 4: Drawing for ribbed slab (R1)


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Figure 5: Binding moment diagram for R1

Bending Moment for Simply Supported Rib R1

Length (m)

Bending moment

(kN.mm)


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Figure 6: Required steel area for R1

Area of steel is 252mm2 (2#13)

Steel Area R1

Length (m)

Steel Area

(mm2

)


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Shear design for R1

Length (m)

Shear Force

(kN.mm)Figure 7: Shear diagram for R1


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From PROKON software (Vu = 21.1 kn)

stirrupsneed2

VV

20.24KN,2

0.85x47.6

2

V

c

u

c

22.78kN0.85

0.85(47.6)21.1

VVV cus

mmV

dfAS

s

yv450434

22780

3004205.78

Swcs VkNdbfV 4.190300180283

2

3

2max,

kN6.74300180286

1dbf

6

1V wcc


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From PROKON software (Vu = 21.1 kN)

#10@150mmchoose

150mmS

994mm180

3x2x71x420

b

f3A

150mm0.5(300)0.5d

600mm

ofsmallestSmax

w

yv

max

95.25kN30018028

3

1dbf

3

1V

wcs

22.78kNVs

mmS 450


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2#13

2#10

#10@150mm

Check Deflection for R1 Simply supported beam

Minimum thickness of R1 = L/16 = 5.2/16=0.325 m

The actual thickness of R1= 0.36 m > 0.325

It is acceptable

Steel Arrangement

Figure 6:

Final drawing for ribbed slab (R1)


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77.112kN/m8.261.745.051.41.7W1.4WW

8.26kN/mW

45.05kN/m10.53328.55

WWO.Wreaction)(fromWW

kN/m.10.53.53h3kN/mW

3kN/m250.3(0.2x2)W

kN/m.30.20.625bh O.W

8.26kN/m0.58

2.722.07

0.58

Rreaction)rib(fromW

28.55kN/m0.58

7.159.41

0.58

Rreaction)rib(fromW

LDu

L.L

D(wall)partsolidbeamDD.Total

2

D.L(Wall)

partSoild

beam

L.L

L.L

D.LD.L

Beam : DB5

20cm

350cm

Solidpart Solidpart

20cm

20cm

20cm

Beam 30cm

30cm

Wall


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Steel arrangement

Figure 7: Drawing of DB5


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Figure 8: The stair design.

Slope of the stairs

1

28.98380

210tan

Length of the stair

Thickness to control deflection

4.342m=1.23.8=L 22

mmmmL

h 300272

20

11004342

20

min


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Load calculation for the stair

2.8kN/m1.42w

/1.165.108.28.2w

/8.24.12w

/8.22508.04.1w

/5.10253.04.1o.w

Liveload

LD.

coverfloor

step

slab

total

mkN

mkN

mkNhb

mkNhb

stair

beam

mkNLLw

mkNLDw

/8.2.

/4.18cos

1.16.

2

1


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Length (m)

Bending moment

(kN.mm)

Length (m)

Area of steel (mm2)


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From Prokon As=1270mm2 should be between As, min and As,max

Asmin = 0.0033*1400*230=1062.6 mm2

As,max = 0.02125*1400*230=6842.5 mm2 , Asmin < As< Asmax so we will use 7 bars diameter 16

0.02125420600

600

420

280.850.850.75

f600

600

f

`f`0.85(0.75)

0.0033

0.00315

4204

28

0.0033420

1.4

4f

f

f

1.4

ofgreater

yy

c

max

y

c

y

min

1


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Length (m)

V (kN)

Length (m)

As (mm2/mm)


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Shear design

stirrupsforneednosokNVV

kNdbf

V

KNV

c

u

w

c

c

u

,7.1202

4.2411023014006

2885.0

6

'

82.70

3

stirrupsforneednosokNV

V

kNdbf

V

kNV

cu

w

c

c

u

,4.157

2

8.3141030014006

2885.0

6

'

86

3

mmhS

Sthanlessbeshouldmmspacing

90030033

2007

1400

max

max


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Figure 9

The drawing for the stair.


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Column (C1)

212

d

gc

LD

Dd

4933

g

u

cu

3

N.mm8.33x10

1

/2.5IEEI

0.88P

P

bucklingCheck

19.58kNx4.350.3x0.6x25WeightOwn

mm1.35x1012

600x300

12

bhI

968kNP

0.09m0.3x0.30.3hr

29000MPaE4.35m,l,kN/m25

600mmx300mmissectioncrosscolumnAssume

frameunbraced1.5,KAssume


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Column (C1)

1.51K:figure(9)Using

2.78EI/l

EI/l

1.08EI/l

EI/l

beamn

columnu

B

beamn

columnu

A

72.02kN.mhPh

e

M

0.080.030.3

0.015

h

e

3.1P/0.75P1

1

N1019.06)(Kl

EIP

usu

cu

s

5

2

u

2

c

Figure 10

Effective length factor K


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Column (C1)

300mmspacingtieThen

300mm

456mm

300mm

305.6mm

ofsmallesttiesofSpacing

#10issizetieThen

19)#7(choose

1800mm6003000.01AA

0.01use

0.78Ksi895.38MPa/6.

0.60.3

968

A

P

0.2Ksi891.33MPa/6.30.3x0.6x0.

72.02

hA

M

2

gs

min

g

u

g

u

Figure 11

Interaction Diagram


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Figure 12:

The drawing for the column C1.


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Tie-beam (TB1)

The longest tie beam is TB1 which has a length of 7m

which was designed as the critical case. Then, comparedwith the minimum steel area and take the biggest area of

steel:-

In practice, As,min should be greater than the area of steel in

a column that can enough to resist at least 10% of theheavily loaded column load (maximum load is 968 kn)

In practice As,min > 0.5 % Aconcrete of tie beam x-sec


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Length (m)

M (kN.mm)

Length (m)

V (kN)

Figure 13: Moment diagram and shear diagram for TB1.


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For TB1 , As=573 mm2 which is (3 # 16) and compare it with:

10% of the column load (maximum load is 968 kN)

1- As,min =(10% Pu) / (0.9 Fy) =0.1 968 1000 / 0.9 420 = 256 mm2 (2 # 13)

All the tie beams have a cross-section 20cm x 60cm

2- As,min = 0.5 % Aconcrete = 0.005 200 600 = 600mm2 (3 # 16)So, the biggest area is 3 # 16.

For shear (stirrups):

maxs,s

wcmaxs,

svs

sv

VV395.1kN

560200283

2dbf

3

2V

1Check

kN38.57280.164420560

AfydVFind,

957mm0.164

78.52SSo,

S

Asn

fyd

Vs0.164A

#10@280mmchoose

SS

280mmS

989.1mmb

f3A

280mm0.5d

600mm

ofsmallestS

197.6kN560200283

1dbf

3

1V

2Check

max

max

w

yv

max

wcs


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Footing (F1)

94.8kN20.22648.6TB1)(fromPP

291kN40251B11)(fromPP

253.5kN35.5218HB10)(fromPP

LD

LD

LD

2.2m2.2mChoose4.69m150

63.93639.3A

63.93kN)P(P0.1PAssume

AcapacitybearingPPP639.3kN394.8291253.5PP

150kN/m1.5Kg/cmcapacityBearing

F1

2

footing

LDextra

footingextraLD

LD

22

0.95m

0.3m

0.6m

2.2m

2.2m

0.8m


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180.76kN.m)2

0.95(0.952.2227.44)

2

z(LzqM

122.6kN.m)2

0.8

(0.82.2227.44)2

z

(BzqM

227.44kN/m2.22.2

1100.8

A

1.7L1.4Dq

150kN/m136.05kN/m2.22.219.206639.3

APPP

63.93kN19.206kN15)0.4)(240.6(1.50.315)0.4(242.22.2

)h)(lb(1.5)LBh(P

:Check

22ulongu,

11ushortu,

2

chosen

u

22

chosen

extraLD

soilconcretesoilconcreteextra


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12#16)(choose2323.2mm32022000.0033bdA

choose

0.02125420600

600

420

280.850.850.75

f600

600

f

`f`0.85(0.75)

0.0033

0.003154204

28

0.0033420

1.4

4f

f

f

1.4

ofgreater

0.00216

280.85

0.89211

420

280.85

`0.85f`

2R11

f

`0.85f`

0.89MPa891.52kN/m0.08)(0.42.20.9

180.76

bd

MR

entreinforcemLong

2s

minmin

yy

c

max

y

c

y

min

c

n

y

c

2

22u

long

1


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11#16)(choose2178mm30022000.0033A

)choose0.00167(280.85

0.692

11420

280.85

0.69MPa688kN/m0.1)(0.42.20.9

122.6

bd

MR

entreinforcemShort

2s

minmin

2

22u

short

0.95m

0.3m0.6m

2.2m

2.2m

0.8m


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OkVV

1847.09kN

4002320)(300320)(60012

2840.852hd)(bd)(l

12

f4V

750.552kN0.32)0.32)(0.3(0.62.22.2227.44d)d)(b(lBLqV

shearwayTwo

OkVV

527.74kN32022006

280.85Bd

6

f0.85V

265.2kN0.32)(0.952.2227.44d)B(zqV

entreinforcemLong

OkVV

527.74kN32022006

280.85Bd

6

f0.85V

190.14kN0.32)(0.82.2227.44d)B(zqV

entreinforcemshortshearwayOne

cu

c

c

uu

cu

c

c

2uu

cu

c

c

1uu

0.95m

0.3m0.6m

2.2m

2.2m

0.8m


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C1(7#19)columnasentreinforcemsameUse

Safe(Design)PP

2728.8kN(Design)P15.16MPa2.2KsiAg

Pu

figurethisUsing

OK0.010.011600300

1985

A

A

180000mm600300A1100.8kN,P

ColumnNeck

uu

u

g

s

4

gu

Figure 14: Interaction diagram


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Figure 15:

The drawing of the footing F1.

12#162.2m

0.4m

0.85m

12#16


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The environmental aspects and impact of the project should be

controlled by the involved parties to control the bad effects in both

sides either by the environment on the building or on the other way.

- here in UAE, the building usually consumes some of the countrys energy

and water resources and this could be reduced by using green house

technology where solar and wind energies can be used extensively.

- Although the building material considered in this project (i.e., reinforced concrete) isrelatively cheap compared to the steel material, it is, unfortunately, not

environmental friendly

Impact


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Each building in this world represents a unique and creativeidea that is made real by the cooperation of the involved design andconstruction parties.

It is an event that starts by developing the owner ideas on the hands ofengineers to achieve safety, serviceability and creativity of project.

For example, as a social aspects, here in UAE, traditions and thecultural background of the people is totally different from thewestern countries. Thats should be achieved by the architecturaldesign to represent the cultural identity in the scope of the projectdesign beside the modernity.

Impact


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Conclusion and recommendation

The experience gained in the design process is invaluableand represents a major stone in building an efficientstructural designer engineer.

Finally, it is recommended that the design work achievedin this project is originally performed by two groupsusing two different structural systems.

This would provide information enough to compare thecost of each system and get experience with cheapersolutions.

Documents

Structural Design for Low Rise Building