face sheet

GAMMON INDIA LIMITEDGAMMON HOUSE, Sharada Terrace,First floor,BelapurPhone: 91-22-61297300, Fax: 91-22-61297450, H.O.22-66614000E-Mail: gammon@gammonindia.comWeb: http://www.gammonindia.com

OFFICE OF ORIGIN:EDMS SectionIn-house Design Section of Gammon India Limited

PROJECT:Nathani Heights

OWNER

OWNER'S CONSULTANT

CLIENT

TITLE:Analysis and design of Precast Staircase

DATE:24/11/2014Document No.Sheet No.1 TO

Date ofRevisionRevision to incorporate observations of client vide their letter reference/minutes of meeting as the case may be, and as refered below:Prepared ByChecked ByIssueNameSignNameSign

14-08-2013R0First submissionPLSMCB

APPROVED BY:

Mukund Butala - Senior General Manager, EDMS

This design is the property of GAMMON INDIA LIMITED. It should not be used, copiedor reproduced without their written permission.

Sheet2INDEX

SR. NO.NAMEPAGE NO.

1Staircase design3 to 5

2Landing Slab Design6 to 9

Sheet3

Design of Staircase

STAIR CASE

Analysis And Design of Staircase4.25m2.293 m2.02.0

0.15

1.0Data:-Grade of Concrete30.0Grade of Steel500.0Height of Stair case 3.35mSpan of Waist Slab2293mmWidth of Landing 2000mmTake Rise 167mmTread 300mmNo. of rises 10No'sNo. of Treads 8No'sLength of Landing4150mmHeight of each Flight1.670mNo. of Flight 2No's

2.0Load Calculations:-Assume Thickness of Waist slab 200mmCover to the waist slab35mmDia. Of Steel12mm(l/20) 114.65mmEffective Depth159mmLive Load per meter1.5KN/mFloor Finish1KN/m R +T = 343.350mmSelf Wt. of Waist Slab5.722KN/mSelf Wt. of Steps2.09KN/mDead Load per Meter7.810KN/mTotal Load on Waist Slab10.310KN/m Total Load on Landing8.222KN/m

10.310KN/m

Reaction at Support=11.820KN

Maximum Bending Moment =6.776KN-m

cbc=10N/mm2st=275N/mm2

Modular ratio, m 280=9.3333xcbcNeutral axis depth constant, kmxcbc=0.253mxcbc +stj1-(k/3)=0.916Q1/2xcbcxjxk=1.160

Required Depth (DR)DR=((Mu*E)/(Q*b))[As Per IS:456]Q=1.160Breadth (b)b=1000mm

DR=76.431mmOK

3.0Main Reinforcement Calculation

R=Mu=0.27Mpabd

Pt=Ast=0.001100bdAst=99.0031307308mm

Main SteelDia of steel =12mmSpacing s=1000*ast/Ast=1143mm c/cProvide Spacing=120mm c/c

Provide 12mm steel at 120 mm c/cAst(Provided.)=942.6mmDistribution SteelAst Required (0.12 x b x d/100)=190.8mmDia of steel =10mmSpacing s=1000*ast/Ast=412mm c/cProvide Spacing=100mm c/cAst(Provided.)=785.5mm

Provide 10mm steel at 100 mm c/c

EL (+) 0.002.25 m2 m2 m2.293 m2 m1.675 mEL (-) 4.00AB

Column Design-LSMColumn Design1.0General DataGrade of concrete =30.0Grade of steel=500.0Cover=45mm2.0Design Calculation

From Staad Pro.

Max. Axial Force (Pu)=960.2KNMax. Moment (My)=130.9KN-mMax. Moment (Mz)=158.95KN-mFactored Max. Axial Force (Pu)=1440.3KNFactored Max. Moment (My)=196.35KN-mFactored Max. Moment (Mz)=238.425KN-m

10mm strriups at 140 mm c/c2.1Effective LengthL =13m12.04.0Leff =0.8L=10.4m(As per IS 456:2000, Table 28)2.2Slenderness Ratio500.0

Leff =20.8> 12DHence the Column is Slender So design it as a Slender Column500.02.3Eccentricities25.08.0emin=l/500 + Dx/30

ex min=42.667> 20mm

ey min=42.667> 20 mm

3.0Longitudinal Reinforcement Calculation[From Table -01 of SP-16]Interpolutionlex=20.8200.2D20.800.218ex=0.218250.313D

Additional MomentsM(ax)=Pu * exM(ax)=157.050KN.mM(ay)=Pu * eyM(ay)=157.050KN.m

Assume percentage of Steel=1.70%

From chart 63 of SP-16

Puz=20N/mmAg

Puz=5000KN

Assuming 25.0Dia. +25.0Dia. +12.0Dia

Along X Directiond'=60.5=0.121D 500

Along Y Directiond'=60.5=0.121D 500

Take d'=0.15D From Table 60 of SP-16, Page 1710.10.15

K1=0.1960.2070.196K2=0.2560.4250.256

Pbx={K1 + K2 * (P/fck)}*fck * b * DPbx=1578.8KN=Pby

Therefore Kx=Puz - PuPuz - PbxKx=1.040

Ky=Puz - PuPuz - PbyKy=1.040

The Additional moments calculated will be multiplied by the values of K

M(ax)=163.408KN.mM(ay)=163.408KN.m

Moments Due to eccentricity

Mux=61.453KNmMuy=61.453KNm

Total MomentsMux=224.861KNmMuy=224.861KNm

The section is to checked for biaxial moments

Pu=0.192Fck x b x D

P=0.06fckFrom Chart -48 of SP-16d'=0.15D

Mu=0.12fck x b x D

Therefore Mux1=435KNmMuy1=435KNm

Mux=0.517Mux1

Muy=0.517Muy1Pu=0.288Puz

Pt=1.7>= 0.8% ( As Per IS 456:2000, Clause 26.5.3.1)Therefore Provide Steel of 1.7%Area of Reinforcement RequiredAst=4250mmProvide No. of Bars8No'sDia of Bar 25mmNo. of Bars4No'sDia of Bar 12mm (Ast)provided = 4379.948mm (Pt)provided = 1.752%

The value of can be obtained by interpolation

=1.059

The strenght of section can be checked by using equation

Mux+Muy