Width of Top Slab = 5.575 mWidth of Bottom Slab = 2.7 mDepth of Box = 3.5 mDL = 586.38 TSDL = 8 T/m (For 400 mm Ballast)

= T/m (For 300 mm Ballast)LL = 524.6 TFy = 415 N/mm2Fck = 45 N/mm2Expansion Gap = 50 mmAxle Load = 25 TUTS of Cable = 356 TFst = 361.05 N/mm2

Cant. Beam

Page 2 of 5

Design of Cantilever Beam

Axle load = 22.5 TImpact Factor for Live load = 1Total live load 45Live load per beam =45x1.325/2 = 29.8125 T

29.8125

150725

370 700

Width,B = 700 mmArea = 725*370+ 0.5 *725(700-370)

= 387875CGx = (370*725*725/2 + (700-370)*725*725/6)/387875

= 325.23 mm

Wt of Beam = 0.936 T/mWt. of Slab = 2.857 T/mTotal DL = 3.793 T/m

SDL = 4 T/m

DLBM = 3.793x(725/1000)^2/2 = 0.997 TmSDLBM = 4x(725/1000)^2/2 = 1.051 TmLLBM = 29.813x(725-150)/1000 = 17.142 Tm

Mult. = 1.4xDLBM + 2xSDLBM +2x LLBMMult. = 37.78 Tm

M = 0.87*Fy*D*As(1-(1.1*Fy*As/(Fck*B*D))

= 0.87*415*D*As(1-(1.1*415*As/(45*700*D))

= 361.05 D*As(1-( 0.014492 *As/D))

= 361.05 D*As- 5.23236

TH. = 0.7 mEff. Depth = 637.5 mm

Area Calculated = 1707.82

mm2

As2

mm2

Cant. Beam

Page 3 of 5

Dia of Bar = 25 mmRequired no of bars = 4

Provide 25mm dia - 4 nos

Area provided = 1963.495

FOR SHEAR:

= 1.4xDL + 2xSDL + 2xLL= 69.275 t

v == 69.275*10000/(637.5*700)

= 1.552

Percentage of longitudinal = 1963.495x 1000 /700x637.5reinforcement = 0.44 %

= (0.27/1.25) x (0.44)^1/3 x (40)^1/3 (As per IRS-CBC 1997)

= 0.562

= 700x Sv x (1.552+0.4-0.562)/(0.87 x fyv)

Asv/Sv = 2.70

Dia of stirupps 10 mmno of legs of stirrups 4

Required spacing of stirrups 116.6 mm

mm2

Vu

Vu /bd

N/mm2

Vc

N/mm2

Asv

Cant. Slab Page 4

Design of Cantilever Slab

Live load (concentrated) = 20 TDisperssing length = 2*1/4*0.725+2*0.5*0.3 = 0.6625 mLive load (UDL) = 20/0.6625 = 30.18868 T/m(widthwise)

30.18868 T/m(widthwise)

725

370 450

Width,B = 1000 mmArea =

= 297250CGx =

= 350.71 mm

DL = 4.14 TSDL = 8 T/m

= 5.8 T

DLBM = 1.4530 TmSDLBM = 2.1025 TmLLBM = 21.886792 Tm

Mult. = 1.4xDLBM + 2xSDLBM + LLBMMult. = 28.13 Tm

M = 0.87*Fy*D*As(1-(1.1*Fy*As/(Fck*B*D))

= 0.87*415*D*As(1-(1.1*415*As/(45*1000*D))

= 361.05 D*As(1-( 0.010144 *As/D))

= 361.05 D*As- 3.662652

TH. = 0.45 mEff. Depth = 387.5 mm

Area Calculated = 2128.994

Dia of Bar = 25 mmRequired spacing = 230 mmProvided spacing = 200 mm

Area provided = 2454.369

mm2

As2

mm2

mm2

Cant. Slab Page 5

FOR SHEAR:

eff_d at edge = 307.500 mmdispersion length =300 + 1.5*307.5 = 761.25dispersion width =300 + 1.5*307.5 = 761.25 but max. = 725

Shear stress = 20*10000/(761.25*725)= 0.362 N/mm2

Percentage of longitudinal = 2454.369*100/(1000*387.5)reinforcement = 0.63 %

= (0.27/1.25) x (0.63)^1/3 x (40)^1/3

= 0.633

Vc

N/mm2