BUS QUEUE SHELTER
ISOLATED FOOTING
Footing F1:-
Reaction from staad output 464 kN
Column Size :- 457x230 mm
Load on column:- 464 kN
Load including self wt. of footing :- 464 kN
Soil bearing capacity:- 124 kN/m2
Area of footing required = 464/124 = 3.7 sqm
Area of footing provided= 1.98x1.98 = 3.92 sqm
SO OK
Net soil pressure 118.36 kN/m2
MuY= 118.36x1.5x{(1.98-0.607)/2}^2 x1/2 = 41.8 kNm
MuX= 118.36x1.5x{(1.98-0.38)/2}^2 x1/2 = 56.8 kNm
Mux=0.133 fck bd 2
d=√{ Mu / 0.133 x Fck x B}= 131 mm
Overall depth provided "D" = 381 mm
deff= 321 mm
MuY=0.87 fy Ast d [1-fy Ast / fck bd]
Mu= 0.87x fy x d x Asty [1- fy Asty / fck x B x d]
8.7Asty^2 - 139635 Asty + 41.84 x 10^6= 0
Required Asty= 305 mm2
Provided:- 125 Nos. 12 Dia bars = 904 mm2
Mux=0.87 fy Ast d [1-fy Ast / fck bd]
Mu= 0.87x fy x d x Astx [1- fy Astx / fck x B x d]
8.7Astx^2 - 139635 Astx + 56.81 x 10^6= 0
Required Astx= 418 mm2
Provided:- 125 Nos. 12 Dia bars = 904 mm2
Hence OK
Check for shear( Punching shear)
Vu= 118.36x1.5x{[ 1.98x 1.98-(0.38+0.321)(0.607+0.321 ) }]= 580.5 KN
tv = 580.5x1000/{2(0.38+0.321 + 0.607 + 0.321 )x 0.321x 1000)}= 0.56 N/sqmm
tc= 0.25X 25 1.25
kS=0.5+bc (should not more than 1)
Ks= 0.5 + (a/b)
a = Length of shorter side of column
b= Length of longer side of column
Ks= 0.5 + (0.23 / 0.457 ) = = 1
If Ks is greater than 1
t'c= Ks X tc , Ks=1
t'c=tc
If Ks is less than 1
t'c= Ks X tc
t'c = 1.25
tv < t c ,
HENCE SAFE IN PUNCHING SHEAR
Check for shear( One way shear)
Vu = 118.36x1.5x(((1.98-0.38)2)-160.5 )= 168
tv = Vu/(bxd) 168.38x1000/(321x1000) = 0.26
P = 100 Ast / bd = 0.28
tc= 0.28 % age of steel 0.3756
tv < t'c
HENCE SAFE IN SHEAR
SAFE
SAFE
SAFE
GRADE
Kn
N/sqmm
Footing F2:-
Reaction from staad output 201 kN
Column Size :- 300x300 mm
Load on column:- 201 kN
Load including self wt. of footing :- 221.1 kN
Soil bearing capacity:- 100 kN/m2
Area of footing required = 221.1/100 = 2.2 sqm
Area of footing provided= 1.52x1.52 = 2.31 sqm
SO OK
Net soil pressure 87.00 kN/m2
MuY= 87x1.5x{(1.52-0.45)/2}^2 x1/2x 1.52 = 28.4 kNm
MuX= 87x1.5x{(1.52-0.45)/2}^2 x1/2x 1.52 = 28.4 kNm
Mux=0.136 fck bd 2
d=√{ Mu / 0.136 x Fck x B}= 83 mm
Overall depth provided "D" = 380 mm
deff= 320 mm
MuY=0.87 fy Ast d [1-fy Ast / fck bd]
Mu= 0.87x fy x d x Asty [1- fy Asty / fck x B x d]
7.2Asty^2 - 139200 Asty + 28.39 x 10^6= 0
Required Asty= 206 mm2
Provided:- 8 Nos. 10 Dia bars = 632 mm2
Mux=0.87 fy Ast d [1-fy Ast / fck bd]
Mu= 0.87x fy x d x Astx [1- fy Astx / fck x B x d]
7.2Astx^2 - 139200 Astx + 28.39 x 10^6= 0
Required Astx= 206 mm2
Provided:- 8 Nos. 10 Dia bars = 632 mm2
Hence OK
Check for shear( Two way shear)
Vu= 87x1.5x{[ 1.52x 1.52-(0.45+0.32)(0.45+0.32 ) }]= 224.1 KN
tv = 224.1x1000/{2(0.45+0.32 + 0.45 + 0.32 )x 0.32x 1000)}= 0.23 N/sqmm
tc= 0.25X 20 1.12
kS=0.5+bc (should not more than 1)
Ks= 0.5 + (a/b)
a = Length of shorter side of column
b= Length of longer side of column
Ks= 0.5 + (0.3 / 0.3 ) = = 1.5
If Ks is greater than 1
t'c= Ks X tc , Ks=1
t'c=tc
If Ks is less than 1
t'c= Ks X tc
t'c = 1.12
tv < t,c
HENCE SAFE IN SHEAR
Footing F3:-
Reaction from staad output 165 kN
Column Size :- 300x600 mm
Load on column:- 165 kN
Load including self wt. of footing :- 181.5 kN
Soil bearing capacity:- 72 kN/m2
Area of footing required = 181.5/72 = 2.5 sqm
Area of footing provided= 1.98x1.83 = 3.62 sqm
SO OK
Net soil pressure 45.54 kN/m2
MuY= 45.54x1.5x{(1.98-0.45)/2}^2 x1/2x 1.83 = 36.6 kNm
MuX= 45.54x1.5x{(1.83-0.75)/2}^2 x1/2x 1.98 = 19.7 kNm
Mux=0.136 fck bd 2
d=√{ Mu / 0.136 x Fck x B}= 61 mm
Overall depth provided "D" = 600 mm
deff= 540 mm
MuY=0.87 fy Ast d [1-fy Ast / fck bd]
Mu= 0.87x fy x d x Asty [1- fy Asty / fck x B x d]
5.9Asty^2 - 234900 Asty + 36.58 x 10^6= 0
Required Asty= 156 mm2
Provided:- 13 Nos. 10 Dia bars = 1027 mm2
Mux=0.87 fy Ast d [1-fy Ast / fck bd]
Mu= 0.87x fy x d x Astx [1- fy Astx / fck x B x d]
5.5Astx^2 - 234900 Astx + 19.72 x 10^6= 0
Required Astx= 84 mm2
Provided:- 14 Nos. 10 Dia bars = 1106 mm2
Hence OK
Check for shear( Two way shear)
Vu= 45.54x1.5x{[ 1.98x 1.83-(0.75+0.54)(0.45+0.54 ) }]= 160.3 KN
tv = 160.3x1000/{2(0.75+0.54 + 0.45 + 0.54 )x 0.54x 1000)}= 0.07 N/sqmm
tc= 0.25X 20 1.12
kS=0.5+bc (should not more than 1)
Ks= 0.5 + (a/b)
a = Length of shorter side of column
b= Length of longer side of column
Ks= 0.5 + (0.3 / 0.6 ) = = 1
If Ks is greater than 1
t'c= Ks X tc , Ks=1
t'c=tc
If Ks is less than 1
t'c= Ks X tc
t'c = 1.12
tv < t,c
HENCE SAFE IN SHEAR
Footing F4:-
Reaction from staad output 619 kN
Column Size :- 680x300 mm
Load on column:- 619 kN
Load including self wt. of footing :- 680.9 kN
Soil bearing capacity:- 72 kN/m2
Area of footing required = 680.9/72 = 9.5 sqm
Area of footing provided= 3.2x3.05 = 9.76 sqm
SO OK
Net soil pressure 63.42 kN/m2
MuY= 63.42x1.5x{(3.2-0.83)/2}^2 x1/2x 3.05 = 203.7 kNm
MuX= 63.42x1.5x{(3.05-0.45)/2}^2 x1/2x 3.2 = 257.2 kNm
Mux=0.136 fck bd 2
d=√{ Mu / 0.136 x Fck x B}= 172 mm
Overall depth provided "D" = 600 mm
deff= 540 mm
MuY=0.87 fy Ast d [1-fy Ast / fck bd]
Mu= 0.87x fy x d x Asty [1- fy Asty / fck x B x d]
3.6Asty^2 - 234900 Asty + 203.72 x 10^6= 0
Required Asty= 879 mm2
Provided:- 21 Nos. 10 Dia bars = 1659 mm2
Mux=0.87 fy Ast d [1-fy Ast / fck bd]
Mu= 0.87x fy x d x Astx [1- fy Astx / fck x B x d]
3.4Astx^2 - 234900 Astx + 257.23 x 10^6= 0
Required Astx= 1113 mm2
Provided:- 22 Nos. 10 Dia bars = 1738 mm2
Hence OK
Check for shear( Two way shear)
Vu= 63.42x1.5x{[ 3.2x 3.05-(0.45+0.54)(0.83+0.54 ) }]= 799.4 KN
tv = 799.4x1000/{2(0.45+0.54 + 0.83 + 0.54 )x 0.54x 1000)}= 0.31 N/sqmm
tc= 0.25X 20 1.12
kS=0.5+bc (should not more than 1)
Ks= 0.5 + (a/b)
a = Length of shorter side of column
b= Length of longer side of column
Ks= 0.5 + (0.3 / 0.68 ) = = 0.94
If Ks is greater than 1
t'c= Ks X tc , Ks=1
t'c=tc
If Ks is less than 1
t'c= Ks X tc
t'c = 1.05
tv < t,c
HENCE SAFE IN SHEAR
Footing F5:-
Reaction from staad output 337 kN
Column Size :- 230x460 mm
Load on column:- 337 kN
Load including self wt. of footing :- 370.7 kN
Soil bearing capacity:- 72 kN/m2
Area of footing required = 370.7/72 = 5.1 sqm
Area of footing provided= 2.44x2.13 = 5.20 sqm
SO OK
Net soil pressure 64.84 kN/m2
MuY= 64.84x1.5x{(2.44-0.38)/2}^2 x1/2x 2.13 = 109.9 kNm
MuX= 64.84x1.5x{(2.13-0.61)/2}^2 x1/2x 2.44 = 68.5 kNm
Mux=0.136 fck bd 2
d=√{ Mu / 0.136 x Fck x B}= 102 mm
Overall depth provided "D" = 600 mm
deff= 540 mm
MuY=0.87 fy Ast d [1-fy Ast / fck bd]
Mu= 0.87x fy x d x Asty [1- fy Asty / fck x B x d]
5.1Asty^2 - 234900 Asty + 109.89 x 10^6= 0
Required Asty= 473 mm2
Provided:- 17 Nos. 10 Dia bars = 1343 mm2
Mux=0.87 fy Ast d [1-fy Ast / fck bd]
Mu= 0.87x fy x d x Astx [1- fy Astx / fck x B x d]
4.5Astx^2 - 234900 Astx + 68.54 x 10^6= 0
Required Astx= 293 mm2
Provided:- 16 Nos. 10 Dia bars = 1264 mm2
Hence OK
Check for shear( Two way shear)
Vu= 64.84x1.5x{[ 2.44x 2.13-(0.61+0.54)(0.38+0.54 ) }]= 402.6 KN
tv = 402.6x1000/{2(0.61+0.54 + 0.38 + 0.54 )x 0.54x 1000)}= 0.18 N/sqmm
tc= 0.25X 20 1.12
kS=0.5+bc (should not more than 1)
Ks= 0.5 + (a/b)
a = Length of shorter side of column
b= Length of longer side of column
Ks= 0.5 + (0.23 / 0.46 ) = = 1
If Ks is greater than 1
t'c= Ks X tc , Ks=1
t'c=tc
If Ks is less than 1
t'c= Ks X tc
t'c = 1.12
tv < t,c
HENCE SAFE IN SHEAR
