Isolated Footing
539
COMBINED FOOTING C18 & C19 Page 1 of 539 JOB NO. BONGAIGAON CRB DESCRIPTION DATE 26-Jul-09 DESIGNED PCK CUSTOMER NTPC INDIA CHECKED SAG Design Of Combined Foundation FOR COLUMN C18 & C19 0.5 6.2 0.75 4.7 1.6 3 1.6 0.3 1.2 2 0.8 Constants :- Unit Wt Of Soil = 1.8 Density Of Water = 1 Unit Weight Of Concrete = 2.5 Comp. strength of concrete fc = 30 Yield strength of steel fy = 415 Coefficient Of Friction m = 0.5 Net SBC = 10.4 Gross SBC = 14 Gross SBC = 16.6 Shape Of Foundation :- 6.2 m 4.7 m 0.8 m 2 m 0.5 m 0.75 m 0 m (Support Reaction Considered at Base of footing) Section Modulus Zxx = 1 / 6 x 6.2 x 4.7 x 4.7 = 22.827 Section Modulus Zzz = 1 / 6 x 4.7 x 6.2 x 6.2 = 30.112 Calculation Of Soil, Fdn & Pedestal Weights :- Selfweight Of Foundation = 6.2 x 4.7 x 0.8 x 2.5 = 58.28 T Selfweight Of Soil = 1.8 x 1.2 x ( 6.2 x 4.7 - 0.75 x 0.5 x 2 ) = 61.32 T Selfweight Of Pedestal = 2.5 x 0.75 x 0.5 x 0 x 2 = 0 T Buoyant Weight = -1 x 6.2 x 4.7 x 2 = -58.28 T Total weight without buoyancy = 58.28 + 61.32 + 0 = 119.6 T Total weight with buoyancy = 58.28 + 61.32 + 0 + -58.28 = 61.32 T JYOTI STRUCTURE LTD. MUMBAI DESIGN OF COMBINED FOOTING FOR C18 & C19 T/m 3 T/m 3 T/m 3 N/mm 2 N/mm 2 T/m 2 T/m 2 ------ Where increase in SBC is not allowed. T/m 2 ------ Where increase in SBC is allowed.(Wind / EQ 25% increase) Length Of Foundation Lf = Width Of Foundation Wf = Thickness Of Foundation Tf = Founding Depth Df = Length Of Pedestal Lp = Width Of Pedestal Wp = Height Of Pedestal Hp = m 3 m 3 Z X
Transcript of Isolated Footing
COMBINED FOOTING C18 & C19
JOB NO.
JYOTI STRUCTURE LTD. MUMBAI
DESCRIPTION CUSTOMER
DESIGN OF COMBINED FOOTING FOR C18 & C19 NTPC INDIA
BONGAIGAON CRB DATE 26-Jul-09 DESIGNED PCK CHECKED SAG
Design Of Combined Foundation 0.5
FOR COLUMN C18 & C19Z
6.2
0.75
4.7
X
1.6
3
1.6
0.3
1.2 2 0.8
Constants :Unit Wt Of Soil = Density Of Water = Unit Weight Of Concrete = Comp. strength of concrete fc = Yield strength of steel fy = Coefficient Of Friction m = Net SBC = Gross SBC = Gross SBC = Shape Of Foundation :Length Of Foundation Lf = Width Of Foundation Wf = Thickness Of Foundation Tf = Founding Depth Df = Length Of Pedestal Lp = Width Of Pedestal Wp = Height Of Pedestal Hp = 1.8 1 2.5 30 415 0.5 10.4 14 16.6 T/m3 T/m3 T/m3 N/mm2 N/mm2 T/m2 T/m2 ------ Where increase in SBC is not allowed. T/m2 ------ Where increase in SBC is allowed.(Wind / EQ 25% increase)
6.2 4.7 0.8 2 0.5 0.75 0
m m m m m m m
(Support Reaction Considered at Base of footing)
Section Modulus Zxx = 1 / 6 x 6.2 x 4.7 x 4.7 m3 = 22.83 Section Modulus Zzz = 1 / 6 x 4.7 x 6.2 x 6.2 = 30.11 m3
Calculation Of Soil, Fdn & Pedestal Weights :Selfweight Of Foundation = 6.2 x 4.7 x 0.8 x 2.5 = 58.28 T Selfweight Of Soil = 1.8 x 1.2 x ( 6.2 x 4.7 - 0.75 x 0.5 x 2 ) = 61.32 T Selfweight Of Pedestal = 2.5 x 0.75 x 0.5 x 0 x 2 = 0 T Buoyant Weight = -1 x 6.2 x 4.7 x 2 = -58.28 T Total weight without buoyancy = 58.28 + 61.32 + 0 = 119.6 T Total weight with buoyancy = 58.28 + 61.32 + 0 + -58.28 = 61.32 T
Page 1 of 299
COMBINED FOOTING C18 & C19
JOB NO.
JYOTI STRUCTURE LTD. MUMBAICalculation Of Restoring Moment :-
DESCRIPTION CUSTOMER
DESIGN OF COMBINED FOOTING FOR C18 & C19 NTPC INDIA
BONGAIGAON CRB DATE 26-Jul-09 DESIGNED PCK CHECKED SAG
Due to fdn. Weight = 58.28 x 6.2 / 2 = 180.67 Tm Due to fdn. Soil = 61.32 x 6.2 / 2 = 190.09 Tm Due to Pedestal = 0 x 0.8 + 0 x 5.4 = 0 Tm Due to Buoyant weight = -58.28 x 3.1 = -180.67 Total moment without buoyancy = 180.67 + 190.09 + 0 = 370.76 Tm Total moment with buoyancy = 180.67 + 190.09 + 0 -180.67 = 190.09 Tm Support Reactions :- ( At foundation level) All Units in Ton - Meter JOINT LOAD FORCE-X FORCE-Y FORCE-Z MOM-X MOM-Y 234 5 1.5 (DL+LL) 0.55 39.81 -2.82 -4.26 0.97 6 1.2 (DL+LL+EQX) -6.91 3.69 -2.29 -3.39 1.74 7 1.5 (DL+EQX) -8.66 4.16 -2.9 -4.27 2.06 8 0.9DL+1.5EQX -8.87 -11.58 -1.76 -2.56 1.72 9 1.2 (DL+LL-EQX) 7.78 60 -2.23 -3.42 -0.19 10 1.5 (DL-EQX) 9.7 74.55 -2.84 -4.31 -0.34 11 0.9DL-1.5EQX 9.49 58.8 -1.69 -2.59 -0.68 12 1.2 (DL+LL+EQZ) 0.45 39.05 -7.76 -21.81 2.94 13 1.5 (DL+EQZ) 0.54 48.35 -9.74 -27.29 3.56 14 0.9DL+1.5EQZ 0.33 32.61 -8.6 -25.57 3.22 15 1.2 (DL+LL-EQZ) 0.42 24.65 3.24 14.99 -1.39 16 1.5 (DL-EQZ) 0.5 30.35 4.01 18.71 -1.84 17 0.9DL-1.5EQZ 0.29 14.61 5.15 20.42 -2.18 247 5 1.5 (DL+LL) 1.24 6 1.2 (DL+LL+EQX) -8.64 7 1.5 (DL+EQX) -10.81 8 0.9DL+1.5EQX -11.31 9 1.2 (DL+LL-EQX) 10.63 10 1.5 (DL-EQX) 13.27 11 0.9DL-1.5EQX 12.78 12 1.2 (DL+LL+EQZ) 1.14 13 1.5 (DL+EQZ) 1.41 14 0.9DL+1.5EQZ 0.92 15 1.2 (DL+LL-EQZ) 0.85 16 1.5 (DL-EQZ) 1.05 17 0.9DL-1.5EQZ 0.56 73.95 76.96 93.93 65.26 41.36 49.43 20.76 62.12 75.37 46.7 56.21 67.98 39.31 -3.5 -2.95 -3.37 -2.1 -2.65 -2.99 -1.72 -8 -9.68 -8.41 2.41 3.32 4.59 -12.03 -9.9 -11.32 -6.93 -9.36 -10.65 -6.25 -36.28 -44.3 -39.91 17.03 22.34 26.73 -0.01 0.22 0.3 0.29 -0.23 -0.27 -0.27 2.23 2.81 2.8 -2.24 -2.77 -2.78
MOM Z -0.78 16.51 20.67 20.97 -17.75 -22.15 -21.85 -0.72 -0.86 -0.56 -0.53 -0.62 -0.32 -1.56 18.49 23.13 23.75 -20.99 -26.21 -25.6 -1.49 -1.84 -1.22 -1.01 -1.24 -0.63
Check For stability :a) Against Overturing :- (Check is done only for without buoyancy case) Total O/T Moment Restoring Moment Load MOM-Z MOM-X External Soil,Fdn, Total STAAD Due to Fy Load Pedestal 5 1.5 (DL+LL) 2.34 51.22 16.29 55.99 403.88 370.76 6 1.2 (DL+LL+EQX) 109.9 34.99 13.29 145.51 359.94 370.76 7 1.5 (DL+EQX) 43.8 134.65 15.59 179.13 438.72 370.76 8 0.9DL+1.5EQX 44.71 115.25 9.48 160.25 281.65 370.76 9 1.2 (DL+LL-EQX) 38.74 27.96 12.78 67.91 286.27 370.76 10 1.5 (DL-EQX) 48.36 37.68 14.95 87.34 346.64 370.76 11 0.9DL-1.5EQX 47.45 57.07 8.85 104.9 189.56 370.76 12 1.2 (DL+LL+EQZ) 34.61 2.21 58.09 68.78 348.22 370.76 13 1.5 (DL+EQZ) 2.7 40.53 71.59 83.64 424.07 370.76 14 0.9DL+1.5EQZ 1.79 21.14 65.48 69.38 267 370.76 15 1.2 (DL+LL-EQZ) 47.34 1.54 32.02 58.43 297.99 370.76 16 1.5 (DL-EQZ) 1.86 56.44 41.04 71.3 361.28 370.76 17 0.9DL-1.5EQZ 0.95 37.05 47.15 60.56 204.21 370.76
Total 774.64 730.7 809.48 652.41 657.03 717.4 560.32 718.98 794.83 637.76 668.75 732.04 574.97
F.O.S. 13.84 5.02 4.52 4.07 9.68 8.21 5.34 10.45 9.5 9.19 11.45 10.27 9.49
Result Safe Safe Safe Safe Safe Safe Safe Safe Safe Safe Safe Safe Safe
Page 2 of 299
COMBINED FOOTING C18 & C19
JOB NO.
JYOTI STRUCTURE LTD. MUMBAI
DESCRIPTION CUSTOMER
DESIGN OF COMBINED FOOTING FOR C18 & C19 NTPC INDIA
BONGAIGAON CRB DATE 26-Jul-09 DESIGNED PCK CHECKED SAG
b) Against Sliding :- (Check is done only for with buoyancy case) Total Sliding Forces Restoring Forces Load Fx Fz Resultant External Soil,Fdn, Total Load Pedestal 5 1.5 (DL+LL) 1.78 6.32 6.57 113.76 119.6 116.68 6 1.2 (DL+LL+EQX) 15.55 5.24 16.41 80.66 119.6 100.13 7 1.5 (DL+EQX) 19.47 6.27 20.46 98.09 119.6 108.85 8 0.9DL+1.5EQX 20.17 3.85 20.54 53.68 119.6 86.64 9 1.2 (DL+LL-EQX) 18.4 4.88 19.04 101.36 119.6 110.48 10 1.5 (DL-EQX) 22.97 5.83 23.7 123.97 119.6 121.79 11 0.9DL-1.5EQX 22.27 3.41 22.53 79.56 119.6 99.58 12 1.2 (DL+LL+EQZ) 15.76 1.59 15.84 101.17 119.6 110.39 13 1.5 (DL+EQZ) 1.95 19.43 19.53 123.72 119.6 121.66 14 0.9DL+1.5EQZ 1.25 17.01 17.05 79.31 119.6 99.46 15 1.2 (DL+LL-EQZ) 1.27 5.65 5.79 80.86 119.6 100.23 16 1.5 (DL-EQZ) 1.55 7.33 7.49 98.34 119.6 108.97 17 0.9DL-1.5EQZ 0.85 9.75 9.79 53.92 119.6 86.76
F.O.S. 17.76 6.1 5.32 4.22 5.8 5.14 4.42 6.97 6.23 5.83 17.31 14.55 8.86
Result Safe Safe Safe Safe Safe Safe Safe Safe Safe Safe Safe Safe Safe
Check For bearing pressure :Case 1) Without Buoyancy :Load MOM-X MOM-Z 53.56 144.89 178.45 159.96 66.7 86.04 104.52 36.82 43.23 22.93 48.88 58.3 38 Fy 113.76 80.66 98.09 53.68 101.36 123.97 79.56 101.17 123.72 79.31 80.86 98.34 53.92 Total Load Soil,Fdn, Pedestral 119.6 119.6 119.6 119.6 119.6 119.6 119.6 119.6 119.6 119.6 119.6 119.6 119.6 Total Load 233.36 200.26 217.69 173.28 220.96 243.57 199.16 220.77 243.32 198.91 200.46 217.94 173.52 P/A 8.01 6.87 7.47 5.95 7.58 8.36 6.83 7.58 8.35 6.83 6.88 7.48 5.95 Mxx/Zxx Mzz/Zzz 0.71 0.58 0.68 0.42 0.56 0.66 0.39 2.55 3.14 2.87 1.4 1.8 2.07 1.78 4.81 5.93 5.31 2.22 2.86 3.47 1.22 1.44 0.76 1.62 1.94 1.26 pmax 10.5 12.27 14.08 11.68 10.36 11.87 10.69 11.35 12.92 10.46 9.91 11.22 9.28 pmin 5.52 1.48 0.86 0.22 4.81 4.85 2.97 3.81 3.78 3.2 3.85 3.75 2.62 pall 14 16.6 16.6 16.6 16.6 16.6 16.6 16.6 16.6 16.6 16.6 16.6 16.6 Result Safe Safe Safe Safe Safe Safe Safe Safe Safe Safe Safe Safe Safe
5 1.5 (DL+LL) 16.29 6 1.2 (DL+LL+EQX) 13.29 7 1.5 (DL+EQX) 15.59 8 0.9DL+1.5EQX 9.48 9 1.2 (DL+LL-EQX) 12.78 10 1.5 (DL-EQX) 14.95 11 0.9DL-1.5EQX 8.85 12 1.2 (DL+LL+EQZ) 58.09 13 1.5 (DL+EQZ) 71.59 14 0.9DL+1.5EQZ 65.48 15 1.2 (DL+LL-EQZ) 32.02 16 1.5 (DL-EQZ) 41.04 17 0.9DL-1.5EQZ 47.15
Bearing Pressure for Without Buoyancy Case :-
pmax =
14.08
T/sq.M
pmin =
9.28
T/sq.M
Page 3 of 299
COMBINED FOOTING C18 & C19
JOB NO.
JYOTI STRUCTURE LTD. MUMBAI
DESCRIPTION CUSTOMER
DESIGN OF COMBINED FOOTING FOR C18 & C19 NTPC INDIA
BONGAIGAON CRB DATE 26-Jul-09 DESIGNED PCK CHECKED SAG
Check for Pressure at All Four Corners without Buoyancy Case
Z
X
1-2+3
1+2+3 1+2-3 Z
X
1-2-3
Load
P/A Mxx/Zxx 1 2 5 1.5 (DL+LL) 8.01 0.71 6 1.2 (DL+LL+EQX) 6.87 0.58 7 1.5 (DL+EQX) 7.47 0.68 8 0.9DL+1.5EQX 5.95 0.42 9 1.2 (DL+LL-EQX) 7.58 0.56 10 1.5 (DL-EQX) 8.36 0.66 11 0.9DL-1.5EQX 6.83 0.39 12 1.2 (DL+LL+EQZ) 2.55 7.58 13 1.5 (DL+EQZ) 8.35 3.14 14 0.9DL+1.5EQZ 6.83 2.87 15 1.2 (DL+LL-EQZ) 6.88 1.4 16 1.5 (DL-EQZ) 7.48 1.8 17 0.9DL-1.5EQZ 5.95 2.07
Mzz/Zzz 3 1.78 4.81 5.93 5.31 2.22 2.86 3.47 1.22 1.44 0.76 1.62 1.94 1.26
1+2+3 10.5 12.27 14.08 11.68 10.36 11.87 10.69 11.35 12.92 10.46 9.91 11.22 9.28
1-2+3 9.08 11.1 12.71 10.85 9.24 10.56 9.91 6.26 6.65 4.72 7.1 7.62 5.15
1-2-3 5.52 1.48 0.86 0.22 4.81 4.85 2.97 3.81 3.78 3.2 3.85 3.75 2.62
1+2-3 6.95 2.64 2.23 1.05 5.93 6.16 3.75 8.9 10.05 8.94 6.66 7.34 6.75
pmax = pmin =
14.08 0.22
Check for Eccentricity without Buoyancy Case:Load P Mxx 16.29 13.29 15.59 9.48 12.78 14.95 8.85 58.09 71.59 65.48 32.02 41.04 47.15 Mzz 53.56 144.89 178.45 159.96 66.7 86.04 104.52 36.82 43.23 22.93 48.88 58.3 38 ex = Mzz/P 0.23 0.73 0.82 0.93 0.31 0.36 0.53 0.17 0.18 0.12 0.25 0.27 0.22 ez = Mxx/P 0.07 0.07 0.08 0.06 0.06 0.07 0.05 0.27 0.3 0.33 0.16 0.19 0.28 L/6 1.04 1.04 1.04 1.04 1.04 1.04 1.04 1.04 1.04 1.04 1.04 1.04 1.04 B/6 0.79 0.79 0.79 0.79 0.79 0.79 0.79 0.79 0.79 0.79 0.79 0.79 0.79 ex < L/6 ez < B/6 1.4 Hence Safe
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for All Load Cases:Check for Maxi. & Mini. Pressure at Base of Footing:Load Total P/A Case Load 244 5 1.5 (DL+LL) 106.17 ### F5-C30 6 1.2 (DL+LL+EQX) ### 96.49 0 7 1.5 (DL+EQX) 109.44 ### 0 8 0.9DL+1.5EQX 83.26 999.16 0 9 1.2 (DL+LL-EQX) ### 89.15 0 10 1.5 (DL-EQX) 100.27 ### 0 11 0.9DL-1.5EQX 74.09 889.14 0 12 1.2 (DL+LL+EQZ) ### 101.81 0 13 1.5 (DL+EQZ) 116.09 ### 0 14 0.9DL+1.5EQZ 89.91 ### 0 15 1.2 (DL+LL-EQZ) ### 83.83 0 16 1.5 (DL-EQZ) 93.62 ### 0 17 0.9DL-1.5EQZ 67.45 809.34 Joint Mxx/Zxx 4.59 3.55 4.48 2.63 3.79 4.79 2.94 36.6 45.8 43.95 29.27 36.54 38.39 Mzz/Zzz 1.53 29.72 37.1 37.73 32.17 40.26 39.63 1.12 1.45 0.81 1.34 1.72 1.09 pmax 112.29 129.76 151.02 123.62 125.11 145.32 116.66 139.53 163.34 134.67 114.44 131.88 106.93 pall 140 166 166 166 166 166 166 166 166 166 166 166 166 pmin 100.06 63.22 67.87 42.91 53.2 55.23 31.53 64.09 68.85 45.16 53.23 55.37 27.97 Result SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Summary of Bearing Pressure Without Stress Increase:With Stress Increase:pmax = pmax = 163.34 kN/m2 112.29 kN/m2 pmin = 100.06 kN/m2 pmin = 27.97 kN/m2
Load P/A Mxx/Zxx Case (1) (2) 244 5 1.5 (DL+LL) 106.17 4.59 F5-C30 6 1.2 (DL+LL+EQX) 96.49 3.55 0 7 1.5 (DL+EQX) 4.48 109.44 0 8 0.9DL+1.5EQX 2.63 83.26 0 9 1.2 (DL+LL-EQX) 89.15 3.79 0 10 1.5 (DL-EQX) 4.79 100.27 0 11 0.9DL-1.5EQX 2.94 74.09 0 12 1.2 (DL+LL+EQZ) 101.81 36.6 0 13 1.5 (DL+EQZ) 45.8 116.09 0 14 0.9DL+1.5EQZ 43.95 89.91 0 15 1.2 (DL+LL-EQZ) 83.83 29.27 0 16 1.5 (DL-EQZ) 36.54 93.62 0 17 0.9DL-1.5EQZ 38.39 67.45 Joint
Mzz/Zzz (3) 1.53 29.72 37.1 37.73 32.17 40.26 39.63 1.12 1.45 0.81 1.34 1.72 1.09
1+2+3 112.29 129.76 151.02 123.62 125.11 145.32 116.67 139.53 163.34 134.67 114.44 131.88 106.93
1-2+3 103.11 122.66 142.06 118.36 117.53 135.74 110.79 66.33 71.74 46.77 55.9 58.8 30.15
1-2-3 100.05 63.22 67.86 42.9 53.19 55.22 31.53 64.09 68.84 45.15 53.22 55.36 27.97
1+2-3 109.23 70.32 76.82 48.16 60.77 64.8 37.41 137.29 160.44 133.05 111.76 128.44 104.75
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for Overturning & Sliding:Check against Overturning Stabilize Moment Load Joint O/T Case FOS Result Mmt. (Soil,Pe Load on d, Fdn) Ped 244 F5-C30 0 0 0 0 0 0 0 0 0 0 0 5 1.5 (DL+LL) 709.43 37.79 6 1.2 (DL+LL+EQX) 180.55 709.43 7 1.5 (DL+EQX) 709.43 225.44 8 0.9DL+1.5EQX 709.43 227.34 9 1.2 (DL+LL-EQX) 195.35 709.43 10 1.5 (DL-EQX) 709.43 244.55 11 0.9DL-1.5EQX 709.43 238.9 12 1.2 (DL+LL+EQZ) 292.87 709.43 13 1.5 (DL+EQZ) 709.43 366.45 14 0.9DL+1.5EQZ 709.43 351.58 15 1.2 (DL+LL-EQZ) 234.28 709.43 16 1.5 (DL-EQZ) 709.43 292.49 17 0.9DL-1.5EQZ 709.43 307.19 1201.67 1027.35 1260.51 789.32 895.32 1095.48 624.28 1123.1 1380.2 909.01 799.57 975.79 504.59 50.58 9.62 8.74 6.6 8.22 7.39 5.59 6.26 5.71 4.61 6.45 5.77 3.96 SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Check against Sliding Total Hz. Force 29.2 84.09 105.05 105.48 95.51 119.79 114.52 104.18 130.89 119.19 59.08 73.23 84.53 Total FOS for Result Vert. Sliding Load 1274.06 1157.85 1313.29 999.16 1069.83 1203.27 889.14 1221.68 1393.08 1078.95 1005.99 1123.47 809.34 21.82 6.89 6.26 4.74 5.61 5.03 3.89 5.87 5.33 4.53 8.52 7.68 4.79 SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Check For Shear a) Two Way Shear Limit State Method
d/2
d/2
Critical Section = At distance d/2 from face of column Concrete Grade = Column Details Length = Width = Foundation Details Length = Width = Effective Depth = Percentage Of Steel = 30 500 750 N/mm2 mm mm
3000 4000 525 0.26
mm mm mm %
Punching Load Maximum Load on Column = 920.13 kN Punching Shear,P = 920.133 x (( 3 x 4 ) - ( 1.025 x 1.275 )) ( 3 * 4 ) P = 819.93 kN
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Shear Resistance Of Concrete (Vc) = vc x bc x d -----Refer to clause no. 31.6.3.1 of IS 456 where vc = ks x tc ks = 0.5 + c -----should not be greater than 1 c = Short Side Of Column Long Side Of Column c = c = ks = c = 500 750 0.67 1
1.37 N/mm2 bc = Appropriate perimeter at distance d/2 Length of critical section = Width of critical section = Perimeter of critical section = Depth Required = 1025 1275 4600 mm mm mm
819930 1.37 x4600 = 130.11 mm Shear Resistance = 1.37 x 4600 x 525 / 1000 3308 kN163.34 kN/m2
B) One Way Shear1100 0 1625 525 162.16d
162.54
kN/m2
kN/m2
600 750
4000
500 200 1250 525 3000 725 160.44 kN/m2
71.74
kN/m2 125.18 kN/m2
163.34 141.21
kN/m2 kN/m2
Case = With Stress Increase
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Length at Width at
Length at Width at
At Length Maximum Pressure = 141.205 101.01 critical section = 3000 critical section = 1100 Shear Force = 101.005 = 333.32 At Width Maximum Pressure = 162.544 122.34 critical section = 4000 critical section = 725 Shear Force = 122.344 = 354.8
- 25 x 0.6 - 18 x ( 2 - 0.6 ) kN/m2 -- For without Buoynacy Condition With Stress Increse mm mm x 3 x 1.1 kN - 25 x 0.6 - 18 x ( 2 - 0.6 ) kN/m2 -- For without Buoynacy Condition With Stress Increse mm mm x 4 x 0.725 kN 354.8 4000 0.26 kN mm
Designed Shear Stress = Corresponding Length = % Ast = Allowable Shear Stress k Increaae In Shear Stress c
= 0.38 N/mm2 ----Refer Table 19 of IS 456 = 1 ---- Refer clause no. 40.2 of IS 456 = Allowed = 1.25 x 0.3752 x 1 N/mm2 0.47 354798 0.469 x 4000 = 265 mm
= Depth Required =
Design Of Foundation a) Calculation of Reinforcement at Bottom Maximum Pressure = 163.34 -- Without Buoyancy Load Case Pressure due to Soil & Fdn wt = ( 180 + 292.95 ) / ( 3 x 4 ) = 39.41 Net causing moment = 123.93 kN/m2 Maximum Projection of fdn = 1.63 m Bending Moment = 123.931 x 1.625 x 1.625 / 2 = 163.63 kN.m Ast = 0.5 x fck x b x d fy Ast = Mini.% of re-bar = Ast = Use Area of bar = Spacing = Provide Spacing = Area Provided = 1343.05 0.2 1050 16 200.96 149 145 1385.93 mm2 % mm2 mm dia bars mm2 mm
1 -
1-
(4.6 x Mu ) fck x b x d2
mm2
Provide 16 mm dia Bars @ 145 mm spacing bothways
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
b) Calculation of Reinforcement at Top Reinforcement at top is checked for overburden load on top of foundation since 100% of foundation is not in contact with soil. Wt. Of Soil + Fdn wt. = 472.95 kN Area Load = 472.95 / (3 x 4) 39.41 Maxi. Projection of fdn = 1.63 kN/m2 m
Bending Moment = 39.41 x 1.625 x 1.625 / 2 = Ast = 52.03 kN.m 1 1-
0.5 x fck x b x d fy Ast = 416.51 0.1 525 12 113.04 215 215 mm2 %
(4.6 x Mu ) fck x b x d2
Mini % of Re-bar = Ast = Use Area of bar = Spacing = Provide Spacing =
mm2 mm dia bars mm2
mm mm Area Provided = 525.77 mm2 Provide 12 mm dia Bars @ 215 mm spacing bothways
Summary Of Design :Length Of Footing :3000 mm WIdth Of Footing :4000 mm Depth Of Footing :600 mm Reinforcement :At Top :- Provide 12 mm dia Bars @ 215 mm spacing bothways At Bottom :- Provide 16 mm dia Bars @ 145 mm spacing bothways
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
DESIGN OF ISOLATED FOOTING Density Of Concrete = Density Of Soil = Depth Of Foundation = 25 18 2 kN/m3 kN/m m3
FOOTING NO. COLUMN NO.
F6 C14
Net SBC = 104 kN/m2 (As per foundation design basis.) Gross SBC = 104 + 2 x 18 = 140 kN/m (Where increase in SBC is not allowed.) Gross SBC = 104 x 1.25 + 18 x 2 = 166 kN/m2 (Where increase in SBC is allowed.)2
REFER STAAD ANALYSIS FILE SUPPORT REACTION.
FC = FY Length Of Footing L Width Of Footing W Thickness Of Fdn T Width Of Pedestal wp Length Of Pedestal lp Height Of Pedestal Coefficient Of Friction Ground Water Table Ht. = = = = = = = = =L
30 415 3.1 3.1 0.5 0.75 0.5 0 0.5 0
N/mm2 N/mm2 m m m m m m m
1.18
W
Wp
1.18Z
1.3X
Lp
1.3
Load Calculation for Footing & Soil:Self Wt. Of Footing = 25 x 3.1 x 3.1 x 0.5 = 120.13 kN Weight of Soil = [(3.1 x 3.1) - (0.5 x 0.75)] x (2 - 0.5 ) x 18 = 249.35 kN Self Wt. Of Pedestal = 25 x 0.75 x 0.5 x 0 = 0 kN (Not considered here since it is modelled in STAAD) Weight of Footing + Soil = 120.13 + 0 + 249.345 = 369.48 kN
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
JOINT 259 F6-C14
INPUT:- INPUT STAAD SUPPORT REACTION (Unit kN - m) LOAD FORCE-X FORCE-Y FORCE-Z MOM-X MOM-Y MOM Z 5 1.5 (DL+LL) -15.43 548.91 32.24 33.25 -0.38 16.95 6 1.2 (DL+LL+EQX) -71.8 543.25 25.14 25.87 -15.73 168.57 7 1.5 (DL+EQX) -89.91 668.07 32.08 32.77 -19.64 210.83 8 0.9DL+1.5EQX -83.67 452.9 18.93 19.3 -19.49 204 9 1.2 (DL+LL-EQX) 47.11 335.01 26.44 27.33 15.12 -141.44 10 1.5 (DL-EQX) 58.73 407.77 33.71 34.61 18.93 -176.69 11 0.9DL-1.5EQX 64.97 192.6 20.55 21.13 19.07 -183.51 12 1.2 (DL+LL+EQZ) -12.05 404.98 -10.23 -98.77 -7.18 12.82 13 1.5 (DL+EQZ) -15.23 495.23 -12.12 -123.02 -8.94 16.15 14 0.9DL+1.5EQZ -8.99 280.07 -25.28 -136.49 -8.8 9.32 15 1.2 (DL+LL-EQZ) -12.63 473.28 61.8 151.97 6.56 14.3 16 1.5 (DL-EQZ) -15.95 580.6 77.92 190.4 8.24 17.99 17 0.9DL-1.5EQZ -9.72 365.43 64.76 176.92 8.38 11.17
Check for Maximum and Minimum Pressure at the Base:Area of Footing A = 3.1 x 3.1 A = 9.61 m2
Section Modulus Zxx = 1/6 x 3.1 x 3.1 x 3.1 Zxx = 4.97 m3
Section Modulus Zzz = 1/6 x 3.1 x 3.1 x 3.1 Zzz = 4.97 m3
Total Vertical Load P = 548.914 + 369.48 = 918.39 kN P/A = 918.394 / (3.1 x 3.1 ) = 95.57 kN/m2
Mxx/Zxx = 33.25 / 4.966 Mxx/Zxx = 6.696 kN/m2
Mzz/Zzz = 16.952 / 4.966 Mzz/Zzz = 3.414 kN/m2
Maxi.Soil Pressure pmax = 95.566 + 6.696 + 3.414 pmax = 105.68 kN/m2 Less Than Allowable Hence O.K. Mini.Soil Pressure pmin = 95.566 - 6.696 - 3.414 pmin = 85.46 kN/m2 > 0 < 140 kN/m2
No Tension at the Base of Footing
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for Overturning:Overturning Moment = Resultant of Mx & Mz = 37.33 kN.m Calculation of Stabilizing Moment Due to External Load = 548.914 x 3.1 / 2 = 850.82 kN.m Due to wt. of Pedestral = 0 x 1.55 = 0
kN.m
Due to Self Wt. of Fdn = 120.13 x 1.55 = 186.2 kN.m Due to Wt. of Soil = 249.345 x 1.55 = 386.49 kN.m Total Stabilizing moment = 850.82 + 0 + 186.2 + 386.49 = 1423.51 kN.m F.O.S. against Overturning = 1423.51 / 37.33 = 38.13 > 1.2 Hence Safe Check for Sliding:Resultant Shear Force = Total Vertical Load = 35.74 kN
918.39 kN
F.O.S. against Sliding = 918.394 x 0.5 / 35.74 = 12.85 > 1.4 Hence Safe
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for All Load Cases:Check for Maxi. & Mini. Pressure at Base of Footing:Load Total P/A Case Load 259 5 1.5 (DL+LL) 918.39 95.57 F6-C14 6 1.2 (DL+LL+EQX) 912.73 94.98 0 7 1.5 (DL+EQX) 107.97 ### 0 8 0.9DL+1.5EQX 85.58 822.38 0 9 1.2 (DL+LL-EQX) 704.49 73.31 0 10 1.5 (DL-EQX) 80.88 777.25 0 11 0.9DL-1.5EQX 58.49 562.08 0 12 1.2 (DL+LL+EQZ) 774.46 80.59 0 13 1.5 (DL+EQZ) 89.98 864.71 0 14 0.9DL+1.5EQZ 67.59 649.55 0 15 1.2 (DL+LL-EQZ) 842.76 87.7 0 16 1.5 (DL-EQZ) 98.86 950.08 0 17 0.9DL-1.5EQZ 76.47 734.91 Joint Mxx/Zxx 6.7 5.21 6.6 3.89 5.51 6.97 4.26 19.89 24.78 27.49 30.61 38.35 35.63 Mzz/Zzz 3.42 33.95 42.46 41.08 28.49 35.58 36.96 2.59 3.26 1.88 2.88 3.63 2.25 pmax 105.69 134.14 157.03 130.55 107.31 123.43 99.71 103.07 118.02 96.96 121.19 140.84 114.35 pall 140 166 166 166 166 166 166 166 166 166 166 166 166 pmin 85.45 55.82 58.91 40.61 39.31 38.33 17.27 58.11 61.95 38.23 54.21 56.89 38.6 Result SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Summary of Bearing Pressure Without Stress Increase:With Stress Increase:pmax = pmax = 157.03 kN/m2 105.69 kN/m2 pmin = 85.45 kN/m2 pmin = 17.27 kN/m2
Load P/A Mxx/Zxx Case (1) (2) 259 5 1.5 (DL+LL) 95.57 6.7 F6-C14 6 1.2 (DL+LL+EQX) 94.98 5.21 0 7 1.5 (DL+EQX) 107.97 6.6 0 8 0.9DL+1.5EQX 3.89 85.58 0 9 1.2 (DL+LL-EQX) 73.31 5.51 0 10 1.5 (DL-EQX) 6.97 80.88 0 11 0.9DL-1.5EQX 4.26 58.49 0 12 1.2 (DL+LL+EQZ) 80.59 19.89 0 13 1.5 (DL+EQZ) 24.78 89.98 0 14 0.9DL+1.5EQZ 27.49 67.59 0 15 1.2 (DL+LL-EQZ) 87.7 30.61 0 16 1.5 (DL-EQZ) 38.35 98.86 0 17 0.9DL-1.5EQZ 35.63 76.47 Joint
Mzz/Zzz (3) 3.42 33.95 42.46 41.08 28.49 35.58 36.96 2.59 3.26 1.88 2.88 3.63 2.25
1+2+3 105.69 134.14 157.03 130.55 107.31 123.43 99.71 103.07 118.02 96.96 121.19 140.84 114.35
1-2+3 92.29 123.72 143.83 122.77 96.29 109.49 91.19 63.29 68.46 41.98 59.97 64.14 43.09
1-2-3 85.45 55.82 58.91 40.61 39.31 38.33 17.27 58.11 61.94 38.22 54.21 56.88 38.59
1+2-3 98.85 66.24 72.11 48.39 50.33 52.27 25.79 97.89 111.5 93.2 115.43 133.58 109.85
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for Overturning & Sliding:Check against Overturning Stabilize Moment Load Joint O/T Case FOS Result Mmt. (Soil,Pe Load on d, Fdn) Ped 259 F6-C14 0 0 0 0 0 0 0 0 0 0 0 5 1.5 (DL+LL) 572.69 37.32 6 1.2 (DL+LL+EQX) 170.54 572.69 7 1.5 (DL+EQX) 572.69 213.36 8 0.9DL+1.5EQX 572.69 204.91 9 1.2 (DL+LL-EQX) 144.06 572.69 10 1.5 (DL-EQX) 572.69 180.04 11 0.9DL-1.5EQX 572.69 184.73 12 1.2 (DL+LL+EQZ) 99.6 572.69 13 1.5 (DL+EQZ) 572.69 124.07 14 0.9DL+1.5EQZ 572.69 136.81 15 1.2 (DL+LL-EQZ) 152.64 572.69 16 1.5 (DL-EQZ) 572.69 191.25 17 0.9DL-1.5EQZ 572.69 177.27 850.82 842.05 1035.51 702 519.27 632.04 298.53 627.73 767.62 434.11 733.59 899.94 566.43 38.15 8.3 7.54 6.23 7.58 6.7 4.72 12.06 10.81 7.36 8.56 7.71 6.43 SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Check against Sliding Total Hz. Force 35.74 76.07 95.46 85.79 54.02 67.72 68.14 15.81 19.46 26.83 63.08 79.53 65.48 Total FOS for Result Vert. Sliding Load 918.39 912.73 1037.55 822.38 704.49 777.25 562.08 774.46 864.71 649.55 842.76 950.08 734.91 12.85 6 5.44 4.8 6.53 5.74 4.13 24.5 22.22 12.11 6.68 5.98 5.62 SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Check For Shear a) Two Way Shear Limit State Method
d/2
d/2
Critical Section = At distance d/2 from face of column Concrete Grade = Column Details Length = Width = Foundation Details Length = Width = Effective Depth = Percentage Of Steel = 30 500 750 N/mm2 mm mm
3100 3100 425 0.24
mm mm mm %
Punching Load Maximum Load on Column = 668.07 kN Punching Shear,P = 668.07 x (( 3.1 x 3.1 ) - ( 0.925 x 1.175 )) ( 3.1 * 3.1 ) P = 592.52 kN
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Shear Resistance Of Concrete (Vc) = vc x bc x d -----Refer to clause no. 31.6.3.1 of IS 456 where vc = ks x tc ks = 0.5 + c -----should not be greater than 1 c = Short Side Of Column Long Side Of Column c = c = ks = c = 500 750 0.67 1
1.37 N/mm2 bc = Appropriate perimeter at distance d/2 Length of critical section = Width of critical section = Perimeter of critical section = Depth Required = 925 1175 4200 mm mm mm
592520 1.37 x4200 = 102.98 mm Shear Resistance = 1.37 x 4200 x 425 / 1000 2445 kN157.03 kN/m2
B) One Way Shear750 0 1175 425 124.84d
136.48
kN/m2
kN/m2
500 750
3100
500 200 1300 425 3100 875 72.11 kN/m2
143.83
kN/m2 151.49 kN/m2
157.03 153.3
kN/m2 kN/m2
Case = With Stress Increase
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Length at Width at
Length at Width at
At Length Maximum Pressure = 153.301 - 25 x 0.5 - 18 x ( 2 113.8 kN/m2 -- For without critical section = 3100 mm critical section = 750 mm Shear Force = 113.801 x 3.1 x 0.75 = 264.59 kN At Width Maximum Pressure = 136.481 - 25 x 0.5 - 18 x ( 2 96.98 kN/m2 -- For without critical section = 3100 mm critical section = 875 mm Shear Force = 96.981 x 3.1 x 0.875 = 263.06 kN Designed Shear Stress = Corresponding Length = % Ast = Allowable Shear Stress k Increaae In Shear Stress c 264.59 3100 0.24 kN mm
0.5 )Buoynacy Condition With Stress Increse
0.5 )Buoynacy Condition With Stress Increse
= 0.62 N/mm2 ----Refer Table 19 of IS 456 = 1 ---- Refer clause no. 40.2 of IS 456 = Allowed = 1.25 x 0.62 x 1 N/mm2 0.78 264588 0.775 x 3100 = 186 mm
= Depth Required =
Design Of Foundation a) Calculation of Reinforcement at Bottom Maximum Pressure = 157.03 -- Without Buoyancy Load Case Pressure due to Soil & Fdn wt = ( 120.13 + 249.345 ) / ( 3.1 x 3.1 ) = 38.45 Net causing moment = 118.58 kN/m2 Maximum Projection of fdn = 1.3 m Bending Moment = 118.576 x 1.3 x 1.3 / 2 = 100.2 kN.m Ast = 0.5 x fck x b x d fy Ast = Mini.% of re-bar = Ast = Use Area of bar = Spacing = Provide Spacing = Area Provided = 1013.41 0.2 850 16 200.96 198 195 1030.56 mm2 % mm2 mm dia bars mm2 mm
1 -
1-
(4.6 x Mu ) fck x b x d2
mm2
Provide 16 mm dia Bars @ 195 mm spacing bothways
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
b) Calculation of Reinforcement at Top Reinforcement at top is checked for overburden load on top of foundation since 100% of foundation is not in contact with soil. Wt. Of Soil + Fdn wt. = 369.48 kN Area Load = 369.475 / (3.1 x 3.1) 38.45 Maxi. Projection of fdn = 1.3 kN/m2 m
Bending Moment = 38.45 x 1.3 x 1.3 / 2 = Ast = 32.49 kN.m 1 1-
0.5 x fck x b x d fy Ast = 321.12 0.1 425 12 113.04 265 265 mm2 %
(4.6 x Mu ) fck x b x d2
Mini % of Re-bar = Ast = Use Area of bar = Spacing = Provide Spacing =
mm2 mm dia bars mm2
mm mm Area Provided = 426.57 mm2 Provide 12 mm dia Bars @ 265 mm spacing bothways
Summary Of Design :Length Of Footing :3100 mm WIdth Of Footing :3100 mm Depth Of Footing :500 mm Reinforcement :At Top :- Provide 12 mm dia Bars @ 265 mm spacing bothways At Bottom :- Provide 16 mm dia Bars @ 195 mm spacing bothways
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
DESIGN OF ISOLATED FOOTING Density Of Concrete = Density Of Soil = Depth Of Foundation = 25 18 2 kN/m3 kN/m m3
FOOTING NO. COLUMN NO.
F6 C31
Net SBC = 104 kN/m2 (As per foundation design basis.) Gross SBC = 104 + 2 x 18 = 140 kN/m (Where increase in SBC is not allowed.) Gross SBC = 104 x 1.25 + 18 x 2 = 166 kN/m2 (Where increase in SBC is allowed.)2
REFER STAAD ANALYSIS FILE SUPPORT REACTION.
FC = FY Length Of Footing L Width Of Footing W Thickness Of Fdn T Width Of Pedestal wp Length Of Pedestal lp Height Of Pedestal Coefficient Of Friction Ground Water Table Ht. = = = = = = = = =L
30 415 3.1 3.1 0.5 0.75 0.5 0 0.5 0
N/mm2 N/mm2 m m m m m m m
1.18
W
Wp
1.18Z
1.3X
Lp
1.3
Load Calculation for Footing & Soil:Self Wt. Of Footing = 25 x 3.1 x 3.1 x 0.5 = 120.13 kN Weight of Soil = [(3.1 x 3.1) - (0.5 x 0.75)] x (2 - 0.5 ) x 18 = 249.35 kN Self Wt. Of Pedestal = 25 x 0.75 x 0.5 x 0 = 0 kN (Not considered here since it is modelled in STAAD) Weight of Footing + Soil = 120.13 + 0 + 249.345 = 369.48 kN
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
JOINT 245 F6-C31
INPUT:- INPUT STAAD SUPPORT REACTION (Unit kN - m) LOAD FORCE-X FORCE-Y FORCE-Z MOM-X MOM-Y MOM Z 5 1.5 (DL+LL) -15.25 429.72 -12.38 -16.9 0.92 16.49 6 1.2 (DL+LL+EQX) -69.98 445.8 -10.43 -14.81 19.3 165.71 7 1.5 (DL+EQX) -87.64 550.41 -13.12 -18.53 24.03 207.25 8 0.9DL+1.5EQX -81.47 381.26 -8.14 -11.77 23.7 200.61 9 1.2 (DL+LL-EQX) 45.58 241.75 -9.37 -12.23 -17.83 -139.33 10 1.5 (DL-EQX) 56.82 295.34 -11.81 -15.31 -22.38 -174.05 11 0.9DL-1.5EQX 62.98 126.19 -6.82 -8.54 -22.71 -180.69 12 1.2 (DL+LL+EQZ) -12.52 428.92 -53.43 -147.17 -5.79 14.04 13 1.5 (DL+EQZ) -15.81 529.31 -66.87 -183.99 -7.33 17.66 14 0.9DL+1.5EQZ -9.65 360.16 -61.89 -177.22 -7.66 11.02 15 1.2 (DL+LL-EQZ) -11.88 258.62 33.63 120.14 7.26 12.34 16 1.5 (DL-EQZ) -15.01 316.44 41.94 150.15 8.98 15.54 17 0.9DL-1.5EQZ -8.85 147.29 46.93 156.92 8.65 8.9
Check for Maximum and Minimum Pressure at the Base:Area of Footing A = 3.1 x 3.1 A = 9.61 m2
Section Modulus Zxx = 1/6 x 3.1 x 3.1 x 3.1 Zxx = 4.97 m3
Section Modulus Zzz = 1/6 x 3.1 x 3.1 x 3.1 Zzz = 4.97 m3
Total Vertical Load P = 429.716 + 369.48 = 799.2 kN P/A = 799.196 / (3.1 x 3.1 ) = 83.16 kN/m2
Mxx/Zxx = 16.896 / 4.966 Mxx/Zxx = 3.403 kN/m2
Mzz/Zzz = 16.486 / 4.966 Mzz/Zzz = 3.320 kN/m2
Maxi.Soil Pressure pmax = 83.163 + 3.403 + 3.32 pmax = 89.89 kN/m2 < 140 kN/m2
Less Than Allowable Hence O.K. Mini.Soil Pressure pmin = 83.163 - 3.403 - 3.32 pmin = 76.44 kN/m2 > 0
No Tension at the Base of Footing
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for Overturning:Overturning Moment = Resultant of Mx & Mz = 23.61 kN.m Calculation of Stabilizing Moment Due to External Load = 429.716 x 3.1 / 2 = 666.06 kN.m Due to wt. of Pedestral = 0 x 1.55 = 0
kN.m
Due to Self Wt. of Fdn = 120.13 x 1.55 = 186.2 kN.m Due to Wt. of Soil = 249.345 x 1.55 = 386.49 kN.m Total Stabilizing moment = 666.06 + 0 + 186.2 + 386.49 = 1238.75 kN.m F.O.S. against Overturning = 1238.75 / 23.61 = 52.47 > 1.2 Hence Safe Check for Sliding:Resultant Shear Force = Total Vertical Load = 19.65 kN
799.2 kN
F.O.S. against Sliding = 799.196 x 0.5 / 19.65 = 20.34 > 1.4 Hence Safe
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for All Load Cases:Check for Maxi. & Mini. Pressure at Base of Footing:Load Total P/A Case Load 245 5 1.5 (DL+LL) 799.2 83.16 F6-C31 6 1.2 (DL+LL+EQX) 815.28 84.84 0 7 1.5 (DL+EQX) 95.72 919.89 0 8 0.9DL+1.5EQX 78.12 750.74 0 9 1.2 (DL+LL-EQX) 611.23 63.6 0 10 1.5 (DL-EQX) 69.18 664.82 0 11 0.9DL-1.5EQX 51.58 495.67 0 12 1.2 (DL+LL+EQZ) 798.4 83.08 0 13 1.5 (DL+EQZ) 93.53 898.79 0 14 0.9DL+1.5EQZ 75.93 729.64 0 15 1.2 (DL+LL-EQZ) 628.1 65.36 0 16 1.5 (DL-EQZ) 71.38 685.92 0 17 0.9DL-1.5EQZ 53.77 516.77 Joint Mxx/Zxx 3.41 2.99 3.74 2.37 2.47 3.09 1.73 29.64 37.06 35.69 24.2 30.24 31.6 Mzz/Zzz 3.32 33.37 41.74 40.4 28.06 35.05 36.39 2.83 3.56 2.22 2.49 3.13 1.8 pmax 89.89 121.2 141.2 120.89 94.13 107.32 89.7 115.55 134.15 113.84 92.05 104.75 87.17 pall 140 166 166 166 166 166 166 166 166 166 166 166 166 pmin 76.44 48.48 50.25 35.36 33.08 31.05 13.46 50.62 52.91 38.02 38.67 38.01 20.38 Result SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Summary of Bearing Pressure Without Stress Increase:With Stress Increase:pmax = pmax = 141.2 kN/m2 89.89 kN/m2 pmin = 76.44 kN/m2 pmin = 13.46 kN/m2
Load P/A Mxx/Zxx Case (1) (2) 245 5 1.5 (DL+LL) 83.16 3.41 F6-C31 6 1.2 (DL+LL+EQX) 84.84 2.99 0 7 1.5 (DL+EQX) 3.74 95.72 0 8 0.9DL+1.5EQX 2.37 78.12 0 9 1.2 (DL+LL-EQX) 63.6 2.47 0 10 1.5 (DL-EQX) 3.09 69.18 0 11 0.9DL-1.5EQX 1.73 51.58 0 12 1.2 (DL+LL+EQZ) 83.08 29.64 0 13 1.5 (DL+EQZ) 37.06 93.53 0 14 0.9DL+1.5EQZ 35.69 75.93 0 15 1.2 (DL+LL-EQZ) 65.36 24.2 0 16 1.5 (DL-EQZ) 30.24 71.38 0 17 0.9DL-1.5EQZ 31.6 53.77 Joint
Mzz/Zzz (3) 3.32 33.37 41.74 40.4 28.06 35.05 36.39 2.83 3.56 2.22 2.49 3.13 1.8
1+2+3 89.89 121.2 141.2 120.89 94.13 107.32 89.7 115.55 134.15 113.84 92.05 104.75 87.17
1-2+3 83.07 115.22 133.72 116.15 89.19 101.14 86.24 56.27 60.03 42.46 43.65 44.27 23.97
1-2-3 76.43 48.48 50.24 35.35 33.07 31.04 13.46 50.61 52.91 38.02 38.67 38.01 20.37
1+2-3 83.25 54.46 57.72 40.09 38.01 37.22 16.92 109.89 127.03 109.4 87.07 98.49 83.57
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for Overturning & Sliding:Check against Overturning Stabilize Moment Load Joint O/T Case FOS Result Mmt. (Soil,Pe Load on d, Fdn) Ped 245 F6-C31 0 0 0 0 0 0 0 0 0 0 0 5 1.5 (DL+LL) 572.69 23.61 6 1.2 (DL+LL+EQX) 166.37 572.69 7 1.5 (DL+EQX) 572.69 208.08 8 0.9DL+1.5EQX 572.69 200.96 9 1.2 (DL+LL-EQX) 139.87 572.69 10 1.5 (DL-EQX) 572.69 174.73 11 0.9DL-1.5EQX 572.69 180.89 12 1.2 (DL+LL+EQZ) 147.84 572.69 13 1.5 (DL+EQZ) 572.69 184.84 14 0.9DL+1.5EQZ 572.69 177.57 15 1.2 (DL+LL-EQZ) 120.77 572.69 16 1.5 (DL-EQZ) 572.69 150.95 17 0.9DL-1.5EQZ 572.69 157.17 666.06 691 853.14 590.96 374.71 457.78 195.6 664.84 820.44 558.26 400.87 490.48 228.3 52.48 7.6 6.86 5.8 6.78 5.9 4.25 8.38 7.54 6.37 8.07 7.05 5.1 SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Check against Sliding Total Hz. Force 19.64 70.76 88.61 81.88 46.53 58.03 63.35 54.87 68.72 62.63 35.66 44.55 47.75 Total FOS for Result Vert. Sliding Load 799.2 815.28 919.89 750.74 611.23 664.82 495.67 798.4 898.79 729.64 628.1 685.92 516.77 20.35 5.77 5.2 4.59 6.57 5.73 3.92 7.28 6.54 5.83 8.81 7.7 5.42 SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Check For Shear a) Two Way Shear Limit State Method
d/2
d/2
Critical Section = At distance d/2 from face of column Concrete Grade = Column Details Length = Width = Foundation Details Length = Width = Effective Depth = Percentage Of Steel = 30 500 750 N/mm2 mm mm
3100 3100 425 0.21
mm mm mm %
Punching Load Maximum Load on Column = 550.41 kN Punching Shear,P = 550.41 x (( 3.1 x 3.1 ) - ( 0.925 x 1.175 )) ( 3.1 * 3.1 ) P = 488.16 kN
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Shear Resistance Of Concrete (Vc) = vc x bc x d -----Refer to clause no. 31.6.3.1 of IS 456 where vc = ks x tc ks = 0.5 + c -----should not be greater than 1 c = Short Side Of Column Long Side Of Column c = c = ks = c = 500 750 0.67 1
1.37 N/mm2 bc = Appropriate perimeter at distance d/2 Length of critical section = Width of critical section = Perimeter of critical section = Depth Required = 925 1175 4200 mm mm mm
488160 1.37 x4200 = 84.84 mm Shear Resistance = 1.37 x 4200 x 425 / 1000 2445 kN141.2 kN/m2
B) One Way Shear750 0 1175 425 109.56d
121.01
kN/m2
kN/m2
500 750
3100
500 200 1300 425 3100 875 57.72 kN/m2
133.72
kN/m2 138.07 kN/m2
141.2 139.09
kN/m2 kN/m2
Case = With Stress Increase
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Length at Width at
Length at Width at
At Length Maximum Pressure = 139.092 - 25 x 99.59 kN/m2 critical section = 3100 mm critical section = 750 mm Shear Force = 99.592 x 3.1 x = 231.55 kN At Width Maximum Pressure = 121.007 - 25 x 81.51 kN/m2 critical section = 3100 mm critical section = 875 mm Shear Force = 81.507 x 3.1 x = 221.09 kN Designed Shear Stress = Corresponding Length = % Ast = Allowable Shear Stress k Increaae In Shear Stress c
0.5 - 18 x ( 2 - 0.5 )-- For without Buoynacy Condition With Stress Increse
0.75
0.5 - 18 x ( 2 - 0.5 )-- For without Buoynacy Condition With Stress Increse
0.875
231.55 3100 0.21
kN mm
= 0.34 N/mm2 ----Refer Table 19 of IS 456 = 1 ---- Refer clause no. 40.2 of IS 456 = Allowed = 1.25 x 0.338 x 1 N/mm2 0.42 231552 0.4225 x 3100 = 252 mm
= Depth Required =
Design Of Foundation a) Calculation of Reinforcement at Bottom Maximum Pressure = 141.2 -- Without Buoyancy Load Case Pressure due to Soil & Fdn wt = ( 120.13 + 249.345 ) / ( 3.1 x 3.1 ) = 38.45 Net causing moment = 102.75 kN/m2 Maximum Projection of fdn = 1.3 m Bending Moment = 102.753 x 1.3 x 1.3 / 2 = 86.83 kN.m Ast = 0.5 x fck x b x d fy Ast = Mini.% of re-bar = Ast = Use Area of bar = Spacing = Provide Spacing = Area Provided = 874.09 0.2 850 16 200.96 229 225 893.16 mm2 % mm2 mm dia bars mm2 mm
1 -
1-
(4.6 x Mu ) fck x b x d2
mm2
Provide 16 mm dia Bars @ 225 mm spacing bothways
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
b) Calculation of Reinforcement at Top Reinforcement at top is checked for overburden load on top of foundation since 100% of foundation is not in contact with soil. Wt. Of Soil + Fdn wt. = 369.48 kN Area Load = 369.475 / (3.1 x 3.1) 38.45 Maxi. Projection of fdn = 1.3 kN/m2 m
Bending Moment = 38.45 x 1.3 x 1.3 / 2 = Ast = 32.49 kN.m 1 1-
0.5 x fck x b x d fy Ast = 321.12 0.1 425 12 113.04 265 265 mm2 %
(4.6 x Mu ) fck x b x d2
Mini % of Re-bar = Ast = Use Area of bar = Spacing = Provide Spacing =
mm2 mm dia bars mm2
mm mm Area Provided = 426.57 mm2 Provide 12 mm dia Bars @ 265 mm spacing bothways
Summary Of Design :Length Of Footing :3100 mm WIdth Of Footing :3100 mm Depth Of Footing :500 mm Reinforcement :At Top :- Provide 12 mm dia Bars @ 265 mm spacing bothways At Bottom :- Provide 16 mm dia Bars @ 225 mm spacing bothways
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
DESIGN OF ISOLATED FOOTING Density Of Concrete = Density Of Soil = Depth Of Foundation = 25 18 2 kN/m3 kN/m m3
FOOTING NO. COLUMN NO.
F7 C15
Net SBC = 104 kN/m2 (As per foundation design basis.) Gross SBC = 104 + 2 x 18 = 140 kN/m (Where increase in SBC is not allowed.) Gross SBC = 104 x 1.25 + 18 x 2 = 166 kN/m2 (Where increase in SBC is allowed.)2
REFER STAAD ANALYSIS FILE SUPPORT REACTION.
FC = FY Length Of Footing L Width Of Footing W Thickness Of Fdn T Width Of Pedestal wp Length Of Pedestal lp Height Of Pedestal Coefficient Of Friction Ground Water Table Ht. = = = = = = = = =L
30 415 3 3.6 0.5 0.75 0.5 0 0.5 0
N/mm2 N/mm2 m m m m m m m
1.43
W
Wp
1.43Z
1.25X
Lp
1.25
Load Calculation for Footing & Soil:Self Wt. Of Footing = 25 x 3 x 3.6 x 0.5 = 135 kN Weight of Soil = [(3 x 3.6) - (0.5 x 0.75)] x (2 - 0.5 ) x 18 = 281.48 kN Self Wt. Of Pedestal = 25 x 0.75 x 0.5 x 0 = 0 kN (Not considered here since it is modelled in STAAD) Weight of Footing + Soil = 135 + 0 + 281.475 = 416.48 kN
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
JOINT 270 F7-C15
INPUT:- INPUT STAAD SUPPORT REACTION (Unit kN - m) LOAD FORCE-X FORCE-Y FORCE-Z MOM-X 5 1.5 (DL+LL) 5.84 704.05 -11.74 -22.67 6 1.2 (DL+LL+EQX) -17.99 555.73 -9.87 -18.71 7 1.5 (DL+EQX) -22.38 681.16 -12.45 -23.63 8 0.9DL+1.5EQX -24.76 404.94 -7.71 -14.47 9 1.2 (DL+LL-EQX) 27.33 570.75 -8.92 -17.56 10 1.5 (DL-EQX) 34.26 699.94 -11.27 -22.19 11 0.9DL-1.5EQX 31.89 423.72 -6.52 -13.02 12 1.2 (DL+LL+EQZ) 5.07 563.19 -86.27 -224.04 13 1.5 (DL+EQZ) 6.44 690.49 -107.96 -280.29 14 0.9DL+1.5EQZ 4.06 414.27 -103.21 -271.12 15 1.2 (DL+LL-EQZ) 4.27 563.29 67.48 187.77 16 1.5 (DL-EQZ) 5.44 690.61 84.24 234.47 17 0.9DL-1.5EQZ 3.07 414.39 88.98 243.64
MOM-Y 2.64 7.26 9.09 8.03 -3.03 -3.79 -4.85 -4.7 -5.87 -6.93 8.93 11.17 10.11
MOM Z -13.92 162.89 203.54 209.13 -185.16 -231.53 -225.93 -11.99 -15.07 -9.47 -10.28 -12.93 -7.33
Check for Maximum and Minimum Pressure at the Base:Area of Footing A = 3 x 3.6 A = 10.8 m2
Section Modulus Zxx = 1/6 x 3 x 3.6 x 3.6 Zxx = 6.48 m3
Section Modulus Zzz = 1/6 x 3.6 x 3 x 3 Zzz = 5.4 m3
Total Vertical Load P = 704.052 + 416.48 = 1120.53 kN P/A = 1120.532 / (3 x 3.6 ) = 103.75 kN/m2
Mxx/Zxx = 22.67 / 6.48 Mxx/Zxx = 3.499 kN/m2
Mzz/Zzz = 13.919 / 5.4 Mzz/Zzz = 2.578 kN/m2
Maxi.Soil Pressure pmax = 103.753 + 3.499 + 2.578 pmax = 109.83 kN/m2 Less Than Allowable Hence O.K. Mini.Soil Pressure pmin = 103.753 - 3.499 - 2.578 pmin = 97.68 kN/m2 > 0 < 140 kN/m2
No Tension at the Base of Footing
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for Overturning:Overturning Moment = Resultant of Mx & Mz = 26.61 kN.m Calculation of Stabilizing Moment Due to External Load = 704.052 x 3 / 2 = 1056.08 kN.m Due to wt. of Pedestral = 0 x 1.5 = 0
kN.m
Due to Self Wt. of Fdn = 135 x 1.5 = 202.5 kN.m Due to Wt. of Soil = 281.475 x 1.5 = 422.22 kN.m Total Stabilizing moment = 1056.08 + 0 + 202.5 + 422.22 = 1680.8 kN.m F.O.S. against Overturning = 1680.8 / 26.61 = 63.16 > 1.2 Hence Safe Check for Sliding:Resultant Shear Force = 13.12 kN
Total Vertical Load = 1120.53 kN F.O.S. against Sliding = 1120.532 x 0.5 / 13.12 = 42.71 > 1.4 Hence Safe
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for All Load Cases:Check for Maxi. & Mini. Pressure at Base of Footing:Load Total P/A Case Load 270 5 1.5 (DL+LL) 103.75 ### F7-C15 6 1.2 (DL+LL+EQX) 972.21 90.02 0 7 1.5 (DL+EQX) 101.63 ### 0 8 0.9DL+1.5EQX 76.06 821.42 0 9 1.2 (DL+LL-EQX) 987.23 91.41 0 10 1.5 (DL-EQX) 103.37 ### 0 11 0.9DL-1.5EQX 77.8 840.2 0 12 1.2 (DL+LL+EQZ) 979.67 90.71 0 13 1.5 (DL+EQZ) 102.5 ### 0 14 0.9DL+1.5EQZ 76.92 830.75 0 15 1.2 (DL+LL-EQZ) 979.77 90.72 0 16 1.5 (DL-EQZ) 102.51 ### 0 17 0.9DL-1.5EQZ 76.93 830.87 Joint Mxx/Zxx 3.5 2.89 3.65 2.24 2.71 3.43 2.01 34.58 43.26 41.85 28.98 36.19 37.6 Mzz/Zzz 2.58 30.17 37.7 38.73 34.29 42.88 41.84 2.23 2.79 1.76 1.91 2.4 1.36 pmax 109.83 123.08 142.98 117.03 128.41 149.68 121.65 127.52 148.55 120.53 121.61 141.1 115.89 pall 140 166 166 166 166 166 166 166 166 166 166 166 166 pmin 97.68 56.96 60.29 35.09 54.42 57.07 33.95 53.91 56.45 33.32 59.83 63.92 37.98 Result SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Summary of Bearing Pressure Without Stress Increase:With Stress Increase:pmax = pmax = 149.68 kN/m2 109.83 kN/m2 pmin = 97.68 kN/m2 pmin = 33.32 kN/m2
Load P/A Mxx/Zxx Case (1) (2) 270 5 1.5 (DL+LL) 103.75 3.5 F7-C15 6 1.2 (DL+LL+EQX) 90.02 2.89 0 7 1.5 (DL+EQX) 3.65 101.63 0 8 0.9DL+1.5EQX 2.24 76.06 0 9 1.2 (DL+LL-EQX) 91.41 2.71 0 10 1.5 (DL-EQX) 3.43 103.37 0 11 0.9DL-1.5EQX 2.01 77.8 0 12 1.2 (DL+LL+EQZ) 90.71 34.58 0 13 1.5 (DL+EQZ) 43.26 102.5 0 14 0.9DL+1.5EQZ 41.85 76.92 0 15 1.2 (DL+LL-EQZ) 90.72 28.98 0 16 1.5 (DL-EQZ) 36.19 102.51 0 17 0.9DL-1.5EQZ 37.6 76.93 Joint
Mzz/Zzz (3) 2.58 30.17 37.7 38.73 34.29 42.88 41.84 2.23 2.79 1.76 1.91 2.4 1.36
1+2+3 109.83 123.08 142.98 117.03 128.41 149.68 121.65 127.52 148.55 120.53 121.61 141.1 115.89
1-2+3 102.83 117.3 135.68 112.55 122.99 142.82 117.63 58.36 62.03 36.83 63.65 68.72 40.69
1-2-3 97.67 56.96 60.28 35.09 54.41 57.06 33.95 53.9 56.45 33.31 59.83 63.92 37.97
1+2-3 104.67 62.74 67.58 39.57 59.83 63.92 37.97 123.06 142.97 117.01 117.79 136.3 113.17
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for Overturning & Sliding:Check against Overturning Stabilize Moment Load Joint O/T Case FOS Result Mmt. (Soil,Pe Load on d, Fdn) Ped 270 F7-C15 0 0 0 0 0 0 0 0 0 0 0 5 1.5 (DL+LL) 624.72 26.6 6 1.2 (DL+LL+EQX) 163.96 624.72 7 1.5 (DL+EQX) 624.72 204.9 8 0.9DL+1.5EQX 624.72 209.63 9 1.2 (DL+LL-EQX) 185.99 624.72 10 1.5 (DL-EQX) 624.72 232.59 11 0.9DL-1.5EQX 624.72 226.3 12 1.2 (DL+LL+EQZ) 224.36 624.72 13 1.5 (DL+EQZ) 624.72 280.69 14 0.9DL+1.5EQZ 624.72 271.29 15 1.2 (DL+LL-EQZ) 188.05 624.72 16 1.5 (DL-EQZ) 624.72 234.83 17 0.9DL-1.5EQZ 624.72 243.75 1056.08 833.6 1021.75 607.42 856.13 1049.92 635.59 844.79 1035.74 621.41 844.94 1035.92 621.59 63.19 8.9 8.04 5.88 7.97 7.21 5.57 6.55 5.92 4.6 7.82 7.08 5.12 SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Check against Sliding Total Hz. Force 13.11 20.52 25.61 25.93 28.75 36.07 32.55 86.42 108.15 103.29 67.62 84.41 89.03 Total FOS for Result Vert. Sliding Load 1120.53 972.21 1097.64 821.42 987.23 1116.42 840.2 979.67 1106.97 830.75 979.77 1107.09 830.87 42.73 23.7 21.43 15.84 17.17 15.48 12.91 5.67 5.12 4.03 7.25 6.56 4.67 SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Check For Shear a) Two Way Shear Limit State Method
d/2
d/2
Critical Section = At distance d/2 from face of column Concrete Grade = Column Details Length = Width = Foundation Details Length = Width = Effective Depth = Percentage Of Steel = 30 500 750 N/mm2 mm mm
3000 3600 425 0.27
mm mm mm %
Punching Load Maximum Load on Column = 704.05 kN Punching Shear,P = 704.052 x (( 3 x 3.6 ) - ( 0.925 x 1.175 )) ( 3 * 3.6 ) P = 633.2 kN
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Shear Resistance Of Concrete (Vc) = vc x bc x d -----Refer to clause no. 31.6.3.1 of IS 456 where vc = ks x tc ks = 0.5 + c -----should not be greater than 1 c = Short Side Of Column Long Side Of Column c = c = ks = c = 500 750 0.67 1
1.37 N/mm2 bc = Appropriate perimeter at distance d/2 Length of critical section = Width of critical section = Perimeter of critical section = Depth Required = 925 1175 4200 mm mm mm
633200 1.37 x4200 = 110.05 mm Shear Resistance = 1.37 x 4200 x 425 / 1000 2445 kN149.68 kN/m2
B) One Way Shear1000 0 1425 425 115.74d
125.86
kN/m2
kN/m2
500 750
3600
500 200 1250 425 3000 825 63.92 kN/m2
142.82
kN/m2 146.83 kN/m2
149.68 147.8
kN/m2 kN/m2
Case = With Stress Increase
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Length at Width at
Length at Width at
At Length Maximum Pressure = 147.797 - 25 x 0.5 - 18 x ( 2 108.3 kN/m2 -- For without critical section = 3000 mm critical section = 1000 mm Shear Force = 108.297 x 3 x 1 = 324.89 kN At Width Maximum Pressure = 125.861 - 25 x 0.5 - 18 x ( 2 86.36 kN/m2 -- For without critical section = 3600 mm critical section = 825 mm Shear Force = 86.361 x 3.6 x 0.825 = 256.49 kN Designed Shear Stress = Corresponding Length = % Ast = Allowable Shear Stress k Increaae In Shear Stress c 324.89 3000 0.27 kN mm
0.5 )Buoynacy Condition With Stress Increse
0.5 )Buoynacy Condition With Stress Increse
= 0.38 N/mm2 ----Refer Table 19 of IS 456 = 1 ---- Refer clause no. 40.2 of IS 456 = Allowed = 1.25 x 0.3804 x 1 N/mm2 0.48 324891 0.4755 x 3000 = 303 mm
= Depth Required =
Design Of Foundation a) Calculation of Reinforcement at Bottom Maximum Pressure = 149.68 -- Without Buoyancy Load Case Pressure due to Soil & Fdn wt = ( 135 + 281.475 ) / ( 3 x 3.6 ) = 38.56 Net causing moment = 111.12 kN/m2 Maximum Projection of fdn = 1.43 m Bending Moment = 111.123 x 1.425 x 1.425 / 2 = 112.82 kN.m Ast = 0.5 x fck x b x d fy Ast = Mini.% of re-bar = Ast = Use Area of bar = Spacing = Provide Spacing = Area Provided = 1146.17 0.2 850 16 200.96 175 175 1148.34 mm2 % mm2 mm dia bars mm2 mm
1 -
1-
(4.6 x Mu ) fck x b x d2
mm2
Provide 16 mm dia Bars @ 175 mm spacing bothways
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
b) Calculation of Reinforcement at Top Reinforcement at top is checked for overburden load on top of foundation since 100% of foundation is not in contact with soil. Wt. Of Soil + Fdn wt. = 416.48 kN Area Load = 416.475 / (3 x 3.6) 38.56 Maxi. Projection of fdn = 1.43 kN/m2 m
Bending Moment = 38.56 x 1.425 x 1.425 / 2 = Ast = 39.15 kN.m 1 1-
0.5 x fck x b x d fy Ast = 387.79 0.1 425 12 113.04 265 265 mm2 %
(4.6 x Mu ) fck x b x d2
Mini % of Re-bar = Ast = Use Area of bar = Spacing = Provide Spacing =
mm2 mm dia bars mm2
mm mm Area Provided = 426.57 mm2 Provide 12 mm dia Bars @ 265 mm spacing bothways
Summary Of Design :Length Of Footing :3000 mm WIdth Of Footing :3600 mm Depth Of Footing :500 mm Reinforcement :At Top :- Provide 12 mm dia Bars @ 265 mm spacing bothways At Bottom :- Provide 16 mm dia Bars @ 175 mm spacing bothways
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
DESIGN OF ISOLATED FOOTING Density Of Concrete = Density Of Soil = Depth Of Foundation = 25 18 2 kN/m3 kN/m m3
FOOTING NO. COLUMN NO.
F7 C17
Net SBC = 104 kN/m2 (As per foundation design basis.) Gross SBC = 104 + 2 x 18 = 140 kN/m (Where increase in SBC is not allowed.) Gross SBC = 104 x 1.25 + 18 x 2 = 166 kN/m2 (Where increase in SBC is allowed.)2
REFER STAAD ANALYSIS FILE SUPPORT REACTION.
FC = FY Length Of Footing L Width Of Footing W Thickness Of Fdn T Width Of Pedestal wp Length Of Pedestal lp Height Of Pedestal Coefficient Of Friction Ground Water Table Ht. = = = = = = = = =L
30 415 3 3.6 0.5 0.75 0.5 0 0.5 0
N/mm2 N/mm2 m m m m m m m
1.43
W
Wp
1.43Z
1.25X
Lp
1.25
Load Calculation for Footing & Soil:Self Wt. Of Footing = 25 x 3 x 3.6 x 0.5 = 135 kN Weight of Soil = [(3 x 3.6) - (0.5 x 0.75)] x (2 - 0.5 ) x 18 = 281.48 kN Self Wt. Of Pedestal = 25 x 0.75 x 0.5 x 0 = 0 kN (Not considered here since it is modelled in STAAD) Weight of Footing + Soil = 135 + 0 + 281.475 = 416.48 kN
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
JOINT 266 F7-C17
INPUT:- INPUT STAAD SUPPORT REACTION (Unit kN - m) LOAD FORCE-X FORCE-Y FORCE-Z MOM-X MOM-Y MOM Z 5 1.5 (DL+LL) -5.42 687.28 -19.74 -24.91 -0.31 8.64 6 1.2 (DL+LL+EQX) -50.29 564.59 -15.33 -19.99 24.62 220.44 7 1.5 (DL+EQX) -62.41 689.67 -19.75 -25.6 30.83 274.72 8 0.9DL+1.5EQX -60.43 421.18 -11.62 -15.39 30.93 271.6 9 1.2 (DL+LL-EQX) 41.63 535.06 -16.25 -19.87 -25.13 -206.62 10 1.5 (DL-EQX) 52.49 652.75 -20.91 -25.45 -31.37 -259.11 11 0.9DL-1.5EQX 54.48 384.27 -12.77 -15.24 -31.26 -262.23 12 1.2 (DL+LL+EQZ) -3.97 498.77 -72.37 -168.03 1.82 5.15 13 1.5 (DL+EQZ) -4.51 607.39 -91.05 -210.65 2.32 5.61 14 0.9DL+1.5EQZ -2.52 338.91 -82.92 -200.44 2.42 2.48 15 1.2 (DL+LL-EQZ) -4.69 600.88 40.79 128.17 -2.32 8.67 16 1.5 (DL-EQZ) -5.41 735.02 50.4 159.6 -2.86 10 17 0.9DL-1.5EQZ -3.43 466.54 58.53 169.81 -2.75 6.88
Check for Maximum and Minimum Pressure at the Base:Area of Footing A = 3 x 3.6 A = 10.8 m2
Section Modulus Zxx = 1/6 x 3 x 3.6 x 3.6 Zxx = 6.48 m3
Section Modulus Zzz = 1/6 x 3.6 x 3 x 3 Zzz = 5.4 m3
Total Vertical Load P = 687.282 + 416.48 = 1103.76 kN P/A = 1103.762 / (3 x 3.6 ) = 102.2 kN/m2
Mxx/Zxx = 24.914 / 6.48 Mxx/Zxx = 3.845 kN/m2
Mzz/Zzz = 8.636 / 5.4 Mzz/Zzz = 1.600 kN/m2
Maxi.Soil Pressure pmax = 102.2 + 3.845 + 1.6 pmax = 107.65 kN/m2 Less Than Allowable Hence O.K. Mini.Soil Pressure pmin = 102.2 - 3.845 - 1.6 pmin = 96.76 kN/m2 > 0 < 140 kN/m2
No Tension at the Base of Footing
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for Overturning:Overturning Moment = Resultant of Mx & Mz = 26.37 kN.m Calculation of Stabilizing Moment Due to External Load = 687.282 x 3 / 2 = 1030.93 kN.m Due to wt. of Pedestral = 0 x 1.5 = 0
kN.m
Due to Self Wt. of Fdn = 135 x 1.5 = 202.5 kN.m Due to Wt. of Soil = 281.475 x 1.5 = 422.22 kN.m Total Stabilizing moment = 1030.93 + 0 + 202.5 + 422.22 = 1655.65 kN.m F.O.S. against Overturning = 1655.65 / 26.37 = 62.79 > 1.2 Hence Safe Check for Sliding:Resultant Shear Force = 20.47 kN
Total Vertical Load = 1103.76 kN F.O.S. against Sliding = 1103.762 x 0.5 / 20.47 = 26.97 > 1.4 Hence Safe
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for All Load Cases:Check for Maxi. & Mini. Pressure at Base of Footing:Load Total P/A Case Load 266 5 1.5 (DL+LL) ### 102.2 F7-C17 6 1.2 (DL+LL+EQX) 981.07 90.84 0 7 1.5 (DL+EQX) 102.42 ### 0 8 0.9DL+1.5EQX 77.56 837.66 0 9 1.2 (DL+LL-EQX) 951.54 88.11 0 10 1.5 (DL-EQX) 99 ### 0 11 0.9DL-1.5EQX 74.14 800.75 0 12 1.2 (DL+LL+EQZ) 915.25 84.75 0 13 1.5 (DL+EQZ) 94.8 ### 0 14 0.9DL+1.5EQZ 69.94 755.39 0 15 1.2 (DL+LL-EQZ) ### 94.2 0 16 1.5 (DL-EQZ) 106.62 1151.5 0 17 0.9DL-1.5EQZ 81.76 883.02 Joint Mxx/Zxx 3.85 3.09 3.96 2.38 3.07 3.93 2.36 25.94 32.51 30.94 19.78 24.63 26.21 Mzz/Zzz 1.6 40.83 50.88 50.3 38.27 47.99 48.57 0.96 1.04 0.46 1.61 1.86 1.28 pmax 107.65 134.76 157.26 130.24 129.45 150.92 125.07 111.65 128.35 101.34 115.59 133.11 109.25 pall 140 166 166 166 166 166 166 166 166 166 166 166 166 pmin 96.76 46.92 47.59 24.89 46.77 47.09 23.22 57.85 61.26 38.55 72.81 80.14 54.28 Result SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Summary of Bearing Pressure Without Stress Increase:With Stress Increase:pmax = pmax = 157.26 kN/m2 107.65 kN/m2 pmin = 96.76 kN/m2 pmin = 23.22 kN/m2
Load P/A Mxx/Zxx Case (1) (2) 266 5 1.5 (DL+LL) 102.2 3.85 F7-C17 6 1.2 (DL+LL+EQX) 90.84 3.09 0 7 1.5 (DL+EQX) 3.96 102.42 0 8 0.9DL+1.5EQX 2.38 77.56 0 9 1.2 (DL+LL-EQX) 88.11 3.07 0 10 1.5 (DL-EQX) 3.93 99 0 11 0.9DL-1.5EQX 2.36 74.14 0 12 1.2 (DL+LL+EQZ) 84.75 25.94 0 13 1.5 (DL+EQZ) 32.51 94.8 0 14 0.9DL+1.5EQZ 30.94 69.94 0 15 1.2 (DL+LL-EQZ) 94.2 19.78 0 16 1.5 (DL-EQZ) 24.63 106.62 0 17 0.9DL-1.5EQZ 26.21 81.76 Joint
Mzz/Zzz (3) 1.6 40.83 50.88 50.3 38.27 47.99 48.57 0.96 1.04 0.46 1.61 1.86 1.28
1+2+3 107.65 134.76 157.26 130.24 129.45 150.92 125.07 111.65 128.35 101.34 115.59 133.11 109.25
1-2+3 99.95 128.58 149.34 125.48 123.31 143.06 120.35 59.77 63.33 39.46 76.03 83.85 56.83
1-2-3 96.75 46.92 47.58 24.88 46.77 47.08 23.21 57.85 61.25 38.54 72.81 80.13 54.27
1+2-3 104.45 53.1 55.5 29.64 52.91 54.94 27.93 109.73 126.27 100.42 112.37 129.39 106.69
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for Overturning & Sliding:Check against Overturning Stabilize Moment Load Joint O/T Case FOS Result Mmt. (Soil,Pe Load on d, Fdn) Ped 266 F7-C17 0 0 0 0 0 0 0 0 0 0 0 5 1.5 (DL+LL) 624.72 26.37 6 1.2 (DL+LL+EQX) 221.34 624.72 7 1.5 (DL+EQX) 624.72 275.91 8 0.9DL+1.5EQX 624.72 272.03 9 1.2 (DL+LL-EQX) 207.58 624.72 10 1.5 (DL-EQX) 624.72 260.36 11 0.9DL-1.5EQX 624.72 262.68 12 1.2 (DL+LL+EQZ) 168.11 624.72 13 1.5 (DL+EQZ) 624.72 210.73 14 0.9DL+1.5EQZ 624.72 200.46 15 1.2 (DL+LL-EQZ) 128.46 624.72 16 1.5 (DL-EQZ) 624.72 159.91 17 0.9DL-1.5EQZ 624.72 169.95 1030.93 846.89 1034.5 631.78 802.59 979.13 576.41 748.17 911.1 508.37 901.32 1102.54 699.81 62.79 6.65 6.02 4.62 6.88 6.17 4.58 8.17 7.29 5.66 11.88 10.81 7.8 SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Check against Sliding Total Hz. Force 20.46 52.58 65.46 61.53 44.69 56.5 55.95 72.48 91.16 82.96 41.06 50.69 58.63 Total FOS for Result Vert. Sliding Load 1103.76 981.07 1106.15 837.66 951.54 1069.23 800.75 915.25 1023.87 755.39 1017.36 1151.5 883.02 26.97 9.33 8.45 6.81 10.65 9.47 7.16 6.32 5.62 4.56 12.39 11.36 7.54 SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Check For Shear a) Two Way Shear Limit State Method
d/2
d/2
Critical Section = At distance d/2 from face of column Concrete Grade = Column Details Length = Width = Foundation Details Length = Width = Effective Depth = Percentage Of Steel = 30 500 750 N/mm2 mm mm
3000 3600 425 0.3
mm mm mm %
Punching Load Maximum Load on Column = 735.02 kN Punching Shear,P = 735.024 x (( 3 x 3.6 ) - ( 0.925 x 1.175 )) ( 3 * 3.6 ) P = 661.06 kN
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Shear Resistance Of Concrete (Vc) = vc x bc x d -----Refer to clause no. 31.6.3.1 of IS 456 where vc = ks x tc ks = 0.5 + c -----should not be greater than 1 c = Short Side Of Column Long Side Of Column c = c = ks = c = 500 750 0.67 1
1.37 N/mm2 bc = Appropriate perimeter at distance d/2 Length of critical section = Width of critical section = Perimeter of critical section = Depth Required = 925 1175 4200 mm mm mm
661060 1.37 x4200 = 114.89 mm Shear Resistance = 1.37 x 4200 x 425 / 1000 2445 kN157.26 kN/m2
B) One Way Shear1000 0 1425 425 116.98d
129
kN/m2
kN/m2
500 750
3600
500 200 1250 425 3000 825 55.5 kN/m2
149.34
kN/m2 153.96 kN/m2
157.26 155.08
kN/m2 kN/m2
Case = With Stress Increase
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Length at Width at
Length at Width at
At Length Maximum Pressure = 155.083 - 25 x 0.5 - 18 x ( 2 115.58 kN/m2 -- For without critical section = 3000 mm critical section = 1000 mm Shear Force = 115.583 x 3 x 1 = 346.75 kN At Width Maximum Pressure = 128.995 - 25 x 0.5 - 18 x ( 2 89.5 kN/m2 -- For without critical section = 3600 mm critical section = 825 mm Shear Force = 89.495 x 3.6 x 0.825 = 265.8 kN Designed Shear Stress = Corresponding Length = % Ast = Allowable Shear Stress k Increaae In Shear Stress c 346.75 3000 0.3 kN mm
0.5 )Buoynacy Condition With Stress Increse
0.5 )Buoynacy Condition With Stress Increse
= 0.4 N/mm2 ----Refer Table 19 of IS 456 = 1 ---- Refer clause no. 40.2 of IS 456 = Allowed = 1.25 x 0.396 x 1 N/mm2 0.5 346749 0.495 x 3000 = 309 mm
= Depth Required =
Design Of Foundation a) Calculation of Reinforcement at Bottom Maximum Pressure = 157.26 -- Without Buoyancy Load Case Pressure due to Soil & Fdn wt = ( 135 + 281.475 ) / ( 3 x 3.6 ) = 38.56 Net causing moment = 118.7 kN/m2 Maximum Projection of fdn = 1.43 m Bending Moment = 118.701 x 1.425 x 1.425 / 2 = 120.52 kN.m Ast = 0.5 x fck x b x d fy Ast = Mini.% of re-bar = Ast = Use Area of bar = Spacing = Provide Spacing = Area Provided = 1227.79 0.2 850 16 200.96 163 160 1256 mm2 % mm2 mm dia bars mm2 mm
1 -
1-
(4.6 x Mu ) fck x b x d2
mm2
Provide 16 mm dia Bars @ 160 mm spacing bothways
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
b) Calculation of Reinforcement at Top Reinforcement at top is checked for overburden load on top of foundation since 100% of foundation is not in contact with soil. Wt. Of Soil + Fdn wt. = 416.48 kN Area Load = 416.475 / (3 x 3.6) 38.56 Maxi. Projection of fdn = 1.43 kN/m2 m
Bending Moment = 38.56 x 1.425 x 1.425 / 2 = Ast = 39.15 kN.m 1 1-
0.5 x fck x b x d fy Ast = 387.79 0.1 425 12 113.04 265 265 mm2 %
(4.6 x Mu ) fck x b x d2
Mini % of Re-bar = Ast = Use Area of bar = Spacing = Provide Spacing =
mm2 mm dia bars mm2
mm mm Area Provided = 426.57 mm2 Provide 12 mm dia Bars @ 265 mm spacing bothways
Summary Of Design :Length Of Footing :3000 mm WIdth Of Footing :3600 mm Depth Of Footing :500 mm Reinforcement :At Top :- Provide 12 mm dia Bars @ 265 mm spacing bothways At Bottom :- Provide 16 mm dia Bars @ 160 mm spacing bothways
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
DESIGN OF ISOLATED FOOTING Density Of Concrete = Density Of Soil = Depth Of Foundation = 25 18 2 kN/m3 kN/m m3
FOOTING NO. COLUMN NO.
F8 C16
Net SBC = 104 kN/m2 (As per foundation design basis.) Gross SBC = 104 + 2 x 18 = 140 kN/m (Where increase in SBC is not allowed.) Gross SBC = 104 x 1.25 + 18 x 2 = 166 kN/m2 (Where increase in SBC is allowed.)2
REFER STAAD ANALYSIS FILE SUPPORT REACTION.
FC = FY Length Of Footing L Width Of Footing W Thickness Of Fdn T Width Of Pedestal wp Length Of Pedestal lp Height Of Pedestal Coefficient Of Friction Ground Water Table Ht. = = = = = = = = =L
30 415 3 4.5 0.6 0.75 0.5 0 0.5 0
N/mm2 N/mm2 m m m m m m m
1.88
W
Wp
1.88Z
1.25X
Lp
1.25
Load Calculation for Footing & Soil:Self Wt. Of Footing = 25 x 3 x 4.5 x 0.6 = 202.5 kN Weight of Soil = [(3 x 4.5) - (0.5 x 0.75)] x (2 - 0.6 ) x 18 = 330.75 kN Self Wt. Of Pedestal = 25 x 0.75 x 0.5 x 0 = 0 kN (Not considered here since it is modelled in STAAD) Weight of Footing + Soil = 202.5 + 0 + 330.75 = 533.25 kN
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
JOINT 265 F8-C16
INPUT:- INPUT STAAD SUPPORT REACTION (Unit kN - m) LOAD FORCE-X FORCE-Y FORCE-Z MOM-X 5 1.5 (DL+LL) -4.95 886.62 13.62 10.25 6 1.2 (DL+LL+EQX) -49.19 721.27 11.31 9.18 7 1.5 (DL+EQX) -60.97 856.64 14.12 11.49 8 0.9DL+1.5EQX -59.2 519.97 8.68 7.38 9 1.2 (DL+LL-EQX) 41.26 697.33 10.49 7.22 10 1.5 (DL-EQX) 52.09 826.72 13.11 9.05 11 0.9DL-1.5EQX 53.86 490.05 7.66 4.94 12 1.2 (DL+LL+EQZ) -4.03 708.26 -99.15 -287 13 1.5 (DL+EQZ) -4.53 840.38 -123.95 -358.73 14 0.9DL+1.5EQZ -2.75 503.71 -129.4 -362.84 15 1.2 (DL+LL-EQZ) -3.9 710.33 120.95 303.4 16 1.5 (DL-EQZ) -4.36 842.97 151.18 379.27 17 0.9DL-1.5EQZ -2.58 506.3 145.73 375.16
MOM-Y 2.62 7.28 8.87 7.92 -3.1 -4.1 -5.06 -0.65 -1.04 -1.99 4.83 5.8 4.85
MOM Z 16.02 251.21 312.41 306.65 -225.59 -283.59 -289.35 13.04 14.69 8.93 12.59 14.13 8.37
Check for Maximum and Minimum Pressure at the Base:Area of Footing A = 3 x 4.5 A = 13.5 m2
Section Modulus Zxx = 1/6 x 3 x 4.5 x 4.5 Zxx = 10.13 m3
Section Modulus Zzz = 1/6 x 4.5 x 3 x 3 Zzz = 6.75 m3
Total Vertical Load P = 886.62 + 533.25 = 1419.87 kN P/A = 1419.87 / (3 x 4.5 ) = 105.18 kN/m2
Mxx/Zxx = 10.251 / 10.125 Mxx/Zxx = 1.013 kN/m2
Mzz/Zzz = 16.016 / 6.75 Mzz/Zzz = 2.373 kN/m2
Maxi.Soil Pressure pmax = 105.176 + 1.013 + 2.373 pmax = 108.57 kN/m2 Less Than Allowable Hence O.K. Mini.Soil Pressure pmin = 105.176 - 1.013 - 2.373 pmin = 101.79 kN/m2 No Tension at the Base of Footing > 0 < 140 kN/m2
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for Overturning:Overturning Moment = Resultant of Mx & Mz = 19.02 kN.m Calculation of Stabilizing Moment Due to External Load = 886.62 x 3 / 2 = 1329.93 kN.m Due to wt. of Pedestral = 0 x 1.5 = 0
kN.m
Due to Self Wt. of Fdn = 202.5 x 1.5 = 303.75 kN.m Due to Wt. of Soil = 330.75 x 1.5 = 496.13 kN.m Total Stabilizing moment = 1329.93 + 0 + 303.75 + 496.13 = 2129.81 kN.m F.O.S. against Overturning = 2129.81 / 19.02 = 111.98 > 1.2 Hence Safe Check for Sliding:Resultant Shear Force = 14.5 kN
Total Vertical Load = 1419.87 kN F.O.S. against Sliding = 1419.87 x 0.5 / 14.5 = 48.97 > 1.4 Hence Safe
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for All Load Cases:Check for Maxi. & Mini. Pressure at Base of Footing:Load Total P/A Case Load 265 5 1.5 (DL+LL) 105.18 ### F8-C16 6 1.2 (DL+LL+EQX) ### 92.93 0 7 1.5 (DL+EQX) 102.95 ### 0 8 0.9DL+1.5EQX 78.02 ### 0 9 1.2 (DL+LL-EQX) ### 91.15 0 10 1.5 (DL-EQX) 100.74 ### 0 11 0.9DL-1.5EQX 75.8 1023.3 0 12 1.2 (DL+LL+EQZ) ### 91.96 0 13 1.5 (DL+EQZ) 101.75 ### 0 14 0.9DL+1.5EQZ 76.81 ### 0 15 1.2 (DL+LL-EQZ) ### 92.12 0 16 1.5 (DL-EQZ) 101.94 ### 0 17 0.9DL-1.5EQZ 77 ### Joint Mxx/Zxx 1.02 0.91 1.14 0.73 0.72 0.9 0.49 28.35 35.43 35.84 29.97 37.46 37.06 Mzz/Zzz 2.38 37.22 46.29 45.43 33.42 42.02 42.87 1.94 2.18 1.33 1.87 2.1 1.24 pmax 108.58 131.06 150.38 124.18 125.29 143.66 119.16 122.25 139.36 113.98 123.96 141.5 115.3 pall 140 166 166 166 166 166 166 166 166 166 166 166 166 pmin 101.78 54.8 55.53 31.86 57.02 57.82 32.44 61.68 64.15 39.65 60.28 62.39 38.71 Result SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Summary of Bearing Pressure Without Stress Increase:With Stress Increase:pmax = pmax = 150.38 kN/m2 108.58 kN/m2 pmin = 101.78 kN/m2 pmin = 31.86 kN/m2
Load P/A Mxx/Zxx Case (1) (2) 265 5 1.5 (DL+LL) 105.18 1.02 F8-C16 6 1.2 (DL+LL+EQX) 92.93 0.91 0 7 1.5 (DL+EQX) 1.14 102.95 0 8 0.9DL+1.5EQX 0.73 78.02 0 9 1.2 (DL+LL-EQX) 91.15 0.72 0 10 1.5 (DL-EQX) 0.9 100.74 0 11 0.9DL-1.5EQX 0.49 75.8 0 12 1.2 (DL+LL+EQZ) 91.96 28.35 0 13 1.5 (DL+EQZ) 35.43 101.75 0 14 0.9DL+1.5EQZ 35.84 76.81 0 15 1.2 (DL+LL-EQZ) 92.12 29.97 0 16 1.5 (DL-EQZ) 37.46 101.94 0 17 0.9DL-1.5EQZ 37.06 77 Joint
Mzz/Zzz (3) 2.38 37.22 46.29 45.43 33.42 42.02 42.87 1.94 2.18 1.33 1.87 2.1 1.24
1+2+3 108.58 131.06 150.39 124.18 125.29 143.66 119.16 122.25 139.36 113.98 123.96 141.5 115.3
1-2+3 106.54 129.24 148.11 122.72 123.85 141.86 118.18 65.55 68.5 42.3 64.02 66.58 41.18
1-2-3 101.78 54.8 55.53 31.86 57.01 57.82 32.44 61.67 64.14 39.64 60.28 62.38 38.7
1+2-3 103.82 56.62 57.81 33.32 58.45 59.62 33.42 118.37 135 111.32 120.22 137.3 112.82
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Check for Overturning & Sliding:Check against Overturning Stabilize Moment Load Joint O/T Case FOS Result Mmt. (Soil,Pe Load on d, Fdn) Ped 265 F8-C16 0 0 0 0 0 0 0 0 0 0 0 5 1.5 (DL+LL) 799.88 19.02 6 1.2 (DL+LL+EQX) 251.38 799.88 7 1.5 (DL+EQX) 799.88 312.62 8 0.9DL+1.5EQX 799.88 306.73 9 1.2 (DL+LL-EQX) 225.7 799.88 10 1.5 (DL-EQX) 799.88 283.73 11 0.9DL-1.5EQX 799.88 289.39 12 1.2 (DL+LL+EQZ) 287.29 799.88 13 1.5 (DL+EQZ) 799.88 359.03 14 0.9DL+1.5EQZ 799.88 362.94 15 1.2 (DL+LL-EQZ) 303.66 799.88 16 1.5 (DL-EQZ) 799.88 379.53 17 0.9DL-1.5EQZ 799.88 375.25 1329.93 1081.9 1284.96 779.96 1045.99 1240.08 735.07 1062.39 1260.57 755.57 1065.5 1264.47 759.46 112.01 7.49 6.67 5.16 8.18 7.19 5.31 6.49 5.74 4.29 6.15 5.44 4.16 SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Check against Sliding Total Hz. Force 14.5 50.47 62.59 59.83 42.58 53.71 54.41 99.23 124.03 129.43 121.01 151.24 145.76 Total FOS for Result Vert. Sliding Load 1419.87 1254.52 1389.89 1053.22 1230.58 1359.97 1023.3 1241.51 1373.63 1036.96 1243.58 1376.22 1039.55 48.98 12.43 11.11 8.81 14.46 12.67 9.41 6.26 5.54 4.01 5.14 4.55 3.57 SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE SAFE
Check For Shear a) Two Way Shear Limit State Method
d/2
d/2
Critical Section = At distance d/2 from face of column Concrete Grade = Column Details Length = Width = Foundation Details Length = Width = Effective Depth = Percentage Of Steel = 30 500 750 N/mm2 mm mm
3000 4500 525 0.31
mm mm mm %
Punching Load Maximum Load on Column = 886.62 kN Punching Shear,P = 886.62 x (( 3 x 4.5 ) - ( 1.025 x 1.275 )) ( 3 * 4.5 ) P = 800.8 kN
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Shear Resistance Of Concrete (Vc) = vc x bc x d -----Refer to clause no. 31.6.3.1 of IS 456 where vc = ks x tc ks = 0.5 + c -----should not be greater than 1 c = Short Side Of Column Long Side Of Column c = c = ks = c = 500 750 0.67 1
1.37 N/mm2 bc = Appropriate perimeter at distance d/2 Length of critical section = Width of critical section = Perimeter of critical section = Depth Required = 1025 1275 4600 mm mm mm
800800 1.37 x4600 = 127.07 mm Shear Resistance = 1.37 x 4600 x 525 / 1000 3308 kN150.39 kN/m2
B) One Way Shear1350 0 1875 525 111.81d
122.61
kN/m2
kN/m2
600 750
4500
500 200 1250 525 3000 725 57.81 kN/m2
148.11
kN/m2 149.44 kN/m2
150.39 149.83
kN/m2 kN/m2
Case = With Stress Increase
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
Length at Width at
Length at Width at
At Length Maximum Pressure = 149.834 - 25 x 0.6 - 18 x ( 2 109.63 kN/m2 -- For without critical section = 3000 mm critical section = 1350 mm Shear Force = 109.634 x 3 x 1.35 = 444.02 kN At Width Maximum Pressure = 122.611 - 25 x 0.6 - 18 x ( 2 82.41 kN/m2 -- For without critical section = 4500 mm critical section = 725 mm Shear Force = 82.411 x 4.5 x 0.725 = 268.87 kN Designed Shear Stress = Corresponding Length = % Ast = Allowable Shear Stress k Increaae In Shear Stress c 444.02 4500 0.31 kN mm
0.6 )Buoynacy Condition With Stress Increse
0.6 )Buoynacy Condition With Stress Increse
= 0.4 N/mm2 ----Refer Table 19 of IS 456 = 1 ---- Refer clause no. 40.2 of IS 456 = Allowed = 1.25 x 0.4012 x 1 N/mm2 0.5 444018 0.5015 x 4500 = 272 mm
= Depth Required =
Design Of Foundation a) Calculation of Reinforcement at Bottom Maximum Pressure = 150.39 -- Without Buoyancy Load Case Pressure due to Soil & Fdn wt = ( 202.5 + 330.75 ) / ( 3 x 4.5 ) = 39.5 Net causing moment = 110.89 kN/m2 Maximum Projection of fdn = 1.88 m Bending Moment = 110.885 x 1.875 x 1.875 / 2 = 194.92 kN.m Ast = 0.5 x fck x b x d fy Ast = Mini.% of re-bar = Ast = Use Area of bar = Spacing = Provide Spacing = Area Provided = 1611.7 0.2 1050 20 314 194 190 1652.63 mm2 % mm2 mm dia bars mm2 mm
1 -
1-
(4.6 x Mu ) fck x b x d2
mm2
Provide 20 mm dia Bars @ 190 mm spacing bothways
JYOTI STRUCTURES LTD. MUMBAI
JOB NO. CUSTOMER DESCRIPTION
GOVT. OF J&K POWER DEPT. SUB STATION ALUSTENG CONTROL ROOM BLDG.
DATE DESIGNED BY CHECKED BY
4-Jul-2009 P.C.K S.A.G
b) Calculation of Reinforcement at Top Reinforcement at top is checked for overburden load on top of foundation since 100% of foundation is not in contact with soil. Wt. Of Soil + Fdn wt. = 533.25 kN Area Load = 533.25 / (3 x 4.5) 39.5 Maxi. Projection of fdn = 1.88 kN/m2 m
Bending Moment = 39.5 x 1.875 x 1.875 / 2 = Ast = 69.43 kN.m 1 1-
0.5 x fck x b x d fy Ast = 557.91 0.1 525 12 113.04 202 200 mm2 %
(4.6 x Mu ) fck x b x d2
Mini % of Re-bar = Ast = Use Area of bar = Spacing = Provide Spacing =
mm2 mm dia bars mm2
mm mm mm2 Area Provided = 565.2 Provide 12 mm dia Bars @ 200 mm spacing bothways
Summary Of Design :Length Of Footing :3000 mm WIdth Of Footing :4500 mm Depth Of Footing :600 mm Reinforcement :At Top :- Provide 12 mm dia Bars @ 200 mm spacing bothways At Bottom :- Provide 20 mm dia Bars @ 190 mm spacing bothways
