4 LOAD CALCULATION
Pipe Load
Load Calculation for 2", 6", 12" & 16" diameter pipe (Pipe weight + Pipe filled with oil)
As per the load data obtained from the piping input, the loads for the pipes are as tabulated below:
Pipe Dia (inches)
No of Pipes
Weight of Pipe (Kg/m)
Weight of oil
(Kg/m)
Weight of
Pipe x Nos
(Kg/m)
Weight of water x
Nos (Kg/m)
Weight of water +
Weight of Pipe
(Kg/m)
Total weight (kg/m)
2" 1 7.47 2.53 7.47 2.53 10.00 10
6" 2 42.50 17.50 85 35 60.00 120
12" 1 73.80 77.20 73.8 77.2 151.00 151
16" 4 93.10 146.90 372.4 587.6 240.00 960
216.87 244.13 538.67 702.33 461.00 1241.00
Total =1241.00 Kg/m 12.4 KN/m
14
Fig 4.1
Fig 4.1 shows The pipe bridge is analysed using a structural software program staad pro. Analysis has been carried out on the structural model considering all loads acting over the structure. Analysed for various load combinations as per code
15
Fig 4.2 The nodes numbers of the pipe rack
16
Fig 4.3 The beam numbers of the pipe rack
17
Fig 4.4 The top plan view of the pipe rack
Fig 4.5 The view of pipe rack
18
Fig 4.6 Shows the Grid 1 and Grid 2 of the pipe rack
19
Fig 4.7 The vertical pipe load of the pipe rack
20
WIND LOAD CALCULATIONS AS PER IS 875-3
Site wind speed, Vs = Vb x Sa x Sd x Ss x Sp
Site wind speed, Vs = Vb x Sa x Sd x Ss x Sp =33.5
Site wind speed, Vs = Vb x Sa x Sd x Ss x Sp =2.75
Site wind speed, Vs = Vb x Sa x Sd x Ss x Sp =1+0.001*ΔS
Site wind speed, Vs = Vb x Sa x Sd x Ss x Sp =1.00275
Site wind speed, Vs = Vb x Sa x Sd x Ss x Sp =1
Site wind speed, Vs = Vb x Sa x Sd x Ss x Sp =1
Site wind speed, Vs = Vb x Sa x Sd x Ss x Sp = 1
Site wind speed, Vs = Vb x Sa x Sd x Ss x Sp =33.592125
Site wind speed, Vs = Vb x Sa x Sd x Ss x Sp
Effective heightHe =6.4
Terrain and building factor, Sb =1.6864
Effective wind speed, Ve = Vs x Sb =56.6497596
Dynamic pressure, qs
Dynamic pressure, qs = 0.613 x Ve^2 =1.96723669605827
Size effect factor, Ca =0.94
Net pressure coefficient (Cp) is shown in the below sections =1
Width of the building, w =4.2
Height of building, h =8
Length of building, l =30.06
Wind Pressure, Pe = qs x Cp x Ca =1.85kN/sqm
21
Wind load calculation for the second frame in grid 1&2 - (X - Direction)
F= force acting in a direction specified
Cf = Force coefficient 1.7
Ae = Effective frontal area
Pd = Design wind pressure
Wind load applied over column as udl = 0.975 kN/m
Wind load applied over Beam 1 LVL as udl = 0.80 kN/m
Wind load applied over Beam 2 & 3 LVL as udl = 0.31 kN/m
Wind load applied over Bracing as nodal load (1B) = 0.81 kN
Wind load applied over Bracing as nodal load (2B) = 0.58 kN
Wind load for bracing applied as nodal load (2B) = 1.15 kN
Fig 4.8 The wind load applied on the grid 1 and 2
22
Wind Load applied in (Z - Direction) 90 Degree
Exposed Area for
Column = 0.32 x 8 x 3 = 7.68 Sqm
Beam (2-3) = 0.254 x 18.55 x 1 = 4.71 Sqm
Tie = 0.09 x 18.55 x1 = 1.67 Sqm
Truss = (0.09 x 3.06 x 8) + (.09*2*7) + (3.79*0.1*2) = 4.22 Sqm
24.42 Sqm
Total Area = 240.48 Sqm
Solidity Ratio Φ = Exposed area = 0.1015
Total Area Cf 1.9
Fig 4.9 The wind load applied in (Z-degree)
23
Wind load calculation for the frame in grid A - (Z - Direction)
Wind load applied over column = 1.090 kN/m
Wind load applied over Beam (1-2) as udl = 0.89 kN/m
Wind load applied over Tie = 0.35 kN/m
Wind load applied over Bracing as nodal load = 0.48 kN
Wind load for bracing applied as nodal load @ 2 points = 0.97 kN
Wind load for bracing applied as nodal load for stub = 0.35 kN
Fig 4.10 The wind load for the frame A in z-direction
24
Wind load calculation for the second frame in grid B - (Z - Direction)
Wind load applied over column = 1.090 kN/m
Wind load applied over Beam (1-2) as udl = 0.89 kN/m
Wind load applied over Tie = 0.35 kN/m
Wind load applied over Bracing as nodal load = 0.48 kN
Wind load for bracing applied as nodal load @ 2 points = 0.97 kN
Wind load for bracing applied as nodal load for stub = 0.35 kN
Fig 4.11 The wind load for the frame B in z-direction
25
5 DESIGN OF BASE PLATE
LOADING
Maximum compression = 360.01 KN
Maximum tension = 187.67 KN
Base Plate details
Length L = 625
Width B = 450
Concrete
Grade of concrete fck = 35 N/mm2
Permissible stress in bending comp. = 11.5 N/mm2
Permissible bearing stress = 8.75 N/mm2 Ref:- 0.25fck
Permissible bond stress in tension = 2.37 N/mm2
modular ratio = 8.116
Bolt data
Dia of bolt Φ = 27 mm
Total no of bolts N = 4 nos
Permissible Axial Stress = 240 N/mm2
Permissible shear stress = 160 N/mm2
Check for compressive stress in concrete
σc= P/(LxB)
= 360.008x1000/(625x450) = 1.920042667 < 8.75
SAFE
26
Design for tension
Maximum tension = 187.671 KN
No of bolts taking tension = 4
Tension per bolt = 70.376625 KN
Design moment M = WL/4
= 70.38x0.225/4
= 3.96 KNm
Allowable bending stress σbc = 165 N/mm2
treq = 6M/(bxσbc)
= (6x3.96x1000000)/(150x165)
= 27.06193215 mm
Design for compression
Maximum compression P = 360.008 KN
Base pressure = P/A
= 1.92 N/mm2
27
Design bending moment M = wL2/8
= 12150.27 Nmm/mm
treq = 6M/(bxσbc)
= (6x12150.27)/(1x165)
= 21.01970504 mm
Provide 30mm thick base plate.
Design of bolts subjected to shear and tension :
Input :
Actual tension in bolts T = 187.67 kN
Actual shear in bolts Fx = 46.073 kN
Fz = 68.352 kN
V = 82.43 kN
Number of bolts resisting tension Nt = 4
Number of bolts resisting shear Ns = 4
Actual tension/bolt =187.67/4 = 56.30 kN
Actual shear/bolt =82.43/4 = 30.91 kN
Diameter of bolt D = 27 mm
Number of bolts provided n = 4
Permissible tensile stress stf = 240 N/mm2
Permissible shear stress tvf = 160 N/mm2
Calculations :
Actual tensile stress = T/(n*PI()*D^2/4*0.8)
Only 80% of the bolt area taken on conservative side
stf,cal =56.3x1000(3.14/4x20^2x0.8) = 122.9 N/mm2
Actual shear stress= V/(n*PI()*D^2/4*0.8)
28
tvf,cal =30.91x1000/(3.14*27^2/4x0.8) = 67.5 N/mm2
Combined stress ratio= stf,cal/stf+ tvf,cal/tvf = 122.9/(240)+67.5/(160)
= 0.93
Allowable stress ratio = 1.4 SAFE
Calculation of embedment length :
Grade of concrete fck = 35 N/mm2
Permissible bond stress tbd = 0.4√fcu N/mm2
= 2.37 N/mm2
Refering clause 3.12.8.4 of BS 8110-1
Tension per bolt, Tb = = 56.30 kN
Embedment length req =Tb/(tbd*PI()*D*0.8) = 56.3*1000/(2.37*3.14*27*0.8) = 351 mm
Embedment length provided = 351 mm
29
6 DESIGN OF PEDESTAL
Pedestal Mark
B
x
D
Design data
Column Size
Width, B = 600 mm
Depth, D = 775 mm
cover = 40 mm
Assuming dia of bar = 16 mm
Assuming dia of link = 8 mm
fcu = 35 N/Sqmm
fy = 460 N/Sqmm
b' = 544 mm
d' = 719 mm
b' / B = = 0.907
d' / D = 0.928
30
Effective length calculation
Unsupported length, about depth = 1.80 m
Unsupported length, about width = 1.80 m
Effective length factor about depth = 2
Effective length factor about width = 2
Effective length of column about depth, Lex 2*1.8 = 3.60 m
Effective length of column about width, Lez 2*1.8 3.60 m
Forces on columns
Refer staad output of member end forces
Axial load on column, N = 360.01 kN
Force, Fx = 46.03 kN
Force, Fz = 68.35 kN
Moment about depth
Initial end moment, M2x = 123.03 kNm
Smaller initial end moment, M1x = 0.00 kNm
Moment about width
Initial end moment, M2z = 82.86 kNm
Smaller initial end moment, M1z = 0.00 kNm
Slenderness check
Slenderness about depth, Lex / D = 4.65
Slenderness about width, Lez / B = 6.00
31
Calculation of Nuz and K
Balance load, Nb = 0.25 x fcu x B x D = 4068.75 kN
Assuming ptmin = 0.4%, Asc = 0.4 x B x D / 100 = 1860 Sq
Nuz, (0.45 x fcu x Ac) +(0.95 x Asc x fy) 8136.57 kN
Reduction factor , K = (Nuz - N)/ (Nuz- Nb) = 1.912
Hence K is limited to one K = 1 (As per Cl 3.8.3.1 of BS 8110:Part 1:1997) 1
Additonal moments
About major axis = aux, K x D x (Lex/D )^2/20000.00 mm
Max = N*aux = 0.00 kNm
Mx = M2x + Max = 123.03 kNm
About minor axis = auz = K x B x (Lez/B )^2/2000 0.00 mm
Maz = N*auz = 0.00 kNm
Mz = M2z + Maz = 82.86 kNm
Ratio = N / (B x D x Fcu) = 0.022
(As per Table 3.22 of BS 8110:Part 1:1997)
Co-efficient Beta, β = 0.973455631
Mx / d' = 171117.7
Mz / b' = 152311.8
As Mx / d' >Mz/b'
Mx' = Mx + Mz x β x d' / b' = 229.64 kNm
32
Section design - Ratios for chart entry
Axial load ratio = Nratio = N / (B x D) = 0.77
For design we have considered Maximum Moment about one axis
Mz ratio = Mz' / (B x D^2) = 0.64
d'/D = 0.93
Actual Steel Percentage required, P(req) = 0.80 %
Area of Reinforcement required Ast(reqd) = 3720 Sqmm
Area of Reinfocement required Ast reqd. (for each face) = 1860 Sqmm
Since Limit state stress in reinforcing steel is taken as 0.87fy in charts
as against 0.95fy inEquation 1 of cl. 3.4.4.5,the modification in
reinforcement area calculation is taken as below
Actual Ast reqd. = 1860*0.87/0.95 =1703 Sqmm
Total area of Reinforcement = 3407 Sqmm
Total area of Reinforcement Provided
Provide 6 nos of 20 dia bars = 3768 Sqmm
6 nos of 20 dia bars Hence o.k
Ast provided in each faces 6 -16 + 6 -16 dia bars. = 3768 Sqmm
33
7 Design of Combined Foundation "F2"
LC 30
Net SBC SBCnet 106.25 kN/m2
Factor for inc in BC Fbc 1
Joint No 5 7
X
PEDESTAL MARK
Col Mark SUM 1 2 cx1
Z wrt 1 0 4.2 z z b
X wrt 1 0 0 cx2
P (kN) -84.64 360.01 Cz1 x Cz2
Mx (kNm) 0 0.00 0.00
Hz (kN) -129.053 -60.70 -68.35
Mz (kNm) 0 0.00 0.00
Hx (kN) 55.364 27.61 27.75
Pedestal Size
lZ 0.6 0.6
lX 0.775 0.78
Pped 11.04 11.04
Depth of foundation from the level of point of application of forces
dforc 1.3 1.3
Depth of foundation below ground level (FGL)
Depth of foundation below Natural Ground Level (NGL)
34
Unit Weight of soil
Projections of Footing (from centreline of column)
LHS Cz1 1.725
RHS Cz2 1.725
Bottom Cx1 1
Top Cx2 1
Length of footing l 7.650 m
Width of footing b 2.000 m
Depth of footing d 0.350 m
Calculations :
Col Mark SUM 1 2
xcor 1.725 5.925
ycor 1 1
Axial Load including weight of Pedestal
( Pconc = P + Pped )
Pconc 297 -73.59 371.05
Moment at base of foundation due to Horizontal Forces
(Mxh = Hz * dforc ) (Mzh = Hx * dforc )
Mxh -167.7689 -78.9113 -88.8576
Mzh 71.97 35.8943 36.0789
Moments due to Conc. Moments & Horizontal Forces
(Myc = My + Myh ) (Mxc = Mx + Mxh )
Mxc -168 -78.9113 -88.8576
Mzc 72 35.8943 36.0789
35
Gross SBC SBCg=Fbc * SBCnet + gs * dfngl= 125.25 kN/m2 126k N/m2
Total Axial Load incl wt of pedestal (∑Pconc ) ∑P 297.4595 kN
Area of foundation ( Provided ) A l * b 15.3 m2
Load due to soil Psoil gs*(df - d)*(A - S(lx*ly)) 177.47 kN
Weight of foundation Fbase A*d*25 133.875 kN
Total Vertical Load Pv SP + Psoil + Fbase 608.80 kN
CG of load system from bottom left corner of footing Moments due to ∑concS(∑conc Xcor) 2071.534988 S(Pconc Zcor)
297.4595
External Moments ∑Mxm 0 ∑Mzm 0
Moment due to Horizontal Forces ∑Mxh 167.7689 ∑Mzh 71.97
Moment due to Soil & Raft(Psoil+Fbase)*l/2 1190.89 (Psoil+Fbase)*b/2311.3445
0
Total Moment ∑Mx 3430.20 ∑Mz680.7772
Horizontal Forces ∑Hz -129.053 ∑Hx 55.364
Longitudinal direction ( Z - dir )
zcgcor SMx / Pv 5.634
Eccentricity along Z Dir from CG of Raft ex zcgcor-l/2 1.809
ez 1.809 > l / 6 1.275
36
Transverse direction ( X - dir )
CG from bottom edge xcgcor SMz / Pv 1.118
Eccentricity along X Dir from CG of Raft ex ycgcor-b/2 0.118
ex 0.118 < b / 6 0.333
ez / l 0.237 m
ex / b 0.059 m
Mx = Pv * ez
=608.8*1.81 = 1101.52 kNm
Mz =Pv * ex
=608.8*0.12 = 71.97 kNm
fmax Pv/A + 6*Mx/(b*l^2) + 6*Mz/(l*b^2)
= 608.8/15.3+6*1101.52/(2*7.65^2)+6*71.97/(7.65*2^2)
fmax 110.37 kN/m2 < Gross SBC 126 Safe
fmin 608.8/15.3-6*1101.52/(2*7.65^2)-6*71.97/(7.65*2^2)
fmin -30.79 kN/m2 LOC 21.811 %
Redistributed Pressure
ez / l = 0.237
ex / b = 0.059
From Tengs Chart Coeff (K) = 3.027
37
Max P= KQ/BL = 3.02694942934839 X 608.804 / 7.65 X 2
= 120.4456811 OK
Design Pressure
Along Z - Direction
fzmax =Pv/A*(1+6*ABS(ez/l)) =608.8/15.3x(1+6x0.237)
fzmax 100.678 kN/m2 220.7401143
fzmin =Pv/A*(1-6*ABS(ez/l)) = 608.8/15.3x(1-6x0.237) -61.57566987 fzmin 0.000 kN/m2
Along X - Direction
fxmax =Pv/A*(1+6*ABS(ex/b)) =608.8/15.3x(1+6x0.059)
fxmax 53.90 kN/m2
fxmin =Pv/A*(1-6*ABS(ex/b)) =608.8/15.3x(1-6x0.059)
fxmin 25.68 kN/m2
Pressure Along Z - Direction
LHS fzl 0.00 kN/m2
RHS fzr 100.68 kN/m2
Pressure Along X - Direction
38
Top fxt 53.90 kN/m2
Bottom fxb 25.68 kN/m2
Check For Overturning
R.M O.M
3262.43 Mx 167.7689 Mx
608.804 Mz 71.9732 Mz
Along X 19.45 Ok
Along Z 8.46 Ok
Check For Sliding
Restoring Force= 243.5216 KN
Sliding Force
55.364 Along X 4.398555018 Ok
129.053Along Z 1.886989067 Ok
39
Load calculations for combined Footing
Length of the footing = 7650 mm
Breadth of the footing b = 2000 mm
Depth of the footing D = 350 mm
Pressure from analysis
qmax = 110.37 kN/m²
qmin = -30.79 kN/m²
Uniformly distributed load
Self wt. of Fdn. 2.0 x 0.35 x 25 = 17.500 kN/m
Wt. of soil filling 23.20 kN/m
Total 40.699 kN/m
40
40.699 kN/m
Total downward force
40.699 x 7.7 + 0.00 + 0.00 311.345 kN
Max B.M= 160 kNm 152.817
Max S.F= 180 kN 174.061
SF
41
Design of Footing - X Direction ( Designed as cantilever)
Basic Data:
Concrete grade M30 fck = 30 N/mm²
Steel grade Fe415 fy = 415 N/mm²
Load factor ld= 1.5
Section Data:
Projection of footing from col. face l = 1000 mm
Breadth of the footing b = 1000 mm
Depth of the footing D = 350 mm
Clear cover to reinf. d' = 75 mm
Dia of bar used f = 12 mm
Load data:
Maximum pressure fmax= 53.90 kN/m2
Maximum Bending Moment M = 26.95 kN-m
Total moment M = 26.95 kN-m
Reinforcement:
Factored Bending Moment Mu = 40.43 kN-m
Eff. depth of footing d =350 - 75 - 12/2 = 269mm
Mu/bd²= 40.43x 10^6/(1000 x 269²) = 0.559
% of Reinforcement required ptr = 0.16
Minimum % of steel required pmin = 0.13
\ pt = 0.16
42
Area of steel required Ast = 425.6 mm²/m
Required spacing 12mm dia bars @ 266 mm c/c
Provide 12mm dia bars @ 200 mm c/c
Provided Area of steel Astp = 565.5 mm²/m
Design of Strap Beam
Dimensions
B= 600 mm
D= 750 mm
fck= 30 N/mm2
fy= 415 N/mm2
Maximum Bending moment KN-M = 160.00
Factored Bending Moment, Mu KN-M = 240.00
Effective depth of footing, d = 665.00
Shear Force V KN = 180.00
Factored Shear Force, Fu KN = 270.00
Mu/bd2, R = 0.90
% of reinforcement required (Refer BS8110-3 1985 Chart no 9 : pg 17) = 0.25
Min .% of reinforcement required = 0.20
Cover = 75.00
Dia of bar = 20.00
Area of cross section of bar = 314.29
Area of steel required ,As = 999.67
Provide number of bar dia required = 4.18
Hence, number of dia of bar provided = 6
43
Area of steel provided, As = 1885.71 0.47
CHECK FOR SHEAR
Factored Shear Force, Fu KN = 270.00
Nominal shear stress, tv N/mm2 = 0.68
B =7.370365484
Allowable Shear Stress =0.4852N/mm2
Provide shear reinforcement Vu - = 76.42
2 Legged Provide 10mm bar at = 200.00
Provide 10 mm @ 200.00 mm c/c
44
8 Design of Combined Foundation "F3"
Load Case LC 22
Net SBC SBCnet 106.25 kN/m2
Factor for inc in BC Fbc 1
Joint No 9 11
PEDESTAL MARK
Col Mark SUM 1 2
Z wrt 1 0 4.2
X wrt 1 0 0
P (kN) -30.26 295.35
Mx (kNm) 0 0.00 0.00
Hz (kN) -96.994 48.41 -48.59
Mz (kNm) 0 0.00 0.00
Hx (kN) -55.795 -27.55-28.25
Pedestal Size
lZ 0.6 0.6
lX 0.775 0.775
Pped 16.86 16.86
Depth of foundation from the level of point of application of forces
dforc 1.8 1.8
Depth of foundation below ground level (FGL)
Depth of foundation below Natural Ground Level (NGL)
Unit Weight of soil
45
Projections of Footing (from centreline of column)
LHS Cz1 0.9
RHS Cz2 0.9
Bottom Cx1 1.25
Top Cx2 1.25
Length of footing l 6.000 m
Width of footing b 2.500 m
Depth of footing d 0.350 m
Calculations :
Col Mark SUM 1 2
xcor 0.9 5.1
ycor 1.25 1.25
Axial Load including weight of Pedestal
Pconc 299 -13.41 312.21
Moment at base of foundation due to Horizontal Forces
Mxh -174.5892 -87.1344 -87.4548
Mzh -100.43 -49.581 -50.85
Moments due to Conc. Moments & Horizontal Forces(Myc = My + Myh ) (Mxc = Mx + Mxh )
Mxc -175 -87.1344 -87.4548
Mzc -100 -49.581 -50.85
Gross SBC SBCg=Fbc * SBCnet + gs * dfngl= 134.75 kN/m2 135 kN/m2
46
Total Axial Load incl wt of pedestal ( ∑Pconc ) ∑P 298.8005 kN
Area of foundation ( Provided ) A l * b 15 m2
Load due to soil Psoil gs*(df - d)*(A - ∑(lx*ly)) 307.43 kN
Weight of foundation Fbase A*d*25 131.25 kN
Total Vertical Load Pv ∑P + Psoil + Fbase 737.48 kN
CG of load system from bottom left corner of footing
Moments due to Pconc ∑ (Pconc Xcor) 1580.1909 ∑(Pconc Zcor) 373.500625
External Moments ∑Mxm ∑Mzm 0
Moment due to Horizontal Forces ∑Mxh 174.5892 ∑Mzh -100.43
Moment due to Soil & Raft ∑ (Psoil+Fbase)*l/2 1316.04(Psoil+Fbase)*b/2 548.349375
0
Total Moment ∑Mx 3070.82 ∑Mz 821.419
Horizontal Forces ∑Hz -96.994 ∑Hx -55.795
Horizontal Forces ∑Hz -96.994 ∑Hx -55.795
Horizontal Forces ∑Hz -96.994 ∑Hx -55.79
Horizontal Forces ∑Hz -96.994 ∑Hx -55.795
Longitudinal direction ( Z - dir )
zcgcor SMx / Pv 4.164
Eccentricity along Z Dir from CG of Raft ex zcgcor-l/2 ez 1.164 >l / 6 1.000
47
Transverse direction ( X - dir )
CG from bottom edge xcgcor ∑Mz / Pv 1.114
Eccentricity along X Dir from CG of Raft ex ycgcor-b/2 0.136
ex 0.136 < b / 6 0.417
ez / l 0.194 m
ex / b 0.054 m
Mx = Pv * ez
=737.48*1.16 = 858.38 kNm
Mz =Pv * ex
=737.48*0.14 = 100.43 kNm
fmax Pv/A + 6*Mx/(b*l^2) + 6*Mz/(l*b^2)
= 737.48/15+6*858.38/(2.5*6^2)+6*100.43/(6*2.5^2)
fmax 122.46 kN/m2 < Gross SBC 135 Safe
fmin 737.48/15-6*858.38/(2.5*6^2)-6*100.43/(6*2.5^2)
fmin -24.13 kN/m2 LOC 16.460 %
Redistributed Pressure
ez / l = 0.194
ex / b = 0.054
48
From Tengs Chart Coeff (K = 2.56794252 2.5767
Max P= KQ/BL = 2.56794251983484 X 737.48 / 6 X
= 126.25375 OK
Design Pressure
Along Z - Direction
fzmax =Pv/A*(1+6*ABS(ez/l)) =737.5/15x(1+6x0.194)
fzmax 107.110 kN/m2 244.9190667
fzmin =Pv/A*(1-6*ABS(ez/l)) =737.5/15x(1-6x0.194)-48.25773333
fzmin 0.000 kN/m2
Along X - Direction
fxmax =Pv/A*(1+6*ABS(ex/b)) =737.5/15x(1+6x0.054)
fxmax 65.23 kN/m2
fxmin =Pv/A*(1-6*ABS(ex/b)) =737.5/15x(1-6x0.054)
fxmin 33.10 kN/m2
Pressure Along Z - Direction
LHS fzl 0.00 kN/m2
RHS fzr 107.11 kN/m2
Pressure Along X - Direction
Top fxt 33.10 kN/m2
49
Bottom fxb 65.23 kN/m2
Check For Overturning
R.M O.M
2896.23 Mx 174.5892 Mx
921.85 Mz 100.431 Mz
Along X 16.59 Ok
Along Z 9.18 Ok
Check For Sliding
Restoring Force= 294.992 KN
Sliding Force
55.795 Along X 5.287068734 Ok
96.994 Along Z 3.041342763 Ok
Load calculations for combined Footing
Length of the footing l = 6000 mm
Breadth of the footing b = 2500 mm
Depth of the footing D = 350 mm
Pressure from analysis
qmax = 122.46 kN/m²
qmin = -24.13 kN/m²
50
LOADING
Uniformly distributed load
Self wt. of Fdn. 2.5 x 0.35 x 25 = 21.875 kN/m
Wt. of soil filling 51.24 kN/m
Total 73.113 kN/m
73.113 kN/m
Total downward force
73.113 x 6.0 + 0.00 + 0.00 438.680 kN
51
BM
Max B.M= 130 kNm 126.595
Max S.F= 150 kN 149.884
SF
Design of Footing - Z Direction ( Designed as cantilever)
Basic Data:
Concrete grade M30 fck = 30 N/mm²
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Steel grade Fe415 fy = 415 N/mm²
Load factor ld= 1.5
Section Data:
Projection of footing from col. face l= 1250 mm
Breadth of the footing b= 1000 mm
Depth of the footing D= 350 mm
Clear cover to reinf. d'= 75 mm
Dia of bar used f = 12 mm
Load data:
Maximum pressure fmax= 65.23 kN/m2
Maximum Bending Moment M = 50.96 kN-m
Total moment M = 50.96 kN-m
Reinforcement:
Factored Bending Moment Mu = 76.45 kN-m
Eff. depth of footing d =350 - 75 - 12/2 =269mm Mu/bd² = 76.45x 10^6/(1000 x 269²) =1.056
% of Reinforcement required ptr =0.31
Minimum % of steel required pmin = 0.13
\ pt = 0.31
Area of steel required Ast =821.8 mm²/m
Required spacing 12mm dia bars @ 138 mm c/c
Provide 12mm dia bars @125mm c/c
Provided Area of steel Astp = 904.8 mm²/m
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0 126.25375
2.5 8.01
85.45932963
98.18245899
Moment =41.90260613-11.38176563 =30.52084051
M/bd2 =0.632678663
Pt= 0.18 0.31
Ast= 821.8482124
Spacing= 137.5436465
Shear Soil
Vu= 66.60144501 18.1611 48.44034501
Tv= 0.270113448
B= 11.40125568
Tc= 0.40274325 OK
Design of Strap Beam
Dimensions
B = 600 mm
D = 750 mm
Fck = 30 N/mm2
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fy = 415 N/mm2
Maximum Bending moment KN-M = 130.00
Factored Bending Moment, Mu KN-M = 195.00
Effective depth of footing, d = 665.00
Shear Force V KN = 150.00
Factored Shear Force, Fu KN = 225.00
Mu/bd2, R = 0.73
% of reinforcement required = 0.20
Min .% of reinforcement required = 0.20
Cover = 75.00
Dia of bar = 20.00
Area of cross section of bar = 314.29
Area of steel required ,As = 812.22
Provide number of bar dia required = 3.58
Hence, number of dia of bar provided = 6
Area of steel provided, As = 1885.71 0.47
CHECK FOR SHEAR
Factored Shear Force, Fu KN = 225.00
Nominal shear stress, tv N/mm2 = 0.56
B = 7.370365484
Allowable Shear Stress = 0.4852 N/mm2
Provide shear reinforcement Vu - = 31.42
2 Legged Provide 10mm bar at = 200.00
Provide 10 mm @ 200.00 mm c/c
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