design of thrust block
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DESIGN OF THRUST BLOCKS at RISING NEAR DELIVERY CISTERN
DATA ASSUMED
Density of concrete Yc 2500 cover of earth on top Tcov 1Ht of ThrustBlock=h= h 2Width of ThrustBlock= b 4.5LTB= length of ThrustBlock= L 6GL. Above base of block ht 1Fw=ressist forc due to soil frictionFb=lateral soil resist.gainst blockFp=lateral soil resist.gainst pipe
Soil parametersInternal angle of friction in degrees fy 30Soil cohesion =C= co 4880Soil density =ds ys 1800Internal angle of friction around the block in degrees 26Fric.ressit. Of soil(0.25 to 0.4) 0.3SBC BC 25Density of water= 1000
Pipeline parametersAngle of deviation 15 alpa mDia of pipe 0.8 d mArea of pipe 0.50272 A sqmWater hammer pressure 98.14 Ph t/sqmInternal pressu. At bend=P 86.32 Pi t/sqmThi. Of pipe 0.007 t m
alpa=15alpa/2=15
FOR 15 degree bend
Horizontal thrustF=2PA sin alpa/22x86.32x0.50272x0.3827 11.326
i Lateral resistance tocounteract the horizontal thrust
wt . TB 3x3-0.50272)x3x2500 127464.00
wt. of pipe 3.142x0.8x0.007x6x7.85 828.73
wt . Of water in pipe 0.50272x6x1000 3016.32
wt of earth 15x0.8x1x1800 0Total WT.(vertical load) Fv 131309.05Total force available considering fri. resistance of soil
92731.7312
Fw=f* totalwt 0.3x131309.054 39392.716ii Lateral resist. Of soil against the block
Ht of ThrustBlock=h= 3Width of ThrustBlock= 2.6LTB= length of ThrustBlock= 3sin0 =sin30=.5 0.5
(1-sin26) (1+sin0)/(1-sin0) 3 1.4384
(1+sin26) (1-sin0)/(1+sin0) 0.333 0.5616
Ppass= .5*ds*h^2*LTB*((1+sin0)/(1-sin0))
Ppass= 0.5x1x1x1.4384/0.5616
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipeFp= ds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.5
Fp= 1800x3x(15-3)x0.333-2x4880x(15-3)x0.333^0.5
Factor safety=(Fw+Fb+Fp)/hor,thrust(39392.716+2305.128+-46007.045)/11.326
Angle of deviation P=Internal pressure
AT +363.00 Elevation 15 13 11.326
Provide 10mm tor steel bars at 250mm c/c on all faces both directions
Po=YS*HT*(1-SIN0)Po=0 where ht=0 0Po(1)= where ht=1 900Fo=(Po+Po(1)*ht/2 450To=radialthrust /unit length(Fv*(b'-b/3)+Fo*h2)/h1/L 16438.6318Fv inkg/m 131309.05b'=b/2 2.25
0.333h1=h/2 1
CHECK THE LENGTHlength= (Fp(bend)/ToFp(bend)=T=thrust due to deflectionin pipe L 5.6410857
Hor. Force due to inter.Pressure
h2=point@whichFo acts=ht/3 since triangular distribution
DESIGN OF THRUST BLOCKS at RISING NEAR DELIVERY CISTERN
t/sqm angle 15m
87870
t/sqmt/cum
t/sqmt/cum
Sin45 0.7071Sin30 0.5Sin22.5 0.3827Sin15 0.2588Sin11.25 0.1951Sin7.5 0.1305tonnes
kg
kg
kg
kgkg
kg
.5*ds*h^2*LTB*((1+sin0)/(1-sin0))
0.5x1x1x1.4384/0.56162305.128
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipeds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.5
1800x3x(15-3)x0.333-2x4880x(15-3)x0.333^0.5-46007 tonnes
-380.470 >1.5 Hence SAFE
Fp in tonnes Size of thrust blockL B D
### 2305.128 -46007.045 -380.470 3 2.6 3 234
Fw in tonnes
Fb in tonnes
Factor of safety
Surface steel at 5 kg/sqm (kgs)
DESIGN OF THRUST BLOCKS
DATA ASSUMED
Density of concrete 2.4 t/sqmmin. cover of earth on T.B in M 1 mFw=ressist forc due to soil frictionFb=lateral soil resist.gainst blockFp=lateral soil resist.gainst pipe
Soil parametersInternal angle of friction in degrees 30Soil cohesion =C= 4.9 t/sqmSoil density =ds 1.6 t/cumFric.ressit. Of soil(0.25 to 0.4) 0.3
Sin45 0.7071Sin30 0.5
FOR 45 degree bend alpa=45 Sin22.5 0.3827Sin15 0.2588
Horizontal thrust Sin11.25 0.1951F=2PA sin alpa/2 Sin7.5 0.1305
Sin 3.75 0.0654110.149827657 tonnes
i Lateal resistance to counteract the horizontal thrust
wt . TB 41.79 tonnes
wt. of pipe 1.97 tonnes
wt . Of water in pipe 7.855 tonnes
wt of earth 16 tonnes67.61
Total force available considering fri. resistance of soil
Fw=f* totalwt 20.284ii Lateral resist. Of soil against the block
Ht of TB=h=2.4 2.4LTB length of TB= 3.5 .5*ds*h^2*LTB*((1+sin0)/(1-sin0))+2*C*h*LTB*((1+sin0)/(1-sn0))^.5sin0 =sin30=.5 0.5
0.51.5 Fb= 190.9664
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipe
Fp= ds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.5
-28.45721 tonnes
Factor safety=Fw+Fb+Fp/hor,thrust1.659 >1.5
Density of concrete 2.4 t/sqmmin. cover of earth on T.B in M 1 mFw=ressist forc due to soil frictionFb=lateral soil resist.gainst blockFp=lateral soil resist.gainst pipe
Soil parametersInternal angle of friction in degrees 30Soil cohesion =C= 4.9 t/sqmSoil density =ds 1.8 t/cumFric.ressit. Of soil(0.25 to 0.4) 0.3
Sin45 0.7071Sin30 0.5
FOR 45 degree bend alpa=45 Sin22.5 0.3827alpa/2=22.5 Sin15 0.2588
Horizontal thrust Sin11.25 0.1951F=2PA sin alpa/2 Sin7.5 0.1305
10.661 tonnes
i Lateal resistance tocounteract the horizontal thrust
wt . TB 26.05 tonnes
wt. of pipe 5.92 tonnes
wt . Of water in pipe 31.42 tonnes
wt of earth 36 tonnesTotal WT. 99.39Total force available considering fri. resistance of soil
Fw=f* totalwt 29.817ii Lateral resist. Of soil against the block
Ht of TB=h=2.6 2.6LTB length of TB= 3 .5*ds*h^2*LTB*((1+sin0)/(1-sin0))+2*C*h*LTB*((1+sin0)/(1-sn0))^.5sin0 =sin30=.5 0.5
0.51.5 Fb= 187.154
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipe
Fp= ds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.5
-28.68623 tonnes
Factor safety=(Fw+Fb+Fp)/hor,thrust17.661 >1.5
Angle of deviation
AT +300.00 Elevation 45 105 252.513 41.539 467.885AT +360.00 Elevation 45 18 43.288 35.027 311.923AT +361.00 Elevation 22.5 16 19.616 29.817 187.154AT +363.00 Elevation 15 13 10.661 29.817 187.154
Provide 10mm tor steel bars at 250mm c/c on all faces both directions
P=Internal pressure
Hor. Force due to inter.Pressure
Fw in tonnes
Fb in tonnes
DESIGN OF THRUST BLOCKS
Pipeline parametersLength. Of pipe 10 mDia of pipe 1 mInternal pressu. At bend 183.21 t/sqmThi. Of pipe 0.008 m
.5*ds*h^2*LTB*((1+sin0)/(1-sin0))+2*C*h*LTB*((1+sin0)/(1-sn0))^.5
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipe
ds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.5
Hence SAFE
Pipeline parametersLength. Of pipe 10 mDia of pipe 2 mInternal pressu. At bend 13 t/sqmThi. Of pipe 0.012 m
.5*ds*h^2*LTB*((1+sin0)/(1-sin0))+2*C*h*LTB*((1+sin0)/(1-sn0))^.5
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipe
ds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.5
Hence SAFE
Factor of safety Size of thrust blockL B D
-10.245 1.977 7.5 2.6 2.6 457.6-20.49 7.542 5 2.6 2.6 327.6
-28.686 9.598 3 2.6 2.6 223.6-28.686 17.661 3 2.6 2.6 223.6
Fp in tonnes
Surface steel at 5 kg/sqm (kgs)
DESIGN OF THRUST BLOCKS
DATA ASSUMED
Density of concrete 2.4min. cover of earth on T.B in M 1Fw=ressist forc due to soil frictionFb=lateral soil resist.gainst blockFp=lateral soil resist.gainst pipe
Soil parametersInternal angle of friction in degrees 30Soil cohesion =C= 4.9Soil density =ds 1.6Fric.ressit. Of soil(0.25 to 0.4) 0.3Density of water= 1
Pipeline parametersLength. Of pipe 10 mDia of pipe 2 mArea of pipe 3.142 sqmInternal pressu. At bend=P 13 t/sqmThi. Of pipe 0.012 m
alpa=15alpa/2=7.5
FOR 15 degree bend
Horizontal thrustF=2PA sin alpa/22x13x3.142x0.1305 10.661
i Lateral resistance tocounteract the horizontal thrust
wt . TB 2.6x2.6-3.142)x3x2.4 26.05
wt. of pipe 3.142x2x0.012x10x7.85 5.92
wt . Of water in pipe 3.142x10x1 31.42
wt of earth 10x2x1x1.6 32Total WT. 95.39Total force available considering fri. resistance of soil
Fw=f* totalwt 0.3x95.389 28.617ii Lateral resist. Of soil against the block
Ht of ThrustBlock=h= 2.6Width of ThrustBlock=h= 2.6
LTB= length of ThrustBlock= 3sin0 =sin30=.5 0.5
(1-sin30) .5 (1+sin0)/(1-sin0) 3 Fb=
(1+sin30) 1.5 (1-sin0)/(1+sin0) 0.3330.5x1.6x2.6x2.6x3x3+2x4.9x2.6x3x3^.5
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipe
Fp=1.6x2.6x(10-3)x0.333-2x4.9x(10-3)x0.333^0.5
Factor safety=(Fw+Fb+Fp)/hor,thrust(28.617+181.07+-29.889)/10.661
Angle of deviation P=Internal pressure
AT +300.00 Elevation 45 105 252.513AT +360.00 Elevation 45 18 43.288AT +361.00 Elevation 22.5 16 19.616AT +363.00 Elevation 15 13 10.661
Provide 10mm tor steel bars at 250mm c/c on all faces both directions
Hor. Force due to inter.Pressure
DESIGN OF THRUST BLOCKS
t/sqmm
t/sqmt/cum
t/cum
Sin45 0.7071Sin30 0.5Sin22.5 0.3827Sin15 0.2588Sin11.25 0.1951Sin7.5 0.1305tonnes
tonnes
tonnes
tonnes
tonnestonnes
.5*ds*h^2*LTB*((1+sin0)/(1-sin0))+2*C*h*LTB*((1+sin0)/(1-sn0))^.5
0.5x1.6x2.6x2.6x3x3+2x4.9x2.6x3x3^.5181.07
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipe
ds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.51.6x2.6x(10-3)x0.333-2x4.9x(10-3)x0.333^0.5
-29.889 tonnes
16.865 >1.5 Hence SAFE
Factor of safety Size of thrust blockL B D
41.539 467.885 -10.245 1.977 7.5 2.6 2.6 457.635.027 311.923 -20.49 7.542 5 2.6 2.6 327.629.817 187.154 -28.686 9.598 3 2.6 2.6 223.628.617 181.07 -29.889 16.865 3 2.6 2.6 223.6
Fw in tonnes
Fb in tonnes
Fp in tonnes
Surface steel at 5 kg/sqm (kgs)
DESIGN OF THRUST BLOCKS at RISING NEAR DELIVERY CISTERN
DATA ASSUMED
Density of concrete 2.4 t/sqmmin. cover of earth on T.B in M 1 mFw=ressist forc due to soil frictionFb=lateral soil resist.gainst blockFp=lateral soil resist.gainst pipe
Soil parametersInternal angle of friction in degrees 30Soil cohesion =C= 4.9 t/sqmSoil density =ds 1.6 t/cumFric.ressit. Of soil(0.25 to 0.4) 0.3Density of water= 1 t/cum
Pipeline parametersLength. Of pipe 10 mDia of pipe 2 mArea of pipe 3.142 sqmInternal pressu. At bend=P 13 t/sqmThi. Of pipe 0.012 m
alpa=15 Sin45alpa/2=15 Sin30
FOR 15 degree bend Sin22.5Sin15
Horizontal thrust Sin11.25F=2PA sin alpa/2 Sin7.52x13x3.142x0.3827 10.661 tonnes
i Lateral resistance tocounteract the horizontal thrust
wt . TB 3x3-3.142)x3x2.4 42.18 tonnes
wt. of pipe 3.142x2x0.012x10x7.85 5.92 tonnes
wt . Of water in pipe 3.142x10x1 31.42 tonnes
wt of earth 10x2x1x1.6 32 tonnesTotal WT. 111.52 tonnesTotal force available considering fri. resistance of soil
Fw=f* totalwt 0.3x111.517 33.455ii Lateral resist. Of soil against the block
Ht of ThrustBlock=h= 3Width of ThrustBlock= 2.6LTB= length of ThrustBlock= 3sin0 =sin30=.5 0.5
(1-sin30) (1+sin0)/(1-sin0) 3
(1+sin30) (1-sin0)/(1+sin0) 0.333
Fb= .5*ds*h^2*LTB*((1+sin0)/(1-sin0))+2*C*h*LTB*((1+sin0)/(1-sn0))^.5
Fb 0.5x1.6x3x2.6x3x3+2x4.9x3x3x3^.5208.927
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipeFp= ds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.5
Fp= 1.6x3x(10-3)x0.333-2x4.9x(10-3)x0.333^0.5-28.398
Factor safety=(Fw+Fb+Fp)/hor,thrust(33.455+208.927+-28.398)/10.661 20.072
Angle of deviation P=Internal pressure
AT +363.00 Elevation 15 13 10.661 33.455
Provide 10mm tor steel bars at 250mm c/c on all faces both directions
Hor. Force due to inter.Pressure
Fw in tonnes
DESIGN OF THRUST BLOCKS at RISING NEAR DELIVERY CISTERN
0.70710.5
0.38270.25880.19510.1305
.5*ds*h^2*LTB*((1+sin0)/(1-sin0))+2*C*h*LTB*((1+sin0)/(1-sn0))^.5
0.5x1.6x3x2.6x3x3+2x4.9x3x3x3^.5
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipeds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.5
1.6x3x(10-3)x0.333-2x4.9x(10-3)x0.333^0.5tonnes
>1.5 Hence SAFE
Fp in tonnes Size of thrust blockL B D
208.927 -28.398 20.072 3 2.6 3 234
Fb in tonnes
Factor of safety
Surface steel at 5 kg/sqm (kgs)
DESIGN OF THRUST BLOCKS at CONVERING LOCATION
DATA ASSUMED
Density of concrete 2.4 t/sqmmin. cover of earth on T.B in M 1 mFw=ressist forc due to soil frictionFb=lateral soil resist.gainst blockFp=lateral soil resist.gainst pipe
Soil parametersInternal angle of friction in degrees 30Soil cohesion =C= 4.9 t/sqmSoil density =ds 1.6 t/cumFric.ressit. Of soil(0.25 to 0.4) 0.3Density of water= 1 t/cum
Pipeline parametersLength. Of pipe 5 mDia of pipe 2 mArea of pipe 3.142 sqmInternal pressu. At bend=P 16 t/sqmThi. Of pipe 0.012 m
alpa=22.5 Sin45alpa/2=22.5 Sin30
FOR 22.5 degree bend Sin22.5Sin15
Horizontal thrust Sin11.25F=2PA sin alpa/2 Sin7.52x16x3.142x0.3827 19.616 tonnes
i Lateral resistance tocounteract the horizontal thrust
wt . TB 2.6x2.6-3.142)x3x2.4 26.05 tonnes
wt. of pipe 3.142x2x0.012x5x7.85 2.96 tonnes
wt . Of water in pipe 3.142x5x1 15.71 tonnes
wt of earth 5x2x1x1.6 16 tonnesTotal WT. 60.72 tonnesTotal force available considering fri. resistance of soil
Fw=f* totalwt 0.3x60.719 18.216ii Lateral resist. Of soil against the block
Ht of ThrustBlock=h= 2.6Width of ThrustBlock= 3LTB= length of ThrustBlock= 3sin0 =sin30=.5 0.5
(1-sin30) (1+sin0)/(1-sin0) 3
(1+sin30) (1-sin0)/(1+sin0) 0.333
Fb= .5*ds*h^2*LTB*((1+sin0)/(1-sin0))+2*C*h*LTB*((1+sin0)/(1-sn0))^.5
Fb 0.5x1.6x2.6x3x3x3+2x4.9x2.6x3x3^.5188.558
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipeFp= ds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.5
Fp= 1.6x2.6x(5-3)x0.333-2x4.9x(5-3)x0.333^0.5-8.54
Factor safety=(Fw+Fb+Fp)/hor,thrust(18.216+188.558+-8.54)/19.616 10.106
Angle of deviation P=Internal pressure
AT +361.00 Elevation 22.5 16 19.616 18.216
Provide 10mm tor steel bars at 250mm c/c on all faces both directions
Hor. Force due to inter.Pressure
Fw in tonnes
DESIGN OF THRUST BLOCKS at CONVERING LOCATION
0.70710.5
0.38270.25880.19510.1305
.5*ds*h^2*LTB*((1+sin0)/(1-sin0))+2*C*h*LTB*((1+sin0)/(1-sn0))^.5
0.5x1.6x2.6x3x3x3+2x4.9x2.6x3x3^.5
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipeds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.5
1.6x2.6x(5-3)x0.333-2x4.9x(5-3)x0.333^0.5tonnes
>1.5 Hence SAFE
Fp in tonnes Size of thrust blockL B D
188.558 -8.54 10.106 3 3 2.6 258
Fb in tonnes
Factor of safety
Surface steel at 5 kg/sqm (kgs)
DESIGN OF THRUST BLOCKS 2nd BEND at TOP OF INCLINED SHAFT
DATA ASSUMED
Density of concrete 2.4 t/sqmmin. cover of earth on T.B in M 1 mFw=ressist forc due to soil frictionFb=lateral soil resist.gainst blockFp=lateral soil resist.gainst pipe
Soil parametersInternal angle of friction in degrees 30Soil cohesion =C= 4.9 t/sqmSoil density =ds 1.6 t/cumFric.ressit. Of soil(0.25 to 0.4) 0.3Density of water= 1 t/cum
Pipeline parametersLength. Of pipe 10 mDia of pipe 2 mArea of pipe 3.142 sqmInternal pressu. At bend=P 18 t/sqmThi. Of pipe 0.012 m
alpa=45 Sin45alpa/2=22.5 Sin30
FOR 45 degree bend Sin22.5Sin15
Horizontal thrust Sin11.25F=2PA sin alpa/2 Sin7.52x18x3.142x0.3827 43.288 tonnes
i Lateral resistance tocounteract the horizontal thrust
wt . TB 4x4-3.142)x4x2.4 123.44 tonnes
wt. of pipe 3.142x2x0.012x10x7.85 5.92 tonnes
wt . Of water in pipe 3.142x10x1 31.42 tonnes
wt of earth 10x2x1x1.6 32 tonnesTotal WT. 192.78 tonnesTotal force available considering fri. resistance of soil
Fw=f* totalwt 0.3x192.776 57.833ii Lateral resist. Of soil against the block
Ht of ThrustBlock=h= 4Width of ThrustBlock= 4LTB= length of ThrustBlock= 4sin0 =sin30=.5 0.5
(1-sin30) (1+sin0)/(1-sin0) 3
(1+sin30) (1-sin0)/(1+sin0) 0.333
Fb= .5*ds*h^2*LTB*((1+sin0)/(1-sin0))+2*C*h*LTB*((1+sin0)/(1-sn0))^.5
Fb 0.5x1.6x4x4x4x3+2x4.9x4x4x3^.5425.186
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipeFp= ds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.5
Fp= 1.6x4x(10-4)x0.333-2x4.9x(10-4)x0.333^0.5-21.144
Factor safety=(Fw+Fb+Fp)/hor,thrust(57.833+425.186+-21.144)/43.288 10.670
Angle of deviation P=Internal pressure
AT +360.00 Elevation 45 18 43.288 57.833
Provide 10mm tor steel bars at 250mm c/c on all faces both directions
Hor. Force due to inter.Pressure
Fw in tonnes
DESIGN OF THRUST BLOCKS 2nd BEND at TOP OF INCLINED SHAFT
0.70710.5
0.38270.25880.19510.1305
78193492.37760023838811.76641281
37932.9225930122.4047184810591
.5*ds*h^2*LTB*((1+sin0)/(1-sin0))+2*C*h*LTB*((1+sin0)/(1-sn0))^.5
0.5x1.6x4x4x4x3+2x4.9x4x4x3^.5
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipeds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.5
1.6x4x(10-4)x0.333-2x4.9x(10-4)x0.333^0.5tonnes
>1.5 Hence SAFE
Fp in tonnes Factor of safety Size of thrust blockL B D
425.186 -21.144 10.670 4 4 4 480
Fb in tonnes
Surface steel at 5 kg/sqm (kgs)
DESIGN OF THRUST BLOCKS 1st BEND IN INCLINED SHAFT
DATA ASSUMED
Density of concrete 2.4 t/sqmmin. cover of earth on T.B in M 1 mFw=resisting forc due to soil frictionFb=lateral soil resistance.gainst blockFp=lateral soil resistance.gainst pipe
Soil parametersInternal angle of friction in degrees 30Soil cohesion =C= 4.9 t/sqmSoil density =ds 2.6 t/cumFric.ressit. Of soil(0.25 to 0.4) 0.3Density of water= 1 t/cum
Pipeline parametersLength. Of pipe 7.5 mDia of pipe 2 mArea of pipe 3.142 sqmInternal pressu. At bend=P 105 t/sqmThi. Of pipe 0.012 m
alpa=45 Sin45alpa/2=22.5 Sin30
FOR 45 degree bend Sin22.5Sin15
Horizontal thrust Sin11.25F=2PA sin alpa/2 Sin7.52x105x3.142x0.3827 252.513 tonnes
i Lateral resistance tocounteract the horizontal thrust
wt . TB 3x3x0.7855-3.142)x7.5x2 70.70 tonnes
wt. of pipe 3.142x2x0.012x7.5x7.85 4.44 tonnes
wt . Of water in pipe 3.142x7.5x1 23.565 tonnes
wt of earth 7.5x2x1x2.6 39 tonnesTotal WT. 137.70 tonnesTotal force available considering fri. resistance of soil
Fw=f* totalwt 0.3x137.7 41.310ii Lateral resist. Of soil against the block
Ht of ThrustBlock=h= 3Width of ThrustBlock=b 3LTB= length of ThrustBlock= 7.5sin0 =sin30=.5 0.5
(1-sin30) (1+sin0)/(1-sin0) 3
(1+sin30) (1-sin0)/(1+sin0) 0.333
Fb= .5*ds*h*b*.7855*LTB*((1+sin0)/(1-sin0))+2*C*h*LTB*((1+sin0)/(1-sn0))^.5
Fb 0.5x2.6x3x3x0.7855x7.5x3+2x4.9x3x7.5x3^.5588.7
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipeFp= ds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.5
Fp= 2.6x3x(7.5-7.5)x0.333-2x4.9x(7.5-7.5)x0.333^0.50
Factor safety=(Fw+Fb+Fp)/hor,thrust(41.31+588.7+0)/252.513 2.495
Angle of deviation P=Internal pressure
AT +300.00 Elevation 45 105 252.513 41.310
Provide 10mm tor steel bars at 250mm c/c on all faces both directions
Hor. Force due to inter.Pressure
Fw in tonnes
DESIGN OF THRUST BLOCKS 1st BEND IN INCLINED SHAFT
0.70710.5
0.38270.25880.19510.1305
.5*ds*h*b*.7855*LTB*((1+sin0)/(1-sin0))+2*C*h*LTB*((1+sin0)/(1-sn0))^.5
0.5x2.6x3x3x0.7855x7.5x3+2x4.9x3x7.5x3^.5
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipeds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.5
2.6x3x(7.5-7.5)x0.333-2x4.9x(7.5-7.5)x0.333^0.5tonnes
>1.5 Hence SAFE
Fp in tonnes Size of thrust blockL B D
588.7 0 2.495 7.5 3 3 540
Fb in tonnes
Factor of safety
Surface steel at 5 kg/sqm (kgs)
DESIGN OF THRUST BLOCKS 1st BEND IN INCLINED SHAFT
DATA ASSUMED
Density of concrete 2.4 t/sqmmin. cover of earth on T.B in M 1 mFw=ressist forc due to soil frictionFb=lateral soil resist.gainst blockFp=lateral soil resist.gainst pipe
Soil parametersInternal angle of friction in degrees 30Soil cohesion =C= 4.9 t/sqmSoil density =ds 1.6 t/cumFric.ressit. Of soil(0.25 to 0.4) 0.3Density of water= 1 t/cum
Pipeline parametersLength. Of pipe 10 mDia of pipe 2 mArea of pipe 3.142 sqmInternal pressu. At bend=P 105 t/sqmThi. Of pipe 0.012 m
alpa=45 Sin45alpa/2=22.5 Sin30
FOR 45 degree bend Sin22.5Sin15
Horizontal thrust Sin11.25F=2PA sin alpa/2 Sin7.52x105x3.142x0.3827 252.513 tonnes
i Lateral resistance tocounteract the horizontal thrust
wt . TB 2.6x2.6-3.142)x7.5x2.4 65.12 tonnes
wt. of pipe 3.142x2x0.012x10x7.85 5.92 tonnes
wt . Of water in pipe 3.142x10x1 31.42 tonnes
wt of earth 10x2x1x1.6 32 tonnesTotal WT. 134.46 tonnesTotal force available considering fri. resistance of soil
Fw=f* totalwt 0.3x134.464 40.339ii Lateral resist. Of soil against the block
Ht of ThrustBlock=h= 2.6Width of ThrustBlock= 2.6LTB= length of ThrustBlock= 7.5sin0 =sin30=.5 0.5
(1-sin30) (1+sin0)/(1-sin0) 3
(1+sin30) (1-sin0)/(1+sin0) 0.333
Fb= .5*ds*h^2*LTB*((1+sin0)/(1-sin0))+2*C*h*LTB*((1+sin0)/(1-sn0))^.5
Fb 0.5x1.6x2.6x2.6x7.5x3+2x4.9x2.6x7.5x3^.5452.675
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipeFp= ds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.5
Fp= 1.6x2.6x(10-7.5)x0.333-2x4.9x(10-7.5)x0.333^0.5-10.675
Factor safety=(Fw+Fb+Fp)/hor,thrust(40.339+452.675+-10.675)/252.513 1.910
Angle of deviation P=Internal pressure
AT +300.00 Elevation 45 105 252.513 40.339
Provide 10mm tor steel bars at 250mm c/c on all faces both directions
Hor. Force due to inter.Pressure
Fw in tonnes
DESIGN OF THRUST BLOCKS 1st BEND IN INCLINED SHAFT
0.70710.5
0.38270.25880.19510.1305
.5*ds*h^2*LTB*((1+sin0)/(1-sin0))+2*C*h*LTB*((1+sin0)/(1-sn0))^.5
0.5x1.6x2.6x2.6x7.5x3+2x4.9x2.6x7.5x3^.5
Lateral resistance of soil when the thrust lock isfree to yield away from the sol mass i.e,the portion of projected pipeds*h*(L.P-LTB)*((1-sin0)/(1+sin0))-2*C*(L.P-LTB)*((1-sin0)/(1+sn0))^.5
1.6x2.6x(10-7.5)x0.333-2x4.9x(10-7.5)x0.333^0.5tonnes
>1.5 Hence SAFE
Fp in tonnes Size of thrust blockL B D
452.675 -10.675 1.910 7.5 2.6 2.6 457.6
Fb in tonnes
Factor of safety
Surface steel at 5 kg/sqm (kgs)
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