Design of Thrust Block
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Transcript of Design of Thrust Block
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)