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DESIGN OF PCC ABUTMENT - OPEN FOUNDATION For "T beam cum slab " super structure with four beams& with footpath on both Name of Work: Reconstruction of Bridge ALL CELLS IN RED COLOUR ARE MEANT FOR DATA INPUT Expansion 40 mm Thickness of Wearing Coat 75 mm Approach slab Road leve RL 102.450 395 mm Depth of Super Structure @ Centre = 22.5 0 2166 mm 21 90 0 Depth of Super Structure @ Edges = 2030 mm 96 mm 200 mm 300 mm BOB RL 99.61 300 320 380 50 Start of Batter RL 99.61 1000 3519 22.5 0 105.5 1211 MFL RL 99.00 99.68 0 0.320 1000 276 1552 Ground level RL 98.00 1900 Heel side Toe side 500 600 1000 1200 500 top of fdn RL 96.10 2800 500 2100 1400 500 600 700 RL 94.000 1000 600 2200 1600 5400 Pressure Developed in kN/m2 Minimum Maxim no tension 58.29 Normal Case 184 < for soil, tension is not permitted,cl.706.3.3.1 In case of rock, refer cl 706.3.3.2 no tension 21.85 Seismic Case 231 < d = q = d = q = ka2 = a b

Design of Pcc Abutment - Open Foundation

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Design of Pcc Abutment - Open Foundation

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inputDESIGN OF PCC ABUTMENT - OPEN FOUNDATIONFor "T beam cum slab " super structure with four beams& with footpath on both sidesName of Work: Reconstruction of BridgeALL CELLS IN RED COLOUR ARE MEANT FOR DATA INPUTExpansion gap40mmThickness of Wearing Coat75mmApproach slabRoad levelRL102.450395mmDepth of Super Structure @ Centre =Thumb ruled =22.502166mm2166mmBase width = 0.5H to 0.7H (H= road level to fdn level)q =900Depth of Super Structure @ Edges =Toe length = 0.3 x base width2030mmIn this case,96mmBase width =4225to5915mm200mmToe length =1620mm300mmBOBRL99.619Front batter may be provided If necessary30032038050Start of BatterRL99.61910003519d =22.50105.54134697361211MFLRL99.000q =99.680ka2 =0.3201000276.04433077581552Ground levelRL98.0001900Heel sideToe side50060010001200500top of fdnRL96.100280050070021001400500600700700700RL94.0001000600220016005400Pressure Developed in kN/m2MinimumMaximumno tension58.29Normal Case184.012Hence safe.Factor of safety against overturning with seismic(I) With seismic (with live load)=447.2+75.637+2.9769480519+1969.4844994+0618.1+0.000+78.94+301.3831653981=2.4993281148>1.5Hence safe.(II) With seismic (without live load)=447.2+0.000+0+1969.4844994+0618.1+104.498+0.00+281.61978125=2.4066139415>1.5Hence safe.Check for Sliding without seismic(without liveload)Total horizontal force=Act.ear.pressure+Llsurcharge+Long.force=174.15+49.47+4.380=228.0kNTotal resisting force=0.5x (DL + Self weight )=0.5x(140.625+561)=350.946kNFactor of safety against sliding=350.946227.997=1.54>1.5Hence safe.Check for Sliding with seismic(without liveload)Total horizontal force=Act.ear.pressure+Llsurcharge+Long.force+Seismic force=174.15+24.73315+4.380+50.0=253.2kNTotal resisting force=0.5x (DL + LL + Self weight )=0.5x(140.625+0+561=350.946kNFactor of safety against sliding=350.946253.221Hence safe.The section is safe against sliding=1.39>1.250Check for Stability in Span Dislodged ConditionCheck for OverturningResisting MomentDead load moment=0.00kNmLive load moment=0.00kNmVertical moment=0.00kNmSelfweight moment=1969.484kNmPassive earth pressure moment=0.00kNmTotal restraining moment=1969.484kNmOverturning momentActive earth pressure=618.062kNmLive load surcharge=0.000kNmLongitudinal moment=0.00kNmSeismic moment=0.00kNmTotal overturning moment=618.062kNmFactor of safety against overturning=1969.484kNm618.062The section is safe against overturning=3.19>1.5Check for SlidingTotal horizontal force=Act.ear.pressure+Llsurcharge+Long.forceSeismic force=174.15+0+0.00+0.00=174.2kNTotal horizontal resisting force=0.50x (DL + LL + Self weight )=0.5x(0.00+0.00+561)=280.633kNFactor of safety against sliding=280.633174.151The section is safe against sliding=1.61>1.25

&F&A&RPage &Pdesigns:Effective spandesigns:0.42 + 0.025 (25 mm projection in Bed block)

SEISMICCALCULATION OF SEISMIC FORCESah=Horizontal seismic coefficient=(z/2) (Sa/g)(R/I)z=Zone factorfor zone2=0.1I=Importance factor=1.2R=Response reduction factor=1Sa/g=Average response acceleration coefficient=2.5=(0.1/2)x2.5=0.15(1/1.2)av=Vertical seismic coefficient=0 for zone2 & 3AT SILL LEVEL1. Self weightNo.L x B x unit weightWt/mLeverMoment About Heelarm10.3x2.537x2519.05.0996.80221.03x0.30x257.73.6728.20530.5x0.28x1.619x224.92.4411.99440.3x1.62x2210.72.7128.95250.7x1.62x2224.92.7167.55560.5x0.55x1.619x229.82.4423.98370.50x0.28x1.619184.02.9811.98480.28x2.83x1814.13.3246.63890.82x4.45x1866.04.13272.245Total161588.400Horizontal force=161.2x0.15=24.18KnHorizontal moment=588.4x0.15=88.26KnmStress at Toe=+67.546kN/m2Stress at Heel=-67.546kN/m22.DeadloadTotal Dead load from Superstructure=4950.000kNSeismic coefficientah=0.150Seismic force F'=4950x0.15=742.5KNF1=742.5/2=371.25kNSeismic force perRM=371.25/14.4=25.781KN/mEccentricity of the above force e=2.166+0.0752=1.1205mfrom top of bearing.Moment due to seismic force F'=831.97125KN-mat bearing levelChange in vertical reaction=831.97125/21=39.62kNat one supportChange in reaction per RM=39.62/14.4=2.75KN/MMoment at sill level=25.781x4.109=105.93515625KN-mStress at Toe=+81.073kN/m2Stress at Heel=-81.073kN/m2b) Change in vertical reaction of DeadloadChange in reaction per RM=2.7513888889kNe=0.18M=0.49525KN-mStress=P/A + or - M/Z=2.7513888889+0.495252.801.3066666667Stress at heel=1.361656746kN/m2Stress at toe=0.6036210317kN/m23.Stress due to live loadMaximum Live load coming over the span=1000.000KNSeismic force F' per span=1000x0.15=150.0kNSeismic force F' per support=150/2=75.000KNlever arm for seismic force from bearing level=2.166+0.075+1.2=1.7205m2Moment due to seismic force( at bearing level)=129.038KN-mSeismic force at bearing level=75.000kNMoment due to seismic force( at sill level)=308.175KN-mMoment due to seismic at sill level/RM=308.175000000001/14.4=21.401KN-mStress at Toe=+16.378kN/m2Stress at Heel=-16.378kN/m2With live load on spanTotal stress=67.546+81.073+1.362+0.5x16.378=158.169656746kN/m2Without live load on spanTotal stress=67.546+81.073+1.362=149.980656746kN/m2AT FOUNDATION LEVEL1. Self weightNo.L x B x unit weightWt/mLeverMom. About B.O.Farm10.3x2.537x2519.07.19136.76021.03x0.30x257.75.76944.34930.5x0.28x1.619x224.94.8123.66240.3x1.619x2210.74.8151.39150.7x1.62x2224.94.81119.91360.5x0.55x1.619x229.84.5444.62870.5x0.28x1.619184.05.0820.43080.3x2.83x1814.14.9469.54190.82x4.451866.04.54299.613Total161810.290Horizontal force=161.167x0.15=24.17505KnHorizontal moment=810.29x0.15=121.544KnmStress at Toe=+121.544/4.86=25.009kN/m2Stress at Heel=-=25.009kN/m22.DeadloadTotal Dead load from Superstructure=4950.000Seismic coefficientah=0.150Seismic force F'=4950x0.15=742.5kNF1=742.5/2=371.25kNper supportSeismic force perRM=371.25/14.4=25.781kN/mEccentricity of the above force e=2.166+0.0752=1.1205mfrom top of bearing.Moment due to seismic force F'=831.97125kN-mChange in reaction=831.97125/21=39.62kNChange in reaction per RM=39.62/14.4=2.7513888889kN/mMoment at foundation level=25.78x (6.209 )=160.08kN-mStress at Toe=+32.94kN/m2Stress at Heel=-32.94kN/m2b) Change in vertical reaction of DeadloadChange in reaction per RM=2.751kNe=1.3066666667mM=3.595kN-mStress=P/A + or - M/Z=2.7513888889+3.59514814815.404.86Stress at heel=1.2492588782kN/m2Stress at toe=-0.2302259564kN/m23.Stress due to live loadMaximum Live load coming over the span=1000.000kNSeismic force per span=150.000kNSeismic force F'=1000x0.15/ 2 x 14.4=5.2kN/mper supportMoment due to seismic at foundation level=5.208x(4.109+2.09999999999999)=32.336KN-mStress at Toe=+6.654kN/m2Stress at Heel=-6.654kN/m2With live load conditionTotal seismic moment=121.544+160.076+3.595+0.5x32.336=301.3831653981KN-MTotal horizontal force=24.175+25.781++0.5x5.208=52.5603KNWithout live load conditionTotal seismic moment=121.544+160.076+3.595=281.62kN-mTotal horizontal force=24.175+25.781=49.956kN-mWith live loadTotal stress=25.009+32.937+0.5x6.654=61.04kN/m2Without live loadTotal stress=25.009+32.937=57.946kN/m2

&F&A&RPage &PRefer Cl 219.5.1.1/ IRC -6_2010shirley: for PCC as per table 8- IRC 6_2010shirley: as per table 6-IRC 6-2010Refer Cl 219.5 IRC 6_2010