SymbolsReferenceCalculationOutputAcArea of concreteAccArea of concrete in compressionAsArea of tension reinforcementAs minMinimum area of tension reinforcementavLength of that part of member traversed by shear failure planebWith (breath) or effective width of sectioncCover to outer diameterdEffective depth of sectionFcBasic force used in defining compressive forcesFtBasic force used in defining tie forcesfcuCharacteristic strength of concretefsEstimated design service stress in the tension reinforcementfyCharacteristic strength of reinforcementGShear modulusHMaximum horizontal forceHxHorizontal force in x directionHyHorizontal force in y directionhOverall depthKELKnife edge loadLCritical perimeterlxDimension of element on x directionlyDimension of element on y directionlzDimension of element on z directionMDesign ultimate resistance momentMxMoment on x axisMyMoment on y axisMzMoment on z axisqSurcharge loadrInternal radius of bendSLSServiceability limit stateTTraction forcetThickness of the elementULSUltimate limit stateVShear force due to design ultimate loads or design ultimate value of aconcentrated loadvDesign shear stressvcDesign shear stress in concretexNeutral axis depthx'Distance from Y axis to the centroid of an elementy'Distance from X axis to the centroid of an elementzLever armz'Distance from X - Y plane to point where the considered resultantforce actingCoefficient, variously defined, as appropriateStrain in tension reinforcementNominal range of movementSoil friction angle, or diameterActive earth pressureUnit weight of soilPartial load factorPartial load factorDoc. No.DECDESIGN UNITDesignedDateEPC DIVISIONCheckedDateCENTRAL ENGINEERING CONSULTANCY BUREAU (CECB)Job CodePageReferenceCalculationOutputDoc. No.DECDESIGN UNITDesignedDateEPC DIVISIONCheckedDateCENTRAL ENGINEERING CONSULTANCY BUREAU (CECB)Job CodePageReferenceCalculationOutputDoc. No.DECDESIGN UNITDesignedDateEPC DIVISIONCheckedDateCENTRAL ENGINEERING CONSULTANCY BUREAU (CECB)Job CodePageReferenceCalculationOutputDoc. No.DECDESIGN UNITDesignedDateEPC DIVISIONCheckedDateCENTRAL ENGINEERING CONSULTANCY BUREAU (CECB)Job CodePageReferenceCalculationOutputDoc. No.DECDESIGN UNITDesignedDateEPC DIVISIONCheckedDateCENTRAL ENGINEERING CONSULTANCY BUREAU (CECB)Job CodePage

Box Culvert DesignCalculationOutputShear Stress in tapered BeamFigure 01Point LoadF=0.00kNDistributed Loadw=0.00kNho=3.63mx=6.52mL=22.81mb=1.00mz=22.81my=8.33mShear ForceV=3597kNBending MomentM=16019kN.m1104.7942779936ypC.Shear-11.830.0000.000.00030.4700.00011.0400.000.00-9.861.972-42.931.78830.4700.54311.040-42.9369.66x.ho=23.67m-7.284.551-69.644.12530.4701.25411.040-69.64141.64-4.737.100-63.276.43530.4701.95611.040-63.27191.49hz=h0/L*{L+(x-1).z}0.0011.83434.9610.72530.4703.26011.04034.96227.97hz=23.67m4.7316.567245.5415.01630.4704.56411.040245.54191.497.2819.116405.4517.32630.4705.26611.040405.45141.64D=2*h0.{L+(x-1).z}/(3L)9.8621.695600.4219.66330.4705.97711.040600.4269.66D=15.78m11.8323.668772.0221.45130.4706.52011.040772.020.00p=hz/2+y=20.16mComplimentary Shear Stress=480.63kN/m2( With Shear,V )1/a=(x-1)/{L+(x-1).z}=0.037Effective ShearV*=V-(1/a).M=3002.43kNComplimentary Shear Stress=401.18kN/m2(with Effective Shear, V* )Ceylon Electriity BoardDoc. No.Dam SafetyDesignedDateEnvironmentalCheckedDateCivil Structure MaintananceJob CodePageCalculationOutputCeylon Electriity BoardDoc. No.Dam SafetyDesignedDateEnvironmentalCheckedDateCivil Structure MaintananceJob CodePageCalculationOutput2 -Vertical Live LoadsFor Fill Depths H 8 feet (2400 mm) and Culvert Clear Span Length,The effect of live load is neglected in design when the depth of fill is more than8 feet3 -Hydrostatic Pressure (Internal)q ip=C.h=8.33x22.81=190.01kN/m24 -AnalysisConstant K=h{hs}3=1.00lhwk1=K+1=2.00k3=K+3=4.00k5=2K+3=5.00k7=2K+7=9.00k8=3K+8=11.004.1Load Case -01 Testing Condition4.1.1Hydrostatic Pressure-(Internal)MA=MB=qip.h2.K.k760.k1.k3=1853.6260717787kN.m/mMC=MD=Ma. K8k7=2265.5429766184kN.m/m4.1.2Flexure due to weight of wallWall weight ( G )=hw..hq1=2.G=82047.57kN/m2=1871505.1kN/ml.hwMA=MB=q1.l2.K12.k1.k3=444677.40kN.m/mMC=MD=Ma. K5K=-2223387.01kN.m/m4.1.3Flexure due to weight of Roofq=hs.c=82047.6kN/m2Ceylon Electriity BoardDoc. No.Dam SafetyDesignedDateEnvironmentalCheckedDateCivil Structure MaintananceJob CodePageCalculationOutputMA=MB=MC=MD=q.l212.k1=-1778709.61kN.m/mAddition of moment for Load case 01PositionHydrost-aticfuls- MbWallsRoofWalls + Rooffuls-MbTotal ulsA and B1853.631.42595.08444677.40-1778709.61-1334032.211.4-1867645.09-1865050.02C and D2265.541.43171.76-2223387.01-1778709.61-4002096.631.4-5602935.28-5599763.52Roof mid-Span1853.631.42595.08444677.40**4002096.631.45602935.285605530.353557419.22Base mid-Span2265.541.43171.76****6670161.041.49338225.469341397.223112741.823557419.22Walls middle*1.4-6141.80-889354.81-1778709.61-2668064.421.4-3735290.18-3741431.99-4387.00Table - 01Fixed end mement of the wall for Hydrostatic loadMA=W.LMC=W.L1510=3295.3352387177kN.m/m=4943.0028580765kN.m/mMaximum (-ve) moment=W.L(Where x is 0.45L from C)23.3=-2121.5kN.m/m*Calculation of moment at mid span of walls done by aproximatly by addingmoment transferred to mid span from FEM to the Maximum negative meomentoccurred at 0.45L after moment distribution**Moment at mid span of the wall is calculated by considering full bendingCalculation of midspan moment due to wall loadNiutral axis depth from A=3.80m4.2Load Case -02 Culvert empty and trench filledLateral soil pressurees giving rise to flexture in the structure"q"is the rectanguler pressure and "qep" is the triangular pressure4.2.1Trianguler Pressure,qepMA=MB=qep.h2.K.k760.k1.k3=0.00kN.m/mMC=MD=MA. K8k7=0.00kN.m/mCeylon Electriity BoardDoc. No.Dam SafetyDesignedDateEnvironmentalCheckedDateCivil Structure MaintananceJob CodePageCalculationOutput4.2.2Surcharge on walls,qMA=MB=MC=MD=q.h2.K12.k1=0.00kN.m/m4.2.3Surcharge on Roof ,qrMA=MB=MC=MD=q.l212.k1=0.00kN.m/mAddition of moment for Load Case 2PosotionqepqWalls & Roof(LC-1)Surcharg -e (Roof)Total (Survice)fTotal U.L.S.A and B0.000.00-1334032.210.00-1334032.211.4-1867645.09C and D0.000.00-4002096.630.00-4002096.631.4-5602935.28Roof mid-Span0.000.004002096.630.004002096.631.45602935.28Base mid-Span0.000.006670161.040.006670161.041.49338225.46Walls middle***-2668064.420.00-2668064.421.4-3735290.180.000.00Fixed end mement of the wall due to qepMA=W.LMC=W.L1510=0kN.m/m=0kN.m/mMaximum (-ve) moment=W.L(Where x is 0.45L from C)23.3=0.0kN.m/m4.2Load Case -034.2.1This is load case 02 + Hydrostatic load from Load case 01PosotionL.C.02 (Service)Hydrost. (Service)Total (Service)L.C.02 (U.L.S.)Hydrost. (U.L.S.)Total (U.L.S.)A and B-1334032.211853.63-1332178.58-1867645.092595.08-1865050.02C and D-4002096.632265.54-3999831.08-5602935.283171.76-5599763.52Roof mid-Span4002096.631853.634003950.255602935.282595.085605530.35Base mid-Span6670161.042265.546672426.599338225.463171.769341397.22Walls middle-2668064.42-4387.00-2672451.42-3735290.18-6141.80-3741431.99Ceylon Electriity BoardDoc. No.Dam SafetyDesignedDateEnvironmentalCheckedDateCivil Structure MaintananceJob CodePageCalculationOutput5 -Check on ground safe bearing pressure5.1Load Case -01Hydrostatic Pressure=190.01kN/m2Weight of walls=82047.57kN/m2Weight of Roof + Floor=164095.14kN/m2Total Pressure=246332.72kN/m2Total Pressure>6.52kN/m2hence no tok5.2Load Case -02Weight of walls=82047.57kN/m2Weight of Roof + Floor=164095.14kN/m2Surcharge on Roof=0.00kN/m2Total Pressure=0.00kN/m2Total Pressure06.52kN/m205.3Load Case -03Weight of walls=82047.57kN/m2Weight of Roof + Floor=164095.14kN/m2Surcharge on Roof=0.00kN/m2Hydrostatic Pressure=190.01kN/m2Total Pressure=0.00kN/m2Total Pressure06.52kN/m206 -U.L.S. of FlextureMaximum Moments kN.m/mMemberHoggingSaggingRoof-1867645.09(L.C-01)5605530.35(L.C-03)Walls-5602935.28(L.C-02)-3735290.18(L.C-02)Base-5602935.28(L.C-02)9341397.22(L.C-03)i -SlabsMaximum Moment=24.15kN.m/mCeylon Electriity BoardDoc. No.Dam SafetyDesignedDateEnvironmentalCheckedDateCivil Structure MaintananceJob CodePageCalculationOutput6 -Design Calculation for Box Culvert6.1U.L.S. of FlextureAnalysis was carried out for several load cases of various loadingarrangements to find out the maximum effect on the Box culvertDiameter of main reinforcement=1mmDiameter of secondary reinforcement=1mmSection Thickness=22810mmMaximum Bending Moment=24.15kN.m/mAssume severe environment condition, for driving rainCover=22.81mmEffective depth, d=22810-22.81-0.5d=22787mm=22787mmk=M / (bd2fcu)2=(24.15x106 /(1000x1492x25)=0.0000.950dTake Z as 0.95dZ=0.95d=0.95x22787=21647mm6.1.1Design of main reinforcementAs=M / 0.87fyz=24.15 x106 / 0.87x460x142As req==3mm2/m3mm2/mUseT1@not applicable( As=0mm2/mAs pro=0mm2/mMinimum area of main rainforcement for slabs100As / bad=100x452/(1000x149)=0.0000.13Main r/fT1@not applicable06.2Design for Shear ReinforcementCheck shear in U.L.S. on roof and floor slabsTake Load case 02Shear across support=(0.00-Wt of Base x f )=0kN/m2Therefore shear in the support=0x1.2 /2=0.00kN/mCeylon Electriity BoardDoc. No.Dam SafetyDesignedDateEnvironmentalCheckedDateCivil Structure MaintananceJob CodePageCalculationOutputDesign shear force, V design=0.00kN/mEffective depth, d=22787mmTension steel across shear plane=Y12 -250 c/c100 As/bd=100 x 4521000x149=0.00Effective depth=22787mmvc=0.79x{(100As/bd)1/3.(400/d)1/4/1.25=0Design shear stressv=V/bd=(65.45x103)/(1000x149)=0.00N/mm2v0vc06.3Check in U.L.S. on the ability of the wall to trasmit the axial loadsTreat as a column with bending at right angle to wallCheck h/hw=22.81/22.81=1