Sheet1MOMENT DISTRIBUTIONINPUT DATA151516.41840LENGTH OF BOX (ft )16.416.4WIDTH OF BOX ( ft )16.4HEIGHT OF BOX ( ft )15TOP SLAB THICKNESS (in )18BOT m. SLAB THICKNESS ( in )15SIDE WALL THICKNESS ( in )2NO. OF SIDE WALL9.843FILL HEIGHT ( ft )2SURCHARGE HEIGHT ( ft)30IMPACT FACTOR (% ) ( EXP. SLAB )0IMPACT FACTOR (% ) (CONC. SLAB )16REAR WHEEL LOAD ( kip )30ANGLE OF FRICTION (degree)4NO OF WHEELOUTPUTWidth of box L=16.4ftHeight of box H=16.4ftTop slab thickness Tt=15inBot.slab thickness Bt=18inSidewall thickness St=15inFill height Fh=9.843ftSurcharge height Sh=2ftUnit weight of concrete UC=150Ib / ft3Unit weight of soil US=120Ib / ft3Angle of friction O=300Co-efficientKa =(1- SIN O)/(1+SIN O)=0.33maxM Effective width=7ftMoment of inertia(Top slab)I1 =(b*Tt3 )/12=0.163ft4(bot. slab)I2 =(b*Bt3)/12=0.281ft4(Side wall)I3 =(b*St3)/12=0.163ft4(Side wall)I4 =(b*St3)/12=0.163ft4Stiffnessk1 =I1 / W=0.0099ft3k2 =I2 / W=0.0171ft3k3 =I3 / H=0.0099ft3k4 =I4 / H=0.0099ft3Distribution factorD1 =k1/(k1+k3)=0.50D2 =k3/(k1+k3)=0.50D3 =k2/(k2+k3)=0.63D4 =k3/(k2+k3)=0.37LOAD CALCULATIONDEAD LOAD( a )Top slab load( i ) SW =(b * Tt /12) * UC187.5( ii) Fill weight =((Fh *1) * US)1181.16Total load=1368.66( b )Bottom slab load( i ) SW =(b * Tb /12) * UC225( i ) SW =(b * Tb /12) * UC225( ii) From topslab =(Sw top slab)187.5( ii) From topslab =(Sw top+Fill)1368.66(iii) From vert.wall = (n*St*H*UC)375(iii) From vert.wall = (n*St*H*UC)37512*W12*WTotal load=788Ib/ ftTotal load=1969Ib/ ft( c )Side wall loadEarth pressure (at top ) =Ka * Y * H0Earth pressure (at bottom ) =Ka * Y * H656Ib / ftLateral load due to surcharge =Ka *Y*Sh'80Ib / ftLateral load due to fill=Ka *Y*Fh394Ib / ftLIVE LOADTop slab load :-Effective width (exposed slab) =(4 + 0.06 * S) ==calculated f ) =39.04%Asd =0.190in2/ft =0.402mm2/mm6.TEMP. & SHRINKAGE REINFORCEMENT :-( i ) Ast = 0.0025*b*t =0.3in2/ft =0.635mm2/mm( ii ) Ast = 0.0018*b*t =0.22in2/ft =0.457mm2/mm7.REINFORCEMENT FOR CRACKING MOMENT :-Acr =0.657in2/ft =1.392mm2/mm

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TWO VENT BOX CULVERTTWO VENT BOX CULVERT DESIGN :-CALULATION :-( ft )( m )1313FILL HEIGHT3.2811.00LOAD CALCULATIONUnit weight of concrete UC=150Ib / ft313Unit weight of soil US=120Ib / ft312.58DEAD LOAD( a )Top slab load( i ) SW =(b * Tt /12) * UC162.51313( ii) Fill weight =((Fh *1) * US)393.72Total load=556.22Ib/ ft15.8415.84( b )Bottom slab load( i ) SW =(b * Tb /12) * UC162.5INPUT DATA( ii) From topslab =(Sw top+Fill)556.2260000fy FOR NORMAL STEEL ( psi )(iii) From vert.wall = (n*St*H*UC)1773500f 'c FOR CONCRETE ( psi )12*2*W42.65LENGTH (ft)Total load=896Ib/ ft3.281FILL HEIGHT ( ft )Reduce SW of botm slab load =162.5Ib/ ft14.76WIDTH OF BOX (ft )So total upward load of bot.slab=733Ib/ ft11.50HEIGHT OF BOX ( ft )( c )Side wall load13TOP SLAB THICKNESS (in )13BOT m. SLAB THICKNESS ( in)Earth pressure (at top ) =Ka * Y * H0(Triangular)13VERT. WALL THICKNESS ( in )Earth pressure (at bottom ) =Ka * Y * H755Ib / ft(Triangular)14DISTn BETn WHEEL ( ft )Lateral load due to fill & surch. =Ka *Y*Fh317Ib / ft( UDL)0IMPACT FACTOR8NO OF REAR WHEELLIVE LOADRWL =16kip4NO OF FRONT WHEELFWL =4kip2SURCHARGE HEIGHT (ft)Top slab load :-0.50ACTIVE EARTH PRESS. COEF98.60NEffective width (exposed slab) =(4 + 0.06 * S) =