Mr. Fayaz KhakiDate: September 21, 2015Page 2

Project

Design verification of CNR Baldonnal Jack and Bore pipe

NORTHERN INTERIOR REGIONFORT ST. JOHN DISTRICT OFFICECROSSING AND ENCROACHMENT PERMITSFOR CROSSING UNDER CN RAIL (APPROX MARKER 724.5)NEAR BALDONNEL ROAD & 255 RDFORT ST. JOHN, BC

Table of Contents

Table of Contents2List of Figures2Assumption:3Dead load Calculation:3Live load Calculation:4Impact load:4Total load:4Check for through Wall Bending:4Check for through Wall Bending:5Recommendation:6

List of Figures

Figure 1: Plan of Jack and Bore pipe3Figure 2: Sectional details of Jack and Bore pipe6

Assumption:Dry density of soil, = 120 pcfWater table is below the pipe level.Yield strength of pipe material= 350 MPa.Modulus of soil reaction, E =2500psi [Manual of Guidelines for the design of buried steel pipe, July 2001]Bending constant, K = 0.1 [Manual of Guidelines for the design of buried steel pipe, July 2001]Deflection lag factor, D1 =1.5 [Manual of Guidelines for the design of buried steel pipe, July 2001]Frost depth is considered at 2.3m [Provided by the client] So the depth of the fill soil above the pipe is = 2.3m

Figure 1: Plan of Jack and Bore pipeDead load Calculation:Earth Dead load pressure on the conduit, Pv = C [Manual of Guidelines for the design of buried steel pipe, july 2001]

=120x (2.3x3.281) psf =905 psf=6.28 psiWater table is considered lower than the pipe line.C= depth of soil cover above pipe= (2.3x3.281)=7.54ftLive load Calculation:

The pressure transmitted to the pipe from rail load, = 11.63 psi [Table 4.1-2 of Manual of Guidelines for the design of buried steel pipe, july 2001Cooper E-80 load is considered with impact factor 1.5 for at a depth 6ft.Impact load:Impact load factor is required 1.35 (For more than 3 ft depth for railway road as per American railway Engineering association) Total load:Total applied force on the pipe= 6.28+11.63X1.35 =21.98 psiCheck:The moment of inertia of pipe per inch of circumferences is the moment of inertia of the strip 0.375 wide and 1 long, I= (1/12) x1x (0.375) ^3 =0.00439 in4/in

Ovality , = = 0.0145[Manual of Guidelines for the design of buried steel pipe, July 2001]D= pipe out side diameter=24K= bending constant= 0.1 y= Vertical deflection of pipe, inchesD1=Deflection lag factor =1.5P = total load on pipe=21.98 psiE= modulus of soil reaction, psi =2500psi (assumed)(EI)eq= equivalent pipe wall stiffness per inch of pipe length. In/lbCheck for through Wall Bending:

Through wall bending stress due to ovalization, E= modulus of elasticity of the pipe,t= thickness of the pipeD= outside diameter of the pipe.bw=4x29x106x0.0128x.375/24= 26421 psiThis should be less than .5y= 0.5x 50750 psi= 25375 psi [[Manual of Guidelines for the design of buried steel pipe, July 2001]Status: not OKRe Calculation with thickness 0.5 inchThe moment of inertia of pipe per inch of circumferences is the moment of inertia of the strip 3/8 wide and 1 long, I= (1/12)x1x(0.5)^3 =0.0104 in4/inCheck:

Ovality , = = 0.010D= pipe out side diameter=24K= bending constant= 0.1 y= Vertical deflection of pipe, inchesD1=Deflection lag factor =1.5P = total load on pipe=21.98psiE= modulus of soil reaction, psi =2500psi (assumped)(EI)eq= equivalent pipe wall stiffness per inch of pipe length. In/lbCheck for through Wall Bending:Through wall bending stress due to ovalization, bw=4x29x106x.010x. 5/24= 24363 psi.< 25375 psi. OKThis should be less tha .5y= 0.5x 50750 psi= 25375 psi.Status: OKRing Buckling from LoadsAllowable pressure for ring buckling

Empirical coefficient of elastic support , B = = 0.25C= depth of the soil cover above the pipeD= outside diameter of the pipe

Critical Stress on pipe, Pc = [Manual of Guidelines for the design of buried steel pipe, July 2001]Rw= water bouncy factor= 1.0E= 2500 psiFS= 2.5(EI)eq= 29X106X0.0104 (Considering 0.5 inch thickness) =301600

Pc ==264 psiCompressive load =21.98 psi< Pc . OKStatus: OKRecommendation:From the above calculation it is recommended that the thickness of the jack and bore 600mm diameter steel pipe is 0.5 or 12.5mm is required.

Figure 2: Sectional details of Jack and Bore pipe