Laserfiche WebLink
U <br />C7 <br />Page i <br />Project: Forward Landfill By: RMO Date: 9/5/01 <br />Project Number. Check: Date: <br />Description: Leachate Collection Pipe Loading _ <br />Purpose: Determine if the selected leachate collection pipe has adequate strength. <br />Pipe Specs: Slotted HDPE pipe with the following characteristics is propsed for use: <br />Diameter= 6 inches <br />DR = 7 <br />Slot Width = 0.1 inches <br />Slot Spacing = 1.1 inches o.c. <br />Landfill Data: Max. height = 200 feet <br />Waste density = 48.15 pcf 1300 <br />Calculations: Loading of flexible pipes is analyzed using the Iowa Deflection Formula: <br />% deflection = Dl * KP(100) / (0.149 * F / delta Y + 0.061 El) where: <br />Allowable % deflection for HDPE pipe = 1.75 <br />0.149 * F / delta Y = 2 * E/ (3 * (DR- 1)^3) = 410.49 <br />D I = Deflection Lag Factor = 1.5 (Sharma&Lewis) <br />K - Bedding Constant = 0.083 (Sharma&Lewis) <br />P = Pipe Loading in psi: waste height*density /I44= 66.9 <br />F / delta Y = Pipe Stiffness in psi <br />E I = Modulus of Soil Reaction in psi = 3000 (Sharma&Lewis) <br />E = Modulus of Elasticity of Pipe in psi = 133000 (Sharma&Lewis) <br />DR = Dimension Ratio of Pipe = OD / t = 7 <br />% deflect 1.4 ,not allowing for a reduction in pipe strength due to slots. <br />Effect of Sloifing <br />A method of evaluating the impact of pipe slots on the strength of the pipe is to reduce the <br />stength of a unit length of pipe by the cumulative width of slots within the unit length. This <br />method is conservative as it neglects the contribution of the pipe material remaining at <br />slot locations. <br />a o a o <br />--- No strength is assumed for this ring of the pipe. <br />Reduction in strength = slot width / slot spacing = 0.090909 percent <br />Reduced stregth term ( 0.149*F/delta Y) of Iowa Equation = 373.18 <br />% deflect 1.5 , considering a reduction in pipe strength due to slots. <br />Conclusion: The specified pipe is: Acceptable <br />j:\tools\pipeloadU-oadl.xisSheaI <br />