ARCHIVED REPORTS_2001_2 - Laserfiche WebLink

Home Browse Search

rI Page I Project: Forward Landfill Project Number. By: RMG Date: 9/5/01 Check Date: Description: Leachate Collection Pipe Loading_ Purpose: Determine if the selected leachate collection pipe has adequate strength. Pipe Specs: Slotted HDPE pipe with the following characteristics is propsed for use: Diameter = 6 inches DR = 7 Slot Width = 0.1 inches Slot Spacing = 1.1 inches o.e. Landfill Data: Max. height = 200 feet Waste density = 48.15 pcf 1300 Calculations: Loading of flexible pipes is analyzed using the Iowa Deflection Formula: % deflection = D1 * KP(100) / (0.149 * F / delta Y + 0.0611- 1) where: Allowable % deflection for HDPE pipe = 1.75 0.149 * F / delta Y = 2 * E/ (3 * (DR -I)^3) = 410.49 D l = Deflection Lag Factor = 1.5 (Sharma&Lewis) K - ]Bedding Constant = 0.083 (Sharma&L.ewis) P =Pipe Loading in psi: waste height*density /144= 66.9 F / delta Y = Pipe Stiffness in psi E I = Modulus of Soil Reaction in psi 3000 (Sharma&Lewis) E = Modulus of Elasticity of Pipe in psi = 133000 (Shatma&T ewis) DR = Dimension Ratio of Pipe = OD / t = 7 % def lecl 9.4 ,not allowing for a reduction in pipe strength due to slots. Effect of Sloffing A method of evaluating the impact of pipe slots on the strength of the pipe is to reduce the stength of a unit length of pipe by the cumulative width of slots within the unit length. 'This method is conservative as it neglects the contribution of the pipe material remaining at Slot locations. U a a o a o a o — No strength is assumed for this ring of the pipe_ Reduction in strength = slot width / slot spacing = 0.090909 percent Reduced stregth term ( 0.149*F/delta Y) of Iowa Equation = 373.18 % defieei 1.5 , considering a reduction in pipe strength due to slots. Conclusion: The specified pipe is: Acceptable j; tools\pipeloadU"4I.xlsSheetl