Evaluation of the Critical Nature of Flaws in Plastic Pipeline Gas Distribution Systems

摘要

A material testing program was undertaken to establish basic material properties for a high density, high molecular weight polyethylene. Fracture tests were conducted on laboratory specimens to study the fracture process and to provide data for development and verification of analytical fracture models. Linear plane stress and plane strain cohesive fracture models were investigated. These models were assessed by making qualitative and quantitative comparisons between measured and predicted rates of slow stable crack growth. The qualitative predictions of the model were in agreement with observed behavior. The nonlinear material behavior precluded making good quantitative comparisons. Recommendations for further research are made.