Validation of an Accelerated Fracture Mechanics Extrapolation Tool for Lifetime Prediction of PE Pressure Pipes

摘要

For a fracture mechanics lifetime assessment of pressurized polyethylene (PE) pipes the knowledge of the material specific creep crack growth (CCG) kinetics is essential. As testing of CCG with common test methods is not possible in feasible times, an accelerated extrapolation procedure based on fatigue tests with cracked round bar (CRB) specimens was developed previously. Within the present work this test procedure was used to characterize CCG of a PE material at elevated temperatures of 60°C. In combination with a numerical simulation model for pressurized pipes, lifetimes were predicted and correlated to real pipe failure times of the same material.