A fracture mechanics approach for the prediction of the failure time of polybutene pipes

In this work two grades of Isotactic polybutene-1 with a different degree of isotacticity have been investigated; fracture tests have been performed at various temperatures and testing speeds on DCB and SENB samples. Optical methods have been used to record crack advancement. s of the tests have been interpreted using the fracture mechanics framework; a time–temperature superposition scheme has been adopted to describe crack propagation behaviour over several decades of time-scale. An analytical model has been applied to predict the lifetime of pressurised pipes from experimental fracture data. There is good agreement between model predictions and experimental data obtained from full-scale tests on real pipes.