LIFETIME PREDICTION OF PE100 AND PE100-RC PIPES BASED ON SLOW CRACK GROWTH RESISTANCE

Papers # 2016 Berlin

Due to the high slow crack growth resistance of modern polyethylene pipe grades a reliable lifetime assessment of pipes with focus on stage II failure has become challenging. The current paper presents a scientific approach for a fracture mechanics lifetime prediction based on Cyclic Cracked Round Bar (CRB) Tests. Based on this standardized tests (ISO 18489) a more sophisticated concept enables the determination of SCG rates which is necessary for development of material laws based on fracture mechanics. In combination with practically proven boundary conditions and modern numerical models this concept is able to predict the stage II failure of a PE100 and a PE100 RC pipe grade in relatively short time.

Related keywords : Polyethylene, lifetime, cracks, slow crack growth, material testing.
Please note that the whole article content is available on PPCA website onlySource : 2016 Berlin


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