HDPE Geosynthetics: Premature Failures and Their Prediction Available to Purchase

Most manufactured products and engineering works perform satisfactorily. Those that do not, fail at an unexpected defect not because of a gross miscalculation of basic service life. It is necessary to identify such unexpected failure-initiating defects and to understand at what size such defects become critical and at what rate induced cracks will propagate. HDPE is an engineering thermoplastic that has been used in geotechnical and civil engineering applications for many years as natural gas distribution pipes, waste containment geomembranes, and soil reinforcement. The predominant mode of premature failure of HDPE pipe and geomembrane is a quasi-brittle fracture initiated at stress concentrating surface notch geometries and/or unexpected point stresses. Such failures occur due to the fundamental stress cracking susceptibility of HDPE. The semi-crystalline, microstructure of HDPE, which is responsible for its excellent chemical resistance and strength properties, is also responsible for its susceptibility to stress cracking. The characteristics of stress cracking in pipe and geomembrane are reviewed and extended to geogrids. An overview of the test methods used to assess the mechanical durability of HDPE is presented together with methods used to relate accelerated test results to service lifetimes. Such methods may also be appropriate for geogrids.