Relaxation Behavior of Thermally-Induced Stress in HDPE Geomembranes

A series of stress relaxation laboratory experiments have been performed on high density polyethylene (HDPE) geomembranes, where the stress was induced by temperature changes. It was found that for practical rates of temperature decrease, the tensile stresses were for the most part relaxed as they were applied. Therefore, very little stress relaxation occurred (even for times up to one week) after the final lower temperature was achieved. This experimental finding has some practical implications for the installation of geomembranes in the field.