Laboratory investigation of shear behavior of high-density polyethylene geomembrane interfaces

Abstract

As a product of polymeric materials, geomembranes (GMs) are widely used in engineered systems as impervious barriers due to their low permeability. In this study, a large-scale composite shear test apparatus was developed to investigate the shear behaviors of various GM interfaces. A series of direct shear tests were conducted on GM-soil, GM-geotextile, and GM-concrete interfaces. Two types of high-density polyethylene (HDPE) GMs, a smooth GM and a textured GM, were used to evaluate the effect of GM-texturing on the shear properties of these interfaces. Based on the experimental data, the friction angles and adhesions of GM interfaces were calculated using the Mohr-Coulomb criterion. Test results describing the behavior of GM-soil and GM-geotextile interfaces from the current study were then compared with results from previous studies. The test results are shown to verify the reliability of the new large-scale composite shear apparatus. In addition, this paper presents preliminary experimental results of the GM-concrete interface shear tests.