Abstracts Category : Other

Effect of Time on Soil-Geomembrane Interface ShearStrength

by Saeed Kloofah Alzahrani

In the past thirty years, geosynthetic materials havebeen used widely in various civil engineering applications due totheir numerous advantages. Geomembranes are one of the most commongeosynthetics that are used primarily as an impervious boundary forliquids or gases. High density polyethylene (HDPE), the materialused for geomembranes, shows a viscoelastic behavior to the appliedloads over a period of time in the form of creep or stressrelaxation. Effect of time on soil-geomembrane shear strength iscritical factor that should be studied carefully, becausesoil-geomembrane interfaces usually form weak planes and may causefailures. A series of large direct shear tests were carried out inthe laboratory to investigate the effect of time onsoil-geomembrane interface shear strength. The geomembrane sampleswere placed under a sustained load for two weeks then the sheartests were performed. The test results showed that the interfacefriction angle increases with time due to further penetration ofsoil particles into the geomembrane, resulting in the increase ofsoil-geomembrane contact areas. This thesis presents the testsperformed, results obtained, discussion of the results, findings,and recommendations for future studiesAdvisors/Committee Members: Bilgin, Omer (Committee Chair).