Microscale Study of Geomembrane-Geotextile Interactions

This paper summarizes the results of a study that used quantitative measures of surface roughness as the basis for investigating the role of topography on the interface shear mechanism of geomembrane-geotextile interfaces. The results show that the interface strength and mechanisms can be quantitatively related to the surface roughness of the geomembrane. The peak and residual interface strengths increase dramatically through the use of textured geomembranes. For textured geomembranes, the peak interface strength is due to the micro-texture of the geomembrane, however, the residual interface strength is primarily attributed to macro-scale surface roughness that pulls and breaks the filaments of the geotextile. The effect of geomembrane wear on the stress-strain response is quantified. The findings of this study provide a quantitative framework that can lead to a significantly improved basis for the selection of geotextiles and geomembranes in direct contact.