The objective of this research is to evaluate the static and dynamic interface strengths of the soil-geomembrane- geotextile interfaces found in typical liner systems. This objective will be accomplished by performing extensive torsional ring shear tests on the various liner interfaces. A ring shear apparatus will be used instead of a direct shear or pullout apparatus to allow for large continuous shear deformation in one direction, constant cross- sectional area during the test, thinner soil specimens permitting faster drainage and a residual strength in better agreement with field case histories.
