Calculation of Coupled Stress and Seepage for Dams with a Geotextile/Geomembrane Composite Liner Available to Purchase

A geotextile/geomembrane composite liner was placed on the upstream slope of the clay core between the core and rock-fill shoulder to prevent seepage through a rock-fill dam at Zhushou reservoir in China. The paper investigates the coupled effects of stress and seepage on the performance of the rock-fill dam. Using numerical examples it is demonstrated that the tensile stiffness and tensile strength of the geotextile/geomembrane composite liner modifies the distributions of stress, strain and displacement in the dam. Two different models of the geotextile/geomembrane composite liner are examined. One model treats the composite liner as a linear elastic element and the second as a contact element which can account for relative slippage at the interfaces between the dam core, the composite liner and the rock-fill shoulder of the dam.