Centrifuge modeling of geosynthetic reinforced clay liners of landfills

Abstract

Imperviousness of clay liners is essential in landfills in order to safeguard the environment from contamination. To accomplish this task, the behavior of clay liner of landfills with and without reinforcement inclusion has been explored by carrying out controlled in-flight simulation of nonuniform settlements of landfill in a geotechnical centrifuge using a trap-door arrangement. The reinforcement ability of geosynthetic materials such as geogrid is used to control the crack propagation and permeability of clay liner even at large settlement differences. Centrifuge model test results demonstrate a potential of reinforced clay liners to retain its integrity without significant cracking and crack propagation. Test results have shown that a geogrid layer that is placed within the top portion of the clay liner restrains cracking and enhances the sealing efficiency due to soil-geogrid frictional resistance. The adoption of geosynthetic reinforced clay liner (GRCL) provides an ideal solution for enhancing the deformation capacity. The GRCLs are a promising barrier material for situations in which nonuniform settlements are expected, for example, in landfill capping systems.