Centrifuge Modeling and Instrumentation of Geogrid-Reinforced Soil Barriers of Landfill Covers

An experimental program was conducted to investigate the influence of geogrid as a reinforcement layer within the soil barrier of a landfill cover system under various levels of distortion. Centrifuge model tests were performed at 40 g on soil barriers subjected to continuous differential settlements using a 4.5 m radius beam centrifuge having a capacity of 2,500 g-kN available at IIT Bombay. Differential settlements were induced using a motor-based differential settlement simulator designed for a high gravity environment. Marker-based digital image analysis was adopted to estimate strain distribution along the geogrid layer and in the soil along the soil-geogrid interface at the onset of differential settlements. Various sensors, such as miniature pore pressure transducers, linear variable differential transformers, and strain gauges, were used to measure the water breakthrough, deformation profiles of the soil barrier, and the mobilized tensile load of model geogrids, respectively. Centrifuge model test...