Liquefaction Response of Geofoam Reinforced Sand

Liquefaction, which is an earthquake hazard caused by undrained cyclic loading, is a phenomenon where a significant portion of the soil’s shear resistance is lost as a result of a rise in pore water pressure and starts flowing like a dense liquid. Many studies have been carried out in literature to understand the concept of liquefaction in soils and various mitigation techniques. Expanded polystyrene (EPS) geofoam inclusions in geotechnical constructions have gained significant popularity and attention in recent times. EPS geofoam is considered a suitable alternative to conventional sand and gravel backfill materials in geotechnical structures like retaining walls and roads, as it has several beneficial effects like reduction in vibration amplifications due to excellent damping properties and mitigating possible failure because of its significantly low unit weight. Most of the research on geofoam-reinforced soils is focused on characterizations, damping, cyclic loading properties, and shear strength changes. There are no studies available on the liquefaction response of geofoam-reinforced sand. The present study tries to understand the cyclic loading response and liquefaction potential of sand specimens with geofoam inclusions through cyclic simple shear tests. Main findings of this work highlight the efficiency and capability of EPS geofoam in reducing the excess pore water pressure during cyclic loading and hence help in mitigating liquefaction.