EPS Resistance Factors and Applications on Flexible Walls

Cantilever retaining walls with lengthy free heights are usually required in several geotechnical applications. Compacted soil is the typical backfill behind such walls, yet soil has high unit weight that imposes large lateral loads and may lead to wall outsized dimensions. Expanded polystyrene (EPS) or Geofoam can substitute the soil backfill due to its lightweight and high compressibility, and can reduce the lateral static loads imposed on walls. In this paper, the EPS main parameters were measured after conducting a series of laboratory tests to determine the mechanical and interface properties. Also, a reliability analysis was conducted to calibrate the partial resistance factors for the EPS mechanical properties. Then, a flexible cantilever retaining wall with EPS inclusion was modeled using finite element. From the main outcomes, the lateral pressure was significantly reduced after using the EPS inclusion by up to 75%.