Long Term Behavior of EPS Geofoam for Road Embankments

In recent years expanded polystyrene (EPS) geofoam has successfully been used to reduce the acting vertical and horizontal stresses in several geotechnical applications due to its light weight, compressibility, and durability. In this study the efficiency of utilizing EPS blocks as a replacement for typical soil embankments under roadways was investigated. Accordingly, a detailed laboratory program was completed to measure the short- and long-term behaviors of EPS, which included unconfined compression (UC) and creep strain (CS) tests based on the time–temperature–stress superposition (TTSS) technique. Loading type applied during testing was cyclic loading to mimic the actual conditions under roadways, while the EPS density used was 35 kg/m³ to minimize deformations. The main outcome of this study was providing measured properties for local EPS considering creep stain after 100 years of cyclic loading, and these properties are ought to provide reliable design for EPS embankments under roadways.