Comparative Study on Settlement of EPS Road Embankments by Numerical Method

The material of EPS is polystyrene resin, produced by polymerizing styrene monomer which is created by oil refining. Polystyrene resin is made by adding a foaming agent to beads or pellet-shaped polystyrene. EPS has two types: expanded polystyrol (EPS) and extruded polystyrol (XPS), utilizing different manufacturing processes. EPS produced by a foam molding process and XPS produced by an extrusion foaming process. Especially, the EPS construction method was applied to reduce the settlement of soft ground for the highway embankment. However, EPS geofoam has been little known as a construction material for transportation structures in Vietnam. In this study, numerical modeling of the EPS geofoam embankment using the finite element method (FEM) through PLAXIS 2D software was carried out. In the analyses, the hardening soil model (HS) was also used to model the grounds and EPS geofoam. Additionally, the interface elements were used to simulate the slippage between the blocks of EPS geofoam with two distinct densities, i.e., 0.2, 0.24 kN/m3. The analyzed results indicated that EPS geofoam is an effective method to diminish the settlement influence of highway embankments on soft ground.