Load bearing analysis of EPS-block geofoam embankments

Abstract

This paper presents a deformation-based load bearing analysis procedure that utilizes the elastic limit stress, i.e. the compressive stress at 1 percent strain, to design expanded-polystyrene (EPS)-block geofoam for roadway embankments. The procedure consists of determining the maximum vertical stress from dead and traffic loads at various levels within the EPS fill mass and selecting an EPS type that exhibits an elastic limit stress that is greater than the calculated vertical stress at the depth being considered. The higher the required elastic limit stress, the greater the required block density. However, the cost of EPS block increases with increasing density. Therefore, an advantage of the recommended deformation-based design procedure is that the calculation of stresses and strains within the EPS mass allows the selection of the type of EPS blocks to be optimized by selecting blocks with a lower density for the lower portions of the embankment and the higher density blocks for the upper part of the embankment. The selection of EPS blocks with the lowest possible density yields a cost efficient EPS block geofoam embankment.