Behavior of expanded polystyrene (EPS) blocks under cyclic pavement foundation loading

Abstract

This study introduces a mechanism for initial assessment and further development to improve understanding of EPS behavior as a super-lightweight material for road construction. Large scale cyclic plate load tests on model pavements were performed. The effect of several factors including thickness of soil, thickness of subsequent EPS layers and density of EPS on the surface deformations, resilient modulus (Mr) and interlayer pressure transfer were investigated. The results indicated that compared to a covering soil layer of 300 mm, the rut depth on the loading surface reduced by 13.5% and 40.8% when the soil thickness was increased by 33% and 100%, respectively. With a constant soil thickness, increasing the thickness of an upper (denser) EPS layer with respect to a bottom (softer) EPS layer, from 200 mm to 600 mm, would only result in a 20% decrease in the peak settlements at the loading. Resilient modulus of the system was found to be dependent on soil thickness and a designer can choose an appropriate resilient modulus assuming the soil-EPS composite acts as subgrade or subbase. In order to extend the results to a wider range of geofoams, soils and layer thicknesses, a simple stress analysis method was also trialed.

Study on Dynamic Modulus and Damping Characteristics of Modified Expanded Polystyrene Lightweight Soil under Cyclic Load

“…In the past, many quantitative studies have been carried out on the physical and static characteristic of EPS lightweight soil, including compressibility, permeability, unconfined compressive strength (UCS), shear strength, California bearing ratio, stress-strain behavior, etc. [16][17][18][19][20][21][22]. The results show that the increase in EPS particle content (EC) reduces the density of EPS granular lightweight soil, and at the same time leads to the decline of various strength indexes and deformation properties of EPS granular lightweight soil [23,24].…”

Experimental and Numerical Verification of the Railway Track Substructure with Innovative Thermal Insulation Materials

“…At present, as thermal insulation or reinforcement materials in sub-ballast or sub-base layers can be used various polymer materials e.g., expanded polystyrene (EPS) [ 8 ], polyurethane [ 9 ], extruded polystyrene (styrodur) [ 10 , 11 , 12 ], artificial aggregates, liapor with foam glass [ 13 , 14 ], and geosynthetic materials (geogrids, geo-mattresses) [ 15 , 16 ]. The expanded polystyrene (EPS) in contact with subsoil is also used as isolation under (shallow) foundation [ 17 , 18 ] and under road pavement foundation [ 19 ]. The installation of the XPS/EPS plates does not generate any chemical leaking and cause groundwater contamination, but these solutions are not ecological (polystyrene is difficult to recycle).…”