Experimental Scrutiny of Uniaxial Compressive Stress-Strain Relationship for Expanded Polystyrene Concrete

The application scope of expanded polystyrene (EPS) concrete is continuously expanding because of its excellent thermal insulation ability and light weight. Research on EPS concrete has mainly focused on its strength and thermal insulation performance. In order to perform finite element analysis of the EPS concrete structure, it is necessary to investigate not only the relationship between the strength, density, and admixture but also the uniaxial compressive stress-strain curve and Poisson's ratio. Herein, the stress-strain curves and other mechanical parameters were obtained by a uniaxial compression test of EPS concrete prismoid specimens with densities of 1000-1600 kg/m(3). Based on the experimentally observed data, the effects of dry density, fly ash content, and sand content on the strength, elastic modulus, and stress-strain curve of EPS concrete were methodically investigated. The results show that the strength-density curve is in the form of a power function. Meanwhile, the strength decreased by approximately 15% and 13% with the addition of 10% fly ash and 10% sand, respectively. Furthermore, the elastic modulus increases with an increase in density such that the corresponding curve is approximately linear. Finally, the variation law of the uniaxial compressive stress-strain relationship curve associated with EPS concrete was analyzed. The results revealed that the mechanical behavior of EPS concrete is quite different from that of ordinary concrete. This study provides a convenient approach for the finite element analysis of prefabricated light steel-EPS concrete composite structures.