Mechanical performance of polystyrene foam (EPS): Experimental and numerical analysis

In this work, we perform a series of tests to characterize the mechanical properties of polystyrene foam (EPS), including uniaxial compression tests, uniaxial tension tests and three point bending tests. EPS exhibits a ductile to brittle transition when the loading mode changes from compression to tension. The elastic modulus in tension is nearly one order larger than that measured in compression. The digital image correlation (DIC) technique is used to measure the strain distribution. A homogenous deformation can be observed in uniaxial deformation tests, where EPS exhibits a near-zero Poisson's ratio. For the three point bending tests, DIC can capture the strain localization behavior of specimens with a prefabricated crack. Based on the experimental observations, a simple phenomenological model is developed and further implemented for finite element analysis. The simulation results show reasonable agreement with experimentally measured strain distribution in the bending tests.