Dynamic response of expanded polystyrene concrete during low speed impact

The impact response of lightweight concrete filled with expanded polystyrene beads (EPS concrete) has been studied experimentally using a drop hammer system equipped with a high speed photography system. According to the impact force-time curves and the images of specimen surface obtained during the tests, the impact response of EPS concrete can be summarized as a four-stage procedure. The damage of EPS concrete is found to be a progressive process, which initiates from the upper part and develops downwards, leading to fluctuation of impact force. Based on the experiments, the energy dissipation capability of EPS concrete is evaluated, which demonstrates a dependence on the fracture mode of EPS concrete at the impact velocities in a range of 2-4 m/s. The energy dissipation capacity of EPS concrete is found insensitive to the EPS volume fraction, when it is in a high range from 70.2 to 80.3 vol%. Up to 18.6% increase in energy dissipation is observed in the concrete with 80.3 vol% EPS under impact at 4 m/s.