Performance and evaluation of an EPS plate to mitigate blast on underground protective structures

Explosions due to terrorist attacks or accidents can cause severe damage to critical infrastructure. To protect important facilities from explosion damage, they can be constructed belowground. Further, an explosion mitigation layer can be used to provide additional protection. In this study, an expanded polystyrene (EPS) plate has been incorporated into the soil layer for blast mitigation, and the performance of the system has been investigated experimentally. The results indicate that there is an optimum ratio of sand layer thickness and EPS plate thickness for decreasing and dispersing blast pressures. Formulas describing the peak pressure and scaled impulse on the bottom of the mitigation system as functions of a scaled distance from directly under the explosion source and scaled layer thickness have been derived.