Shock attenuation by porous materials

Shock waves from explosions can do great damage to humans, buildings and other structures. Protective measures may therefore be useful to attenuate the effect of the shock waves. Porous materials have traditionally been considered to be good at shock mitigation and could possibly be placed in front of an object that requires protection from shock waves. An initial literature survey of various shock attenuation experiments is carried out, showing apparently contradictory results regarding the mitigation effect of different materials. In order to investigate this, a theoretical and numerical study of the shock wave attenuation phenomenon was performed. The study showed that the experimental design largely determines the results. Porous materials can reduce the shock wave amplitudes, but at the expense of longer wave duration. In some cases, protective materials (in particular porous ones) can actually increase the maximum load on the object that is to be protected. In a given case where something requires protection, expert analysis is necessary to ensure that any mitigation measure does not have the opposite effect.