Influence of the explosion center on shock wave propagation in a confined room

It is well established that the knowledge about shock wave propagation in the free field cannot be applied to confined environments, especially when it comes to predicting the reflected shock wave. With the increase in accidental or intentional detonations of explosives in confined or urban environments, it is important to study and thoroughly understand the propagation of shock waves to provide behavior prediction tools. The present research focuses on understanding the influence of a variation in the explosion center in a confined room and how this variation affects the shock wave propagation and the reflection due to the confined environment. The shock waves were generated by the detonation of a stoichiometric hemispherical charge of propane-oxygen mixture. The charge was placed in a small-scale model (Hopkinson's scaling law) which represents a typical room in a building. The model was equipped with 29 pressure sensors distributed on the walls and the floor to record pressure history data. The aim of this study was to determine experimentally the evolution of the shock wave parameters such as the maximum overpressure or the arrival time and to predict the origin of the first three reflected peaks with the help of a simple and fast tool.