Influence of Explosive Shape on the Response of Steel Plates under Blast Loading

In the protective engineering field, close-range explosions produce more energy and are more likely to cause severe damage to building structures than long-range explosions. In current standards, close-range explosions are defined as an explosion with a scale distance of less than 1.2 m/kg1/3. Besides, the steel plate's dynamic response is critical, especially under the blast loads generated by different shapes of explosives. For cylindrical explosives most commonly used in military and engineering, this study carried out experimental and numerical simulation studies on steel plates under the close-range air blast loads generated by different H/D cylindrical explosives (0.5 <= H/D <= 3.0). First, close-range air blast load tests were performed to study the failure modes of steel plates at different scale distances. The height-to-bottom diameter H/D ratio was defined as the shape factor of cylindrical explosive, and the effect of H/D on the failure deformation and dynamic response of the steel plate was quantitatively studied. Finally, the characteristics of shock waves generated by cylindrical explosives with different H/D were analyzed to determine the influence of H/D on the spatial distribution of shock waves. The results showed that with the increase of H/D, the steel plate deformation and damage gradually decreased. When the scale distance was more significant than or equal to 0.38, there was no crack in the steel plate, and the residual deflection gradually reduced with the increase of H/D. Despite the different scale distances, the residual deflections showed similar trends with increasing H/D. When the scale distance was less than or equal to 0.30, the steel plate cracked, and the crack area gradually decreased with increased H/D.