Dynamic Behavior of Aluminum Plates Subjected to Sequential Fragment Impact and Blast Loading: An Experimental Study

Abstract

This paper presents a study on the dynamic behavior of thin aluminum plates subjected to consecutive fragment impact and blast loading. To this end, two separate experimental setups are used. In the first setup, 2 mm thick aluminum plates EN-AW-1050A-H24 were subjected to the ballistic impact of fragment-simulating projectiles (FSPs). Experiments were carried out for FSP calibers of 7.62 mm and 12.7 mm considering both single impact and triple impacts with variations in the spacing of the impact locations. The out-of-plane displacement and in-plane strain fields were measured using digital image correlation (DIC) coupled to a pair of high-speed cameras in a stereoscopic setup. In the second setup, a subsequent blast loading was applied to the perforated plates using an explosive-driven shock tube (EDST). After the plates are perforated, the strain field around the holes depended on the caliber, the impact orientation of the FSP, and the distance between the impact locations. When the blast loading was applied, cracks tended to appear in areas of strain concentration between the perforated holes. It was found that the relative distance between the holes significantly influences the target’s response mode.

Special Issue on Explosion Effects in the Built Environment

“…Real-world explosions are often not just air-blast events but involve the detonations of encased explosives or explosives buried within another medium. Atoui et al [3,4] conducted two studies into the influence of air-blast loading and their projectile impact.…”

“…In the first study [3], impact and blast are applied separately, showing that regions of plates with impact perforations rupture more readily under blast loading. The second study [4] is able to capture the essential features of a shrapnel bomb at the laboratory scale by detonating C4 with embedded ball bearings, producing controllable combined blast and fragment loading on a downstream target plate. These experiments were modeled to gain further insights into combined blast and projectile impact loads, extending the dataset beyond the experimental range.…”