Dynamic response of fully-clamped steel plate under laboratory-simulated sequential fragment impact and blast loading

Abstract

Composite projectile (CP) impact, as a new in-laboratory experimental technique, was further developed to simulate sequential fragment impact and blast loading generated by cased charge explosion. New developments include modification of the equivalent relationships between main loading characteristics from the explosion and the CP impact and the improvement of the experimental setup. Then, it was used to study the dynamic response of a fully-clamped steel plate under simulated sequential fragment impact and blast loading. For comparison, a widely used traditional technique, which decoupled the two load types by generating pressure pulse on the structure with pre-formed holes to simulate the sequential loading, was also employed. Deformation processes, deformation/failure modes, and central deflections of the plates tested using the two different techniques were compared and analyzed. It was found that the traditional technique underestimated the damage caused by sequential fragment impact and pressure pulse: the plate subjected to the CP impact was found to be more susceptible to tearing fractures at high impact velocities. Finite element simulations were subsequently performed and the simulation results were validated against experimental data. The validated FE model was then employed to further evaluate the synergetic effects of sequential fragment simulating projectile (FSP) impact and impulsive loading on the ballistic performance and deformation behavior of the fully-clamped steel plate. Results indicate that while pressure pulse in the sequential loading leads to an enhanced ballistic limit of the plate, FSP impact in the sequential loading causes significant local shear and tensile deformation around the perforation, resulting in plate tearing at a lower impact velocity.