Experimental and theoretical study on steel long-rod projectile penetration into concrete targets with elevated impact velocities

Abstract

To have a better understanding of behaviors of projectiles and concrete targets during impacts at different velocities, experiments and analysis of medium carbon steel long-rod projectiles impact on concrete targets have been carried out in this paper. The impact mechanics of projectiles and concrete targets has been investigated for impact velocities in range of 500 m/s to 1700 m/s covering three penetration regimes. Based on the observation of the residual projectiles and penetration depths, a deforming model has been proposed to investigate the deformable process of projectiles. Furthermore, deforming penetration model was established based on a rigid penetration model and the projectile deformation parameters, which was validated by the experimental results. The applicability of existing eroding penetration models penetration into concrete were validated and discussed based on the experimental results. At last, the eroding penetration model was further justified and improved by taking the deforming penetration regime into consideration. Influence of projectile and target strength on penetration process were investigated based on the theoretical model. Results show that the crater diameter and depth are linearly proportional to the impact velocity, while the volume of the crater and the initial impact kinetic energy of the projectile have a linear relationship. The calculated diameters of residual projectiles and Depth of Penetration (DOP) with a board range of impact velocities are in good agreement with experimental results. It is noted that the strength of projectiles and concrete targets have significantly influences on DOPs and critical velocities.