Projectile penetration of reinforced concrete considering the effect of steel reinforcement: Experimental study and theoretical analysis

In this study, experiments in which projectiles penetrated into plain and reinforced concrete targets were conducted by controlling single variables for a differential experimental design including projectile impact locations, reinforcement arrangements, reinforcement buried depths, and reinforcement bonding conditions. Based on cavity expansion theory and the dynamic response analysis of the steel reinforcement, a reinforced concrete target penetration resistance model was established. The accuracy of the model was verified using the experimental data, and the influence of the steel reinforcement arrangement on projectile penetration was analyzed. The results show that the reinforcing steel bonding effect exert an indirect resistance while the impact of the projectile with the reinforcement exert a direct resistance, which is different from direct penetration into concrete. The indirect and direct resistances against the projectile act to reduce penetration depth and target surface damage. The results calculated using the derived numerical method clearly describe the observed details of the projectile impact with the steel reinforcement, and are in good agreement with the experimental data. The indirect and direct resistances of the steel reinforcement were observed to be affected by the initial conditions of the projectile and the target including impact locations and reinforcement arrangements. It was found that increasing the reinforcement ratio and adopting a denser reinforcement arrangement can reduce the penetration depth of projectile, and better protecting the integrity of the target.