Failure analysis of semi-infinite concrete targets subjected to tubular projectiles impact

Improving the penetration efficiency of missiles into concrete is a practical research topic. In this paper, a tubular projectile was designed to enhance penetration diameter on concrete targets. To validate numerical simulation methods, an experiment of an ogive-nosed projectile penetrating a semi-infinite concrete target was reproduced by numerical simulation. Based on the validated numerical model, the penetration progress of a tubular projectile into a semi-infinite concrete target was analyzed. By assessing the penetration tunnel diameter and depth, the effects of key parameters, i.e., the wall thickness (15.0, 30.0, 60.0, 90.0, 120.0 mm) and velocity (400.0, 600.0, 800.0, 1000.0, 1200.0, 1400.0 m/s) of tubular projectile on penetrating concrete targets have been investigated in detail. Furthermore, the penetration performances of flat-nosed projectiles and tubular projectiles on concrete targets with the same mass were compared. The results indicate that with the increase in the wall thickness and velocity of the tubular projectiles, the penetration depth of the projectiles into the concrete target increases gradually, and the increase in the diameter of the tunnel is not obvious. In the case of the wall thickness of the tubular projectile which is greater than or equal to 30.0 mm, the concrete core, near the head of the tubular projectile, is completely fractured and separated from the concrete target. When the flat-nosed projectiles have the same mass and length with tubular projectiles, the diameter of the tunnel caused by the tubular projectile on the concrete targets is always much larger than that caused by the flat-nosed projectiles. The difference of them can be 60.5%. In the condition that the flat-nosed projectiles have the same mass and diameter with tubular projectiles, the depth of the tunnels caused by tubular projectiles in the concrete targets is always much larger than that caused by flat-nosed projectiles. The difference of them can be 95.6%.