Influence of Confinement Boundary on Damage of Concrete Targets Under Hypervelocity Impact

Concrete is widely used as fundamental building construction material for both civilian and military purposes. However, because of the limits of experimental facilities and computational capability, the semi-infinite target was usually replaced by one with finite dimension. To clarify the boundary influence on the damage of concrete targets impacted at hypervelocity, we have investigated the stress wave propagations and damage features in targets with four types of confinement boundaries by method of numerical simulation. Results show that the shock compression produces the initial complete damage region around the perforation. The tension of two main stresses engenders more damage to the finite targets with no restriction. For cracks in other three targets, shear stress may play the main role. Simulation results indicate that the restriction of iron hoops might be the cause of transverse fracture. The sleeve made of appropriate hard material instead of hoops may be a better boundary confinement.