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Modeling the penetration and perforation of concrete targets by rigid projectiles

We present an analytical approach for the penetration and perforation processes of concrete targets by rigid projectiles. We first derive an empirical relation for the penetration resistance (Rt) of thick concrete targets to rigid projectiles, in terms of their unconfined compressive strength (fc) and the projectile’s diameter (D). We then develop an analytic model for the perforation process of concrete slabs by accounting for their back surface, through a reduced resisting stress (Reff) which the slab exerts on the rigid projectile. With these values of Reff, we calculate the ballistic limit velocity (Vbl) for a given projectile/slab configuration, as well as the residual velocities (Vr) of a perforating projectile. Predictions from our model are compared with several sets of published data, showing good agreement.