On the penetration of semi-infinite concrete targets by ogival-nosed projectiles at different velocities

Abstract

Concrete has been widely used to construct protective structures in both civil engineering and defense installations which may be subjected to impact by projectiles at different velocities. In this paper, a theoretical study is presented on the penetration of a semi-infinite concrete target by an ogival-nosed projectile at different velocities within a unified framework. Depending upon impact velocity V0, the projectile may behave as rigid or quasi-rigid (with mass loss due to abrasion), deformable and erosive. The projectile penetrates the concrete target either in a rigid or quasi-rigid mode when V0 is less than rigid body velocity (VR) or in an erosive mode when V0 higher than hydrodynamic velocity (VH) or in a deformable mode when VR ≤ V0 < VH. The rigid body velocity is determined to be the impact velocity at which dynamic strength of the penetrator times the cross-section area of the shank is equal to the current resultant target resistance force as the projectile nose shape changes from ogival to blunt; the hydrodynamic velocity is estimated to be the impact velocity at which a stable mushrooming head is formed on the basis of physical consideration. It transpires that the present model correlates well with available experimental data for concrete penetration.