Concrete target quasi-static resistance to a penetrating projectile considering the material constitutive relationships

Abstract

The well-known Forrestal's semi-empirical approach for a rigid projectile penetration into s thick concrete targets is based on an empirical term of the target quasi-static resistance that is calibrated from test data and is assumed to depend on the concrete uniaxial compressive strength.The present paper aims at deriving a theoretically based method for determining the quasi-static resistance term that is independent of test data. Considering the triaxial state of stress in the target around the projectile and the high magnitude of stresses and associated large deformations, the target material is described by an arbitrary non-linear pressure–volumetric strain relationship and a non-linear pressure dependent shear strength plasticity envelope.The major advantage of the new proposed approach is the theoretical sound basis and the clear dependence on the constitutive properties of the concrete target. The deceleration and penetration depth time histories obtained using the calculated theoretical value of the quasi-static resistance term are compared with measured data and very good agreement with test data is observed. Major parameters of the equation of state and of a shear strength plasticity envelope are investigated to clarify their effect on the magnitude of the quasi-static resistance term.