Behavior of High-Strength and Ultrahigh-Performance Concrete Targets Subjected to Relatively Rigid Projectile Impact

Abstract

This experimental study was conducted to evaluate the impact behavior of relatively rigid projectiles with conical and hemispherical nose shapes on normal to high-strength and ultrahigh performance concrete (UHPC). For this impact experiment, target specimens with dimensions of 200×200×100 mm and concrete compressive strengths of 35, 80, 100, 120, and 150 MPa were used. The test results showed that as the concrete strength increased, the penetrability of concrete normalized by the kinetic energy of each projectile decreased, and its declining slope decreased. As to projectiles, the conical nose shape achieved greater penetration depth for normal-strength concrete, but the difference between that and hemispherical projectiles with respect to high-strength concrete and UHPC was minuscule. To verify the validity of existing impact equations for the design/evaluation of normal-strength concrete, high-strength concrete, and UHPC walls, the existing equations were compared with the test results. The 2017 Hwang et al. equation predicted the penetration depth quite well regardless of the concrete strength because the equation accounts for energy absorption of the nose of a projectile upon collision. Research results provided insight into the design and evaluation of high-strength concrete or UHPC walls subjected to high-velocity impact.