Resistance of composite target against combined effects of large caliber projectile penetration and successive charge explosion

Abstract

Attributed to the high strength, hardness, and ductility, the armor steel, ceramic, and ultra-high performance concrete (UHPC) have great potential applications in the critical protective structures to resist the impact and subsequent blast load of Earth Penetrating Weapons (EPWs). This study presents an experimental and numerical study to quantitatively evaluate the resistance of the composite structures consisting of the above three materials under the preceding large-scale caliber projectile penetration and successive charge explosion. Firstly, the combined tests of 105-mm-caliber projectile penetration and the successive 5 kg TNT explosion on the benchmark normal strength concrete (NSC), armor steel/UHPC, and armor steel/SiC ceramic/UHPC composite targets were conducted, respectively. The superiority of the armor steel/UHPC composite structure is proved in terms of the final destructive depth, crater dimension as well as projectile integrity. Then, for reproducing the destructive depth and crater dimension of concrete, the Holmquist-Johnson-Cook (HJC) model for concrete was modified in terms of tensile damage, strain rate effect, and Lode-angle dependence. By utilizing the restart algorithm and the modified concrete model, the combined projectile penetration and charge explosion test was reproduced, and the adopted finite element analyses approach, modified constitutive model, and parameter values were validated. Besides, the penetrated hole method is validated reliable and recommended by comparisons with the prefabricated hole method. Finally, the destruction effects of a full-scale EPW on NSC, UHPC, and armor steel/UHPC composite targets were evaluated through two ballistic efficiency factors, and the optimal configuration is confirmed.