Analysis on Rear Face Crater-forming of Projectile Penetrating Limited-Thickness Concrete Target
JI Chong1,2，LONG Yuan1，GAO Zhen-Ru1，ZHOU Wang-yuan3
1. PLA University of Science and Technology, Nanjing 210007, China2. National Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 10081, China3. Unit No. 75735 PLA, Guangzhou 410800, China
Abstract：Experiments on the projectile penetrating limited-thickness concrete target prove that the concrete chunks spall off from the rear face target and the conical crater forms in the process of penetration. The determination of the cone crack angle θ in a concrete target subjected to a projectile impact is important when assessing the level of the damage in the target. The perforation failure of concrete slab is simplified as a problem of punching. By the twin-shear stress three-parameter strength criterion and rigid-plastic model, an axisymmetrical failure mechanism is given and the failure envelope of stress circle is found to be two straight lines. Then the value of θ is obtained. The research shows that θ is controlled by the ratio of compressive strength to tensile strength. Based on theoretical analysis, the approach to improve anti-perforation performances of the targets by adding steel-fiber into concrete is proposed. Ballistic experiments are performed by using a Φ12.7mm ballistic gun. The experiments show that the quantity and scattering angle of the target debris are decreased largely. The study has showed that steel-fiber reinforced concrete with high deformed steel-fiber volume fraction is effective on anti-perforation.
2013, Vol. 32 
