Penetration Mechanism Of Reinforced Concrete Targets By Tandem Warhead

Tandem warhead is one trend of the development of anti-concrete warheads, which is composed by the precursory shaped charge and the following kinetic energy projectile (KE projectile). The most damage effect of the tandem warhead is determined by the matching parameters of two stages. Many factors such as shaped charge penetrating reinforced concrete, KE projectile penetrating the pre-damage concrete, the relationship of depth and diameter of the precursory penetrating crater, the launch of the following KE projectile are researched in this paper by theory analysis, experimental research and numerical simulation.Following aspects are included in this paper:1. The mechanism of shaped charge penetrating reinforced concrete is researched. Continuous model of shaped charge jet penetrating reinforced concrete is set up. It is applied to analyze the influence on depth and diameter of some parameters, such as velocity grads, radius of jet and stand-off. It is validated E/V criterion byproduct. An engineering model of eroding JPC penetrating concrete is set up on the basis of conservation of mass and momentum. And it's proved valid by experiment. Numerical simulation of formation process and penetration process of three typical shaped charge jets has been carried out to get the parameters. The result show that X Charge has high performance which can get large diameter and high depth hole in penetration, and the experiment of X-charge penetration reinforced concrete is completed successfully. X-charge is suitable precursory of tandem warhead.2. The mechanism of KE projectile penetrating the pre-damage concrete is researched. A model of KE projectile with various head shape to pre-damage concrete is set up on the basis of modified cavity expansion theory. How the pre-damage concrete crater's geometrical parameter and strength weakening degree of damaged zone affect the penetration effect is deeply researched. When the velocity of the following KE projectile is constant and the diameter of pre-damage crater exceeds 0.7 times as the diameter of the KE projectile, the penetration depth is markedly enhanced and the influence of the crater .shape to the penetration depth is more significant. The influence of various hypotheses about strength weakening of the damaged zone to the penetrating depth is analyzed, and the linear weakening hypothesis is proved to be more close to the reality. Grey pri-estmation model of maximum penetration depth of the KE projectile is established. The results of this paper are in good agree with the Mostert and Folsom experiments. The precision of the model is higher than that of Teland model. The process of KE projectile penetrating the pre-damage concrete target is simulated by using LS-DYNA. The theoretical analysis is confirmed with numerical simulation results.3. The penetrating model of the tandem warhead and the matching relationship of the precursory shaped charge and following KE projectile are researched in this paper. An optimized method for the matching design of the diameter and the maximum penetration depth is set up by analyzing the penetrating process of the tandem-penetrating warhead. The effect of precursory detonation wave on following KE projectile is analyzed. One-dimension shock wave spreading model is set up. The formula of velocity...