Penetration and internal blast behavior of reactive liner enhanced shaped charge against concrete space

Penetration and internal blast behavior of reactive liner enhanced shaped charge against concrete space were investigated through experiments and simulations. The volume of the enclosed concrete space is about 15 m³. The reactive liner enhanced shaped charge utilizes reactive copper double-layered liner, which is composed of an inner copper liner and an outer reactive liner, while the reactive material liner is fabricated by PTFE/Al (Polytetrafluoroethylene/Aluminum) powders through cold-pressing and sintering. Static explosion experiments show that, compared with the shaped charge which utilizes copper liner, the penetration cavity diameter and spalling area of concrete by the novel shaped charge were enlarged to 2 times and 4 times, respectively. Meanwhile, the following reactive material had blast effect and produced significant overpressure inside the concrete closed space. Theoretical analysis indicates concrete strength and detonation pressure of reactive material both affect the penetration cavity diameter. To the blast behavior of reactive material inside the concrete space, developing TNT equivalence model and simulated on AUTODYN-3D for analysis. Simulation results reproduced propagation process of the shock wave in concrete space, and revealed multi-peaks phenomenon of overpressure-time curves. Furthermore, the empirical relationship between the peak overpressure and relative distance for the shock wave of reactive material was proposed.