柱形装药爆炸破坏混凝土的数值模拟分析

Numerical simulation of cylindrical charge damaging concrete medium

利用LS-DYNA有限元程序建立计算模型,对有无预制孔的半无限混凝土介质中柱形装药的爆炸破坏过程进行了数值模拟研究,得出了不同埋深时的爆腔半径和爆破漏斗半径以及毁伤混凝土的最佳埋深范围,结果与理论计算吻合较好。同时,计算分析了在一定埋深处正向起爆与反向起爆的破坏状态,并对计算结果进行理论分析,结果表明反向起爆更有利于混凝土的破坏。

In this paper, the damaging process of semi-infinite concrete medium with and without predrilled cavity under explosion of cylindrical charge is numerically simulated using LS-DYNA program. Radiuses of blasting crater and blasting funnel at different depths are obtained, which suggests that crater radius is approximately constant under certain depth and funnel radius increases first and then decreases as depth increases. The optimum depth range for damaging concrete target is also given, which are in good agreement with the results of theoretical analysis. Meanwhile, the results demonstrate that predrilled cavity intensifies the damaging effects and enlarges optimum depth range of cylindrical charge, which provides theoretical basics for anti-hard warhead. At last, the damaging process of direct and indirect initiation at certain depth are also simulated and theoretically researched, which proves that indirect initiation can promote the rate of energy employing and produce more damaging effects than direct initiation. Hence, indirect initiation is a better choice for damaging concrete medium.