重复爆炸条件下岩石介质破坏效应试验研究

EXPERIMENTAL RESEARCH ON ROCK BREAKAGE EFFECT UNDER REPEATED EXPLOSIONS

为了探索精确制导武器对岩石介质中地下防护工程实施重复打击后的毁伤效应问题,进行重复钻孔爆炸和一次性钻孔爆炸对比试验。试验结果显示:在装药总量相等条件下,二次钻孔爆炸所形成的爆坑直径与一次性钻孔爆炸所形成的爆坑直径近似相等,但爆坑深度和破碎区范围却分别是一次性钻孔爆炸的2倍和1.66倍。量测结果显示:试验中二次钻孔爆炸与一次性钻孔爆炸相同测点处峰值应力相差较大,相同测点处二次钻孔爆炸的峰值应力远高于一次性钻孔爆炸的峰值应力。计算结果显示:一次性钻孔爆炸的应力衰减指数为1.933,应力波传播速度约为4800m/s。最后根据应力波传播机制推算得出:在装药总量相等条件下二次钻孔爆炸所需防护层厚度是一次性钻孔爆炸所需防护层厚度的1.07倍。

In order to explore the breakage and damage effect problems of the underground protective engineering in rock under repeated penetration and explosion by precision guided weapons,the contrastive experiments of single-time drilled explosion and secondary drilled explosion have been accomplished. The experimental results show that the explosive crater diameters by secondary drilled explosion and single-time drilled explosion respectively are approximately equal,but the depth and the breaking range of explosive crater of the former is 2 times and 1.66 times of the later under equal total amount of charge. The measure results show that the peak pressures have a large difference at the same measuring points,and the peak pressures of the secondary drilled explosion are higher than those of the single-time drilled explosion for the same measuring points. The calculation results show that the pressure damped exponential of single-time drilled explosion is 1.933,and the stress wave velocity is approximately 4 800 m/s. The conclusions,which has been obtained by calculation according to the stress wave propagation mechanism,shows that the requested thickness of protective layer for secondary drilled explosion is 1.07 times of that for single-time drilled explosion under equal total amount of charge.