接近冰层爆破漏斗试验及其理论分析

FIELD EXPERIMENTS AND THEORETICAL ANALYSIS ON BLASTING CRATERS OF ICE LAYERS BY NEAR CHARGE

通过现场爆破漏斗试验和鼓包运动过程观测,系统分析了以水为约束介质的冰层在接近药包爆炸的破坏过程.证明在接近药包爆炸加载时的冰层破坏主要是爆炸气体膨胀形成的多次加载水介质所产生的破坏作用,并且表现出明显的脆性破坏特征,其裂隙的破坏范围也随着冰的强度和脆性的提高而增大.根据现场试验结果得出：当冰层的厚度为0.26～0.65m时,以水为约束介质的最佳爆破作用系数K=a/Rw=1.8～2.2;冰层下药包接近爆炸的最佳炸药单耗是冰层内药包爆破的1/2.

The breakage process of ice layers under loaded of explosive＇s energy of a near charge confined with water was systematical discussed in terms of the many observable results of blasting craters field experiments and their face displacements in field blasting. It is proved that ice layers＇ breakage was mainly come from the expanded actions of explosive pressurized gas and also reflected obviously brittle failure characteristics and, the region of broken fissures generated by blasting are expanded with the increasing of ice layers＇ strength and brittleness. It is brought forward that the most optimum blasting impacted coefficients （a/Rw） is 1.8～ 2.2 by a near charge confined with water at the condition of ice thickness being 0.26～0.65m and, the most optimum values of explosive consumed amount per unit by a near charge beneath ice layers is only 1/2 of one by a charge in ice layer according to the experimental results.