直眼掏槽爆破中大直径中空孔作用机理研究

Mechanism Research of the Effects of Empty Hole in Parallel Cut Blasting

在直眼掏槽爆破中,空孔的存在有着重要意义。通过对大直径空孔在掏槽爆破中的作用机理理论分析研究,得出其主要作用有三:一是引起空孔周边的爆炸应力集中,具有导向爆破裂隙发展的作用;二是空孔为其它装药掏槽炮孔增加了一个辅助自由面,利于孔壁应力波的反射拉伸作用,增强槽腔内岩石的破碎,并为破碎后岩块提供了运动导向和膨胀移动空间;三是造成空孔与装药槽孔间的岩石的剪切作用,进一步加强岩石破坏。

In cut blasting, the presence of empty hole has important significance. Through the theoretical analysis of the mechanism, it is concluded that the empty hole has three main functions： first, it can cause the explosion stress concentration, lead to the orientation of blasting crack development; second, the empty hole adds a free surface to other charging cutting holes, strengthens the hole wall stress wave reflection effect, enhances groove cavity rock crushing, and provides the guidance for the broken rock and expansion mobile space; third, the sheafing action between empty hole and the charging cutting hole further strengthen the rock damage.