孔底起爆对台阶爆破效果影响研究

摘要

Theoretical analysis of the influence of explosive package placement on blasting effect is conducted and the mechanism of the improvement denotation from the end of the hole makes for blasting effect is elucidated .Field tests in mines are analyzed for the comparison of the schemes of denotation in the middle and at the end of the hole , and high speed cameras are used to collect data of the open-pit bench blasting process .After the processing of data by MAS,the curve of the displacement ,casting speed and casting direction of rock blocks from different sections of the bench slope varying with time variables is obtained ,revealing the influence regularities of denotation locations have on rock casting speed and direction and proving the advantage denotation at the end of the hole has in bench blasting .The loading efficiency is increased by 17 %at the bottom of blasted scraps by denotation at the end of the hole ,it being a solution to the insufficient looseness at the bottom of blasted scraps and loading efficiency .%通过起爆药包位置对爆破效果影响理论分析，说明孔底起爆提高爆破效果的作用机理。通过矿山现场试验，对中部起爆方案和孔底起爆方案进行分析，利用高速摄像机对露天台阶爆破过程进行数据采集；MAS软件对数据进行处理后，从台阶坡面最先移动位置，台阶坡面运动轮廓，测点速度随时间变化情况，得到了台阶坡面不同位置的岩块位移、抛掷速度和抛掷方向随时间的变化曲线，揭示了起爆点位置对岩石抛掷速度和方向的影响规律，证明了孔底起爆在台阶爆破中的优越性。孔底起爆使矿山爆堆底部的铲装效率增加了17％，解决了矿山爆堆底部松散性不足，铲装效率低的问题。