孔距、排距对高台阶抛掷爆破抛掷率的影响

为了研究高台阶抛掷爆破中是否也存在最优的间、排距,在黑岱沟露天煤矿进行了大量现场试验,试验结果表明:在黑岱沟露天矿高台阶抛掷爆破中,排距不变,孔距增大.爆堆的前沿抛距基本不变,抛掷率随着炮孔密集系数的增大而增大.当m>1.6时,抛掷率开始下降.与孔距相比,排距变化对抛距的影响程度要大一些.在高台阶抛掷爆破中确实存在有利于抛掷的最佳间、排距,只是因为试验的台阶高度、单耗等参数的不同,最佳m值存在差别.在黑岱沟露天矿特定的试验条件下可以认为,当1.45

Effect of Casting Parameters on the Cast Percentage of High Bench Cast Blasting

To search the optimal row and column spacing for high bench cast blasting, experiments have been done at Hedaigou open pit. The results show that, for the high bench cast blasting particularly at Heidaigou, when the hole (column) spacing increases with fixed row spacing, the forefront throw-distance of muck-pile is almost the same. The cast percentage increases with the increase of hole density m, but it declines after m >1.6. The influence of row spacing on the throw-distance is bigger than that of hole spacing. Experiments also reveal that. To reach the best cast percentage, there exists optimal row and column spacing, which depends on the specific conditions of the testing bench, explosive charge and other parameters. At Hedaigou open pit, the value of optimal m could be the one between 1.45 and 1.55, depending on the particular experimental conditions.