煤矿硬岩巷道掘进大直径炮孔爆破试验研究

增大药卷直径可提高炸药爆速,配以较大直径炮孔爆破能够增强岩石的破裂和破碎。为了提高煤矿硬岩巷道掘进爆破效率,在液压凿岩台车施工巷道首次进行大直径炮孔和大直径药卷中深孔爆破试验研究,同时对各段雷管起爆延期时间进行优化,其中第2段雷管的延期时间由原先的25 ms增加至50 ms,目的是使掏槽爆破后岩石有足够的时间破碎、运动和抛掷出槽腔,形成新的自由面。并配用底部集能装药掏槽爆破技术和水垫层周边光爆装药结构,爆破试验取得了良好的效果。

Large Diameter Hole Blasting Experimental in Hard Rock Roadway of Coalmine

Large diameter explosive charge can improve blasting velocity and destroy rock much efficiently combined with large diameter hole.To improve blasting efficiency in hard rock roadway in coal mine,the mid-deep hole blasting testing with large diameter hole and large diameter cartridge are carried out in construction roadway.Meanwhile,the detonating delay time is optimized from the original 25 ms to 50 ms for the section 2,which supplies enough time for rock breaking,moving and new free face producing.Good blasting effect is achieved by using power concentrated charge structure at hole bottom coupled with water cushion scheme.