炸药的选择虽然有些采石场可利用散装铵油炸药,但英国大多数采石场的孔底装药或孔底和柱状装药,均采用卷装高威力炸药。在地下水位以上的浅部台阶采用大直径炮孔的露天矿,大量采用铵油炸药是可能的,这样,可以提供更大的膨胀能形成松散的爆堆。目前大直径炮孔趋于用更高的爆速 The Choice of Explosives Although some quarries can utilize bulk ammonium explosives, most of the UK quarries have bottom-hole and column-bottom charges, most of which are packaged with high-powered explosives. It is possible to use large quantities of ammonium explosives in open pit mines with large boreholes at shallow steps above the groundwater level, thus providing greater expansion to form a loose blast. At present large-diameter blasthole tends to use a higher detonation velocity