常见例句By alternately disposing along vein and underwall outside-vein raises and designing new structures for runoff tracks,rib pillars can be stoped in step with chambers. 简述了官地银金矿传统浅孔留矿采矿法应用中存在的突出问题,即间柱滞后矿房回采,且占有矿量多,造成地压集中显现。 返回 underwall