降低不稳直顶缓倾斜中厚矿床采掘比的途径

圆柱切底全面崩落法和长柱切底全面崩落法,适合开采不稳直顶缓倾斜中厚矿体。前者的主要开采特点是:先在矿层下盘以留圆柱的房柱法切底回采,然后向上钻凿平行炮孔,崩落上部矿体。长柱切底全面崩落法与前者的主要区别在于以长柱代替圆柱,它适用于倾角较大和岩矿稳定性较差的条件。两种方法均具有生产能力高,采掘比低,贫化损失较小,改善通风条件等优点。

Ways to cut development ratio of unstable direct-roof, gently-inclined and medium thick orebody

Cylindrical floor-cut full-caving methods and long-pillar bottom-cut full-caving methods are designed to extract unstable direct-headed,gently-inclined and medium thick orcbodies. The former features the under wall of the ore bed being extracted floor-cut by room and pillar mining method with residual cylindrical pillars before parallel blastholes arc drilled upwards to collapse the upper orebody. The major dif-feernce between these two methods lies in long-pillars in place of cylindrical pillars, suited to the conditions of greater dip angle and poor stability of orebody.The both methods enjoy advantages of higher production capacity, lower development ratio,less dilution loss and better ventilation.