康家湾永久防水矿柱安全开采可行性

Safe Mining Feasibility of Permanent Waterproof Jamb in Kangjiawan Mine

康家湾矿是典型的大型水体下矿床，开采技术条件极其复杂，而留设大量永久防水矿柱，造成资源积压．分析了矿区内主要构造对顶板围岩及含水层影响、顶板与隔水层和相对隔水层位置关系、含水层及勘探钻孔对矿柱回收的影响；计算了冒落带和导水裂隙高度及安全开采深度；用ANSYS有限元软件模拟了空区上覆岩层稳定性及最大允许暴露面积．结果表明，断层不会连通空区与水体，矿柱顶板围岩稳固，与含水层的隔水层和相对隔水层厚度在190m以上；充填未接顶高度应控制在2．0m内，采动后的安全厚度应大于65m；对空区及时、高质量充填有利于永久防水矿柱的回收；理论的采空区极限暴露面积可达3360—4000m^2．因此，在满足以上研究参数条件下，采用充填法对康家湾永久防水矿柱进行回收是完全可行的．

The ore body in Kangjiawan Mine is a typical large under -water ore body with extremely complicated mining conditions, which needs lots of permanent waterproof jambs, resulting in the overstock of ore resources. Analysis is made on the influences of the main constructions in the mine on the roof wall rock and the water containing layer, the ubiety between the roof and the interlayer or relative interlayer, the influence of the water containing layer and exploration drilling on jamb mining. The safety mining depth as well as the height of collapsed belt and the cranny guiding water are calculated. Furthermore, the ANSYS software is adopted to simulate the stability of the cover terrane and the maximum permit exposure area. The results are： the fault will not link the mine gob and the water body; the jamb roof is steady which is more than 190 m away from the interlayer or relative interlayer; the backfilling interspace should keep under 20 m, and the safety distance more than 65 m; backfilling the mine gobs timely with good quality is essential for mining the permanent waterproof jambs; and the theoretic maximum permit exposure area should be less than 3 360 -4 000 m^2. Therefore, the mining technology of the permanent waterproof jambs in Kangjiawan Mine is entirely feasible using the backfilling method with the parameters above.