铜坑矿火区下不规则矿柱群集束孔大参数整体崩落

由于历史的原因,铜坑矿细脉带采区560m水平以上形成了一个由大量不规则矿柱群支撑的大面积火区不稳定工程结构系统,存在诸多安全隐患。历次垮塌和岩层活动,不仅造成资源的损失,增加了火区的蔓延和地压灾害控制的难度,也是长期制约和困扰铜坑矿生产发展的实在因素,虽经治理,触发安全事故的要素仍然存在,1997年被广西自治区定为特大事故隐患区,彻底根治和消除安全事故隐患已势在必行。经论证分析,自2003年开始实施“局部充填、分区大爆破、块体隔离、斜面放矿,最后进行封闭覆盖”的总体治理方案,2004年3月采用集束孔阶段深孔辅以局部中深孔和小硐室的方案进行第一爆区的大爆破,总装药量150t,落矿77万t,崩落面积6500m2。在爆区范围至地表形成了连续崩落体,基本消除了地压活动敏感区的地压安全隐患,资源得以回收,并为最后消除火区创造了条件。

Mass Caving of Irregular Pillars with Bundle-holes under a Fired Area in Tongkeng Mine

In the stringer lode zone of Tongkeng Mine, a unstable working system with large-scale fire area supported by number of irregular pillars was formed above 560 m level due to mining operation over the years, which caused serious safety problems. Pillar collapse and ground activities not only caused reserve loss, fired area spread and gound-control difficulty, but also were a actual factor limiting the mine production for long time. Although these problems were brought under control, the essenttial factors initiating the safety accidents remain to exist. The mining zone was assessed as "an area with serious safety problems" by Guangxi autonomous region in 1997. Therefore, the most important thing is to solve the safety problems as soon as possible. According to the demonstration and analysis, a remedy plan of "partial filling, zonal mass blasting, separated massive blocks, ore-drawing along inclined plane and final cover" was brought forward and carried out from 2003. The mass blasting in first blasting area was carried out by use of bundle deep-holes with assistant mediate deep-hole and small charged chambers on March 28, 2004. Total charged weight is 150 t, caved ore 0.77 Mt and caving area 6 500 m2. A continuous collapse body between the blasting area and surface has been successfully formed, thus solving the safety problems in the block-stress concentrating area, recovering the resources. In addition, these provide a base for eliminating the fired area finally.