金川二矿区14行风井再加固方案的可行性研究

金川二矿区14行风井破坏返修后,新井筒上部又出现了两条较大的近水平的裂缝,对此,进一步提出对返修后井筒的再加固方案。本文结合金川矿山地表岩移GPS监测结果,采用数值模拟的方法,对再加固方案的可行性进行了论证。结果表明,实施浅部的加固措施并没有改变竖井受采动影响的程度,更未实现预期的加固效果。继而对加固锚索施加预应力来检验加固方案本身的适应性,发现加固前后竖井井壁位移和应力的大小、分布也没有明显变化。可见,对于采动影响区内的竖井,采取单纯浅部加固的方案并无效果。最后,综合考虑14行风井破坏的原因、前期加固方案存在的问题和岩移趋势,提出了进一步加固措施的建议。

FEASIBILITY RESEARCH OF FURTHER REINFORCEMENT PROGRAM FOR NO.14 SHAFT IN JINCHUAN NO.2 MINE AREA

After the No.14 shaft was repaired in Jinchuan No.2 mine,two big cracks were formed in the new shaft well. Therefore,further reinforcement program was put forward on the repaired shaft. Based on GPS monitoring data of ground surface movement, this paper evaluated the feasibility of the reinforcement program of No.14 shaft by numerical simulation. The results show that the shallow reinforcement measure did not change the extent of mining impact on the shaft,and the reinforcement method did not achieve the desired effect. Then,the prestressed cable reinforcement was used for inspecting the adaptability of this strengthening program. It was further found the level and distribution of shaft wall displacement and stress did not change significantly before and after the reinforcement. This shows that only shallow reinforcement program was not effective for the shaft which located in the severely affected region of rock movement induced by underground mining. It was a useful guide for engineering design and had practical significance in mining production. Finally,further reinforcement program was suggested after considering damage reasons of No.14 shaft,problems in the former inforcement program,as well as trends of rock movement．