钱家营矿近距离煤层巷道破坏原因及支护对策

Failure Causes and Support Countermeasures of Gateway in Seam with Close Distance to Other Seams in Qianjiaying Mine

为了安全高效地开采钱家营矿深部近距离煤层,研究了近距离煤层回采巷道的变形破坏机理并提出相应的支护对策,通过现场调查和非连续变形分析(DDA)对钱家营矿近距离煤层运输巷的变形破坏机理进行了研究。结果表明:多次动压影响是造成近距离煤层回采巷道变形破坏的根本原因;而巷道两帮移近量大于顶底板移近量主要是由于矿区水平应力远大于垂直应力所造成的。通过DDA对原支护方案进行了优化分析,提出实施3根顶锚索支护方案,中间锚索是控制顶板位移,两边锚索是将上覆岩层应力引入到深部,底角锚杆控制底鼓。现场应用表明新支护方案能有效控制运输巷顶底板及两帮移近量;证实DDA方法将可为锚杆支护巷道的优化设计提供参考。

In order to safety and high efficiently mine deep seam with close distances to other seams, the paper studied the deformation and failure mechanism of the mining gateway in seam with close distance to other seams and provided the related support countermeasures. With the site investigation and the non - continued deformation analysis, a study on the deformation and failure mechanism of the transportation gateway in the seam with close distance to other seams in Qianjiaying Mine was conducted. The results showed that the multi mining pressures influences would be the fundamental cause to cause the deformation and failure of the mining gateway in the seam with close distance to other seams and the convergence of the two side walls of the gateway higher than the floor convergence would be mainly due to the horizontal stress in the mining area highly than the vertical stress. With the DDA to optimize and analyze the previous support plan, the paper provided the three anchors support system to be implemented. The central anchor would control the roof displacement and the two end anchors would adjust the overburden strata stress to the deep of the strata. And the floor bolts would control the floor heave. The site implements showed that the new support plan could effectively control the roof and floor of the transportation gateway and the two side wall convergence. The DDA method was conformed to provide the references to the optimized design of the bolt supported gateway.