上海庙矿区8煤层回采巷道失稳控制研究与应用

Study and Application on Instability Control of Mining Gateway in No.8 Coal Seam of Shanghaimiao Mining Area

内蒙古上海庙矿区首采煤层为8煤,巷道揭露岩石条件差,顶板不同程度出现淋水,岩石遇水泥化,巷道采取普通支护方式,不能有效维护巷道稳定。为此,开展了8煤层回采巷道断面及支护方案优化研究。在对现场破坏现象实际调研的基础上,分析出原回采巷道断面及支护设计缺陷;然后采用FLAC^(3D)软件,对多种设计方案进行数值模拟计算,优化回采巷道断面及支护设计,从而得出最为合理的巷道断面形状及支护参数。为了判断优化方案支护效果,对巷道表面收敛量和顶板离层量进行了跟踪监测。监测结果表明,优化后的巷道断面及支护方案可行,参数选取合理。优化方案大大改善了巷道围岩稳定状况,保证了工作面安全掘进和顺利回采。

In Shanghaimiao Mining Area of Inner Mongolia,a first mining coal seam was No.8 coal seam,the exposed rock condition of the gateway was poor and the roof of the gateway was raining in different degree.The rock with water would be mudding.A conventional support mode was applied to the gateway and would not effectively maintain the stability of the gateway.Therefore,a optimization study was conducted on the cross section and support plan of the mining gateway in No.8 coal seam.Based on the actual investigation of the site failure phenomenon,the defects of the cross section and the support design of the previous mining gateway were analyzed.Then a FLAC^3D software was applied to the numerical simulation calculation on several design plans and to optimize the cross section and the support design of the mining gateway.Thus the most rational cross section shape and support parameters of the gateway were obtained.In order to judge the support effect of the optimized plan,a tracing monitoring was conducted on the surface convergence and the roof separation of the gateway.The monitoring result showed that after the optimization,the cross section and support plan of the gateway was feasible,the parameters were rationally selected.The optimized plan could highly improve the surrounding rock condition of the gateway and could ensure the safety driving and successful mining of the working face.