强烈动压影响下锚网支护巷道矿压显现规律研究
Research on strata behaviors law of bolting with wire mesh roadway affected by strong dynamic pressure
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摘要: 为掌握强烈动压影响条件下回采巷道的矿压显现规律,以平朔井工一矿受回采动压影响全煤巷道为研究对象,采用数值模拟、锚杆无损检测、巷道围岩变形观测等方法,分析了动压巷道围岩所处应力环境和应力分布规律,评价了工作面受采动影响巷道全长范围内锚杆受力情况,确定了巷道应力集中区域范围及影响因素,总结了强烈动压锚网支护巷道围岩变形规律。结果表明:中粗砂岩顶板稳定性较好,降低了巷道所在层位应力集中程度,巷道围岩受断层和陷落柱等地质构造影响,约30%的区域锚杆受力大于60 k N,区域内巷道矿压显现较为强烈,工作面回采动压超前影响范围为60 m,动压巷道受影响总长度可达180 m,巷道地质构造等软弱地段在采动影响范围外应适当加强支护,加快工作面推进速度。Abstract: In order to obtain the strata behaviors law of roadway affected by strong dynamic pressure,taking full coal roadway affected by mining dynamic pressure fro m Pingshuo Underground No. 1 Mine as the study subject,the numerical simulation,bolt nondestructive test,surrounding rock deformation observation and other methods W ere used to analyze the stress environment which surrounding rock involved and the stress distribution,evaluate the force of roof bolt in the entire length of roadway,determ ine the scope of stress concentration area in roadway and the impact factors,and summarize the surrounding rock deformation law. The results showed that the stability of middle and coarse sandstone roof were better which could reduce stress concentration degree of the horizon of roadway. The surrounding rock affected by faults and colla pse column and other geological tectonic,the force of regional anchor in about 30% roadway was greater than 60 k N,the roadway strata behaviors in the region was more i ntense,dynamic pressure ahead of the impact of mining face in the range of 60 m,dynamic pressure roadway affected by the total length of up to 180 m. The geological tect onic weak location of tunnel should be appropriate to strengthen support outside the mining affected areas and should speed up the advance rate of working face.