水力压裂卸压技术在双U工作面留巷围岩控制中的应用  

Application of hydraulic fracturing pressure relief technology in surrounding rock control of double-U roadway retaining

作　　者：吴建星[1,2,3] WU Jianxing(Mining&Designing Department,Tumdi Sciences&Technology,Co.,Ltd.,Beijing 100013,China;Mining&Designing Department,China Coal Research Institute,Beijing 100013,China;School of Energy and Mining,China University of Mining and Technology(Beijing),Beijing 100083,China)

机构地区：[1]天地科技股份有限公司开采设计事业部,北京100013 [2]煤炭科学研究总院开采设计研究分院,北京100013 [3]中国矿业大学(北京)能源学院,北京100083

出　　处：《煤矿安全》2021年第5期112-119,共8页Safety in Coal Mines

基　　金：中国煤炭科工集团有限公司创新创业资金专项资助项目(2018MS021);国家自然科学基金青年科学基金资助项目(51704160)。

摘　　要：针对双U布置工作面外侧留巷巷道受到多次扰动影响,以山西潞安漳村煤矿2502工作面为工程背景,设计并实施了单排压裂孔不同压裂间距的定向水力压裂技术现场试验,探究了钻孔密度对压裂效果的影响,每个钻孔设定4个合理的压裂段,从孔底向孔口后退式分段逐次进行压裂,有效解决了顶板坚硬岩层悬而难跨问题。试验得出:定向水力压裂能够在顶板岩层中形成裂隙,破坏局部顶板的完整性,有效弱化顶板局部围岩强度,降低了应力集中程度,并减小了端头支架的工作阻力;钻孔密度对巷道围岩浅部卸压效果的影响不明显,对巷道围岩深部卸压效果明显;压裂孔布置得越密,卸压效果越好,钻孔密度提高3倍后,巷道卸压效果提升53%。综合对比分析得出:一定条件下14 m压裂孔间距经济合理;实施定向水力压裂后巷道顶底板和两帮位移量分别降低了45%和26%,对控制巷道变形效果良好。Due to the influence of many disturbances in the process of retaining the roadway outside the double U layout working face,taking 2502 working face of Zhangcun Coal Mine of Lu’an Group as the engineering background,the field tests of directional hydraulic fracturing technology for single row of fracturing boreholes with different spacings were designed and carried out,and the influence of drilling spacing on fracturing effect was explored.In the tests,four reasonable fracturing sections were set for each borehole,and the fracturing was carried out step by step from the bottom to the opening of the borehole,which effectively solved the problem of hard roof rock hanging and difficult to span.The results of field tests proved that directional hydraulic fracturing forms cracks in roadway roof rock,which weakens the strength of local surrounding rock,abates the stress concentration of roadway roof and reduces working resistance of the end bracket effectively.The density of borehole has a small influence on the unloading effect of shallow surrounding rock,but it has a big impact on deep surrounding rock.The pressure relief effect of roadway is increased by 53%after drilling density increased by 3 times,and comprehensive comparative analysis shows that the drilling spacing of 14 m is the most economical and reasonable under certain conditions.After directional hydraulic fracturing,the displacement of roadway roof and floor and two sides is decreased by 45%and 26%respectively,which has good effect on controlling roadway deformation.

关 键 词：定向水力压裂 切顶卸压 双U工作面 外侧巷道留巷 围岩控制 

分 类 号：TD322.1[矿业工程—矿井建设]