跨采底板大巷围岩应力演化特征及压裂卸压控制研究  

Study on stress evolution characteristics and fracturing pressure relief control of surrounding rock in cross-mining floor roadway

作　　者：刘怀东 刘长友[1] 刘江伟 LIU Huaidong;LIU Changyou;LIU Jiangwei(State Key Laboratory of Coal Resources and Safe Mining,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China;School of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao,Shandong 266590,China)

机构地区：[1]中国矿业大学煤炭资源与安全开采国家重点实验室,江苏徐州221116 [2]山东科技大学能源与矿业工程学院,山东青岛266590

出　　处：《采矿与安全工程学报》2023年第3期488-497,共10页Journal of Mining & Safety Engineering

基　　金：国家自然科学基金项目(52074267)。

摘　　要：针对跨采底板巷道变形大、难以维护难题,以祁南煤矿跨采东翼底板轨道运输大巷为工程背景,采用FLAC^(3D)数值模拟与现场实测相结合的方法,研究工作面跨采过程中底板巷道围岩应力场分布及煤层底板岩层破坏特征,确定合理的压裂层位与时机,分析不同压裂参数下巷道围岩应力转移规律,提出压裂卸压控制技术方案。研究结果表明:随着底板巷道与回采工作面水平距离的减小,巷道围岩应力集中程度与高应力区范围明显增大,导致巷道围岩变形加剧;压裂工作应在煤壁前方底板高应力区与巷道围岩高应力区贯通前完成;巷道上方粉砂岩作为主要承载和施载层,是压裂的关键层位;压裂卸压后,煤壁前方高应力区由巷道向压裂区转移,随着压裂区宽度增大,巷道两帮垂直应力峰值逐渐降低并趋于稳定;合理的压裂区范围为巷道左侧宽14 m、右侧宽10 m。现场工业性试验表明,岩层压裂卸压对跨采底板巷道围岩稳定性控制效果显著。In order to solve the problem of large deformation and difficult maintenance of cross-mining floor roadway,this paper takes the track transportation roadway across the east floor of Qinan Coal Mine as the engineering background,studies the surrounding rock stress field distribution of floor roadway and the failure characteristics of coal seam floor in the process of cross-mining with the method of FLAC^(3D)numerical simulation and field measurement.The reasonable fracturing layer and timing are determined,the stress transfer law of roadway surrounding rock under different fracturing parameters is analyzed,and the fracturing pressure relief control scheme is put forward.The results show that with the decrease of the horizontal distance between the floor roadway and the mining face,the stress concentration degree of the surrounding rock of the roadway and the range of the high-stress area obviously increase,which leads to the aggravation of the deformation of the surrounding rock of the roadway.Fracturing should be completed before the high-stress area of the floor in front of the coal wall and the high-stress area of the surrounding rock of the roadway,and the siltstone above the roadway as the main bearing and loading layer is the key layer of fracturing.After fracturing pressure relief,the high-stress zone in front of the coal wall transfers from the roadway to the fracturing zone.With the increase of the width of the fracturing zone,the peak vertical stress of the two sides of the roadway gradually decreases and tends to be stable.The reasonable range of the fracturing zone is 14 m on the left side and 10 m on the right side of the roadway.The field industrial test shows that rock fracturing and pressure relief have a remarkable effect on controlling the surrounding rock stability of the roadway across the mining floor.

关 键 词：采动应力 底板大巷 水力压裂 应力转移 

分 类 号：TD353[矿业工程—矿井建设]