摘要
针对近距离倾斜煤层开采中,覆岩裂隙发育复杂及支架失稳风险高等问题,以任楼煤矿7_(3)53、7_(2)55和7_(2)57工作面为工程背景,采用下行式开采方式,通过相似材料模拟、三维光学摄影测量与应力监测相结合的方法,系统揭示了近距离煤层开采覆岩裂隙演化规律及支架失稳调控机理。结果表明:(1)近距离下煤层开采导水裂隙带高度较单煤层增加43.5%(39.3 m增至56.4 m),覆岩受反复拉压作用导致裂隙连通性显著增强;(2)近距离下煤层开采形成悬臂梁结构,支架初期分担顶板压力,但随着暴露面积扩大迅速达到极限载荷0.56 MPa,脆性断裂后冲击压实产生0.6 MPa峰值压力,揭示顶板-支架动态耦合失稳机制;(3)位移场分析表明,近距离下煤层开采最大位移达4.6 m,影响范围较单煤层增加了2.47 m,突水风险显著升高。研究成果提出了导水裂隙带预测模型、支架关键参数及风险调控策略,为近距离倾斜煤层安全开采提供理论支撑。
In view of the complex development of overlying rock fissures and the high risk of support instability inclose distance and inclined coal seam mining,takes the 7_(3)53,7_(2)55 and 7_(2)57 working faces of Renlou coal mine as the engineering background,and adopts the downward mining method.Through the combination of similar material simulation,three-dimensional optical photogrammetry and stress monitoring,the evolution law of overlying rock fissures and the regulation mechanism of support instability in close-distance coal seam mining are systematically revealed.The results show that:(1)The height of water flowing fractured zone in close distance lower coal seam mining is 43.5%higher than that of single coal seam(39.3 m to 56.4 m),and the fracture connectivity is significantly enhanced by repeated tension and compression of overlying rock.(2)The cantilever beam structure is formed in the mining of close distance lower coal seam.The roof pressure is shared by the support at the initial stage,but the ultimate load reaches 0.56 MPa rapidly with the expansion of the exposed area.The peak pressure of 0.6 MPa is produced by impact compaction after brittle fracture,which reveals the dynamic coupling instability mechanism of roof-support.(3)The analysis of displacement field shows that the maximum displacement of close distance lower coal seam mining is 4.6 m,the influence range is 2.47 m higher than that of single coal seam,and the risk of water inrush is significantly increased.The research results put forward the prediction model of water flowing fractured zone,the key parameters of support and the risk control strategy,which provides theoretical support for the safe mining of close distance and inclined coal seam.
作者
赵铭
许大强
欧东东
董兵
方家鑫
鞠照强
李霄
ZHAO Ming;XU Daqiang;OU Dongdong;DONG Bing;FANG Jiaxin;JU Zhaoqiang;LI Xiao(Cultivation Base of State Key Laboratory of Mine Disaster Prevention and Control,Shandong University of Science and Technology,Qingdao 266590,China;National Key Laboratory of Intelligent Construction and Health Operation and Maintenance of Deep Engineering,China University of Mining and Technology,Xuzhou 221116,China;Renlou Coal Mine,Anhui Hengyuan Coal and Electricity Co.,Ltd.,Huaibei 235000,China)
出处
《煤炭技术》
2025年第6期109-115,共7页
Coal Technology
关键词
近距离倾斜煤层
覆岩裂隙演化
支架失稳调控
导水裂隙带
周期来压
close distance and inclined coal seam
overlying rock fracture evolution
control of support instability
water flowing fracture zone
periodic pressure
