异形煤柱条件下工作面采动冲击地压机制研究

Study on the mechanism of mining rock burst in workingface under the condition of special-shaped coal pillar

亭南煤矿4号煤经鉴定和评价均具有强冲击危险,针对回采时受超前应力、“工作面见方”大采空区连空、巷道群等因素影响,冲击风险高、治理难度大的难题,通过开展强冲击煤层、异形煤柱条件下工作面冲击地压治理技术研究,借助断裂力学、损伤力学、突变理论及时效损伤模型,建立坚硬顶板条件下上述各种煤柱动静载叠加失稳力学模型,分析采动影响下坚硬顶板破断失稳对异形煤柱动力失稳的扰动效应,分区域、分阶梯、分等级制定有针对性的治理措施,降低冲击地压发生风险和不断优化卸压方案,提高卸压效果,保证工作面安全回采。

The No.4 coal seam of Tingnan Mine has strong impact risk after identification and evaluation.In view of the problems of high impact risk and difficult treatment due to the influence of advanced stress,'square'large goaf and roadway group during mining,through the research on the treatment technology of rock burst in working face under the condition of strong impact coal seam and special-shaped coal pillar,with the help of fracture mechanics,damage mechanics,catastrophe theory and time-dependent damage model,the mechanical model of dynamic and static load superposition instability of various coal pillars under the condition of hard roof was established,and the disturbance effect of hard roof fracture instability on the dynamic instability of special-shaped coal pillar under the influence of mining was analyzed.Targeted treatment measures were formulated by region,step and grade to reduce the risk of rock burst and continuously optimize the pressure relief scheme,improved the pressure relief effect and ensured the safe mining of the working face.