1. School of Energy and Resource,Xi’an University of Science and Technology,Xi’an　 710054,China;2. Key Laboratory of Western Mines and Hazard Pre-vention,Ministry of Education,Xi’an　 710054,China;3. Shenhua Xinjiang Energy Co. ,Ltd. ,Urumchi　 830027,China

采动应力诱发的动力灾害是制约急斜特厚煤层群安全开采的难题之一。以乌鲁木齐矿区乌东煤矿动力灾害防控为目标,采用开采技术条件调查、理论分析、数值计算和现场监测等方法与手段,揭示采动应力畸变致诱动力灾害机理。研究表明:43号煤层产生的采动应力经其顶煤传导作用至层间夹持煤岩柱(sandwiched coal-rock pillar in seams,SCPS),同时受自重作用SCPS发生大变形,造成其倾向上部层位受拉伸应力而倾向下部层位受压缩应力,引发45号煤层+575水平南巷顶板应力高度集中,导致动力灾害频发。针对43号煤层工作面高于45号煤层工作面的开采布局,制定"先注水后爆破"解危措施。现场监测结果表明微震大事件频率由4.0次/min降至1.0次/min,电磁辐射峰值强度降至42.8 m V,动力灾害得到有效控制。

Dynamic hazards being induced by mining stress always threaten safe mining in extremely steep and thick coal seams. Aimed at prevention and control of dynamic hazards in Wudong Coal Mine,Urumchi mine area,we applied a comprehensive methodology including in-situ investigation,theoretical analysis,numerical calculation and field moni- toring to reveal mechanism of dynamic hazards being induced by distorted mining stress. The relevant results indicate that mining stress transfer from top of the No. 43 coal seam to sandwiched coal-rock pillar in seams ( SCPS),and SCPS deformed largely towards mine-out-area due to self-gravity,which causes tensile stress in its upper position and compressive stress in the bottom. Furthermore,high stress concentration is formed in the roof of the +575 level of No. 45 coal seam,leading to substantial dynamic hazards. With fully considering existing mining scheme,coupled fracturing that we injected water firstly and then blasted rock masses have been put forward and applied as hazard-relieving measures. By means of micro-seismic monitoring and electromagnetic radiation intensity,the frequency of micro-seismic big events decrease to one time per minute from four time per time,and the peak intensity of electromagnetic radiation reduces to about 42. 8 mV below the precautious line. Dynamic hazards relief obviously.

国家重点基础研究发展计划(973)资助项目(2014CB260404)；国家自然科学基金重点资助项目(U1361206)；国家自然科学基金资助项目(51504184)；

Lai Xingping,Yang Yiran,Chen Jianqiang,et al. Control of dynamic hazards induced by mining stress distortion in extremely steep and thick coal seams[J]. Journal of China Coal Society,2016,41(7):1610-1616.