为研究特厚煤层分层开采过程中已采工作面上覆围岩破坏高度,以老虎台矿83002已采工作面为例,分别采用EH-4物理探测、数值模拟和微震监测等多种手段进行分析论证。EH-4探测确定了垮落带和裂隙带位于油页岩层内,高阻区位于绿色页岩和砂砾岩的交界面,F1断层处出现离层空间,数值模拟和微震监测对该结果进行了验证;数值模拟和微震监测综合确定了覆岩破坏高度为400~485 m,为累计采高的6.3~7.5倍。研究成果可对下一分层83003工作面的安全开采进行指导,为类似条件矿井提供借鉴。
To research the failure height of overburden strata on mined face in slicing mining process of ultra thick coal seam,taking the 83002 mined face in Laohutai coal mine as example,the analysis and demonstration were conducted by using multiple means such as EH- 4 physical detection,numerical simulation and microseismic monitoring etc. Through EH- 4 physical detection,it was determined that the caving zone and fractured zone located in the oil shale strata,the high resistivity zone located in the interface between the green shale and gravel rock,and the separated strata space appeared in F1 fault.The numerical simulation and microseismic monitoring verified the results. By the comprehensive analysis of numerical simulation and microseismic monitoring,it was determined that the failure height of overburden strata was 400 ~ 485 m,which was 6. 3 ~ 7. 5 times of total mining height. The results can provide guidance for the safe mining of 83003 face in next slice,and provide reference for mines with similar conditions.