近距离下煤层过遗留煤柱应力集中区研究

Research on Left over Pillar Stress Concentration Zone in Close Distance Lower Coal Seam Mining

在我国,近距离煤层赋存和开采所占比重很大,吕梁矿区木瓜煤矿层间距小于10 m的可采储量占总储量的80%,上煤层已采完,回采工作面间遗留20 m区段煤柱,对下部煤层回采造成一定影响,所以,研究近距离下煤层过遗留煤柱应力集中区具有重要的现实意义。针对木瓜煤矿近距离上煤层采空区、遗留煤柱下巷道维护和矿压显现严重的技术难题,基于近距离煤层上部煤层开采遗留煤柱应力集中会在底板中传递的规律,对下煤层应力影响范围进行了理论计算;并结合10-103工作面的生产技术条件,采用现场矿压监测方法,对工作面上部、中部、下部位置的液压支架监测数据进行分析,采取工作面调斜和加强超前支护措施,对近距离下部煤层过遗留煤柱应力集中区具有一定的指导意义。

It has large proportion of the closed distance coal seam occurrence and mining in China, and recoverable mining coal reserves accounted for 80% of total reserves is less than 10 m layer spacing in Mugua coal mine of Lvliang mining area. The upper coal seam has mined out, coal mining face left over 20 m pillar, which influences the lower coal seam mining. So the study of under closed distance lower coal seam crossing left over pillar stress concen- tration zone is the important practical significance. According to the technical issues of roadway maintenance and mine pressure appearing serious under closed distance upper coal goal and left over pillar in Mugua coal mine, based on the closed distance upper coal mining left over pillar stress concentration will be transmitted at the floor, the influence range of lower coal seam stress is theoretically calculated. And combined with the production technology conditions in 10- 103 face,the methods of mine pressure monitoring is applied, the hydraulic support monitoring data in upper, middle and lower position of the face is analyzed, slope adjustment of working face and strengthening advanced supporting measures were taken, the results had certain guidance significance for close distance lower coal seam crossing left over pillar stress concentration zone.