葫芦素煤矿上覆岩体运移规律及“上三带”发育高度

Movement pattern of overburden rock mass at Hulusu Coal Mine and the“upper three zones”heights

为研究大采宽条件上覆岩体运移与离层空间发育规律及“上三带”的关系,以内蒙葫芦素煤矿21406工作面与21101工作面为研究对象。采用多种方法如理论预测、建立模型进行数值模拟、钻探取芯观测岩性与裂隙发育、注水测量漏失量与窥视等方法研究了回采面开采后上覆岩层移动与变形规律与“上三带”发育关系。21406工作面位移呈“中间大、两边小”的分布态势,其运动速度先增加后减小,并在推过钻孔138 m处取得极大值;工作面推过138~178 m的范围内,为离层演化和发育的核心区间,并在322 m开始减弱并发生闭合;离层空间分布在距离煤层约260 m向上区域。21101工作面随着推进距离的增加,裂隙发育范围由“拱形”逐步演化为“马鞍形”,其发育的高度在推进80 m时达到61.6 m的最大值;注水实测导水裂隙带高度为65.39 m,裂采比为22.54倍。离层空间含水层发育在煤层上方260 m以上,远离导水裂隙带范围。本文研究结果为离层注浆与顶板疏放水提供了较为扎实的设计依据。

The movement pattern of overburden rock mass and the distribution of the“upper three zones”under fully mechanized mining conditions are studied from the 21406 and 21101 working faces of Hulusu Coal Mine through theoretical calculations,numerical simulations,drilling,water injection,and borehole camera technology methods.The results show that the movement of the 21406 working face presents a distribution pattern of“large in the middle,small on both sides”,with its movement speed initially increasing and then decreasing,reaching a maximum value after 138 m of the borehole,within the range of 138-174 m,it is the core interval for the development and evolution of separation layer space,which begins to weaken and close at 322 m.The separation space is distributed in the area about 180 m above the coal seam.The water-conducting fracture zone of the 21101 working face gradually evolves from an“arch shape”to a“saddle-shape”as the distance advanced,reaching a maximum height of 61.6 m at 60 m advance of working face.The water injection test measured the height of the water-conducting fracture zone at 65.39 m,The splitting and mining ratio is 22.54 times.The aquifer in the separated space is developed above the coal seam at a depth of 260 m,indicating that the fracture zone is distant from the aquifer in the separation layer space.These research results provide a solid foundation for separate layer grouting and roof water drainage.