厚松散层近浅埋煤层开采导水裂缝动态演化规律研究

Dynamic evolution of water-conducting cracks in shallow seam mining with thick alluvium

以陕北矿区韩家湾煤矿2304工作面为研究对象,通过理论分析、理论计算、相似模拟实验等方法,对厚松散层近浅埋煤层开采导水裂缝动态发育规律开展相关研究。通过建立采动岩土层动态移动变形预计模型,给出全盆地下沉、水平变形预计公式;建立了以关键层下沉为关键参数的上行导水裂缝发育高度和以隔水层移动变形为关键参数的下行导水裂缝发育深度计算方法;分析预计2304工作面推进过程中上行裂缝和下行裂缝的动态发育变化过程,相似模拟实验现象与预计结果基本吻合。研究可为相似地质条件下采动裂缝发育预计提供参考。

The 2304 working face of a mine in northern Shaanxi is taken as the research object. Through theoretical analysis, theoretical calculations, similar simulation tests and other methods, the dynamic development of water-transmitting cracks in shallow coal seam mining with thick alluvium is studied. By establishing a prediction model for the dynamic movement and deformation of the mining rock and soil layers, the basin-wide subsidence and horizontal deformation prediction formulas are given. The calculation methods are established for the development height of upward water-conducting fractures and development depth of downward water-conducting fractures, in which the critical parameter is the subsidence of the key stratum and the movement and deformation of the impermeable layer, respectively. The dynamic development of upward cracks and downward cracks during the advancement of 2304 working face is analyzed and predicted. The similar simulation experiment phenomenon is basically consistent with the predicted result. The research can provide reference for the prediction of mining fracture development under similar geological conditions.