潘一东矿近距离煤层上行开采围岩裂隙演化规律模拟研究

结合潘一东矿深部煤层开采的具体工程地质条件,运用相似模拟、数值模拟相结合的方法,分析研究了深部煤层上行开采过程中,岩层破坏断裂、裂隙演化及下沉变形特征,进一步分析了岩层下沉变形曲线与岩层断裂、裂隙发育和受力状态的关系。研究表明:下煤层和上煤层开采过程中,岩层裂隙富集区主要分布在切眼向采空区内一定距离斜向上一定距离范围内和煤壁向采空区内一定距离斜向上一定距离范围内的岩层中;采空区正上方岩层经历一个裂隙产生、扩展、闭合的演变过程;下煤层开采时,煤壁处岩层断裂角小于切眼处;上煤层开采时,煤壁处岩层断裂角随两煤层工作面位置不同,经历一个先增大后减小的过程;岩层整体下沉曲线斜率不同区域与岩层裂隙发育情况及受力破坏状态是有密切联系的。

Fracture evolution characteristics of surrounding rock during ascending mining of closer coal seam in Panyidong coal mine

Based on the special engineering and geology condition of deep coal seam mining in Pa-nyidong coal mine, the characteristics of rock break, crack evolution and subsidence deformation during the ascending mining of deep coal seams were analyzed by physical and numerical simulations in this paper. In addition, the interrelationship between the deformation curve and the layer break, crack de-velopment, stress state was further analyzed. The results show that during the mining operation of lower and upper coal seams, the rich cracks areas are mainly located in the right side of coal wall and the left side of open-off cut and above thegob. Rock layers above the gob go through anevolutioncourse with the generating, expanding and closing of cracks. During the lower seam mining, the fractured angle in wall is smaller than that in open-off cut. During the upper seam mining, with the relative location dif-ference of coal faces in the two coal seam, the fractured angle in wallincreases firstly,and decreases af-terwards. Moreover, it has close relationship between the curve slope of roof subsidence in different area, the rock crack development condition, and the stress state.