以准东煤田大井二号煤矿BM煤层的分层开采为例,利用FLAC~(3D)数值模拟得到采动后上覆岩层的体积应变增量切片。分析结果表明:受煤层采动影响,覆岩移动破坏区域由采空区向深部延伸,大致呈鞍形分布。覆岩裂隙发育速度随各分层开采逐渐减缓,裂隙发育高度与已采煤层厚度成幂函数关系。 Taking the stratified mining of BM coal seam of Dakei No.2 coal mine in Zhudong coalfield as an example, the volumetric strain increment slice of overlying strata after mining is obtained by FLAC 3D numerical simulation. The result of the analysis shows that affected by coal mining, the area of ​​overlying strata movement and failure extends from the gob to the deep and is roughly saddle-shaped. The development speed of the overburden fractures gradually slowed down with the stratified mining, and the fracture development height had a power function relationship with the thickness of the coal seam.