采动覆岩裂隙动态演化规律的三维模拟

Three-dimensional Simulation of Dynamic Evolution of Mining-induced Overburden Fractures

以新景矿3213工作面为背景,基于非连续介质的离散元方法,对工作面回采过程中覆岩运移和裂隙演化规律进行了三维全过程数值模拟。研究结果表明:覆岩的裂隙富集区形态、大小范围会随着工作面的推进发生变化;在工作面推进初期呈'拱形'形态,当推进到80 m时,由于采空区中部裂隙逐渐压实而呈'中部镂空的圆拱型'形态,开采完成后则成'圆环状'形态;且在此'圆环'中不同位置的裂隙富集区大小也存在一定差异,在采空区倾向两端的裂隙富集区形态近似相同,而沿工作面走向,工作面上方裂隙富集区的宽度和高度略大于开切眼处。

Based on the discrete element method of discontinuous media,the whole process analysis of overlying stratum migration and fracture evolution in coal mining process of 3213 face of Xinjing Mine is carried out by using 3D numerical simulation software.The results show that the shape and size of fractured enrichment area of overburden rock will change with the advancing of working face.At the initial stage of working face advancing,it takes on the shape of'arch'.When working face advances to80 m,it takes on the shape of'hollow circular arch'due to the gradual compaction of the central fissure in the goaf,and becomes'circular ring'after the mining is completed,and there are some differences in the size of the fracture enrichment zones at different positions in the'circle'.The morphology of the fracture enrichment area at both ends of the goaf tendency is approximately the same,and along the mining direction,the width and height of the fissure enrichment area above the working face is slightly larger than the open-off cut.