不同采煤方法下开采沉陷控制的数值模拟研究

为了对比充填开采及条带开采对地表及覆岩破坏控制的效果，本文基于实验室制备的充填材料和理论计算得到的条带开采方案，运用数值模拟软件FLAC3D对垮落开采、条带开采、充填开采过程中地表移动变形及覆岩应力场变化情况进行详细分析。结果表明：充填开采中覆岩释放了少许弹性应变能，其应力略小于原岩应力，覆岩应力场呈线性规律变化。条带开采中覆岩应力场出现应力增高区，煤柱两端应力集中现象严重，围岩稳定性弱于充填开采。两种开采方法下地表沉陷均远小于垮落开采，条带开采中地表各变形值均小于建筑物I级破坏允许值，充填法中地表曲率仅比该允许值大0.02m-1·10-3，仍能保证地面建筑物的安全性。故采用充填开采对地表及覆岩变形的控制效果更佳。

The numerical simulation of the control of mining subsidence in different mining methods

The surface deformation and the variation of overburden stress field in different mining methods are analyzed by FLAC3D in order to contrast the control?effect of surface and overlying?strata deformation between filling mining and strip mining,which are based on the filling material prepared in the lab and the theoretical strip mining scheme. The results show that a little of overburden elastic strain energy is released in the filling mining, which stress is smaller than the in-situ rock?stress and the stress field varies with?an almost?linear?fashion.There exist high-stress area in the overlying?strata and stress concentration in the coal pillar of strip mining,so the stability of surrounding rock is less than the filling mining.The surface subsidence in the two mining methods is far less than the caving mining and the values of surface deformation are less than the allowable values of the buildings grade I in strip mining.Though the value of surface curvature is 0.02 m- 1·10-3 bigger than the allowable value in filling mining, it can insure the safety of ground buildings.So,the control?effects of surface and overburden deformation are the best in the filling mining.