深部开采覆岩关键层对地表沉陷的影响

通过工程实例和数值模拟实验，就深部开采覆岩关键层对地表沉陷的影响进行了研究，结果表明,对于倾斜煤层而言，开采深度的增大意味着基岩厚度的增加，从而引起深部开采覆岩关键层层数一般多于浅部开采，深部开采覆岩主关键层位置距开采煤层的距离一般大于浅部开采.正是由于受深部开采覆岩主关键层位置的改变和覆岩关键层层数增多的影响，导致了深部与浅部开采地表沉陷特征的差异.

Influence of the key strata in deep mining to mining subsidence

The influence of the key strata in deep mining to mining subsidence was studied by the engineering instance and the numerical simulation respectively.From the results of above mentioned two study methods,educes that in case of the declining coal seam the deeper the mining position is located,the more the thickness of strata above coal seam increases.Therefore,the amount of key strata above coal seam in case of deep mining are usually more than that in case of mining at shallow position,and the distance between the main key stratum and coal seam in case of deep mining is much more than that in case of the shallow one.Hereby,owing to the change of the main key stratum's position and the increasing amount of the key strata,compared with mining at shallow position,the subsidence of deep mining is different with the the subsidence of shallow mining.