露天台阶下空区安全隔离层计算及稳定性分析

我国很多露天矿山存在开采境界下有空区危害的现象，安全隔离层厚度及稳定性分析是保证露天安全开采的关键，也是迫切需要解决的问题。以广东省大宝山露天矿开采为例，理论计算得出不同跨度下的安全隔离层厚度，再结合数值模拟软件建立二维空区模型进行模拟，比较理论计算和数值计算的结果。通过二者的比较最终得出不同跨度下最佳的安全隔离层厚度。最后就矿山具体存在的空区群，建立三维空区群模型进行稳定性分析。为露天开采境界下空区稳定性分析提供了一套系统的方法。

Safety Isolation Layer Calculation and Stability Analysis of Cavity under Open Pit Bench

There are many open pits in China threatened by cavities under open pit limit.The key to insure safe mining depends on the thickness of safety isolation layer between cavity and bench surface，and it needs to be solved urgently with the steps of bench blasting.Based on the present situation of Dabaoshan mine which is an open pit with lots of harmful cavities under open pit limit，the thickness of safety isolation layer under was calculated by using different theoretical methods，and the results simulated by 2D numerical method were compared with those theoretically calculated ones.The optimum thickness of safety isolation layer under different cavity span was obtained through comparison.Finally，an actual cavity group with three cavities under open-pit limit was modeled in 3D to calculate its stability.These provide a systematic stability analyzing method of cavity under open pit limit for the mine.