大结构无底柱分段崩落法覆盖层厚度研究

Study on overburden thickness of large structure sublevel caving method without sill pillar

为了确定30m×20m大结构参数无底柱分段崩落法合理的覆盖层厚度,通过理论计算和数值模拟方法对覆盖层厚度进行了研究。先根据放矿椭球体理论、缓冲冲击气浪计算出覆盖层厚度分别为43.8m、22.5m;然后利用PFC^3D对不同覆盖层厚度下放矿进行了模拟,得出矿石回收率、废石混入率指标最优时的覆盖层厚度为45m。综合理论计算和数值模拟结果,推荐矿山合理的覆盖层厚度为45m,可确保生产安全并取得较好技术经济指标。

In order to determine the reasonable overburden thickness of the 30 m×20 m large structure parameter’s sublevel caving method,the thickness of the overburden was studied by theoretical calculation and numerical simulation.Firstly,according to the ore ellipsoid theory and buffered the shockwave,the thickness of the overburden was calculated to be 43.8 m and 22.5 m respectively.Then,the PFC^3D was used to simulate the ore drawing with different overburden thickness,it was concluded that when the thickness of the overburden was 45 m,the ore recovery rate and the waste in-ore rate were the best.Based on the comprehensive theoretical calculation and numerical simulation results,it was recommended that the reasonable overburden thickness of the mine was 45 m,which can ensure production safety and achieve better technical and economic indexes.