进路宽度对松散尾砂充填体下护顶层的稳定性影响研究

Study on the Influence of Width of Entrance on Stability of Top Protection Layer under Loose Tailings Backfill

为探明进路宽度对松散尾砂充填体下护顶层的稳定性影响,以某矿采空区隔离矿柱回采为背景,设计了不同进路宽度下顶部隔离矿柱的回采方案,并利用FLAC^(3D)软件对回采过程进行模拟,分析了2种进路方案下矿柱回采时护顶层塑性区的演化规律。研究结果表明:不同进路宽度下上覆充填体塑性区破坏规律基本一致,塑性区集中在护顶层中部,边缘破坏较小;当进路宽度为3 m时,护顶层暴露面积小,塑性区范围相对较小;基于力学分析,进路宽度为3 m时可以降低护顶层的留设厚度,提高矿石回收率。本研究可为类似地下矿山采空区隔离矿柱的回采提供参考。

In order to explore the influence of width of entrance on the stability of the top protection layer under the loose tailings filling body,taking the isolation pillar mining in a mine goaf as the back-ground,the mining scheme of the top isolation pillar under different drift widths was designed,and the min-ing process was simulated by FLAC^(3D) software.The evolution law of the plastic zone of the top protection lay-er during pillar mining under two schemes is analyzed.The results show that the failure law of the plastic zone of the overlying filling body under different width of entrance is basically the same.The plastic zone is concentrated in the middle of the top protection layer,and the edge damage is small.When width of en-trance is 3 m,the exposed area of the top protection layer is small,and the plastic zone is relatively small.Based on the mechanical analysis,when the width of entrance is 3 m,the thickness of the top protection lay-er can be reduced and the ore recovery rate can be improved.This study can provide reference for the recov-ery of isolated pillars in goaf of similar underground mines.