“三下”开采井筒保安矿柱优化及地表变形模拟分析

Optimization on Shaft Safety Pillar and Numerical Simulation on Surface Deformation in“Three Under”Mining

为解决河北某矿山"三下"开采中保安矿柱压矿严重和地表变形的实际问题,运用FLAC3D数值模拟及辅助建模、图形处理软件,模拟了不同保安矿柱厚度下井筒围岩的应力应变及地表的位移变形程度,研究结果发现:相比应力应变及位移,以塑性区大小作为井筒失稳判定标准的敏感性更高;当采用充填法开采急倾斜中厚矿体时,井下关键工程必须布置在矿体30m以外甚至更远,且当此类中小型矿床埋深大于500m时,充填开采对地表影响较小。

In order to solve the practical problems of serious mine pressure on shaft safety pillar and surface deformation during"three under"mining in a mine of Hebei Province,FLAC3D numerical simulation,auxiliary modeling and graphic processing software were used to simulate the stress-strain of the surrounding rock of shaft and the surface displacement under different thickness of the pillars.The research results showed that compared with the stress-strain and displacement,taking the size of the plastic area as criterion of shaft instability was more sensitive.When the filling method was used to mine the deeply inclined and medium thick ore body,the critical roads and shafts should be arranged 30 maway from the ore body at least.And the filling mining would have little impact on the surface,when the buried depth of such small and medium-sized deposits was greater than 500 m.