基于ＦＬＡＣ３Ｄ数值模拟厚大矿体开采方案与采场稳定性研究

针对淮南某厚大铁矿-500 m中段采场回采,应用FLAC3D建模并进行开挖模拟.对不同开采方案中采场稳定性进行研究分析表明:采场开挖后,在采场四周角落处应力集中最大,易产生剪切破坏,在顶板中央发生位移变形最大,采场顶板容易垮塌;采场长宽为30 m×30 m时,采用两矿房或三矿房同时回采,采场保持稳定,最大应力集中系数为1.5,矿岩自身强度满足自稳要求;采场长宽为40 m×40 m,三矿房同时回采时,由于采空区暴露面积过大,集中系数达1.7,顶板受拉且充填体受压发生剪切破坏,矿岩不足以维持自稳状态.在大规模开采条件下,最终选定采场参数30 m×30 m三矿房同时回采为矿山开采方案.

roadway in the mud weakly consolidated soft rock strata

In view of the Huainan a heavy iron mine -500 m mining, FLAC3D was applied to build the modeling and simulate the excavation to analysis two kinds of mining scheme of stope stability. It shows that when the stope length to width positioning 30 m×30 m, stope keep stable with two rooms and three rooms mining at the same time, and the maximum stress concentration factor is 1.5, rock strength meet the stability requirement. When the stope length to width positioning 40 m×40 m and three stope mining, stress concentration factor is 1.7, the roof and filling body face shear failure under tension and compression because mined out exposed area is too large. In order to improve the mine production capacity, the scheme is selected that two stope structure parameter with 30 m×30 m and three stope mining as the mining project of mine excavation.