北京房山大安山煤矿深部地应力数值模拟分析

The concentration region numerical simulation analysis and prediction research in Daanshan coal mine deep stress

地应力是煤矿开采等地下工程围岩变形与破坏的根本驱动力。为研究随煤矿开采深度的增加,地应力越来越大,井下应力环境发生变化,导致巷道大变形、冲击矿压、煤与瓦斯突出及突水等灾害的发生,与工程实测对比分析对某煤矿+400m水平的断层、褶皱地质构造应力场进行数值模拟研究,再现地应力的大小对开采活动的影响情况,充分了解应力场分布特征、煤岩体性质与结构特征,进行合理的、切合实际的围岩稳定性、围岩变形与破坏分析,为合理的支护设计与冲击地压的防治提供依据。模拟显示:(1)应力值大小分布的总体趋势是随深度的增加而逐渐增大,但在同一水平上应力值相差不大;(2)剪应力对断层的影响明显,剪应力值明显高于其余部分;(3)最大主应力大小分布的总体趋势是随深度的增加而逐渐增大,在煤层倾角变化比较大的区域出现应力升高区和应力降低区。与工程实际有很好的吻合。

Stress is the fundamental driving force of deformation and failure of surrounding rock in coal mining and other underground engineering. To resolve the problem that the downhole environment has changed with the coal mining depth increasing and the situ stress growing which would cause the large deformation of roadway,rock burst coal and gas outburst,water inrush and other disasters,this paper adopts the comparative analysis method to simulate the stress field of the horizontal fault in + 400m level and folds geological structure which could reproduce the effects of the in-situ stress on the exploitation activities,the full understanding of the stress field distribution and properties and structure characteristics of coal-rock mass can help us to make reasonable and practical analysis for the stability or deformation and failure of surrounding rock to provide basis for the supporting design and the prevention and treatment of rock burst. The simulation shows that:( 1) The overall trend is that the stress distribution increased gradually with the increase of depth,but at the same level,the stress were not significant;( 2) The influence of shear stress on fault was obvious and it was significantly higher than the rest;( 3) The overall trend of the maximum principal stress distribution is that it increased with depth increases,In the place that coal seam angle changed big appeared the stress decreasing and increasing zones and which has a very good match with the engineering practice.