采动应力分布特征的深度效应
Depth Effect of Mining Stress Distribution Characteristics
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摘要: 为研究神东矿区采煤深度增加引起的采动应力分布变化特征,采用FLAC3D数值模拟软件,构建数值试验模型,分析不同采深模型下应力拱形态、超前应力峰值、位置及影响范围变化特点。通过研究不同开采深度采动应力分布特征的变化规律,得出了采深效应的作用机制。研究表明:通过分析数值模拟结果,发现不同埋深条件下工作面超前支承压力峰值距煤壁距离约8~12 m,受工作面开采剧烈影响范围(应力集中区域)约87~99 m,两者都随着埋深的增加而增大。上覆岩层形成的应力拱结构是影响采动应力分布特征的根本原因。针对深部矿井巷道围岩变形严重问题,提出了水力压裂措施,通过现场验证取得了良好的效果。Abstract: To study the change characteristics of mining stress distribution caused by the increase of mining depth in Shendong Mining Area, FLAC3D numerical simulation software was used to build a numerical test model to analyze the variation characteristics of stress arch morphology, advancing stress peak, position and influence range under different mining depth models, and explore the variation rules of mining induced stress distribution characteristics with the increase of mining depth. The mechanism of the depth effect was analyzed by studying variation of mining stress distribution characteristics at different mining depths. The research shows that: peak leading abutment pressure of the working face is about 8-12 m away from the coal wall under different buried depths. The range affected by mining of the working face(stress concentration area) is about 87-99 m. Both increase with burial depth. It is found that the stress arch structure formed by the overlying strata is the root cause of the characteristics of the mining stress distribution. In view of the serious problem of surrounding rock deformation of mine roadway, hydraulic fracturing measures were proposed.