峰丛地貌浅埋煤层开采诱发陡倾层状山体失稳机理研究

Under peak grouped relief, geological hazards can be easily induced by shallow seam mining under steep mountains such as landslide and rock-avalanche, which will seriously limit coal safety mining and mountain environment protection in Southwest Region. Centering on “steep mountain under peak grouped relief” and “shallow seam mining”, physical simulation, numerical simulation and theoretical analysis will be adopted to reveal the stability and the intrinsic steep mountain failure mechanism induced by shallow seam mining. Firstly, the tridimensional geomechanical model of the steep inclined mountain will be reconstructed. The inversion of mountain failure process induced by mining is carried out. Then, the space-time evolution regularities of stress, displacement and fracture field in steep mountain can be deeply studied before and after mining. The crack inoculation, propagation and transfixion mechanism will be revealed. Calculation method of the steep mountain safety factor will be constructed by theoretical analysis. As a result, the relationship between the safety factor with engineering specification and mining technical indexes can be obtained. Lastly, criterion of steep mountain failure mode induced by mining will be established as well. The final research results will provide theoretical support for shallow seam mining and mountain protection, which has a great theoretical significance and engineering application value.

峰丛地貌陡倾层状山体下浅埋煤层开采易诱发山体滑坡、崩塌等地质灾害，制约了西南地区煤炭资源安全开采及山地环境保护。本项目紧紧围绕“峰丛地貌陡倾层状山体”、“浅埋煤层采动”两个关键因素，采用物理模拟、数值模拟、理论分析对峰丛地貌陡倾层状山体稳定性及采动诱发山体失稳机理进行深入研究。通过重构陡倾层状山体三维地质力学模型，反演浅埋煤层采动诱发陡倾层状山体失稳历程，研究采动作用前后陡倾山体应力场、位移场、裂隙场时空演化特征，揭示采动作用下陡倾山体裂隙面“孕育-扩展-贯通”机制；通过建立采动作用下陡倾层状山体安全系数计算方法，融合分析浅埋煤层工程地质条件及开采技术指标对安全系数的影响，建立浅埋煤层采动诱发陡倾层状山体失稳判据。研究结果将为西南峰丛地貌下浅埋煤层安全开采及矿区山体保护提供理论支撑，具有重要的理论意义和工程应用价值。

为了摸清峰丛地貌浅埋煤层采动作用下诱发陡倾层状山体失稳机制，本项目采用物理实验、数值模拟、理论分析及现场实测等方法，紧紧围绕“浅埋煤层采动作用”、“陡倾层状山体稳定性”两个关键因素，对峰丛地貌陡倾层状山体稳定性及采动作用诱发山体失稳机理开展深入研究，分析了峰丛地貌陡倾层状山体稳定性，研究了浅埋煤层采动诱发陡倾层状山体失稳机理，建立了陡倾层状山体稳定性与浅埋煤层采动作用间的内在联系，为贵州矿区山体保护、煤炭安全开采提供理论支撑。主要研究内容如下：.1）通过对贵州煤矿地表坡体危岩受采动影响前后的稳定性系数进行计算研究，分析地下采动对地表坡体稳定性的影响以及由于采动效应对采空区上覆岩层裂隙的发育情况，总结归纳出地下采动对坡体稳定性的影响因素以及坡体危岩的分布范围和规模形态，得出坡体危岩的基本力学特征；分析了坡体在未受地下采动影响的原始状态稳定性，提出危岩的破坏模式以及形成机理和影响因素。.2）研究煤层开采对上覆岩层的裂隙情况以及坡体在采动情况下的应力及位移的变化情况；研究煤层采高以及煤层倾角对坡体稳定性的影响；分析了工作面留设局部煤柱后采空区上覆岩层裂隙发育情况以及坡体应力、应变及位移变化情况，分别从地下控制以及地表治理两个方面提出坡体稳定性的控制及治理建议。.3）运用理论分析、数值模拟、物理模拟等研究方法，针对普洒煤矿山体地貌下浅埋煤层开采过程中基本顶岩层的移动规律及煤层开采引起的地表沉陷形式等内容进行了深入研究；对峰丛地貌下浅埋煤层工作面开采覆岩运动及裂隙演化进行研究。