含瓦斯煤气固耦合扩容诱发动力灾变的力学机制

Gas dynamical disaster frequently happens under high mining-induced stress on low permeability outburst and no bump proneness coal seam in deep mining. This kind of dynamic disaster seems bursting and bursting but not. Its characteristics and mechanical characteristics are different from coal and gas outburst and rock burst, thus need to aware and study deeply. This item aims at the abnormal occurrence of gas dynamical disaster caused by high mining-induced stress choosing a new angle of the dilatancy mechanical behavior for coal containing gas. The dynamic evolvement process and mechanics response rules of dilatancy under different phases will be studied according experimental study by MTS and computed tomography scan and analyzed by using field test data. The gas desorption and adsorption law and gas corrosion effect in the process of dilatancy will be explored. Mechanical evolutionary mechanism and inner physical structure will be mastered. Mechanical condition of two kinds of instability modes of slowly and rapidly damage will be determined. Mechanics criterion of abrupt destabilization for dilatancy will be built by analyzing the mechanical condition of the dynamic mutation and energy threshold of the coal containing methane dilatancy. Depending on all above studies, the mechanical essence of coal and gas dynamic disaster for dilatancy under high stress will be revealed.The research has important theoretical values high practical application values for coal and gas dynamic disaster in deep mining.

深部开采，低突出指标、无冲击倾向性煤层在高采动应力作用下仍频发煤与瓦斯动力灾害，此类动力灾害“似突非突、似冲非冲”，其表观现象和力学特征不同于煤与瓦斯突出和冲击地压，需要从新的角度进行深入认识和研究。本项目针对深部高采动应力诱发动力灾害的异常现象，以含瓦斯煤扩容力学行为做为切入点，采用MTS试验机和微纳米CT在线扫描等实验系统进行实验研究，结合现场实测数据分析含瓦斯煤在不同载荷阶段条件下扩容的动态演化过程及力学响应规律；探索瓦斯气体在扩容过程中解析吸附规律及对煤体骨架的气蚀效应；掌握扩容启动突变的内在物理构架和力学演化机制，确定含瓦斯煤动态扩容过程中缓变和突变破坏两种失稳模式的力学条件；通过分析含瓦斯煤扩容产生动力灾变的力学条件和能量阈值，构建扩容突变失稳的力学判据，揭示高应力作用下扩容诱发煤与瓦斯动力灾害的力学本质。对深部开采煤与瓦斯动力灾害的有效防治具有重要的理论价值和指导意义。

深部开采，低突出指标、无冲击倾向性煤层在高采动应力作用下仍频发煤与瓦斯动力灾害，此类动力灾害“似突非突、似冲非冲”，其表观现象和力学特征不同于煤与瓦斯突出和冲击地压，需要从新的角度进行深入认识和研究。本项目针对深部高采动应力诱发动力灾害的异常现象，以含瓦斯煤扩容力学行为做为切入点，采用MTS试验机和微纳米CT在线扫描等实验系统进行实验研究，结合现场实测数据分析含瓦斯煤在不同载荷阶段条件下扩容的动态演化过程及力学响应规律；探索瓦斯气体在扩容过程中解析吸附规律及对煤体骨架的气蚀效应；掌握扩容启动突变的内在物理构架和力学演化机制，确定含瓦斯煤动态扩容过程中缓变和突变破坏两种失稳模式的力学条件；通过分析含瓦斯煤扩容产生动力灾变的力学条件和能量阈值，构建扩容突变失稳的力学判据，揭示高应力作用下扩容诱发煤与瓦斯动力灾害的力学本质。对深部开采煤与瓦斯动力灾害的有效防治具有重要的理论价值和指导意义。