采动应力路径下深部煤体扰动特征

为研究采动条件下工作面前方煤体应力变化规律与扰动破坏特征，以平煤十二矿己15-31030工作面为研究对象，通过现场原位实验与三维数值模拟研究，给出了不同应力状态下的扰动强度判别指标，以煤体主应力为中间量，将采动应力与工作面前方煤体破坏特征联系起来，得到了采动应力演化规律及采动应力路径下煤体变形特征。原位单轴实验表明工作面前方煤体采动应力不是单纯的增加，而是经历了原岩应力、缓慢上升、急剧升高、突然卸荷4个状态，而三维数值实验得出侧压力系数大小与扰动状态具有一定的相关性。根据已有的应力路径，数值再现了单向、三向采动应力状态下煤样的变形规律和塑性分布状态。

Disturbance characteristics of deep coal mass under the mining stress path

In order to derive the stress variation and failure characteristics of coal mass in front of working face under mining disturbance conditions,the discriminant index of the disturbance strength under different stress states is proposed through in situ experiments and three dimensional numerical simulation based on the geological condition of JI15 31030 working face of Coal Mine No.12,Pingdingshan area,China.The stress evolution and the deformation characteristics of coal under mining stress path are obtained by taking the principal stress of coal mass as the intermediate quantity,which makes a connection between the mining stress and failure characteristic in front of the working face.It can be shown from in situ axial experiment that the mining stress of the coal in front of the working face is not a simple increase,but presents four states for the original rock stress,slow increase,sharp rise and sudden unloading.The 3D simulation results show there is a certain correlation between the side pressure coefficient and the disturbance state.According to the derived stress paths,the deformation law and plastic distribution state of coal samples under axial and triaxial mining stress state are reconstructed.