饱和状态下硬岩三轴流变变形与破裂机制研究

Studies on triaxial rheological deformation and failure mechanism of hard rock in saturated state

利用岩石全自动流变伺服仪对饱和状态下坚硬大理岩和绿片岩进行了三轴压缩流变试验,基于得到的硬岩三轴流变试验结果,研究了硬岩在不同围压作用下的轴向应变以及侧向应变随时间的变化规律,从而为岩石工程流变数值分析时参数的辨识提供了可靠的试验依据。然后研究了硬岩轴向变形与侧向变形之间的关系,探讨了围压与粒径对岩石轴向以及侧向变形特性的影响规律,分析了岩石三轴流变过程中的塑性变形特性,讨论了流变应力水平对岩石侧向-轴向变形特性的影响规律。最后对不同围压作用下岩石流变破裂断口微细观特征进行了分析。

Triaxial compression rheology experiments of hard marble and greenschist specimens in saturated state were carded out on the rock servo-controlling rheology testing machine. Based on the triaxial rheological experimental results of hard rock, the variance of axial and lateral strains of hard rock with the time under different confining pressures was investigated, and it provided important reference for the identification of parameters in the rheological numerical finite element analysis of rock engineering. Then the relation between axial deformation and lateral deformation of rock was investigated. The effect of confining pressure and grain size on the axial and lateral deformation properties was analyzed. At the same time, the plastic deformation property of rock in the process of triaxial rheology was also analyzed. The effect of rheological stress level on the lateral-axial deformation property of hard rock was discussed detaiUy. In the end, microscopic characteristics of rheological failure shaping fracture of rock under different confining pressures were analyzed.