论文部分内容阅读
实验和野外观测表明颗粒破碎显著影响高孔隙岩石的变形特征.为建立高孔隙岩石变形的数值模型,我们以弹性理论为基础并根据问题的特征进行合理简化,给出了一种颗粒破碎机制,并根据此颗粒破碎条件改进传统的离散单元模型.利用改进的离散单元模型,研究了不同压力条件下高孔隙岩石变形的宏观和微观特征.数值模拟结果表明考虑颗粒破碎的模型能重现高孔隙岩石在不同围压下变形的应力-应变关系、声发射特征、应变局部化和剪切增强压缩等特征.我们还发现,与野外观测结果一致,在高孔隙岩石脆性阶段剪切带内部及附近伴有显著的颗粒破碎.
Experiments and field observations show that the particle breakage significantly affects the deformation characteristics of high-porosity rocks.In order to establish a numerical model of high-porosity rock deformation, based on the elastic theory and based on the characteristics of the problem, a simplified particle crushing mechanism is proposed, And the traditional discrete element model is improved according to the particle crushing conditions. The macroscopic and microscopic characteristics of high pore rock deformation under different pressure conditions are studied by using the improved discrete element model. The numerical simulation results show that the model considering the particle crushing can reproduce the high porosity The stress-strain relationship, acoustic emission characteristics, strain localization and shear enhancement compressions of rock under different confining pressure also found that, consistent with the field observations, in the vicinity of the shear band in the high-porosity rock fragile stage Accompanied by significant particle breakage.