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运用离散元软件PFC2D对含有圆孔裂隙组合缺陷的砂岩进行单轴压缩数值模拟,分析不同裂隙倾角时砂岩的强度特征、破坏特征以及裂纹扩展过程。结果表明:岩石试样破坏经历了裂隙的压密、微裂纹的萌生和扩展及最终的破坏几个阶段;当应力增大到一定程度之后,颗粒之间黏结断裂,微裂纹不断产生、汇集和贯通,最终形成宏观裂纹,使得试样发生失稳破坏。与完整砂岩试样相比,含圆孔裂隙砂岩试样的力学参数均显著降低,且降低幅度与裂隙倾角相关;随着裂隙倾角的不断增大,试样的峰值强度表现为不断增加的特征。
Discrete elemental software PFC2D is used to simulate the sandstone with round hole fracture combination defects under uniaxial compression. The strength characteristics, failure characteristics and crack propagation of sandstone at different fracture angles are analyzed. The results show that the failure of the rock specimen undergoes several stages, such as the compacting of fractures, the initiation and propagation of microcracks, and the final destruction. When the stress increases to a certain extent, the fractures of the particles coalesce and the microcracks continue to develop. Through, the final formation of macro-cracks, making the sample instability damage. Compared with the intact sandstone samples, the mechanical parameters of the fractured sandstone samples with round holes are significantly reduced, and the decreasing amplitude is correlated with the fracture inclination; as the crack dip angle increases, the peak intensity of the sample shows an increasing feature .