基于颗粒流的花岗岩微观破坏机制研究

Study on Granite Micro Failure Mechanism Based on Particle Flow Code

为研究岩石在单轴压缩条件下的微观破坏机制,利用岩石力学试验机进行花岗岩岩样的室内试验,采用颗粒流分析程序编程建立可靠的数值模型,通过分析试件压缩破坏过程的裂纹演化规律、裂纹数特征和能量耗散规律,讨论其微观破坏机制。结果表明,花岗岩岩样内部拉裂纹分布与宏观破坏面较为吻合,在裂隙发展中起着关键作用;峰值强度前,剪裂纹较拉裂纹发育显著,峰值强度后,拉裂纹数剧烈增加,造成岩样承载力的降低;岩样最终失效形式为沿对角形成宏观剪切面破坏,并有少量张拉襞裂破坏。

For studying the micro failure mechanism of rocks under the condition of uniaxial compression,the rock mechanics testing machine is used to test the granite samples in indoor laboratory,and the particle flow analysis program is used to establish a reliable numerical model to analyze the crack evolution law,crack number characteristics and energy dissipation law of specimen compression failure process,and the micro failure mechanism of rock is discussed.The results show that the tensile crack distribution in the granite sample is in good agreement with the macroscopic failure surface and plays a key role in the fracture development.Before the peak strength,the shear crack is more developed than the tensile crack,and after the peak strength,the number of tensile crack increases sharply,resulting in the decrease of rock sample bearing capacity.The final failure mode of rock sample is to form macroscopic shear plane failure along the diagonal with a small amount of tensile cracking failure.