Mechanical behaviors of rock affected by mineral particle shapes
LIU Guang1, 2, RONG Guan1, 2, PENG Jun1, HOU Di1, ZHOU Chuang-bing1
1. State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China; 2. Key Laboratory of Rock Mechanics in Hydraulic Structural Engineering; Ministry of Education, Wuhan University, Wuhan 430072, China
Abstract：The effect of mineral microstructure on macroscopic mechanical behaviors of rock as aggregates of mineral particles is remarkable. Four representative particles based on the basic theories of particle flow code are created to simulate the mineral particles in quartz sandstone. Then, sphericity is used as a particle shape factor to quantify the particle shapes. With the aid of triaxial compression tests on quartz sandstone, calibration of model parameters is performed. Then triaxial tests are performed on four kinds of rock samples formed by different particle shapes. The results show that the crack initiation stress, crack damage stress, and peak stress of samples decrease with the rising sphericity. Increasing sphericity leads to smaller elastic modulus and larger poisson ratio. And decreasing sphericity results in higher cohesion and internal friction angle. As for the rock samples made of different particle shapes, the evolvement laws of dilatancy angle with plasticity parameter are studied.
刘广, 荣冠, 彭俊, 侯迪, 周创兵. 矿物颗粒形状的岩石力学特性效应分析[J]. 岩土工程学报, 2013, 35(3): 540-550.
LIU Guang, RONG Guan, PENG Jun, HOU Di, ZHOU Chuang-bing. Mechanical behaviors of rock affected by mineral particle shapes. Chinese J. Geot. Eng., 2013, 35(3): 540-550.
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