Three-dimensional distinct element analysis of mechanical properties of structured sands
JIANG Ming-jing1, 2, 3, 4, SHI An-ning1, 2, LIU Jun3, 4, ZHANG Fu-guang5
1. Department of Civil Engineering, Tianjin University, Tianjin 300072, China; 2. State Key Laboratory of Hydraulic Engineering Simulation and Safety, Tianjin University, Tianjin 300072, China; 3. State Key Laboratory of Disaster Reduction in Civil Engineering, Tongji University, Shanghai 200092, China; 4. Department of Geotechnical Engineering, Tongji University, Shanghai 200092, China; 5. School of Civil Engineering, Shijiazhuang Tiedao University, Shijiazhuang 050043, China
Abstract：The three-dimensional (3D) distinct element method (DEM) is employed to investigate the behaviours of cemented sands at the macro-scale in triaxial tests. A 3D bond contact model is implemented in a DEM commercial software (PFC3D) to simulate the triaxial tests on cemented specimens, and the simulated data are compared with the experimental results. Finally, the underlying mechanism behaviour is discussed at the macroscopic scale. The DEM results show that, the structured sands and uncemented loose sands have different macroscopic behaviours. In the conventional triaxial compression tests, the strain softening and the shear dilation are more pronounced in the structured sands with the increasing cement content or decreasing confining pressure. Under high confining pressures, the specimens show strain hardening and shear contraction. Both the cohesion and the peak friction angle increase with the increasing cement content under relative low-mean stresses. As the mean stress increases, the strength envelops for cemented sands converge gradually to those for uncemented geomaterials.
蒋明镜, 石安宁, 刘俊, 张伏光. 结构性砂土力学特性三维离散元分析[J]. 岩土工程学报, 2019, 41(S2): 1-4.
JIANG Ming-jing, SHI An-ning, LIU Jun, ZHANG Fu-guang. Three-dimensional distinct element analysis of mechanical properties of structured sands. Chinese J. Geot. Eng., 2019, 41(S2): 1-4.
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