Abstract While simulation of the drained true triaxial response of particulate assemblies using discrete element method (DEM) has caught the attention of researchers in the recent years, simulation of the undrained condition under generalized stress condition has not yet been well addressed in the literature. This treatment suggests an applicable coupled fluid-discrete element scheme to simulate the undrained response of initially anisotropic particulate assemblies under true triaxial condition. Coupled fluid-discrete element simulations highlight the combined impact of Lode angle and anisotropic microstructure of the assemblies on the effective stress paths, mobilization of shear strength, and accumulation of pore-water pressure under undrained condition. For loose assemblies suffering from flow instability, it is shown that stress ratio, mobilized friction angle, and pore-water pressure at the onset of instability depend on Lode angle.

中文翻译：

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使用 CFM-DEM 的初始各向异性颗粒组件的不排水真三轴响应

摘要 虽然近年来使用离散元方法 (DEM) 模拟颗粒组件的排水真三轴响应引起了研究人员的关注，但文献中尚未很好地解决广义应力条件下不排水条件的模拟问题。这种处理方法提出了一种适用的耦合流体-离散单元方案来模拟真正三轴条件下初始各向异性颗粒组件的不排水响应。耦合的流体-离散单元模拟强调了组件的矿脉角和各向异性微观结构对有效应力路径、剪切强度的调动和不排水条件下孔隙水压力累积的综合影响。对于存在流动不稳定性的松散组件，应力比，