非饱和重塑黄土的一种简化离散元模型

黄土是一种水敏性颗粒材料，其强度受含水率影响十分明显。基于非饱和土力学的基本理论，利用颗粒离散元方法，建立了一种非饱和黄土的简化离散元模型。在对非饱和黄土的力学特性进行离散元模拟分析后，与室内三轴试验进行了对比验证。对比模型和试验结果发现：不同含水率试样的应力应变关系受土体颗粒间摩擦系数直接影响，表现为试样含水率越高，摩擦系数越小，说明该离散元模型在一定范围内能够反映重塑黄土的土力学特性。

A simple discrete element model of unsaturated remodeling loess

Loess is a kind of water sensitive granular material, and its strength is obviously affected by wa-ter content. Based on the basic theory of unsaturated soil mechanics, a simplified discrete element model of unsaturated loess is established by using the discrete element method. After analyzing the mechanical charac-teristics of unsaturated loess, the triaxial test was carried out for verification. After comparison of the re-sults from the model and experiments, it is found that the inter-particle friction coefficient influences the strain-stress relationship with different water contents. In other words, samples with higher water content could be simulated by lower internal friction coefficient in DEM. This, to some extent, shows that the DEM model in this paper could reflect the soil mechanics properties of unsaturated remodeling loess.