沙壤土直剪试验的离散元数值模拟  

Discrete Element Simulation of Direct Shear Tests of Sandy Silt Soils

作　　者：蒋垚[1] 李艳洁[1] 徐泳[2] JIANG Yao LI Yanjie XU Yong(School of Technology, Beijing Forestry University, Beijing, 100083 School of Science, China Agricultural University, Beijing, 100083)

机构地区：[1]北京林业大学工学院,北京100083 [2]中国农业大学理学院,北京100083

出　　处：《土工基础》2017年第2期188-192,共5页Soil Engineering and Foundation

基　　金：中央高校基本科研业务费专项资金资助(2016ZCQ08);国家自然科学基金项目资助(11202031)

摘　　要：基于离散元法,用不同尺寸的球体代表土壤颗粒,添加平行粘连模型模拟颗粒间的相互作用,对沙土直剪试验进行数值研究;为了校正和验证数值模型和输入参数,将剪切结果与标准直剪试验所得的抗剪强度进行对比,结论表明离散元数值模型的仿真结果和试验能够很好吻合;还详细讨论了剪切过程中土壤颗粒的运动情况,以及剪切盒形状、剪切速度、法向载荷对剪切曲线和颗粒料床孔隙率的影响。The direct shear behavior of soil is important to the design of the mining and the agroforestry machinery. In this study, the Discrete Element Method （DEM） is adopted for the numerical investigation of the direct shear test on the sandy silt soils. The soil particles are represented by spheres of different sizes~ the interaction between particles is simulated with the tin- ear contact model; and the parallel bond model （PMB） is used to simulate adhesive interaction. To calibrate and validate the numerical model and the parameters used in this study, the shear strength values under different vertical load varying from 100kPa to 400kPa with those of the standard soil direct shear tests were compared. It is found that the DEM numerical results and the experimental results are in a good agreement. In addition, the particle movement during the shearing process was also studies; the influences of the shearing box shape, shearing velocity and normal load to the shearing curve and porosity of parti- cle bed are also discussed in detail in the paper.

关 键 词：沙壤土 直剪试验 离散元法 数值模拟 

分 类 号：TB115[理学—数学]