Study of Anisotropies Evolution in Direct Shear Test Using Discrete Element Method
Two-dimensional numerical simulations were conducted by employing the discrete element method (DEM) to study the micromechanical behavior of elliptical-shaped assembly in the direct shear test.The ELLIPSE program (Rothen burg & Bathurst 1989) was adapted and the boundary of assembly was changed to rectangular in order to simulate the direct shear box.In this study,the trend of anisotropy changes and the difference between their principal directions during shear deformation is investigated and the relations between the micromechanics parameters and average stress tensor are argued.The results demonstrate that anisotropy coefficients of soil fabric,contact normal force and contact shear force increase and rotate considerably after shearing starts and reach to their maximum value at peak state.After peak,the shear strength decreases rapidly as the anisotropies of contact normal force and contact shear force.Furthermore,mobilized internal friction angle,which is obtained by assuming non-coaxiality between anisotropy directions,shows better fit with mobilized internal friction angle obtained from average stress tensor.
direct shear test discrete element method anisotropy fabric micromechanics of soil
Morteza Naeij Ali Aaghar Mirghasemi
School of Civil Engineering,College of Engineering,University of Tehran,Tehran,Iran
国际会议
北京
英文
451-460
2012-10-15（万方平台首次上网日期，不代表论文的发表时间）