Abstract: This paper presents results of three-dimensional simulations of the hollow cylinder test using the discrete element method (DEM). To verify the capability of numerical model, the hollow cylinder specimens are sheared at different principal stress directions. The localization in the specimen are examined in terms of the distributions of stresses and strains. The force chain formation and collapse during the loading are visualized. Meanwhile, the formation of the shear bands in the different shearing directions is characterized by porosity and shear strain rate distributions in the samples. The results show that the shear strain rate contour is a better indicator for shear band development than the porosity contours. To explore the micro behavior of the specimen, the evolutions of coordination number and particle rotation at different locations in the sample are also monitored. It is proved that 3D DEM technique can capture the macro-micro behavior of specimen in the complex stress path, which facilitate the interpretation of the stress-strain behavior from physical lab tests.

Key words: discrete element method, hollow cylinder apparatus, shear band, fabric