Modeling Granular Particle Shape Using Discrete Element Method

Particle morphology is an important parameter to improve our understanding of the micromechanical behavior of granular media including granular packing. This study presents a new approach of modeling granular particles of highly irregular shape using Overlapping Discrete Element Cluster (ODEC) algorithms where a series of overlapping spherical discrete elements of equivalent properties are clumped together within the particle boundary such that the resulting outline resembles the outline of actual particles. A skeletonization algorithm is developed in this study in order to automate the ODEC technique. Finally, the three-dimensional particle shapes of varying degrees of angularity are implemented within discrete element modeling software, PFC^3D using the ODEC technique, to validate the methodology by comparing the packing densities obtained with experimental measurements using X-ray Computed Tomography as well as comparing direct shear test simulation results with actual experimental measurements.