The effect of particle geometry and surface asperities on the result of Discrete Element Simulations

In recent years, analysis of the behavior of brittle materials, such as concrete, rocks or granular materials, is receiving more attention. These brittle materials share common characteristics, which are their high complexity and heterogeneity, especially when they fragment from their original shape into smaller particles. Traditionally, it was common to use continuum methods (like the finite element method) to reproduce the behavior of these materials, even though these methods require complex constitutive models, which contain a lot of parameters and variables. The Discrete Element Method (DEM), originally developed by Cundall and Strack (1979), in contrast to continuum methods, has been proven to be an irreplaceable and powerful tool for conducting analysis and modelling the behavior of granular (spherical) and polyhedral (non-spherical) particle systems, which also focus on micromechanics of soil particle interactions and displacements. Meanwhile, the DEM has been proven to be suitable for analysis of continuum materials and models as well. In addition, there is another method named The Combined Finite-Discrete Element Method (FEM/DEM) (Munjiza, 2004), which is a numerical solution that focuses on the analysis of problems for solids that are considered as both continua and discontinua. This research will present the basic numerical principles of DEM and FEM/DEM, then by using these methods, the analysis of the influence of the changes of the geometry or asperities of polyhedral granular particles will be investigated. Both the influence on solution time and solution accuracy will be critically reviewed and recommendations will be given for practical use in simulations