Characterization of artificial spherical particles for DEM validation studies

This paper describes a study in which advanced particle-scale characterization was carried out on spherical shaped particles that can be used in experimental tests to validate Discrete Element Method (DEM) simulations. Two types of particle, alkaline beads and borosilicate beads, which are manufactured from two different materials were considered. The particle shapes, stiffnesses, contact friction properties and surface roughnesses were measured. The influences of hardness and roughness on the mechanical response of the particles were carefully considered. In comparison with the alkaline beads, the borosilicate glass beads had more uniform sizes and were more spherical. They also exhibited mechanical characteristics that are closer to natural quartz sand. While consideration is restricted to only two material types here, the work has a broader implication, as a methodology for selecting particles suitable for use in DEM studies is outlined and the key parameters that should be considered in the selection process are highlighted.