Rheology and Micromechanical Analysis of Granular Media Composed of Platy Particles: A Step Toward the DEM Simulation of Clayey Soils

This work was carried out in the framework of a larger project devoted to the micro-mechanical modeling of clayey soils by means of discrete element simulations. Here, we study the rheology and microstructure of granular media composed of platy particles. The particles are three-dimensional square plates, approximated as spheropolyhedra. Several samples composed of particles of different levels of platyness (related to the ratio of length to thickness) were numerically prepared and sheared up to large deformations. Specifically, we revisit and analyze in detail an ordering phenomenon described briefly in a previous paper [1] and investigate its consequences in terms of the alignment of particles and cluster formation. We find that particle alignment is strongly enhanced by the degree of platyness and leads to the formation of face-connected clusters. Due to dynamics, this spontaneous clustering is a robust characteristic of granular systems composed of platy particles even in the absence of attraction forces.