Numerical Investigation of the Cushion and Size Effects During Single-Particle Crushing via DEM

This paper uses the discrete element method to model the size and cushion effects during single-particle crushing tests. We propose simplified numerical modeling to examine the effects of particle size and coordination number on particle breakage behavior. We validate the proposed modeling by comparing the numerical results with the experimental data reported in the literature, in terms of the variability of particle tensile strength and axial force-displacement responses. Based on the numerical results, it is clear that a larger particle size entails a higher tensile strength with a larger discreteness. In addition, the characteristic tensile strength increases linearly with an increasing coordination number. Moreover, smaller particles are more susceptible to the cushion effect than larger particles. The numerical results also indicate that an increasing coordination number induces a more ductile mode of failure. Based on these results, we propose an empirical equation for calculating tensile strength, incorporating both the cushion effect and the size effect.