Micromechanical Considerations of Particle Breakage Using Discrete Element Method

Using DEM (Discrete Element Method), a model is presented to simulate the breakage of two-dimensional polygonshaped particles. In this model, shapes of the particles generated after breakage are predefined and each uniform (uncracked) particle is replaced with smaller inter-connected sub-particles. If the bond between these sub-particles breaks, breakage will happen. With the help of this model, it is possible to study the influence of particle breakage on macro and micro mechanical parameters. In this simulation, the evolution of microstructure in granular assemblies can be seen by tracing of coordination number during the shear process. Also variation of contact normal, normal force and tangential force anisotropy can be tracked. For this purpose, two series of biaxial test simulations (breakage is enabled and disabled) are conducted on assemblies of two-dimensional polygon-shaped particles and the results are compared. It is found that the simulation results are in good agreement with observations obtained from experimental tests.