Micromechanical modelling of aggregate–aggregate interactions with distinct particle element method for virtual laboratory simulation

Road pavement performances are still not fully understood because it has been necessary to simplify its materials behavior, modeling them as continuous. In reality, however, they exhibit discontinuous performances, which do not always fit for the advanced continuum models based on non-linear behavior very well. To overcome this limitation, the Distinct Particle Elements Method (DEM), which schematizes a granular material by particles that displace independently from one another and interact only at contact points, becomes a good answer. In this way, in fact, is possible to analyze the discrete character of mixes through a microscopic approach. The author in a previous study have confirmed the DEM potentialities in the investigation of the fatigue performances of asphalt mixes and have observed the great influence of particles geometry on the materials response. So, in this paper, in order to deepen the effects of aggregate shape and dimensions on the fatigue behavior of a road pavement, several triaxial laboratory compression tests on specimens of steel particles have been simulated and the numerical results have been compared with the lab ones.