Quantitative distribution characteristics of force chains for asphalt mixtures with three skeleton structures using discrete element method

Abstract

Three digital specimens of asphalt mixtures (AC-13, SMA-13 and OGFC-13) were reconstructed to conduct a virtual simple performance test using the discrete element method. The distribution characteristics of force chains were investigated by a statistical method. The results indicate that it is reasonable and feasible to analyze the mesoscopic responses of asphalt mixtures using digital models. The probability distribution of the normal force chains varies with loading time and the variation laws are consistent at four loading times. And the probability distribution of the shear force chains decays exponentially. Besides, the maximum probability distributions of the normal and shear force chains decrease with increasing timestep. OGFC-13 has the maximum probability distributions of the normal and shear force chains, which are 0.34186 and 0.55884, respectively. The proportions of the “strong” force chains decrease over the loading time, and AC-13 has a maximum proportion of 49.41% for the three asphalt mixtures at four loading times. In addition, the angle distributions of the force chain are mainly near 90°, and the average ratio of the normal contact force to the mean normal contact force increases with increasing loading time at 90°. Finally, the angle distribution proportions in the first and second quadrants are much greater than those in the third and fourth quadrants.