Research on asphalt mixture force chain identification criteria based on computational granular mechanics

Abstract

The difference in force chains can be used to evaluate asphalt mixture skeleton structure. In this study, different asphalt mixture discrete element method models were established via the two-dimensional particle flow code software to analyze force chain identification criteria. And then, the force chain lengths of different asphalt mixtures were quantified preliminarily. Results indicate that the average contact force [Formula: see text] needs to be set as the contact force threshold value. The recommended angle threshold value is 45°. For asphalt mixtures, less than 50% aggregate content is involved in transferring external loading. Whether the aggregate is located on the force chains should be regarded as an important criterion to judge whether the aggregate is involved in the asphalt mixture skeleton composition. Although dense-graded asphalt concrete will generate many force chains, most of them are short length force chains that are not conducive to transferring load.