Study on mesoscopic model of low-temperature cracking of steel slag asphalt mixture based on random aggregate

In order to establish a numerical model of asphalt mixture heterogeneity close to reality, a random aggregate model was established by the discrete element method (DEM). It can reflect aggregate sphericity, angularity, roughness, and gradation characteristics. The three-point bending test of the simulated beam was used to explore the expansion mechanism of the I-type crack of the steel slag asphalt mixture (SAM). The results showed that the angularity of the steel slag aggregate is more minor than basalt, the stress concentration at the corner is less, and the number of aggregate cracks Ng is small. The crack expands violently along the basalt aggregate, and the low-temperature crack resistance of SAM is better than the basalt asphalt mixture (BAM).