Evaluation of Steel Slag Optimal Replacement in Asphalt Mixture under Microwave Heating Based on 3D Polyhedral Aggregate Electromagnetic-Thermal Meso-Model

Replacing conventional aggregate with steel slag waste can boost the microwave absorption properties of asphalt mixtures and reduce pollution to protect environment. In order achieve best healing in mixture, optimum particle size content are essential. For this purpose, a high-efficiency algorithm for random growth placement convex polyhedron is proposed paper. The limestone replaced an equal volume slag, three-dimensional mesoscale model mixture developed. process heating simulated by FEM. numerical simulations compared reported experimental data, which proves that reliable (R2 = 99.40%). Both average temperature uniformity distribution indicate replacement rate 60% at 4.75–9.5 mm 9.5–13.2 optimal, among heat transfer more uniform, gradient lower. Steel dramatically increase peak around boundary slag. reflection may be related dielectric constant, permeability, size. Excess will cause overheating most zones specimen also depress efficiency microwaves. coefficient variance spherical (0.36) polyhedral (0.32) temperatures indicates aggregate’s shape has negligible effect on mixtures.