Evaluation of critical voids in asphalt mixture under microwave self-healing process

This work analyzes the void change of asphalt mixture during self-healing process. The results show that the void has obvious scale effect, and the void of different scales is completely different in area proportion, growth and iterative change rate. The key voids in the freeze-thaw stage are small voids (<2mm²). The key voids in the healing stage are small voids and big voids (>4mm²). This work has a positive effect on construction of long-life durability pavement.