Analysis of influencing factors for self-healing of fatigue performance of asphalt rubber mixture

NfNM method of ASTM D7460 was chosen as asphalt mixture's fatigue failure criterion, and single factor comparative analysis and indoor four-point bending fatigue test were used to fulfill a systematic study on the main factors which affect the self-healing capacity of fatigue performance of asphalt rubber mixture. These factors were the amount of asphalt, damage, crumb rubber content, void ratio of mixture, strain, self-healing time, self-healing temperature and load. The fatigue behavior equation of asphalt rubber mixture with self-healing compensation considered was regressed out. The results show that the fatigue self-healing efficiency is proportional to the amount of asphalt and self-healing time, inversely proportional to the extent of the damage, void ratio of mixture and strain, and when the crumb rubber content is 20%, self-healing temperature is 60 °C, and load is 5 kPa, fatigue self-healing efficiency achieves optimum results; there is a good correlation between the amount of asphalt and void ratio of mixture with self-healing compensation and strain considered.