Study on the factors affecting the self-healing performance of asphalt mixture and pavement based on fracture mechanics and calculation formula

Revealed the strength changes of asphalt mixture resistance to cracking and self-healing performance under various factors, and studied the development trend of self-healing performance of asphalt mixture and asphalt pavement. Based on the J-integral principle of fracture mechanics, the evaluation index of asphalt mixture self-repairing performance was established. Through the discrete element simulation test of cyclic damage-healing and the correction of pavement temperature and load, the calculation formula of the self-healing performance of asphalt mixture and asphalt pavement is obtained. The study shows that among the main influencing factors of the self-healing performance of asphalt mixture, the longer the healing time, the better the recovery effect. In the early stage of asphalt mixture and pavement forming, the asphalt mixture has enhanced self-healing performance. Using a discrete element cyclic damage-healing simulation test, the more cyclic loading, the more initial crack generation and self-healing performance decay of the asphalt mixture, and the more the crack number curve develop nearly linearly. A well-correlated equation for fitting the self-healing performance of asphalt was obtained. Combining the influencing factors of asphalt pavement, the temperature correction factor C, the statistical traffic volume NS and the load factor f is constructed, and the formulae for calculating the self-healing performance of asphalt mixture and asphalt pavement are derived and verified. The study's results help to study the characteristics and development rules of the self-healing performance of asphalt mixture and pavement. At the same time, it can provide a reference for calculating and designing the self-healing performance of asphalt mixture and pavement.