Exploration of the Potential Prospect of Rare Earth Compounds in the Antiaging of Asphalt

In order to mitigate the effects of thermal-oxidative and ultraviolet (UV) aging on asphalt pavements during service, we explored the influence law of rare earth compounds on the aging properties of asphalt and the antiaging mechanism. The asphalt was subjected to thermal-oxidative and UV aging tests by using a thin-film aging oven as well as a UV aging oven. The changes of macroscopic and microscopic properties of three rare earth–modified asphalts before and after aging with base asphalt were studied by using basic physical property tests, dynamic shear rheology tests, and Fourier infrared spectroscopy comparisons. The results showed that the rare earth–modified asphalt had significantly improved in deformation resistance and high-temperature stability compared with the base asphalt. After aging, the change of carbonyl and sulfoxide functional group indexes of rare earth–modified asphalt was significantly slowed down compared with the base asphalt. It showed that the incorporation of rare earth compounds has a direct effect on the improvement of the aging resistance of asphalt. Regarding the three types of rare earth–modified asphalt, cerium oxide–modified asphalt showed better improvement in thermal-oxidative and UV aging resistance.