Crumb rubber modifier (CRM) produced from waste tire rubbers has been introduced into pavement engineering to modify the asphalt mixes for more than half a century. The motivation also comes from its environmental benefits from recycling scrap tires. Adding CRM into asphalt binder changes the binder microstructure and leads to a modification of the binder properties, resulting in binder aging resistance improvement. This positive result is apparent while its mechanism is still unknown. Building on the knowledge that modification of the asphalt binder alters the pavement in-service performances, it is worthwhile to study the CRM asphalt aging process from the binder phase to the mix phase, and to clarify the rubber influence on the asphalt mix performances. This study aims to investigate asphalt binder and mix aging mechanism, especially for the asphalt containing crumb rubber modifier, and evaluate the aging effects on the asphalt mix performances. This study also aims to further evaluate the performance of the asphalt mix containing crumb rubber modifier, including the rutting resistance, fatigue life, and thermal cracking resistance.
