Preparation and Properties of Asphalt Modified by Castor Oil-Based Rejuvenator

To ensure the performance of reclaimed asphalt binder in reclaimed asphalt pavement, this paper investigates the feasibility of using castor oil, a vegetable oil, to rejuvenate aged asphalt. The influence of castor oil on the performance of aged asphalt was evaluated through a series of tests. The results indicate that the safety of asphalt rejuvenated with castor oil meets specification requirements. Based on the findings from three key metrics, the effectiveness of the rejuvenated asphalt can be nearly returned to that of the original asphalt. Asphalt rheological testing results indicate that as the bio-oil content increases, both the high- and low-temperature characteristics of the rejuvenated asphalt progressively improve. Consequently, castor oil presents considerable potential for application as a rejuvenator in the realm of aged asphalt.