Feasibility study on recycled vegetable oil waste and recycled polyethylene for the modification of aged asphalt

The application of reclaimed asphalt pavement has been widely encouraged due to its significant economic and environmental benefits. However, it is necessary to add rejuvenators to ensure its performance. Currently, bio-oil-based regenerants have attracted attention owing to their advantages of renewability and cost savings. The purpose of this paper is to study the use of recycled vegetable oil waste (R-oil) and recycled polyethylene particles for the regeneration and modification of aged asphalt. Physical, rheological, and chemical tests were used to figure out their influence on the pavement performance of aged asphalt. According to the physical test indices (penetration, softening point, and ductility), the performance of the rejuvenated asphalt was better than that of virgin asphalt. The workability and low-temperature performance of the rejuvenated asphalt were basically the same as those of virgin asphalt, and its fatigue and high-temperature performance were better. Infrared spectroscopy showed that R-oil diluted the high-polarity sulfoxide base of aged asphalt. Gel permeation chromatography showed that its molecular weight dispersion was better than that of aged asphalt. Therefore, R-oil and polyethylene can improve the pavement performance and chemical properties of aged asphalt.