Investigation on Possibility of Waste Vegetable Oil Rejuvenating Aged Asphalt

In order to guarantee the service performance of recycling asphalt mixture with reclaimed asphalt pavement (RAP), asphalt rejuvenator shall be added. In the last five years, vegetable oil-based rejuvenators have received more and more attention due to their green and regenerative advantages. The object of this paper is to investigate the feasibility of rejuvenating aged asphalt by a kind of waste vegetable oil (W-oil). The effect of W-oil on the performance of aged asphalt is characterized by a safety property test, aging property test, and pavement performance tests; the pavement performance tests included traditional tests and a rheological test. The results show that both the safety property and aging property of rejuvenated asphalt with W-oil meet the specification requirements. According to the results of traditional performance indexes (i.e., penetration, soften point, and ductility), the pavement performance of rejuvenated asphalt can be recovered to the level of virgin asphalt. According to the results of performance indices obtained from the rheological test, the optimum dosage of W-oil is determined to be 13.4 wt %. Compared with virgin asphalt, the rutting property of rejuvenated asphalt is equivalent to that of virgin asphalt, and the workability is slightly poorer; however, the fatigue property and low temperature property have been significantly enhanced. W-oil cannot only improve the pavement performance of aged asphalt, it can also guarantee good safety property and aging property. Therefore, W-oil is of great potential to serve as an asphalt rejuvenator for rejuvenating aged asphalt.