Study on waste engine oil and waste cooking oil on performance improvement of aged asphalt and application in reclaimed asphalt mixture

This paper studies the effects that varying amounts of waste cooking oil (WCO) and waste engine oil (WEO) have on the rejuvenation effect of aged asphalt, and the road performance of the 7% compound regenerant to different contents of RAP. The basic performance tests demonstrated the regeneration effect of waste oil, while the microscopic test and chemical composition analysis revealed the regeneration mechanism, after which the road performance was then tested using RAP. Moreover, the study outcome demonstrates that adding appropriate waste oil dosage can effectively increase the conventional physical properties. Furthermore, it was revealed that due to the addition of waste oil supplementing the light components of the aged asphalt, the basic performance of asphalt at different aged degrees can be restored to the standard. Meanwhile, the addition of waste oil will not cause other chemical reactions, but excessive waste oil addition will lead to undesirable reduction in the viscosity of the asphalt, so the recommended waste oil dosage is 1%~4%. In the end, subsequent road performance tests showed that the compound regenerant can achieve 45% RAP application.