Study on the effect of carbon nanotubes on the properties of wasted engine oil recycled asphalt binder

Abstract

A large amount of reclaimed asphalt pavement mixture (RAP) is produced in the process of pavement maintenance. By mixing RAP, wasted engine oil regenerant, new asphalt binder and new aggregate in a certain proportion, recycled asphalt mixture can be produced. This saves a lot of resources and costs, but the wasted engine oil recycled asphalt binder (RAS) has problems such as instability, easy aging and decreased adhesion. In this paper, carbon nanotubes were used to modify RAS. We find that carbon nanotubes can improve the softening point, ductility and viscosity of RAS. In addition, the thermogravimetry (TGA) test results show that carbon nanotubes can significantly improve the thermal stability of RAS. The initial decomposition temperature of RAS containing carbon nanotubes can reach 336.84℃, which is 11.84℃ higher than that of the RAS. At the same time, the decomposition temperature of the lightweight component is significantly increased by 17℃ compared to the pristine asphalt binder. The results of UV aging experiment show that carbon nanotubes can effectively delay the UV aging process of RAS. The results of mechanical drawing test and ultrasonic boiling test confirm that carbon nanotube improves the adhesion property between the RAS and the aggregate, and then improves the water damage resistance of the RAS. The adhesion of RAS improves significantly when the carbon nanotubes content is 1.5wt%. In general, carbon nanotubes have a good application potential to improve the performance of RAS.