Impact of Engine Oil as a Rejuvenator on the Properties of RAP Containing Asphalt Mixtures

Civil Engineering Department, Faculty of Engineering, University of Kufa, Al-Najaf, Iraq

^a* Corresponding author malkuzae@gmail.com
^b abbas.alhadabi@uokufa.edu.iq2

Abstract

In order to build roads in more sustainable and environmentally friendly ways, reclaimed asphalt pavement (RAP) must be used in large quantities. Using RAP, new asphalt can be produced with a small amount of raw materials, thus reducing the energy required to extract and refine new materials and the waste generated from demolishing old asphalt pavements. The high stiffness of RAP mixtures can make it difficult to use RAP in amounts greater than 30%. Several methods can be used to overcome this difficulty, one of which is the addition of rejuvenating agents. Therefore, this study investigated the possibility of using pure engine oil (PEO), studied its effect as a regenerating agent for RAP, and determined the optimal percentage of PEO. Three percentages of RAP were used to demonstrate the viability of using high percentages of RAP in the asphalt mixture: 25%, 50%, and 75%. In addition, four PEO percentages were tested, namely 2, 4, 6, and 8%, to determine the ideal amount that helps the RAP regain its properties. The research revealed that RAP is appropriate for hot asphalt mixtures, producing results that outperformed the virgin mixture. Furthermore, the optimal PEO percentage ranged between 4% and 6%. This study concluded that employing RAP in significant quantities in addition to PEO while sustainably building roads is feasible.