Performance Characterization of Warm-Mix Asphalt Containing High Reclaimed-Asphalt Pavement with Bio-Oil Rejuvenator

Warm-mix asphalt (WMA) technology and recycling of asphalt pavement, i.e., reclaimed asphalt pavement (RAP), have been becoming more popular in recent years due to their economic and environmental benefits. Similarly, bio-oil rejuvenators seem to be a viable solution when the usage of high percentages of RAP is desired. However, employing a high percentage of RAP in WMA using bio-oil rejuvenator remains very limited. This experimental study investigates the use of high percentages of RAP (i.e., up to 90%) in WMA using bio-oil rejuvenator. To this end, rheological tests including rotational viscosity (RV), multiple stress creep recovery (MSCR), and linear amplitude sweep (LAS) were carried out on different combinations of binders. Wheel tracking (rutting), indirect tensile stiffness modulus (ITSM), four-point bending beam fatigue, and moisture susceptibility tests were performed to evaluate the performance of the asphalt mixtures containing different binders. Test results demonstrated that the asphalt mixture with 90% RAP and a bio-oil rejuvenator had 37% higher fatigue life and 4% improvement in moisture resistance.