Harnessing waste materials for aged asphalt binder revitalization through investigation of rejuvenation mechanism and performance enhancement

Abstract

The accumulation of waste materials presents significant environmental challenges, particularly in pavement engineering. This study investigates the possibility of using waste materials including waste cooking oil (WCO) and crumb rubber (CR) in rejuvenation and/or performance enhancement of aged asphalt binders, offering a sustainable solution. The rejuvenation mechanism was initially investigated through Fourier transform infrared (FTIR) spectroscopy and gel permeation chromatography (GPC), while the performance evaluation was carried out through multiple stress creep and recovery (MSCR), bending beam rheometer (BBR), frequency sweep (FS), and linear amplitude sweep (LAS) tests. To reveal the rejuvenation impact on performance enhancement of aged asphalt binder, significant correlations were identified between large molecular size (LMS) and sulfoxide indices with fatigue life, with a significance level below 0.05. Compared to the base binders, incorporating WCO and CR into 50% RAP illustrated better rutting resistance, critical low temperatures, and fatigue resistance at strain levels of 5% and higher. In summary, the correlation analysis suggests that chemical component parameters can be used as indicators for evaluating certain rheological properties. The findings highlight the potential of WCO and CR as effective additives for improving the performance of aged binders with high content while promoting the reuse of waste materials in sustainable pavement engineering.