Performance of Asphalt Binders and Mixtures Incorporating Reclaimed Asphalt Pavement with Waste Cooking Oil as Rejuvenator

Abstract

Recycled asphalt pavement (RAP) and waste cooking oil (WCO) are considered waste materials with significant adverse effects on the environment. In this study, WCO is investigated as a rejuvenator to incorporate different RAP contents in hot mix asphalt (HMA). The performance of rejuvenated binders and recycled mixtures with optimal doses of WCO is investigated considering rutting, fatigue, and durability characteristics. The binders without WCO depicted significantly higher rutting resistance and poor fatigue life as determined from the linear amplitude sweep (LAS) test. Performance tests showed that recycled mixtures (RA mixtures) with various RAP contents tested at the ideal WCO content and demonstrated rutting and cracking resistance on par with HMA. Additionally, due to the acidic nature of WCO and asphalt, there is an increased affinity for moisture, which leads to moisture damage. Consequently, the moisture susceptibility of recycled mixtures containing WCO was evaluated. Correlations were developed between the rheological characteristics of rejuvenated binders and RA mixtures with WCO. This study recommends incorporating WCO methodically to improve the performance of HMA using various RAP contents. Dry addition of WCO can mitigate moisture susceptibility of recycled mixtures at a higher degree than when using a wet method, and this resistance can be further enhanced using antistripping agents. This study investigates a significant way to build road infrastructure with sustainability. It demonstrates a simple yet rational method to tackle two environmental concerns related to recycled asphalt pavement (RAP) and waste cooking oil (WCO) by employing WCO as a rejuvenator in recycled hot mix asphalt (HMA). This study reveals that integrating WCO into RAP formulations significantly enhances the performance of rejuvenated binders and recycled mixtures (RA mixtures) with optimal WCO doses. This innovation leads to RA mixtures exhibiting comparable rutting, durability, and cracking resistance to conventional HMA while addressing environmental challenges associated with RAP and WCO. For practitioners and stakeholders in construction and infrastructure, implementing this method presents a sustainable solution to enhance asphalt performance while effectively managing wastes. By incorporating WCO strategically, pavements can be constructed or rehabilitated with the utilization of different RAP contents, promoting environmental sustainability without compromising performance. This research offers a practical pathway for the asphalt industry to embrace a greener approach, potentially revolutionizing road construction practices and contributing to an ecofriendlier infrastructure landscape.