Enhancing Sustainability and Performance of Asphalt Binders: Unlocking the Potential of Unsegregated Residual Vegetable Oil

The demand for sustainable solutions in pavement engineering has prompted the exploration of innovative additives to enhance the performance of asphalt binders. This study investigates the utilization of unsegregated residual vegetable oil (RVO) as a rejuvenating agent in asphalt binders, aiming to improve sustainability and performance while addressing concerns associated with traditional recycling methods. Through a comprehensive analysis involving physical, chemical, and rheological tests, the study evaluates the effects of RVO addition on binder properties. Results indicate a significant reduction in viscosity and binder stiffness with RVO incorporation, leading to lower mixing and compaction temperatures and improved workability. Notably, fatigue analysis reveals enhanced performance at lower strain levels, suggesting improved fatigue resistance of asphalt pavements. Fourier-transform infrared spectroscopy confirms the compatibility of RVO with asphalt binders, with minimal alteration to the binder's chemical structure. Statistical analysis using ANOVA demonstrates the significance of RVO content on binder properties. Furthermore, the study establishes the feasibility of incorporating RVO into asphalt binders for the production of recycled asphalt mixtures, with RVO contents as low as 4% enabling the use of 50% reclaimed asphalt pavement. This research underscores the potential of RVO as a sustainable additive, offering promising prospects for enhancing the performance and sustainability of asphalt pavements through innovative recycling practices.