Abordagem multidimensional de misturas asfálticas com elevado teor de rap rejuvenescidas com óleo de babaçu

Abstract

The incorporation of more than 30% Reclaimed Asphalt Pavement (RAP) in asphalt mixtures faces limitations due to the high stiffness of RAP, making the use of rejuvenating additives, such as vegetable oils, necessary. In this context, babassu oil emerges as an alternative, diversifying renewable sources and reducing reliance on a single input. This study evaluated the feasibility of adding this oil to recycled mixtures through four stages: (i) physical, chemical, and rheological characterization of virgin and recovered asphalt binders modified with babassu oil contents ranging from 1% to 12%, including analysis of short- and long-term aging effects; (ii) mechanical performance evaluation of mixtures containing 0%, 15%, 56%, 63%, and 70% RAP, using indirect tensile strength, resilient modulus, moisture-induced damage, permanent deformation, fatigue, and abrasion tests; (iii) economic analysis considering production costs and net present value (NPV), as well as the influence of transportation distances; and (iv) environmental analysis based on circularity indices. The use of babassu oil resulted in reduced stiffness of the recovered binders, mitigation of thermal aging from 3% addition onward, and increased fatigue life under higher strain levels. The recycled mixtures exhibited mechanical performance comparable to the control mixture in most tests; however, the mixture containing 70% RAP and 7% oil stood out due to its superior fatigue resistance. The composition with 70% RAP and 7% oil proved to be the most circular and cost-effective, with production cost reductions of up to 72.98% per paved kilometer. The integrated analysis of circularity, costs, and CO₂ emissions highlighted the potential of babassu oil to enhance the efficiency and sustainability of recycled mixtures.