Viability of recycled asphalt mixtures with soybean oil sludge fatty acid

• Published in: Construction & building materials Vol. 349; p. 128728
• Main Authors: de Medeiros Melo Neto, Osires, Minervina Silva, Ingridy, de Figueiredo Lopes Lucena, Leda Christiane, de Figueiredo Lopes Lucena, Luciana, Mendonça, Ana Maria Gonçalves Duarte, de Lima, Robson Kel Batista
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 26-09-2022
• Subjects: Circularity index; Custody; Mechanical performance; RAP; Rejuvenating agent; Soybean oil fatty acid; Soybean oil sludge; Rejuvenating agent; RAP; Custody; Soybean oil fatty acid; Circularity index; Mechanical performance; Soybean oil sludge
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2022.128728

•The use of 3 and 5 % SFFA as asphalt binder modifier reduced the maximum PG temperature of the virgin one.•5% SFFA indicated 40% of RAP as the viable content to the mixture by using the blending chart method.•Recycled asphalt mixtures showed a better mechanical performance and strength gain with SFFA.•The addition of RAP resulted in a higher circularity index for the recycled mixtures.•Production and recovery costs of recycled asphalt mixtures are lower than traditional mixtures.
The growing demand for advantages and energy and the increase in the economy justify the reduction of the circular environmental impact, which seeks to reduce the circular environmental impact. The use of recycled asphalt pavement (Reclaimed Asphalt Pavement – RAP) in the production of hot asphalt mixes (Hot Asphalt Mixtures – HMA) has been used in paving due to virgin materials. However, the use of high percentages to its RAP damage is susceptible to failure at low temperatures due to fatigue. The addition of rejuvenating agents can restore the properties of the recovered binder. In this sense, research that addresses solutions with industrial parts and by-products is likely to bring solutions that foster a tendency to work from a circular economy perspective, based on the economy and the circulation of waste and by-products between different sectors including engineering of paving. This work evaluated soybean oil sludge fatty acid (SSFA) at contents of 3 and 5% as a rejuvenator for recycled asphalt agents with 40% RAP, analyzing the possibility of technical, economic, and environmental feasibility. The latter, considering the potential for circularity of materials. Asphalts were mixed with mixtures for mechanical analysis through tests of resistance to attraction, susceptibility to moisture, modulus of resilient, modulus, permanent formation, and fatigue. The circularity assessment was performed through the circularity index (MCI), verifying the recycling potential of the RAP, and the net value presented (NPV) was calculated to analyze the costs of recycled asphalt mixtures. In addition to making RAP, it improved the resistance to permanent deformation, and the SSFA showed a rejuvenating effect on recycled asphalt mixtures, improving fatigue performance at the tested contents. The recycled mixtures showed the highest circularity indexes. The incorporation of accruals increased as accrued SSFA costs did not increase. Therefore, recycled asphalt mixtures proved to be more technically, environmentally, and more viable than the conventional asphalt mixture, especially the mixture with 3% SSFA.