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Concern for the environment has been increasingly evident in recent years, knowing that one of the main environmental problems found in urban centers is associated with the urban heat island phenomenon. In view of this environmental problem, one way to obtain cooler paved surfaces under the incidence of solar radiation is to increase their albedo, through the coloring of paved surfaces. Thus, the objective of this work was to investigate the potential of using waste high-density polyethylene (HDPE) waste to color asphalt mixture and minimize the urban heat island phenomenon due to the high reflection of HDPE colors. The research was structured in three main strands: (i) rheological characterization of the binder modified by HDPE in the contents of 1%, 2%, and 3%; (ii) mechanical analysis of asphalt mixtures with HDPE; (iii) evaluation of the use of HDPE on the asphalt surface and its contribution to the reduction of surface temperature. A statistical Student's t test verified the significance of the mechanical performance data of the mixtures. The results showed that the addition of 2% of HDPE contributed to the asphalt binder presenting rheological benefits at high temperatures and, consequently, a gain in the mechanical performance of the asphalt mixtures. The use of HDPE on the asphalt surface provided a reduction in surface temperatures, which could be a contributing agent in the reduction of urban heat islands. [ABSTRACT FROM AUTHOR]

Modification of asphalt binders incorporating polyethylene terephthalate (PET) residues can improve their physical and rheological characteristics while providing secondary environmental benefits. This study evaluated the result of the addition of Micronized PET (MPET) in the contents of 2 and 3% in Petroleum Asphalt Cement with 50/70 penetration (PAC 50/70). The binder properties were evaluated through penetration tests, softening point, rotational viscosity, ductility, infrared spectroscopy, performance grade, and multiple stress creep recovery. The results showed that this modifier provided an increase in the softening point and viscosity, a decrease in penetration, an improvement in permanent deformation and fatigue life. The contents used in this research did not show a significant increase in mixing temperatures. The modifier showed the antioxidant property. Overall, 3% of MPET had the best results in the tests performed. It was concluded that the use of MPET as an asphalt binder modifier is an effective method to improve the properties of the asphalt binder while addressing an environmental concern and preserving natural resources. [ABSTRACT FROM AUTHOR]

• 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. [ABSTRACT FROM AUTHOR]