Uso de resíduo de polietileno de média densidade como modificador do ligante asfáltico CAP 50/70

Abstract

Asphalt paving in Amazonas faces performance limitations due to increasing heavy traffic and regional climatic demands, while the management of industrial solid waste generated in the Manaus Industrial Pole (PIM) requires alternative reuse strategies. This study comparatively evaluated the performance of asphalt mixtures containing reclaimed asphalt pavement (RAP), produced with conventional CAP 50/70 binder and binder modified with medium-density polyethylene (MDPE) waste from geomembrane manufacturing at PIM, at contents of 3%, 5%, and 7% by binder mass. The modified binders were characterized through penetration, softening point, and flash point tests, whereas the asphalt mixtures were evaluated using the Marshall mix design method and indirect tensile strength tests. The results showed a 61.5% reduction in penetration and a progressive increase in softening point, reaching 129.2°C at the 7% MDPE content, indicating the occurrence of matrix inversion. Flash point increased linearly, and all modified binders complied with ANP Resolution No. 897/2022. The modified mixtures exhibited increases of up to 152.5% in Marshall stability and 57.1% in indirect tensile strength compared with the reference mixture. However, the air void content remained above the limit established by DNIT 031/2024. It is concluded that the incorporation of 7% MDPE provided the best mechanical performance, demonstrating technical potential for asphalt pavements in the Amazon region while promoting the sustainable reuse of industrial waste in accordance with circular economy principles.