Avaliação do comportamento mecânico de misturas asfálticas com substituição parcial por RAP

Abstract

The Brazilian transportation matrix is predominantly road-based, with more than 60% of freight and 90% of passengers being transported via highways. However, more than 50% of the 213,500 km of paved roads are in fair to poor surface condition, requiring rehabilitation interventions. In this context, a commonly used alternative is the milling of the old asphalt pavement, which results in Reclaimed Asphalt Pavement (RAP), a material composed of aggregates and aged asphalt binder. The reuse of RAP in the production of new asphalt mixtures offers economic and environmental benefits, by reducing the extraction of natural resources and minimizing the generation of unusable waste. Thus, this study aimed to evaluate the influence of replacing part of the coarse fraction of an asphalt mixture with RAP, for different binder contents. For this evaluation, HT-IDT (High Temperature Indirect Tensile) and IDEAL CT (Indirect Tensile Asphalt Cracking Test) were performed to analyze the propensity for permanent deformation and susceptibility to fatigue cracking. The main conclusion of the study is that the incorporation of RAP is technically feasible, with the recycled mixtures showing equivalent — and in some cases, superior — performance compared to conventional mixtures, especially regarding cracking potential. However, attention must be paid to resistance to permanent deformation, due to the possible increase in effective binder content.