Influence of aging, RAP content, and recycling agent on the performance of asphalt mixtures

A great complexity limits its use as the degree of aging of the asphalt binder of the RAP is a determinant for the interaction with the new binder and recycling agents to design asphalt mixtures with reclaimed asphalt pavement (RAP). One of the ways to analyze the level of interaction between the aged binder and the recycling agent is through the analysis of the performance of the mixtures after the accelerated aging of the samples in the laboratory. Thus, this paper evaluated the mechanical performance of asphalt mixtures with high contents of RAP (50%, 75%, and 100%) and organic type recycling agents (residual engine oil) and surfactant (ADCAP WM), submitted to aging protocols short and long term. The data obtained verified the feasibility of adding up to 75% of RAP in the recycled mixtures. However, detailed monitoring of its execution and performance throughout its useful life is necessary. Fatigue and flexural fracture data were highly altered by aging conditioning, evidencing the reduction in the performance of the compositions of the recycled mixtures. The statistical test showed significance for the parameters RAP content and type/content of the recycling agent used. In addition, there was an increase in the deformation capacity and better resistance to aging and cracking with the incorporation of the surfactant recycling agent.