Evaluation of the Rheological Behavior and the Development of Performance Equations of Asphalt Composites Produced with Titanium Dioxide and Zinc Oxide Nanoparticles.

This research evaluated the rheological behavior of conventional asphalt binders modified with TiO 2 and ZnO nanoparticles and proposed mathematical equations for performance prediction. First, composites were evaluated at high temperatures to investigate the Performance Grade (PG), non-recoverable creep compliance, and Aging Index (AI). Subsequently, the fatigue damage tolerance was determined at a temperature of 20 °C through the Linear Amplitude Sweep (LAS) test. At high temperatures, for both nanoparticles, stiffness gain was observed as the nanomaterial content increased, evidenced by the increase in the dynamic shear modulus. This resulted in an increase in the Performance Grade and reduction in non-recoverable creep compliance, leading to greater resistance to permanent deformations. Furthermore, it was found that nanoparticles were able to reduce the effects of oxidation of the asphalt matrix, corroborated by the reduction of the Aging Index (AI). Regarding the fatigue damage tolerance, for both nanoparticles, an increase in performance was observed at low deformation amplitudes and a decrease at high deformation amplitudes. Finally, the analysis of each rheological parameter allowed to define the mathematical equations capable of predicting the performance of conventional asphalt binders when modified with nano-TiO 2 or nano-ZnO.