A Review of Nanomaterials’ Effect on Mechanical Performance and Aging of Asphalt Mixtures

This review addresses the effects of the modifications with nanomaterials, particularly nanosilica, nanoclays, and nanoiron, on the mechanical performance and aging resistance of asphalt mixtures. The desire for high-performance and long-lasting asphalt pavements significantly pushed the modification of the conventional paving asphalt binders. To cope with such demand, the use of nanomaterials for the asphalt binder modification seems promising, as with a small amount of modification an important enhancement of the asphalt mixture mechanical performance can be attained. Several studies already evaluated the effects of the modifications with nanomaterials, mostly focusing on the asphalt binder properties and rheology, and the positive findings encouraged the study of modified asphalt mixtures. This review focuses on the effects attained in the mechanical properties of the asphalt mixtures, under fresh and aged conditions. Generally, the effects of each nanomaterial were evaluated with the current state-of-art tests for the characterization of mechanical performance of asphalt mixtures, such as, permanent deformation, stiffness modulus, fatigue resistance, indirect tensile strength, and Marshall stability. Aging indicators, as the aging sensitivity, were used to evaluate the effects in the asphalt mixture’s aging resistance. Finally, to present a better insight into the economic feasibility of the analyzed nanomaterials, a simple cost analysis is performed.