High-Temperature Rheological Behavior and Fatigue Performance of Montmorillonite-Modified Asphalt

In this research, the effects of modifiers on the high-temperature rheological and fatigue properties of asphalt were investigated by utilizing montmorillonite (MMT) and organic montmorillonite (OMMT) as modifiers for 70# and styrene butadiene styrene (SBS) asphalt, respectively. Temperature scanning tests and linear amplitude scanning (LAS) tests were performed using a dynamic shear rheometer (DSR) to evaluate the viscoelasticity, rutting resistance, and fatigue properties of the asphalt binder. The rheological properties under high-temperature and high-frequency conditions were also characterized by the Black curve and Cole–Cole transformation. Additionally, the elastic properties of the asphalt were examined using nanoindentation (NI). The results of the DSR tests indicate that the incorporation of MMT/OMMT into asphalt enhances its elastic properties and reduces its viscous properties, leading to improved resistance to shear deformation, rutting, and fatigue. Moreover, the NI tests show that the addition of MMT or OMMT improves the elastic properties of the asphalt, while also validating the effectiveness of nanoindentation in assessing the viscoelasticity of asphalt.