Study on viscoelastic properties and rheological properties of SBS modified asphalt for road use with service life

SBS modified asphalt is an important material in the construction of high-grade highway, and its performance changes directly affect the pavement performance. In this study, SBS modified asphalt was extracted from the actual pavement with different service years, and the rheological properties of SBS modified asphalt with different service years were studied by macroscopic test and microscopic molecular dynamics simulation. The macroscopic test results show that the needle penetration value of SBS modified asphalt increases by 50.6 % after two years of service, and the viscosity of SBS modified asphalt increases by 54.8 % after 12 years of service. With the increase of service life, G∗ and G″ of SBS modified asphalt showed an increasing trend, and δ and G’’/G’ showed a decreasing trend. The molecular dynamics simulation results of SBS modified asphalt were consistent with the macroscopic experimental results. The rheological properties of SBS modified asphalt showed a decreasing trend with the service life, and the interfacial energies between SBS modified asphalt and aggregate also showed a decreasing trend. The research in this paper will provide a theoretical basis for the future study of the deterioration law of SBS modified asphalt and the formulation of road maintenance plan.