Influence of Base Asphalt and SBS Modifier on the Weathering Aging Behaviors of SBS Modified Asphalt

Abstract

This work studied the weathering aging behaviors of styrene-butadiene-styrene copolymer (SBS) modified asphalt. The aging behaviors mainly included physical and rheological properties, chemical structure, and morphology, which were evaluated by viscosity, dynamic shear rheometer (DSR), bending beam rheometer (BBR), Fourier transform infrared spectroscopy (FTIR), and fluorescence microscope tests. The results showed that the SBS modified asphalt had the best ability to resist weathering aging compared with the single SBS modifier or base asphalt. Early weathering aging could improve the compatibility between the base asphalt and the SBS modifier and enhance the modification effect of the SBS modifier to the base asphalt. The gray relation entropy analysis indicated that during the weathering aging of SBS modified asphalt, the complex modulus aging index (CMAI) at 30°C showed the closest relationship with the degradation of the SBS modifier compared with other aging indicators.