Rheological and Spectroscopic Properties of Ethylene Vinyl Acetate–Modified Rubberized Asphalt

Abstract

The effect of ethylene vinyl acetate (EVA) on the aging properties and rheological properties of rubberized asphalt was measured in this paper to identify the optimum proportion of EVA combined with waste tire rubber (WTR) modified asphalt. Aging methods of thin-film oven test (TFOT) and pressure aging vessel test (PAV) were conducted to imitate the different degrees of the aging process. At first, frequency sweep at different temperatures was carried out to construct the construction of G* master curves, following the time-temperature superposition principle, to evaluate the aging sensitivity. The black diagram was depicted to compare the rheological behavior of different asphalt binders. The calculation of the WLF equation based on the shift factor of master curves was conducted to calculate the values and aging index of 15°C DSRFn to assess the resistance to fatigue cracking at the intermediate temperature. Then, zero shear viscosity (ZSV) and rutting factor (G*/sinδ) at 60°C were also used to calculate the aging index, because these both are measurements of resistance to rutting deformation at high temperature. Finally, the microstructure of unaged and aged asphalt binder was studied by Fourier transform infrared spectroscopy (FTIR). The relationship between rheological and chemical indexes was studied. The results show that 15%WTR+4%EVA has the best antiaging performance, and EVA can reduce the aging sensitivity of different parameters, especially in the high-temperature area.