Evaluation of Physicochemical and Rheological Properties of Terminal Blend Rubberized Asphalt Incorporating Polymer

Waste tires, used in combination with polymers, have been extensively employed in the construction of asphalt pavements. The performance of these hybrid asphalts varies depending on the manufacturing process, the characteristics of the neat binder, and other factors. The present study aims to investigate the effect of crumb rubber, polymer, and neat asphalt on physicochemical and rheological properties of terminal blend rubberized asphalt (TBRA). Thermal gravimetric (TG) testing was performed to analyze the component distribution of different crumb rubber modifiers (CRMs). Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), and solubility and storage stability tests were used to characterize the physicochemical properties of TBRA binders. The rotational viscosity (RV) test, high-temperature performance grade (PG), and rheological master curve were used to compare the rheological properties of various TBRA binders, respectively. Results indicated that crumb rubber and neat binder characteristics, as well as the addition of polymer, impact TBRA performance. However, the influence of neat binder and polymer is more significant than that of crumb rubber. The primary differences in the physicochemical properties of TBRA prepared with different crumb rubber types are related to solubility and degradation degree. The interaction between Zhonghai neat asphalt and crumb rubber is weaker than that of ESSO and Jinshan asphalt, as evidenced by a comparison of molecular weight distribution. Moreover, 3.0% styrene-butadiene-styrene (SBS) polymer can significantly improves the elastic property of TBRA produced with ESSO neat asphalt, which is evidenced by similar phase angle plateau region with 4.5% SBS modified asphalt.