Evaluation of the Viscoelastic Characteristic of Asphalt Binder with Dry–Wet Cycle Aging.

The rainy season in hot and humid areas can cause various diseases to weaken the performance of asphalt pavement. To determine the influence of rainfall on the viscoelastic properties of asphalt binder, a dry–wet cycle aging method was used to simulate the aging behavior of Gaotong base asphalt binder (GBA) and styrene–butadiene-styrene (SBS) modified asphalt binder (SBSMA), and the complex shear modulus, fatigue characteristics, and creep compliance of binders during dry–wet cycle aging were studied. The results show that the complex modulus of binders raised with the increase of dry–wet cycles time. Further, according to the simplified viscoelastic continuous damage (S-VECD) model, the damage of aged binders went up while the integrity went down sharply. Moreover, the fatigue life of SBSMA was greatly affected by aging, still far better than that of GBA. The fatigue parameters had a certain correlation with the complex modulus and they could predict the fatigue characteristics of aged binders. The creep recovery rate of GBA increased with the increase of the dry–wet cycle aging time, opposite to SBSMA. Furthermore, compared with thermal oxidative aging, the damage to the asphalt binder was worse in the later stage of dry–wet cycle aging because of the dissolution of the polar groups of binders and the continuous exposure of new surfaces. [ABSTRACT FROM AUTHOR]