Effects of Mixing Ratio of Old and New Asphalt on Aging Characteristics of Asphalt Cement

Abstract

In order to explore aging characteristics of asphalt cement, the stiffness modulus, creep rate, phase angle and loss modulus of new and old asphalt mixture and recycled asphalt before and after RTFOT & PAV aging were tested by BBR and DSR experiments. The results showed that the modulus, creep rate and phase angle of asphalt cement was effected by RTFOT slightly, while they were effected by PAV relative significantly. After RTFOT and PAV aging, stiffness modulus, creep rate, phase angle and loss modulus of all asphalt samples have undergone significant changes, furthermore, with the increase of recycled asphalt content, the technical indexes(stiffness modulus, creep rate, phase angle and loss modulus) tended to those of pure recycled asphalt. Thereafter, the process of RTFOT and PAV aging of new asphalt may be catalyzed and accelerated by the recycled asphalt on a certain extent.