Impact of Aging on the Viscoelastic Properties and Cracking Behavior of Asphalt Mixtures

Aging can significantly affect the viscoelastic properties and cracking behavior of asphalt mixtures, causing increase in stiffness, reduction in relaxation capability, and increase in brittleness. Eleven mixtures are evaluated using different laboratory conditioning protocols to evaluate how the properties of asphalt mixtures, including viscoelastic properties, fatigue, and fracture behavior will change over time. Comparisons between different aging levels and mixtures are conducted by using complex modulus (E*) (field cores are included), simplified viscoelastic continuum damage (S-VECD) approach, semi-circular bending (SCB), and disk shaped compact tension (DCT) fracture tests. The climatic aging index developed by the NCHRP 09-54 project is utilized in this study to calculate the appropriate field aging duration corresponding to the different laboratory aging protocols. Pavement evaluation tools FlexPAVETM and IlliTC are also used to predict and compare the fatigue and thermal cracking performance of ...