Comprehensive Fatigue Mechanism of Asphalt Mixtures: Synergistic Study of Crack Initiation and Propagation

This study investigated the fatigue cracking mechanism of asphalt mixtures by synergizing crack initiation and propagation at varying temperatures and mix variants. An advanced approach to the dynamic semicircular bending (SCB) test was utilized to evaluate the fatigue mechanism of 18 asphalt mixtures totaling 648 SCB specimens. Based on crack growth and crack mouth opening displacement analyses, distinctive cracking mechanisms were recorded for three different asphalt mixture types. Further, predictive models were developed to estimate the different stages of fatigue based on fundamental materials properties. Overall, the adopted methodology conveniently distinguished cracking characteristics with respect to crack initiation and propagation at different temperatures. (C) 2018 American Society of Civil Engineers.