Improved approach to low-temperature and fatigue fracture performance grading of asphalt binders

This thesis focuses on the low-temperature and fatigue cracking of asphalt pavements, tries to gain a better understanding of the failure mechanisms in the asphalt binders, and to work towards an improved asphalt binder specification for low-temperature and fatigue fracture performance grading.; Regular grading according to the American Association of State Highway and Transportation Officials (AASHTO) M320 specification and an extended beam bending rheometry (BBR) tests with grading after different condition times were performed in order to study the effect of physical aging (reversible aging) on asphalt binders. It was found that most binders aged rapidly by showing an increase in creep stiffness and a decrease in creep rate with conditioning time. The binders used for the Lamont, Alberta C-SHRP pavement trial were assessed for their tendency to age at low temperatures and the findings were correlated with the cracking severity after 12 years in service. (Abstract shortened by UMI.)...