The determination of the flexural creep stiffness of asphalt binder using bending beam rheometer

Abstract

Rutting, fatigue cracking, and thermal cracking are the major types of distresses in asphalt pavement. These distresses are highly affected by the characteristics of asphalt binder (asphalt+additive). Binder properties play a key role in controlling low temperature cracking. The major objective of this paper is to determine the flexural creep stiffness of asphalt binder at lower temperature. AC-10 grade and AC-20 grade of asphalt cement were employed. Pyrolyzed carbon black (CBp) from scrap tires and commercial carbon black (CB) are used as an additive. The inclusion of CBp and CB increases the flexural creep stiffness of asphalt binder. Considering the recommendation of SHRP, all the testing resusts except AC-20 with 20% CB were within the limit value, maximum 300MPa at 60 second for BBR test. The flexural creep stiffness at lower temperature (less than 0°C) shows a linear relationship in log-log scale as the loading time increases. The flexural creep stiffness of asphalt binder depends on the type of asphalt cement and additive, testing temperature, as well as loading time.