Project title: Evaluation of binder aging and its influence in aging of hot mix asphalt concrete

Project 0-6009Binder oxidation in pavements and its impact on pavement performance has been addressed bynumerous laboratory studies of binder oxidation chemistry, reaction kinetics, and hardening and its impact onmixture fatigue. Studies also have included some work on binder oxidation and hardening in pavements andthe effectiveness of maintenance treatments. Yet more such studies are needed to better understand thefundamentals of pavement performance as a function of climate and pavement parameters.Based on these reports in the literature, an experimental design has been developed to meet threeobjectives and to provide four products. The objectives are: 1) to develop and calibrate a laboratory test toassess binder aging during the production process and during the field service of the pavement; 2) toincorporate aging for use in a HMA mix design system to produce mixtures that provide adequate resistanceto fatigue cracking, including guidelines to optimize resistance of HMA to aging; and 3) to evaluate the useof maintenance treatments to reduce the aging of asphalt pavements starting at early ages. The products: 1) anew test procedure to characterize binder aging, and predict service life for different applications; 2) anHMA mix design component that incorporates aging and its effect on resistance to fatigue cracking; 3)guidelines for optimizing HMA mixture resistance to aging; and 4) guidelines for the best maintenancetreatments to reduce the aging of binders.The experimental design includes measurements of binder oxidation and hardening at various stagesof binder service, fundamental studies of binder oxidation and hardening kinetics, developing a transportmodel of binder oxidation in pavements, measurements of field oxidation and hardening rates, measurementsof mixture fatigue decline as a function of binder oxidative hardening in both the field and laboratory, andmeasurements of maintenance treatment effectiveness at retarding binder oxidative hardening