Use of recycling agents in asphalt mixtures with high recycled materials contents in the United States: A literature review.

Highlights • Summary of current knowledge on recycling agents (rejuvenators) and their application. • Identification of current and future challenges that prevent utilization of recycling agents. • Evaluation of recycling agents effectiveness in binder blends and asphalt mixtures. • Characterization of rejuvenated binder blends and rejuvenated asphalt mixtures. • Cost-effectiveness associated with the use of recycling agents. Abstract Recycling agents, or rejuvenators, are products with chemical and physical characteristics designed to restore the rheological properties of aged asphalt binders to improve the performance of recycled asphalt mixtures with large quantities of reclaimed asphalt pavement (RAP) and recycled asphalt shingles (RAS) that promote economic and environmental benefits. This paper summarizes current knowledge related to the use of recycling agents in the asphalt pavement industry, including properties of recycled and rejuvenated asphalt mixtures. This information is further used to identify current and future challenges that could prevent utilization of recycling agents and production of rejuvenated asphalt mixtures with adequate performance. [ABSTRACT FROM AUTHOR]