Asphalt Mix Rejuvenators Synthesis

2020PDFTech ReportBlanchette, AndreaLee, Sheue TorngWood, TomWSBNational Road Research AllianceMinnesota. Department of TransportationMinnesota. Department of TransportationMinnesotaUnited StatesCaliforniaIllinoisIowaMichiganNorth DakotaWisconsinAdditivesAsphalt concrete pavementsLiterature reviewsReclaimed asphalt pavementsRecycled materialsShinglesState of the practiceSurveysAsphalt additivesAsphalt mixturesBindersBlendingNRRA202002(C)1033924Final ReportIn recent years, the asphalt industry has seen an increase in using reclaimed asphalt pavements (RAP) and recycled asphalt shingles (RAS) in new asphalt concrete pavements. Rejuvenating additives are incorporated into asphalt mixes to neutralize the effects of using higher percentages of RAP and RAS in new asphalt concrete pavements. The implementation of incorporating rejuvenating agents in high-RAP or RAS asphalt mixes has led to the evaluation of their capability to restore the properties of aged binder to a condition that is similar to virgin asphalt binders. There are two major types of rejuvenators used: petroleum-based rejuvenators and bio-based rejuvenators. The purpose of this project is to compile a synthesis of current practices being used by the states and industries in the area of mix rejuvenators. This synthesis provides the state of practice in the National Road Research Alliance (NRRA) member states and will be used as guidance for the NRRA\u2019s Asphalt Mix Rejuvenator Field Section research that was in the contracting stage as of March 2020. This synthesis includes a summary of experiences from various agencies and industries on the use of asphalt mix rejuvenators. A literature review was performed and includes but is not limited to the type of rejuvenators used, dosage rate, method of blending the rejuvenators with the RAP and/or RAS, percentage of RAP and/or RAS used, and type of testing conducted to evaluate the effectiveness of a rejuvenator.104