Combined Use of High RAP Mixtures with Rubber and Polymer Modifications for Maintenance Applications

Abstract: This study investigates the use of high percentage recycled asphalt pavement (RAP) in combination with scrap tire rubber (STR) and ethylene glycidyl acrylate (EGA) terpolymer (commercially Elvaloy) for asphalt pavement maintenance applications. High RAP mixtures were prepared with 40% RAP with STR in the form of crumb rubber (CRW) and devulcanized rubber (DVR), or 40% RAP with Elvaloy polymer. In addition to high RAP asphalt mixtures, full RAP (100% RAP) mixtures using a petroleum-based rejuvenator were also studied to compare the relative mixture performances for the pavement maintenance activities The CRW and DRW mixtures were modified with binders, including approximately 12% rubber content by weight of the binder. All binders were modified using the same PG 58-28 base binder. Dynamic modulus testing for linear viscoelastic characterization, flow number (FN) testing for rutting potential, and indirect tensile strength (ITS) for thermal cracking were conducted to assess the relative performance of the mixes. The results revealed that the environmentally friendly and sustainable 100% RAP and combination mixtures can be used for pothole patching applications.