Effects of Rejuvenating Agents on Superpave Mixtures Containing Reclaimed Asphalt Pavement

TLDR

Rejuvenators are rarely employed as softening agents in recycled asphalt pavement (RAP) recycling. This study designed Superpave mixtures with RAP using a rejuvenator and a softer binder, then assessed their volumetric properties, indirect tensile strength, and rutting resistance with an asphalt pavement analyzer. The rejuvenator dosage was set according to RAP binder blending charts, and twelve Superpave mixtures—ten with RAP and two virgin—were formulated. Mixtures with the rejuvenator exhibited superior ITS and rutting performance, allowed 10 % more RAP inclusion, and confirmed that Superpave binder blending charts can guide rejuvenator content.

Abstract

Rejuvenator is not a commonly used softening agent to be used in recycling of reclaimed asphalt pavement (RAP). In this study, Superpave mixtures containing RAP were designed using rejuvenating agents, including a rejuvenator and a softer binder, and subsequently evaluated in terms of the volumetric results, obtained the indirect tensile strength (ITS) of samples as well as evaluating the mixtures for rutting using the asphalt pavement analyzer (APA). The content of the rejuvenator used for those mixtures containing the rejuvenator was determined from the blending charts of RAP binders containing the rejuvenator. A total of 12 Superpave mixtures including 10 containing RAP and two virgin were designed. The results indicated, for the mixtures tested for this project, that: (1) properties of the recycled mixtures using the rejuvenator, such as ITS and APA, were better than those containing the softer binder; (2) 10% more RAP could be incorporated in the Superpave mixtures by using the rejuvenator than using the softer binder; and (3) the blending charts established under the Superpave binder specifications can be used to determine the content of the rejuvenator for the recycling.