Characterising the long-term rejuvenating effectiveness of recycling agents on asphalt blends and mixtures with high RAP and RAS contents Conference Paper uri icon

abstract

  • 2017 Association of Asphalt Paving Technologist. All rights reserved. Although the use of high reclaimed asphalt pavement (RAP) and recycled asphalt shingles (RAS) contents in asphalt mixtures is desirable for environmental and economic reasons, these mixtures are prone to cracking raveling and other durability-related pavement distresses mainly due to the heavily aged recycled binders. Highway agencies and the asphalt paving Industry have been exploring the use of recycling agents (RA) In order to produce these mixtures with desirable performance. This study focused on characterizing the long-Term rejuvenating effectiveness ofRAon asphalt blends and mixtures with high RAP and RAS contents. Materials from two field projects were used to prepare a number of asphalt blends and mixtures with various combinations of base binder, recycled material, and RA These blends and mixtures were subject to various aging protocols prior to being characterized for their oxidation kinetics, rheological properties, and cracking resistance. The test results Indicated that the RA evaluated in this study were effective in partially restoring the properties of recycled materials, but their rejuvenating effectiveness diminished with aging. Nevertheless, the recycled blends and mixtures with RA achieved equivalent or even better rheological properties and cracking resistance than those with an allowable amount of recycled materials per agency specifications but without RA. In addition, adding RA had no significant effect on the oxidation kinetics of the recycled blends, but increased their susceptibility to physical hardening in response to oxidation. Finally, the correlation between laboratory aging protocols for asphalt blends and mixtures were determined; the laboratory long-Term oven aging protocols of five days at 85C on compacted specimens and one day at 13iC on loose mix yielded binders with equivalent rheological properties to those subjected to rolling thin film oven (RTFO) pita approximately ten and 40 hours of pressure aging vessel (PA V), respectively.

published proceedings

  • ROAD MATERIALS AND PAVEMENT DESIGN

author list (cited authors)

  • Yin, F., Kaseer, F., Arambula-Mercado, E., & Martin, A. E.

citation count

  • 65

complete list of authors

  • Yin, Fan||Kaseer, Fawaz||Arambula-Mercado, Edith||Martin, Amy Epps

publication date

  • November 2017