Short-Term Aging of Loose Asphalt Mixtures vs. Long-Term Aging of Compact Asphalt Mixtures: An Equivalence

Understanding the effects of aging in asphalt binders and how the virgin binder is replaced with the aged material is important for controlling the low-temperature cracking behavior of pavements. Any test used on asphalt mixtures must be able to capture the addition of Reclaimed Asphalt Pavement (RAP) and progressive long-term aging. In this study, asphalt mixtures made from two mix designs, four different RAP contents, and six different aging periods at two different temperatures were analyzed. Results show the potential of the Bending Beam Rheometer (BBR) to be able to detect changes in mixture properties. Furthermore, the applicability of AASHTO TP125-16 in the field was strengthened by finding loose-mixture-aging method (at 135°C) as a more convenient way of aging asphalt mixtures than the compacted-mixture-aging (at 80°C). RAP and Aging indices were introduced based on the ‘control mixture’ properties to find an equivalence between the two aging methods. It was found that one hour of loose-mixture-aging at 135°C is equivalent to 30 hours of compacted-mixture-aging at 80°C for a virgin mixture with no RAP. Additionally, for asphalt concrete with 35% RAP, this equivalent time is 55 hours. Results indicate that virgin binder has a higher rate of ‘stiffness’ gain than the blended binder from RAP and virgin binders. This study adds to the benefits of BBR as a potential quality control tool for low-temperature performance during construction.

  • Supplemental Notes:
    • This paper was sponsored by TRB committee AFK10 Standing Committee on Critical Issues and Emerging Technologies in Asphalt. Alternate title: An Equivalence Between Methods of Aging for Determining the Low-Temperature Performance of Asphalt Mixtures.
  • Corporate Authors:

    Transportation Research Board

    ,    
  • Authors:
    • Asib, Abu Sufian Mohammad
    • Romero, Pedro
    • Safazadeh, Faramarz
  • Conference:
  • Date: 2019

Language

  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; References;
  • Pagination: 7p

Subject/Index Terms

Filing Info

  • Accession Number: 01698421
  • Record Type: Publication
  • Report/Paper Numbers: 19-01750
  • Files: TRIS, TRB, ATRI
  • Created Date: Dec 7 2018 9:49AM