Laboratory Evaluation of Foamed Asphalt Mixtures Containing 100% RAP and Rejuvenator: Georgia's Experience

A research project on cold asphalt recycling with foamed asphalt was recently completed using 100% Reclaimed Asphalt Pavement (RAP) containing rejuvenator in the state of Georgia. The research aimed to see the impact of rejuvenator on 100% RAP foamed asphalt mixtures and assess the feasibility of using the mix as a base layer. This paper presents a part of the research findings, specifically focusing on the performance of 100% RAP foamed asphalt mixtures with and without rejuvenator through three laboratory tests: Marshall Stability (MS), Indirect Tensile Strength (ITS), and Semi-Circular Bending (SCB). Three rejuvenator dosage levels (6%, 12%, and 18%) were pre-determined based on asphalt viscosity (G*/sin δ) of extracted RAP asphalt. The test results indicate that the MS and ITS of the mixtures without rejuvenator are reasonably high enough to be used as a base layer. However, when a 6% or more rejuvenator is dosed in the mixtures, the MS and ITS significantly decrease. The fracture resistance at an intermediate temperature measured by the SCB tests indicates that the mixtures without rejuvenator are more brittle than conventional Hot Mix Asphalt (HMA). When a 6% or more rejuvenator is added, the Flexibility Index (FI) shows that the mixtures become more crack-resistible than both HMA and no-rejuvenator 100% RAP foamed asphalt mixtures. It is concluded that the impact of rejuvenator on the structural integrity of the 100% RAP foamed asphalt mixtures is significant; it helps increase the cracking resistance, but considerably decreases the stability and indirect strength.

  • Supplemental Notes:
    • This paper was sponsored by TRB committee AFK30 Standing Committee on Non-Binder Components of Asphalt Mixtures.
  • Corporate Authors:

    Transportation Research Board

    ,    
  • Authors:
    • Kim, Sungun
    • Jeong, M Myung
    • Shen, Junan
  • Conference:
  • Date: 2019

Language

  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; References; Tables;
  • Pagination: 6p

Subject/Index Terms

Filing Info

  • Accession Number: 01698412
  • Record Type: Publication
  • Report/Paper Numbers: 19-05221
  • Files: TRIS, TRB, ATRI
  • Created Date: Dec 7 2018 9:38AM