Long-Term Pavement Performance: Preliminary Analysis of Constructed Warm-Mix Asphalt Overlay Projects

The Long-Term Pavement Performance (LTPP) program has recently started a new Specific Pavement Study (SPS) experiment to compare the long-term performance of warm mix asphalt (WMA) technologies to conventional hot mix asphalt (HMA). This paper discusses the observations during the construction of the first two test sites, each consisting of a control HMA section and two WMA sections with the foaming and chemical additive technologies. In a preliminary analysis of the collected falling weight deflectometer (FWD) data before and after the overlay construction, the relationship between the mix laydown temperature and the resulting stiffness gain in the pavement structure was investigated. The equivalent pavement elastic modulus was estimated before and after overlay and the change in stiffness was contrasted between the HMA and WMA technologies. No specific trends could be inferred from this preliminary analysis. While the control section has gained more stiffness as a result of the HMA overlay compared to the other WMA overlays in one site, the chemical WMA section is demonstrating the highest gain in stiffness in the other site. Among the WMA sections, the average amount of added stiffness was higher for the foaming process in one site and for the chemical additive in the other. This suggests that the observed differences in the stiffness are predominantly a result of construction variability and cannot be attributed to the differences in mix and laydown temperatures. As performance monitoring and materials sampling and testing continues with time, further details might emerge regarding the long-term performance of warm mix technologies compared to each other and to the conventional hot mix.

  • Supplemental Notes:
    • This paper was sponsored by TRB committee AFD80 Standing Committee on Strength and Deformation Characteristics of Pavement Sections. Alternate title: Long-Term Pavement Performance: A Preliminary Analysis of the Constructed Warm Mix Asphalt Overlay Projects.
  • Corporate Authors:

    Transportation Research Board

    500 Fifth Street, NW
    Washington, DC  United States  20001
  • Authors:
    • Rahman, Md Tahmidur
    • Burchett, Thomas J
    • Kargah-Ostadi, Nima
    • Sassin, James M
  • Conference:
  • Date: 2016

Language

  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; References; Tables;
  • Pagination: 13p
  • Monograph Title: TRB 95th Annual Meeting Compendium of Papers

Subject/Index Terms

Filing Info

  • Accession Number: 01592502
  • Record Type: Publication
  • Report/Paper Numbers: 16-5768
  • Files: PRP, TRIS, TRB, ATRI
  • Created Date: Feb 29 2016 5:49PM