Accelerated Testing of Warm Mix Asphalt for Safe and Reliable Freight Transportation

This report presents a new organic warm mix asphalt (WMA) product that has been recently introduced to the U.S. market, which is Polyethylene (PE) Wax-based WMA additive with crystal controller to increase the low temperature cracking resistance and anti-stripping agent to enhance moisture susceptibility. The new PE Wax-based WMA mixtures with recycled asphalt pavement (RAP) materials were also tested using the Hamburg Wheel Tracking (HWT) device and the wheel passes were significantly higher with WMA mixtures with PG 64-28 binder, Minnesota aggregates and 25% RAP than the ones with 64-22 binder, Iowa aggregates and 10% RAP. The HWT test results seemed to be influenced by more on the characteristics of aggregates and RAP materials than the WMA additive. In-service roads in Iowa and Minnesota were successfully rehabilitated using the PE Wax-based WMA mixtures. The average void of 1.5-inch WMA overlay (9.0%) was higher than that of hot mix asphalt (HMA) overlay (7.0%) placed on an urban street in Iowa City. It was partly due to the asphalt temperature that was lowered to match the lower aggregate temperature. As a result, the aggregate temperature for WMA was also significantly lower than HMA. It is interesting to note, however, that the average air void of the cores obtained from the rehabilitation section of the same street using LEADCAP was 6.0%. On Minnesota’s state highway, the average air voids of four WMA and HMA cores for quality control were 5.85% and 5.29%, respectively, and those of four other WMA and HMA cores for quality assurance were 6.05% and 6.01%, respectively. The WMA pavements were easier to reach 94% density with fewer passes of a compactor than HMA. The LEADCAP WMA test section was constructed at the Accelerated Pavement Load Facility (APLF) at Ohio University. The maximum rut measurement was 0.30 and 0.34 inch under each of the loading duel tires. The most significant amount of rut developed after 5,000 repetitions.

  • Supplemental Notes:
    • This research was sponsored by the U.S. Department of Transportation, University Transportation Centers Program.
  • Corporate Authors:

    University of Iowa, Iowa City

    Public Policy Center
    Department of Civil and Environmental Engineering
    Iowa City, IA  United States  52242-1192

    Mid-America Transportation Center

    University of Nebraska-Lincoln
    2200 Vine Street, PO Box 830851
    Lincoln, NE  United States  68583-0851

    Research and Innovative Technology Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • Lee, Hosin
    • Glueckert, Thomas
    • Ahmed, Taha
  • Publication Date: 2012-7


  • English

Media Info

  • Media Type: Digital/other
  • Edition: Final Report
  • Features: Figures; Photos; References; Tables;
  • Pagination: 41p

Subject/Index Terms

Filing Info

  • Accession Number: 01482569
  • Record Type: Publication
  • Report/Paper Numbers: 25-1121-0001-451
  • Created Date: May 24 2013 10:01AM