Refinement and Field Validation of Mix Design Criteria for 4.75 mm Superpave Mixes

Within the Superpave mix design system there are design criteria for 9.5 to 37.5 mm nominal maximum aggregate size (NMAS) mixes. Many agencies have expressed an interest in using a 4.75 mm NMAS mix because such a mix could result in an easy riding surface, be used for thin lift applications, correct surface defects (leveling), decrease construction time, provide a use for manufactured screening stockpiles, provide a very economical surface mix for low traffic volume facilities, and be used for thin lift maintenance. In February 2002, the National Center for Asphalt Technology completed a study to develop Superpave mix design criteria for a 4.75 mm NMAS mix (Cooley et al, 2002). NCAT's research was used, in part, by the Superpave Mixture/Aggregate Expert Task Group to recommend to AASHTO the addition of 4.75 mm NMAS mixes to the Superpave mix design system. The objective objective of this study will be to refine and field validate design criteria for 4.75 mm NMAS Superpave mixes. Additionally, guidelines for the production, construction, and use of this mix type will be developed.

  • Supplemental Notes:
    • Pooled Fund study partners include Departments of Transportation from the following states: AL, CT, FL, MN, MO, NH, VA, and WI.


  • English


  • Status: Completed
  • Funding: $240000.00
  • Contract Numbers:


  • Sponsor Organizations:

    Alabama Department of Transportation

    1409 Coliseum Boulevard
    Montgomery, AL  United States  36130-3050
  • Project Managers:

    Harris, Ivy

  • Start Date: 20040118
  • Expected Completion Date: 0
  • Actual Completion Date: 20090630
  • Source Data: RiP Project 19887

Subject/Index Terms

Filing Info

  • Accession Number: 01462440
  • Record Type: Research project
  • Source Agency: Alabama Department of Transportation
  • Contract Numbers: TPF-5(17)
  • Files: RIP, STATEDOT
  • Created Date: Jan 3 2013 2:03PM