Developing a Plan for Validating an Endurance Limit for HMA Pavements

Bottom-up fatigue cracking occurs when traffic loads result in tensile strains of a magnitude sufficient to initiate cracking that eventually propagates through the hot mix asphalt (HMA) layers. Identifying the design parameters that preclude the initiation and propagation of fatigue cracks will result in long-life pavement designs that are not overly conservative. The strain level in an asphalt layer below which fatigue damage does not occur, known as the endurance limit, has not been established for HMA pavements. The current state of pavement design does not recognize endurance limits for HMA pavements. Both the 1993 AASHTO pavement design guide and the Mechanistic-Empirical Pavement Design Guide (developed in NCHRP project 1-37A) yield pavement designs in which the pavement thickness increases as design traffic increases. Research to establish the existence of an endurance limit for HMA mixes was completed in NCHRP Project 9-38, Endurance Limit of Hot Mix Asphalt Mixtures to Prevent Fatigue Cracking in Flexible Pavements. The experimental plan developed here will be implemented in NCHRP Project 9-44A. The objectives of this study are to prepare plans to (1) validate the existence of an endurance limit for HMA mixes in pavements through an analysis of laboratory and field data; (2) determine, insofar as possible, the shift factor between the endurance limits for HMA mixes measured in the laboratory and the field; and (3) identify and recommend methodologies for incorporating an endurance limit in HMA mechanistic-empirical pavement design. The plan shall make use of materials and performance data from appropriate U.S. and worldwide field and accelerated pavement test programs. Within the context of this research, a methodology shall entail a test protocol, algorithms characterizing fatigue damage, and the incorporation of the test protocol and algorithms in a mechanistic-empirical (M-E) pavement design method. This research must be coordinated with that under way in NCHRP Projects 1-41, Models for Predicting Reflection Cracking of Hot-Mix Asphalt Overlays, and 1-42A, Models for Predicting Top-Down Cracking of Hot-Mix Asphalt Layers.


  • English


  • Status: Completed
  • Funding: $250000.00
  • Contract Numbers:

    Project 9-44

  • Sponsor Organizations:

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590

    American Association of State Highway and Transportation Officials (AASHTO)

    444 North Capitol Street, NW
    Washington, DC  United States  20001

    National Cooperative Highway Research Program

    Transportation Research Board
    500 Fifth Street, NW
    Washington, DC  United States  20001
  • Project Managers:

    Harrigan, Edward

  • Performing Organizations:

    Advanced Asphalt Technologies, LLC

    108 Powers Court, Suite 100
    Sterling, VA  United States  20166-9321
  • Principal Investigators:

    Bonaquist, Ramon

  • Start Date: 20070417
  • Expected Completion Date: 0
  • Actual Completion Date: 20090228
  • Source Data: RiP Project 11819

Subject/Index Terms

Filing Info

  • Accession Number: 01462935
  • Record Type: Research project
  • Source Agency: National Cooperative Highway Research Program
  • Contract Numbers: Project 9-44
  • Files: RIP, USDOT
  • Created Date: Jan 3 2013 2:13PM