Validating an Endurance Limit for HMA Pavements: Laboratory Experiment and Algorithm Development

Implementation of a fully characterized endurance limit in the mechanistic-empirical pavement design guide (MEPDG) software will enhance the ability to prepare long-life hot mix asphalt (HMA) pavement designs that achieve a balance between practical layer thickness and satisfactory fatigue performance. National Cooperative Highway Research Project NCHRP) Project 9-44 prepared a multi-part work plan to (1) validate, through an analysis of laboratory and field data, the existence of an endurance limit for HMA pavements characterized in NCHRP Project 9-38; (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 the MEPDG and other approaches to HMA mechanistic-empirical pavement design. Based on the results of a workshop with the participation of U.S. and international experts in HMA fatigue cracking, the 9-44 contractor has proposed the incorporation of a variable endurance limit that is likely a function of mixture composition, binder properties, temperature, aging, and duration of rest periods in HMA pavement analysis through the modification of current fatigue relationships in the MEPDG. Thus, the work plan includes a laboratory experiment to quantify the effect of these variables on the rate of damage and damage recovery. The research plan further proposes the use of accelerated pavement testing (APT) to validate certain effects in the high-strain region of the fatigue curve; however, the overall field validation effort is focused on the evaluation of full-scale test roads and in-service pavement sections. The analysis of in-service pavements requires their detailed composition and construction history and the ability to make and document assumptions where such firm data do not exist. This situation argues for an in-depth analysis of a small number of well-documented pavements. Research is needed to (1) carry out the laboratory portion of the research plan developed in NCHRP Project 9-44 within the bounds described in the tasks below and (2) produce an algorithm to implement a fatigue endurance limit in the MEPDG and other selected design methods. A future Project 9-44B is anticipated to conduct field validation of the endurance limit algorithm and further revise the algorithm as determined by the results of the field validation. The objectives of this research are to (1) carry out a laboratory experiment to identify the mixture and pavement layer design features related to an endurance limit for bottom-initiated fatigue cracking of HMA and (2) develop an algorithm to incorporate this endurance limit into the MEPDG and other selected pavement design methods.


  • English


  • Status: Completed
  • Contract Numbers:

    Project 9-44A

  • 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:

    Arizona State University, Tempe

    Tempe, AZ  United States 
  • Principal Investigators:

    Mamiouk, Michael

  • Start Date: 20090901
  • Expected Completion Date: 0
  • Actual Completion Date: 20130930
  • Source Data: RiP Project 17995

Subject/Index Terms

Filing Info

  • Accession Number: 01464472
  • Record Type: Research project
  • Source Agency: National Cooperative Highway Research Program
  • Contract Numbers: Project 9-44A
  • Files: TRB, RiP, USDOT
  • Created Date: Jan 3 2013 2:43PM