Evaluate the Use of Percent Within Limits as Payment Adjustment Factor for Placement of Asphalt Mixes

The current payment adjustment factors for asphalt mixes used by TxDOT awards bonuses to the contractors based on the average of the in-place voids. This practice can potentially create a scenario where the contractors can deliver inconsistent quality but still receive a bonus because of the average performance. This project will evaluate the use of percent within limits (PWL) that incorporates variability as the payment adjustment factor for asphalt mixes. The researcher team will assess the practices for PWL adopted by other states and then compile data from various Receiving Agency databases (SiteManager, DCIS, and PMIS) to assess the overall relationship between payment adjustment factors and performance of pavements and cost of maintenance. The researcher team will develop at least two alternative models. Finally, the researcher team will use the existing data with the proposed alternatives to identify the cost benefit to the agency using each model as well as trends in terms of contractors or conditions that can contribute to poor performance and/or higher variability based on the new alternatives. After synthesizing the results in an implementation-friendly format, the researcher team will provide a detailed analysis to help TxDOT justify transition to the new proposed system.


  • English


  • Status: Completed
  • Funding: $179194
  • Contract Numbers:


  • Sponsor Organizations:

    Texas Department of Transportation

    125 E. 11th Street
    Austin, TX  United States  78701-2483
  • Project Managers:

    Jensen, Darrin

  • Performing Organizations:

    Center for Transportation Research

    University of Texas at Austin
    1616 Guadalupe, Suite 4.202
    Austin, TX  United States  78701
  • Principal Investigators:

    Bhasin, Amit

  • Start Date: 20170901
  • Expected Completion Date: 20190831
  • Actual Completion Date: 20190831

Subject/Index Terms

Filing Info

  • Accession Number: 01648634
  • Record Type: Research project
  • Source Agency: Texas Department of Transportation
  • Contract Numbers: 0-6967
  • Files: RiP, STATEDOT
  • Created Date: Oct 20 2017 12:28PM