Pay Factors for Asphalt-Concrete Construction: Effect of Construction Quality on Agency Costs

The quality of the construction process is a major factor in determining how well a pavement will perform under traffic loading and when subjected to environmental influences. To improve the construction process, quality control/quality assurance (QC/QA) procedures and pay incentives have been instituted in recent years. It is the objective of this report to demonstrate a rational and feasible method for quantitatively establishing penalties/bonuses for asphalt concrete construction with the initial emphasis placed on new asphalt concrete pavement construction. The approach makes use of performance models for asphalt concrete used to interpret the. results of the CAL/APT program (1) and WesTrack (2). The performance model for fatigue resulted from the CAL/APT program while the one for rutting came from the WesTrack accelerated pavement test program. For both modes of distress the system considers the means and variances of asphalt content, air-void content, asphalt-concrete thickness, and aggregate gradation. In estimating damage under traffic loading, the pavement is treated as a multilayer, elastic system. The performance models compute the distribution of pavement life, expressed as ESALs, using Monte Carlo simulation techniques. Costs are established using a cost model which considers only the time to the next rehabilitation activity. It understates agency costs by ignoring possible effects of construction quality on future rehabilitation costs: it ignores future rehabilitation activity beyond the first cycle. It requires an exogenous estimate of future rehabilitation costs, traffic growth, expected years of new-pavement life, and a discount rate representing the time value of money. The development of single sets of pay factors including both fatigue and rutting reflects the following. The recommended bonus for superior work is the smaller of that for either fatigue or rutting. For asphalt content, there are no bonuses for “dry” mixes. While such mixes may be rut resistant, they may lead to early fatigue distress. The penalty for larger-than-target asphalt content is determined by reduction in rutting resistance caused by surplus asphalt. For asphalt-concrete thickness, the recommended pay factors are based only on fatigue performance while for aggregate gradation, the recommended pay factors are based primarily on rutting. For air-void content, the recommended pay factors reflect both fatigue and rutting considerations.

  • Record URL:
  • Corporate Authors:

    California Department of Transportation

    1120 N Street
    Sacramento, CA  United States  95814

    University of California, Berkeley

    Institute of Transportation Studies, Pavement Research Center
    1353 South 46th Street
    Richmond, CA  United States  94804
  • Authors:
    • Deacon, John A
    • Monismith, Carl L
    • Harvey, John T
    • Popescu, Lorina
  • Publication Date: 2001-2-1

Language

  • English

Media Info

  • Media Type: Digital/other
  • Features: Appendices; Figures; References; Tables;
  • Pagination: 106p

Subject/Index Terms

Filing Info

  • Accession Number: 01768848
  • Record Type: Publication
  • Source Agency: UC Berkeley Transportation Library
  • Report/Paper Numbers: TM-UCB-PRC-2001-1
  • Files: CALTRANS, BTRIS, TRIS, ATRI, STATEDOT
  • Created Date: Nov 10 2020 5:24PM