Evaluation of Revised Incentive-Only Ride Specification for Asphalt Pavements

016750932018FINAL REPORTPerforming Organization Report No.: VTRC 18-R11PDFTech ReportFHWA/VTRC 18-R11107486SmoothnessAsphalt pavementsBefore and after studiesEvaluation and assessmentIncentivesPavingQuality controlSpecificationsRoughnessRide specificationIRIincentive-only specificationsmoothness specificationVirginiaUnited StatesVirginia Transportation Research CouncilNair, HarikrishnanMcGhee, Kevin KHabib, AffanWells, MichaelSaha, BipadVirginia Transportation Research CouncilVirginia. Dept. of TransportationUnited States. Federal Highway AdministrationNTL-HIGHWAY/ROAD TRANSPORTATION-Pavement Management and PerformanceUS Transportation CollectionIn late 2011, the executive leadership of the Virginia Department of Transportation (VDOT) formed an Asphalt Quality Task Force to identify and recommend specific achievable measures to improve the quality of asphalt paving in Virginia. The task force recommended that VDOT assess the feasibility of making an incentive-only provision for ride quality the default for projects that do not qualify for VDOT\u2019s regular specification for rideability, which includes both incentives and disincentives. A pilot application of the incentive-only provision was conducted during VDOT\u2019s 2013 construction season. Although the results indicated no statistically reliable distinction in ride quality between the projects under the incentive-only provision and those with no rideability requirement, the number of sites, VDOT districts, contractors, etc., included in the assessment was limited. The research summarized through this study addressed a concern that the criteria for the ride specification in the original (2013) incentive-only provision may have failed to reflect quality adequately beyond a limited 52.8 ft (0.01-mi) base length. The study documented the application of an incentive-only provision to a wider range of projects during VDOT\u2019s 2015 construction season. The revised criteria addressed some of the concerns associated with the original criteria. The revised provision maintains the potential for incentives while reducing the likelihood for \u201caccidental\u201d bonuses when the final ride quality is marginal on average but highly variable. Overall, there remains little statistically reliable distinction between the achieved ride quality of projects under the incentive-only provision and of general resurfacing projects with no ride quality requirement. However, based on before and after determinations of the International Roughness Index, greater improvements in ride quality were achieved with the incentive-only pilots (at least in some cases) as compared to sites under no ride quality requirement. The revised incentive-only provision provides a mechanism through which a contractor has an opportunity to recover costs associated with improved practices and perhaps even earn incentives based on good ride quality. It does this while reducing the risk that VDOT will be subject to incentives for otherwise marginal quality work