Evaluating the Use of Traffic-Speed-Deflectometer-Based Pavement Structural Data in Virginia Department of Transportation’s Pavement Management Processes for Flexible Pavements

Incorporating the structural condition of pavements into the maintenance and rehabilitation treatment selection process is essential for improving performance and prolonging service life. However, because of challenges in network-level structural condition testing, agencies often rely solely on surface-based condition data. This paper proposes and evaluates an approach to incorporate structural condition information from a traffic speed deflectometer into the pavement management decisions of the Virginia Department of Transportation in the U.S. The approach follows the AASHTO design procedure to calculate the effective structural number (SN eff ) and uses SN eff to determine the remaining structural life (RSTL). Analysis of 4,250 lane-miles of interstate and primary roads revealed that, while 90%, 80%, and 30% of primary roads had an RSTL of at least 5, 10, and 20 years, respectively, interstate roads were in better condition, with 91%, 88%, and 82% having an RSTL of at least 5, 10, and 20 years, respectively. A structural condition indicator based on RSTL thresholds for selecting treatment categories was proposed. Final treatment recommendations were derived by combining the current surface-distress-based categories with the proposed structural-condition-based categories. Unconstrained needs analysis, including detailed case studies, showed differences in needs when structural condition was considered, compared with using only surface-based condition information. These differences in needs varied with the existing pavement condition. While the proposed RSTL approach can enhance treatment selection, a systematic investigation is recommended to determine appropriate intervals between structural testing cycles at the network level.