Initial pavement smoothness has an effect on the future smoothness and life of asphalt concrete (AC) and portland cement concrete (PCC), as well as AC overlays of existing AC and PCC pavements. Initial pavement smoothness has a significant effect in 80 percent of new construction (both AC and PCC pavements) and in 70 percent of AC-overlay construction. Furthermore, using two different analysis techniques, added pavement life can be obtained by achieving higher levels of initial smoothness. Combined results of roughness-model and pavement-failure analyses indicate at least a 9 percent increase in life corresponding to a 25 percent increase in smoothness from target profile index (PI) values of 7 and 5 in./mi (0.11 and 0.08 m/km) for concrete and asphalt pavements, respectively.

The importance of surface texture characteristics to roadway safety was first recognized during the late 1940s and early 1950s when increases in traffic volumes and vehicle speeds resulted in increases in wet-weather crashes and fatalities. As a result, agencies conducted extensive research, including experimental projects around the country, to better understand and improve the surface conditions of portland cement concrete pavement in wet-weather conditions. As new surface-texturing methods were tried and evaluated, pavement engineers recognized that a general trade-off existed between friction and noise; that is, surface textures with higher friction tended to produce greater tire-pavement noise. Although considerable information exists on the influence of surface friction characteristics on safety and tire-pavement noise, it is dispersed among numerous sources. An effort is made to identify and summarize key texture-related information and recommendations based on the current state of the practice. Specifically, pavement texture nomenclature is introduced, methods of measuring and quantifying texture are discussed, traditional and innovative texturing methods and techniques are described, respective conclusions pertaining to the influence of texture characteristics on surface friction and tire-pavement noise are summarized, and current state-of-the-art texture-related recommendations are provided.

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Over the past 4 years, the Oklahoma Department of Transportation (ODOT) has implemented a pavement management system (PMS) to provide the agency with accurate, current, and relevant pavement condition information for use in prioritizing candidate pavement projects based on economic and engineering analyses. Now that the implementation process has been completed, ODOT routinely uses its PMS to enhance network- and project-level decision making. Currently, ODOT contracts with a vendor to collect network-level sensor, geometric, and distress data using automated data collection techniques. The data are then processed with a combination of automated and semiautomated techniques. The agency recognized that the value of the recommendations made by its PMS is greatly dependent on the quality of the collected information included in the PMS. Therefore, ODOT has emphasized the importance of checking the quality of data before they are used for important management decisions. As one way of assessing the data quality, ODOT developed checks of the data collected and submitted by the vendor. ODOT realized the value of creating an automated procedure for checking the final delivered pavement condition database to provide a rapid, repeatable, and accurate assessment of the data quality. To address this need, ODOT developed a visual basic application tool based on Microsoft Access to provide a user-friendly interface to the systematic procedure of conducting the many required data quality checks. In addition to the control and verification site testing procedures and distress ratings checks, this tool will be used by the agency as part of a comprehensive approach to assessing pavement condition data accuracy and completeness. Details regarding the creation and function of the quality assurance tool are provided in this paper.

The development of a prototype performance-related specification (PRS) for concrete pavement construction is summarized. The prototype PRS requires that a pavement lot be divided into consistent sublots for the measurement of quality characteristics, which are then used to estimate future performance and life-cycle costs. The difference between the life-cycle costs of the target (as-designed) pavement and the actual (as-constructed) pavement lot is used to determine a rational pay adjustment. Both means and variations of all quality characteristics are directly considered in the pay factor determination. Extensive laboratory testing was conducted to determine material relationships needed in the prototype PRS. A Windows-based computer program, PaveSpec, was developed for use with the specification in simulation and in generating pay adjustments. However, additional work is required to make this a fully practical PRS.