Book Description

Evaluation of pavement condition is the principle source of information for the effective management of the road network for local and state transportation agencies. However, transportation agencies in the United States are using different pavement rating systems to evaluate their pavement condition. The data collection system, measurement units, and calculation techniques have been modified and updated by several states to incorporate new technological development with time. Several transportation agencies are willing to update their old pavement rating systems while others elected to gradually switch to more accurate rating systems. This study focuses on the potential enhancements on the Pavement Rating Index (PRI) used by Nevada Department of Transportation (NDOT) to make it more consistent with nationally applied systems such as the Pavement Condition Index (PCI) developed by U.S. Army Construction Engineering Research Laboratory. Pavement condition data that were utilized to calculate PRI over the last 15 years were converted into PCI compatible format using a suitable conversion technique. Estimated PCI values were plotted against the corresponding PRI value showed moderate correlation with R2 value of 0.56. The current PRI system was then enhanced to eliminate some of its deficiencies. The statistical relationship between the enhanced PRI and PCI showed improved correlation with R2 value of 0.75. The study concluded that a successful correlation between the PRI system and the PCI system can be achieved in Nevada while maintaining the use of the historical pavement condition data. This study also suggests using a recommended PRIr system which adds the impact of roughness and friction onto the enhanced PRI system. Finally, this study compares the road maintenance strategies suggested by the current PRI system and the PRIr system with the time based schedule and the actual activities applied on the pavement section. This comparison concluded that, while both the PRI and PRIr systems show good correlations with the time based schedule and actual activities for assigning preventive and corrective maintenance strategies, the PRIr system showed improved correlations with the time based schedule and actual activities for assigning the overlay strategy. The PRIr system is recommended for implementation by NDOT due to its consistency with national systems (i.e., PCI) and its superior correlations with time based schedule and actual activities for overlays which leads to significant savings of rehabilitation funds.