Considering a New Sample Unit Definition for Pavement Condition Index

One of the main components of pavement management system (PMS) is pavement evaluation. Several indices have been defined for the evaluation of existing pavement. The Pavement Condition Index (PCI) is a common index used for pavement evaluation. In order to calculate PCI, a significant volume of condition data -based on distress surveying- is required. The objective of this research is to reduce the volume of required data by introducing a new sample unit definition. For this reason, “wheel path sample units” were defined and used instead of the standard sample unit (according to ASTM D6433). The analysis of results showed that not only there is no significant difference between standard and wheel path PCIs, but also there is a good correlation between standard PCI and both wheel path PCI (PCIw) and outside wheel path PCI (PCIow), corresponding to R2 = 0.929 and R2 = 0.874, respectively. Also, PCIow saves a great amount of time and energy.