Performance Trends in Airport Runway Pavements

Research sponsored by the Federal Aviation Administration (FAA) Office of Airport Safety and Standards (AAS) will extend the expected life of large hub runway pavements from 20 to 40 years. Research is being conducted to collect performance data at major hub airports across the U.S. that will provide performance trends of existing runways and identify factors to be considered in order to extend the pavement life expectance to the goal of 40 years. The purpose of this paper is to briefly describe the research project and to provide preliminary performance trends for 18 runway pavements studied. The pavement condition index (PCI), conducted in accordance with ASTM D5340, is a measure of overall pavement serviceability, and it can be used to track performance over time. It is generally accepted that the PCI decreases at a relatively slow rate over the first years of the pavement life, and then at some point the rate of deterioration increases. Some runways surveyed were relatively new and therefore have no performance history. However, most of the runways studied have been surveyed a number of times and some history of changes in PCI with time are available. The deterioration over time of the runways indicates the effect of maintenance that keeps serviceability at an acceptable level. The distresses found on nearly all runways studied were not load related, which implies that currently the runways are structurally sound and capable of supporting the actual (current) traffic. The predominant distresses observed on the runways studied thus far are: Low to medium severity longitudinal/transverse cracking, low severity weathering, and low severity patching (Asphalt Concrete (AC) pavements); Low to medium spalling, low to medium longitudinal/transverse/diagonal cracking, low severity patching, and pop-outs (Portland Cement Concrete (PCC) pavements). The paper describes the data collection effort and findings thus far.