The Port Authority of New York and New Jersey (PANYNJ) owns and operates two of the most heavily used airports in the United States. Newark Liberty International Airport (Newark) in New Jersey and John F. Kennedy International Airport (JFK) in New York handle approximately 1 million arrivals and departures each year. Although their runways witness an extreme amount of loading, the primary distress observed on them is top-down fatigue cracking with little to no rutting. Recently, the PANYNJ observed premature top-down fatigue cracking at two runways at Newark. After an evaluation of several runways at JFK and Newark, it was discovered that asphalt mixtures of similar design were resulting in varying levels of fatigue cracking performance. For a better understanding of the fatigue cracking performance of asphalt mixtures placed on airport runways in the New York and New Jersey area, a forensic study was conducted on field cores recovered from five runways maintained by PANYNJ. Asphalt binder was recovered and tested from the field cores at different depths from the pavement surface. The test results of the study showed that the Δ Tcr parameter, measured with the critical low-temperature results from a bending beam rheometer, could be used within a purchase specification to help mitigate the potential receipt of asphalt binders prone to accelerated aging and cracking. Meanwhile, the overlay tester and the semicircular bending flexibility index were found to be capable of potential implementation as quality control tests to ensure that asphalt mixtures produced for asphalt airfields in the New York and New Jersey area were not susceptible to top-down fatigue cracking.
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