The compaction characteristics of the unbound material underlying the flexible pavement have been found to be critical to the performance of the pavement structure. This is especially so for airport pavements subjected toheavy aircraft loads. From previous tests at the National Airport Pavement Test Facility (NAPTF), it was found that the subbase experienced excessive compaction during trafficking. This study focused on studying the compaction characteristics of the subbase material using the Superpave GyratoryCompactor (SGC) and correlating the measured performance with field performance data. Since the SGC has not been widely used for studying the performance of unbound material, the compaction characteristics in the Superpave Gyratory Test were calibrated to field compaction of the subbase material during construction at similar moisture contents. The field data collected includes density measurements with each pass of the roller during compaction and the deflection of the pavement structure during aircraft trafficking. This is correlated with the data from the SGC including changes indensity with additional energy input and it was found that the SGC can beused as a suitable predictor of compaction characteristics of unbound material. This paper provides the airport pavement designers the efficacy of using the SGC as a means of evaluating the performance of unbound materialduring construction and trafficking.
Abstract