Hybrid Approach to Characterize Reflective Cracking in Airport Pavements

In airfields, reflective cracking is one of the major distresses in asphalt overlays which are placed on rigid pavements, cracked asphalt pavements, and even in asphalt layers with cement-treated base pavements. Recently, a comprehensive laboratory testing program to characterize reflective cracking was conducted at the Federal Aviation Administration (FAA) NextGen Pavement Materials Laboratory. All tests were conducted on field extracted hot mix asphalt (HMA) cores. Test data from the customized overlay tester (OT) showed an excellent correlation between the Dissipated Energy (DE) and fracture parameters for specimens tested with different maximum crack opening displacement (or displacement rate). Parallel to the laboratory study, a finite element (FE) modeling effort was also carried out. The developed 2D FE model was not only capable of simulating the OT test but also accurately compute the fracture parameters, which consequently can be used to predict the fatigue performance of HMA specimens using empirical equations developed from laboratory testing.