Analysis of airfield composite pavement responses using full-scale accelerated pavement testing and finite element method

This study focuses on the critical responses of airfield composite pavements that are composed of hot-mix asphalt (HMA) overlay and Portland cement concrete (PCC) pavement. Accelerated pavement testing (APT) and a finite element (FE) method were employed to investigate the effects of three influential factors: temperature, interface bonding, and load level. A full-scale test field was constructed for this study and instrumented with 20 strain gauges and 32 temperature sensors. A finite element model was developed based on the parameters derived from laboratory and field tests and the model was then validated through measurements. The results indicate that longitudinal strain is more critical than transverse strain in an HMA overlay when subjected to moving loads. Moreover, the results underscore that temperature significantly affects the responses of HMA overlays and that the relationship between temperature and pavement responses is sigmoidal. Furthermore, a good interface bonding is able to significantly reduce the critical strain in an HMA overlay and the interface bonding strength is very sensitive to the amount of tack coat. The positive strain near to the surface of HMA overlay is due to high compressive stress, which is different from the tensile strain used in fatigue testing. (C) 2019 Elsevier Ltd. All rights reserved.