The Effectiveness of Using the Overlay Tester Setup to Evaluate the Performance of Asphalt Mixtures against Reflective Cracking

Reflective cracking is common distress when hot-mix asphalt (HMA) overlays are constructed on top of a pre-cracked base. Cracks on existing base gradually propagate upward because of traffic loading and/or temperature variation, reach surface course, and result in reflective cracking. Previous studies demonstrated that Texas Transportation Institute overlay tester (OT) could effectively simulate the effect of temperature variation, which is considered as the leading mechanism causing reflective cracking in the field. In this study, the effectiveness of using the OT test setup to mimic the field and evaluate the performance of various HMAs against reflective cracking is assessed based on various aspects found in the literature. It was concluded that OT is the most suitable equipment to study thermally induced reflective cracking in the laboratory. Additionally, potential modifications to improve the OT setup is proposed, which is expected to provide a more representative performance evaluation of mixtures against reflective cracking.