Material-Specific Effects of Hydrated Lime on the Properties and Performance Behavior of Asphalt Mixtures and Asphaltic Pavements

摘要

This study evaluates hydrated lime-treated hot-mix asphalt (HMA) mixtures through various labor-atory tests, including the dynamic modulus test and performance tests to characterize permanent deformation and fatigue damage resistance both in displacement-controlled and force-controlled modes. Two different asphalt mixtures—the asphalt concrete mixture and the fine aggregate asphalt matrix mixture—which differ only in the amount of additional hydrated lime (0.5–3.0%), are tested. Test results demonstrate material-specific damage characteristics of hydrated lime and the existence of a more appropriate amount of hydrated lime to be added to the HMA mixtures than the current typical application rate such as the addition of 1.0% lime to dry or premoistened aggregates. In ad-dition, the newly released Mechanistic-Empirical Pavement Design Guide (MEPDG) is used for pre-dicting pavement performance related to hydrated lime content. The MEPDG analysis results show that damage prediction models implemented in the current MEPDG are limited to accurately pre-dicting material-specific damage characteristics. Mechanistic models that consider material-specific crack phenomenon and fracture behavior should be pursued.