Investigation of Temperature Dependency of Asphalt Concrete Using Laboratory Dynamic Modulus and Field Deflection Testing

The investigation of temperature dependency of asphalt mixtures and pavements has several applications in pavement engineering. To estimate the modulus of asphalt pavement layers from field deflection tests such as Falling Weight Deflectometer (FWD), it is necessary to adjust the deflection or backcalculated modulus to a reference temperature. Additionally, in field studies, pavement responses like stresses and strains are measured at various pavement temperatures. To quantify the impact of variables such as load, it is necessary to convert pavement responses to a reference temperature. In this study, 35 asphalt mixtures were analyzed to investigate the variation of their laboratory dynamic moduli with testing temperatures. An exponential model was proposed for the temperature dependency of the dynamic moduli of asphalt mixtures. A temperature correction model was also developed as a function of testing temperatures and material properties. Additionally, thirteen temperature correction factor models for FWD testing were reviewed. Variations in the estimation of temperature correction factors between models were observed. As, based on dynamic modulus testing, the temperature correction model was a function of testing temperature and material properties, it is expected to provide a better estimation of temperature dependency for asphalt pavements.