Influence of relative humidity and saturation degree in the mechanical properties of Hot Mix Asphalt (HMA) materials

Understanding the interactions between the environment and the mechanical response of road materials is crucial to achieve more durable pavement structures. This work evaluates, for the first time, the impact of relative humidity (RH) in the linear viscoelastic properties of Hot Mix Asphalt (HMA) materials. A set of specimens were conditioned under specific RH environments, and tested in the new Hollow Cylinder Tester for Asphalt Mixtures (HCT-AM) in order to quantify their dynamic axial modulus and phase angle. The results demonstrate the strong impact of relative humidity on the mechanical properties of the HMA mixture and on its expected field performance.