Mechanical 3D characterization of epoxy asphalt concrete for pavement layers of orthotropic steel decks

• We measured E∗ and ν∗ν∗ of epoxy asphalt concrete (EAC) and hot mix asphalt (HMA).
• EAC was stiffer than HMA at all reduced frequencies. The TTSP was not valid for EAC.
• For EAC, ν0ν0 ranged from 0.27 to 0.45; ϕvϕv was lower than 5°.
• For HMA the master curve of ν0ν0 showed a maximum.

Epoxy asphalt has been used for over 40 years to pave orthotropic steel deck bridges. However, few investigations have aimed at evaluating and modelling its rheological behaviour.The present paper deals with the three dimensional viscoelastic characterization of epoxy asphalt concrete (EAC) in the frequency domain, focusing on the complex Young’s modulus and the complex Poisson’s ratio. Cyclic compression tests were performed on cylindrical specimens, providing the measurement of axial and transverse strains. A conventional frequency sweep procedure was followed for different test temperatures. In addition, ordinary hot mix asphalt (HMA) specimens were tested as reference. The time-temperature superposition principle and the Huet–Sayegh rheological model were used to analyse the experimental data. Indirect tensile strength and water sensitivity were also evaluated.Results showed that EAC had higher stiffness and thermal sensitivity with respect to HMA. The complex Poisson’s ratio of both EAC and HMA was found to be dependent on temperature and frequency: absolute value ranged from 0.30 to 0.42 and from 0.27 to 0.45, respectively, while the phase angles were lower than 5°.