Viscoelastic properties of bituminous composites using multiscale heterogeneous numerical simulation and micromechanical analytical self-consistent model

Abstract

In this work, detailed study is carried out to develop heterogeneous micromechanical modelling based on multiscale technique to investigate complex response of asphalt mixture. The mechanical behavior of this material is very complex and one must take into account the geometry of the microstructure and the mechanical behavior of the different phases. The properties of such heterogeneous material are highly dependent on the volumetric fraction of bitumen, aggregate structure, air void distributions and interfacial bonding strength between bitumen and aggregates. In this study, the considered bituminous composites are mastic, mortar and asphalt mixes. These composites are treated as biphasic composites, composed of a viscoelastic bituminous binder and an aggregate skeleton with linear elastic properties. In the developed multiscale approach, the homogeneous equivalent properties of biphasic composite are transferred from one scale of observation to the next higher scale of observation. The dynamic modulus of the matrix and elastic properties of aggregates were used as input parameters into micromechanical finite element models qualified by heterogeneous micromechanical models. The complex modulus and phase angle were compared to experimental measurements and analytical values obtained by Generalized Self Consistent Scheme (GSCS).