Modelisation de la lixiviation des materiaux cimentaires : Methode d'homogeneisation avec une approche asymptotique a double echelle

ABSTRACT We present in this work a modeling of calcium leaching in concrete by taking into account the influence of aggregates. The modeling consists of the derivation of the microscopic equation governing the average concentration field in the equivalent medium as well as the determination of the macroscopic transport parameters. The homogenization method allows estimating the diffusion and tortuosity tensor to be introduced in the macroscopic formulation of mass conservation law. These estimates depend on the morphological parameters which represent the geometry of the domain occupied by the phase in which the diffusion process takes places. Finally, numerical simulations are compared with experimental results on concrete.