This work showsthechloridetransportequationsatthemacroscopicscaleinnon-saturated concrete. Theequationsinvolvediffusion, migration, capillary suction, chloride combination and pre- cipitation mechanisms. The material is assumed to be infinitely rigid, though the porosity can change under influence of chloride binding and precipitation. The involved microscopic and macroscopic properties…
This work showsthechloridetransportequationsatthemacroscopicscaleinnon-saturated concrete. Theequationsinvolvediffusion, migration, capillary suction, chloride combination and pre- cipitation mechanisms. The material is assumed to be infinitely rigid, though the porosity can change under influence of chloride binding and precipitation. The involved microscopic and macroscopic properties of the materials are measured by standardized methods. The variables which must be im- posed on the boundaries are temperature, relative humidity and chloride concentration. The output data of the model are the free, bound, precipitated and total chloride ion concentrations, as well as the pore solution content and the porosity. The proposed equations are solved by means of the finite element method (FEM) implemented in MATLAB (classical Galerkin formulation and the stream- line upwind Petrov-Galerkin (SUPG) method to avoid spatial instabilities for advection dominated flows).