Finite element modelling of chloride removal from concrete by an electrochemical method

This paper presents a finite element model for simulating the transport behaviour of ions in a porous medium when a constant DC current density is applied through electrode pairs emplaced in the medium. The model is then applied to predict the mass transport associated with electrochemical chloride extraction from hydrated cement paste. Numerical results are compared with those obtained in experiments of various duration. Effects of externally applied current density, treatment period, diffusion coefficients, ionic binding, boundary conditions and medium porosity on the efficiency of chloride extraction are discussed.

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