Influences of obstruction action of reinforcing bar on chloride diffusion and corrosion initiation

Chloride-induced corrosion of reinforcing steel causes reinforced concrete structures performance deterioration over time in marine environment. Few researches concern the influences of obstruction action of reinforcing bar on chloride diffusivity in concrete and the prediction results about corrosion initiation or service life may be non-conservative. In this paper, the influencing factors of chloride diffusion coefficient and chloride binding isotherms in concrete are reviewed comprehensively. The two-dimensional FEM models considering insulation boundary of bar for chloride diffusion are built. Chloride concentration field and contour at corner of square cross-section and in front of reinforcing bar are present. Finally, the influences of boundary conditions, c d (concrete cover to reinforcing bar diameter ratio) and obstruction action of reinforcing bars on corrosion initiation predictions are discussed thoroughly.