Studies of the Effect of Diffusion-Induced Chloride Binding on Chlorination Life Predictions for Existing Reinforced Concrete Bridges

Ming-Te Liang ； Jiang-Jhy Chang ； Tung-Wei Yu

《Journal of Marine Science and Technology》 20卷4期 (2012/08) Pp. 418-430

https://doi.org/10.6119/JMST-011-0318-2

並列摘要

The chloride ions diffusion is one of important factors of corrosion of reinforced concrete (RC) structures. The total chloride concentration penetrated into concrete can be expressed as the sum of bound and free chloride concentrations. The principal purpose of this paper is to study the chlorination life prediction of existing RC bridges due to chloride binding effect. The investigation method is that the no binding, linear binding, Langmuir and Freundlich adsorption isotherms are substituted into the analytical solutions of linear (diffusivity D = constant) and non-linear (D ≠constant) diffusion equations associated with initial and boundary conditions, respectively. The chlorination life can be calculated from the analytical solutions through the Mathematica software. These theoretical models are used to apply the existing Lin-bian and Dah-jin RC bridges in Taiwan. The results of the present study show that the Langmuir adsorption isotherms is suitable for bridge deck with small concrete cover while the linear binding is suitable for pier and abutment with large concrete cover. The studied results can be provided as a crucial reference for engineering decision-making for repair, strengthening or demolition of existing RC bridges.

並列關鍵字

bridge ； chloride binding ； chlorinational life ； Langmuir isotherm ； Freundlich isotherm

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