Analytical Model for Square Root Increase of Surface Chloride Concentration and Decrease of Chloride Diffusivity
Publication: Journal of Materials in Civil Engineering
Volume 28, Issue 4
Abstract
An analytical model of chloride diffusion in concrete structures is derived mathematically for a condition with a square-root increase of surface chloride concentration and a decrease of chloride diffusivity in the initial exposure period. This model is validated with four sets of chloride profiles measured by other researchers on concrete samples containing a few types of cementitious materials. The validation results indicate that the new model is accurate and suitable for the abovementioned diffusion condition with the average coefficient of determination () between the modeled results and the measured chloride profiles being very close to 1 (i.e., ). The model can be used to predict the chloride concentration profile after undergoing diffusion for a certain period in the initial exposure period, which can then be integrated with the profile outcomes modeled for the subsequent exposure periods with different diffusion conditions to determine the corrosion initiation period as a main part of concrete structure’s service life.
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Acknowledgments
Thanks are given to Zhou’s Concrete Consulting Pty, Ltd. for sponsoring this research.
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Information & Authors
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Published In
Journal of Materials in Civil Engineering
Volume 28 • Issue 4 • April 2016
Copyright
© 2015 American Society of Civil Engineers.
History
Received: Jun 10, 2015
Accepted: Sep 9, 2015
Published online: Oct 30, 2015
Discussion open until: Mar 30, 2016
Published in print: Apr 1, 2016
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