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http://dx.doi.org/10.4334/JKCI.2003.15.6.778

Influence of Relative humidity on the CO2 Diffusion Coefficient in Concrete  

Oh, Byung-Hwan (Dept. of Civil Engineering, Seoul National University)
Jung, Sang-Hwa (Dept. of Civil Engneering, Jeonju University)
Lee, Myung-Kun (Dept. of Civil Engneering, Jeonju University)
Publication Information
Journal of the Korea Concrete Institute / v.15, no.6, 2003 , pp. 778-784 More about this Journal
Abstract
The carbonation of concrete is one of the major factors that cause durability problems in concrete structures. The rate of carbonation depends largely upon the diffusivity of carbon dioxide in concrete. The purpose of this study is to identify the diffusion coefficients of carbon dioxide for various concrete mixtures. To this end, several series of tests have been planned and conducted. The test results indicate that the diffusion of carbon dioxide reached the steady-state within about five hours after exposure. The diffusion coefficient increases with the increase of water-cement ratio and decreases with the increase of relative humidity at the same water-cement ratio. The content of aggregates also influences the diffusivity of carbon dioxide in concrete. It was found that the diffusion coefficient of cement paste is larger than that of concrete or mortar. The experimental study of carbon dioxide diffusivity in this study will allow more realistic assessment of carbonation depth in concrete structures.
Keywords
carbonation; gas diffusivity measuring system; $CO_2$ diffusion coefficient; relative humidity;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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