Title: Modeling Chloride Transport in Concrete at Pore and Chloride Binding

Author(s): Ki Yong Ann and Sung In Hong

Publication: Materials Journal

Volume: 115

Issue: 4

Appears on pages(s): 595-604

Keywords: chloride; diffusion; modeling; pore size distribution

DOI: 10.14359/51702194

Date: 7/1/2018

Abstract:
The present study concerns modeling of chloride diffusion in concrete by reflecting the pore size distribution and binding of chloride in the cement matrix. As factors that influence the chloride diffusion, water-cement ratio (w/c) and replacement ratio for blended cement concrete were taken. As a result, it was found that an increase in w/c and a decrease in the replacement ratio resulted in an increase in the fraction of effective pore volume for chloride transport, while chloride binding capacity decreases with w/c and increases with the replacement ratio. Also, the higher chloride binding capacity could cause an increase in total chlorides at concrete surface, which could enhance the concentration buildup rate at smaller cover depth in the long term. However, after reaching the limited chloride binding capacity, the diffusion coefficient decreased with time, implying that a reduction of the diffusion rate could be attributed to the chloride binding.