Title: Effect of Cracking on Chloride Diffusion Coefficient of Concrete

Author(s): Assia Djerbi Tegguer, Stephanie Bonnet, and Abdelhafid Khelidj

Publication: Symposium Paper

Volume: 289

Issue:

Appears on pages(s): 1-14

Keywords: chloride; cracking; diffusion; high-performance concrete; durability.

DOI: 10.14359/51684268

Date: 9/14/2012

Abstract:
The goal of this research was to study the effects of crack width in concrete on chloride diffusion. Three different concretes were tested, one ordinary concrete (OC) and two high- performance concretes one made without silica fume (HPC) and the other with silica fume (HPCSF). The average crack widths, ranging from (1.1810-3 in. [30 μm] to 910-3 in. [250 μm]), were induced using a splitting tensile test. Chloride diffusion coefficients of concrete were evaluated using a steady state migration test. The results showed that the diffusion coefficient of uncracked HPCSF was less than HPC and OC, but cracking changed the material behavior in terms of chloride diffusion. The diffusion coefficient through cracked concrete, Dcr, is not dependent on material parameters and becomes constant when the crack width is higher than 310-3 in. (80 μm), at which point the value obtained is the diffusion coefficient in a free solution.