Title: Effect of Localized Mechanical Damage on Gas Permeability and Chloride Migration into High Performance Concrete

Author(s): A. Djerbi, P. Turcry, S. Bonnet, and A. Khelidj

Publication: Symposium Paper

Volume: 234

Issue:

Appears on pages(s): 269-282

Keywords: chloride; cracking; high performance concrete; migration; permeability

DOI: 10.14359/15942

Date: 3/22/2006

Abstract:
The effect of cracking on chloride migration and gas permeability were investigated on w/c = 0.49 high performance concrete. Cracks of designed widths (ranging from 50 µm to 700 µm) were induced in the concrete specimen using a controlled splitting tensile test. Gas permeability and chloride migration are measured before and after loading. Chloride migration coefficients are measured by migration test under steady state condition. Results indicate that the gas permeability of cracked samples increased with increasing crack width. A relationship was obtained between the chloride migration coefficient and the open area of crossing cracks and a good comparison between the measurement and numerical simulation was obtained. This result confirms the validity of the model of transfer in parallel. A comparison between the gas permeability and chloride migration coefficient was given. This indicates that the gas permeability is significantly more sensitive than the chloride migration coefficient with respect to the crack widths used in this study.