Effect of damage in reinforced concrete on carbonation or chloride penetration

✍ Scribed by R. Francois; J.C. Maso

• Publisher: Elsevier Science
• Year: 1988
• Tongue: English
• Weight: 415 KB
• Volume: 18
• Category: Article
• ISSN: 0008-8846
• DOI: 10.1016/0008-8846(88)90033-6

✦ Synopsis

The influence of mechanical loading effects on carbonation or chloride penetration is studied. Specimens are reinforced concrete beams of 3 m long which are stored in a mechanical loading state and in aggressive environments. Carbonated cover depths and chloride contents are measured. The results show that damage at grain/paste interfaces in tensile zones leads to an increase of penetration of aggressives ions.

Intr~uotion

Many researchers (I)(2)(3) have shown that reinforcement corrosion occurred when the concrete cover was carbonated or contaminated by chloride ions. Economic stake is important (4) and so several investigations have been made on this subject.

The penetration of chloride ions is due to a diffusion mechanism, as stated by several authors (5)(6)(?). Chloride content can be calculated by using a diffusion equation which assumes that chemical reactions are negligible. The diffusivity O of chloride ions, for steady-state diffusion, is defined by Fick's law relating the chloride content c(x,t) to the checking depth and the time t :