Correction of chloride threshold concentration and time-to-corrosion due to reinforcement presence

✍ Scribed by H. Yu; W. H. Hartt

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: German
• Weight: 536 KB
• Volume: 62
• Category: Article
• ISSN: 0947-5117
• DOI: 10.1002/maco.200905516

✦ Synopsis

Reinforcement presence affecting corrosion threshold concentration, C t , determination and time-to-corrosion, T i , has been investigated. Elevated C t and decreased T i due to reinforcement physical obstruction on the path of chloride ingression into concrete has been examined with finite element modeling. Results indicated that reinforcement with larger size, better corrosion resistance, less cover thickness, or a more flat leading edge causes more pronounced T i reduction. Experimental results exposed aggregate content discrepancy within reinforced bar vicinity zone. According to this finding, a multi-shell chloride diffusion model, in which specific chloride ion diffusivity in each shell surrounding bar presents, is proposed. The C t results of proposed model are discussed along with those acquired from traditional onedimensional model, in which chloride diffusion follows Fick's second law without considering reinforcement presence, and two-dimensional model with the effect of reinforcement physical obstruction regarded.