Open AccessProbability distribution and influence factors on corrosion initiation of reinforcing steel induced by chloride
Author(s) -
Faqiang Yu,
Wenchao Liu,
Weiwei Gao
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/780/3/032035
Subject(s) - corrosion , concrete cover , chloride , materials science , reinforced concrete , metallurgy , diffusion , composite material , alkalinity , chemistry , physics , organic chemistry , thermodynamics
Chloride-induced corrosion of steel in reinforced concrete structures is one of the major causes of their deterioration over time. Chlorides from de-icing salts or marine breeze penetrate through the concrete cover and break down the natural protective oxide layer formed around the reinforcements by the strong alkalinity of pore solution. As a matter of fact, the free chloride in concrete could not transport through reinforcing steel and accumulated at front point of reinforcing steel rapidly which made reinforcement corrosion initiation earlier. Therefore, the current studies on corrosion initiation might be hazardous without considering the obstruction action of reinforcing steel. In this paper, the Fick’s second law was used to describe the free chloride concentration evolution in concrete and obstruction action of reinforcing steel was considered. The influences of the variability on boundary chloride concentration, thickness of concrete cover, and chloride diffusion coefficient on cumulative distribution of corrosion initiation of reinforcing steel were studied thoroughly. The obstruction of reinforcing steel gave much influence on corrosion initiation, especially for thinner concrete cover, higher concrete strength, and higher environmental temperature.