Influence of coupled chemo-mechanical process on corrosion characteristics in reinforcing bars

Abstract

We studied the corrosion characteristics of reinforcing bars in concrete under different corrosion conditions. The area-box (AB) value was used to classify the shape of pitting corrosion morphology in meso-scale, and fractographs of reinforcing bars with different corrosion morphology were discussed in micro- and macro-scales. The results show that the existence of the tensile stress affects the corrosion characteristics of reinforcing bars. The pitting morphology and fractograph of reinforcing bars exhibit a statistical fractal feature. The linear regression model fits the relationship between fractal dimensions of corrosion morphology and fractal dimension of fractograph fairly well. Using fractal dimension as the characterization parameter can not only reflect the characteristics of pitting corrosion morphology in reinforcing bars, but also reveal the fracture feature of corroded reinforcing bars.

Keywords

reinforcing bar / chemo-mechanical coupling / pitting corrosion morphology / fractograph / fractal

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