DOI: 10.3724/SP.J.1249.2019.01094

Journal of Shenzhen University Science and Engineering (深圳大学学报理工版) 2019/36:1 PP.94-100

Investigation on current effectiveness in the process of current accelerated corrosion of reinforcing steel

Impressed-current accelerated corrosion has been widely used in the study of steel corrosion. To investigate the actual consumption of impressed current during the accelerated corrosion process, micro-level X-ray computed tomography (XCT) technique is employed to trace the accelerated corrosion process of steel in a mortar sample to quantitatively analyze the mass loss of steel at different stages, with which current effective coefficient of each stage can be further calculated. The experiment results show that XCT technique can achieve non-destructive tracking of the corrosion process, visual characterization of corrosion morphology, and quantitative calculation of corrosion parameters. The calculation of current effective coefficient indicates that due to the influence of depassivation of steel, electrolysis of water and natural corrosion, the current effective coefficient varies in different corrosion stages. Before the cracking of concrete cover, depassivation and electrolysis lower the coefficient. After cracking, the coefficient is magnified by natural corrosion.

Key words:building materials,reinforced concrete,impressed-current accelerated corrosion,current effective coefficient,X-ray computed tomography

ReleaseDate:2019-01-28 09:56:36

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