Monitoring of chloride-induced corrosion in steel rebars

ABSTRACT

Chloride-induced corrosion is very serious for steel rebar, because chloride-induced corrosion causes local disruption in the passive layer of the steel, forming surface pits. This paper proposes a novel corrosion monitoring method for steel rebars on the basis of the stress concentration in the plane stress condition caused by chloride-induced corrosion. The fundamentals of corrosion monitoring and the design concept of the proposed sensor are illustrated. The influence factors for corrosion monitoring are simulated to improve the sensitivity. Potentiostatic accelerated corrosion tests are conducted to evaluate the efficacy. The studies indicate that this indirect method for monitoring changes of physical properties caused by corrosion is effective. Influence factors in chloride-induced corrosion can be neglected, as compared with electrochemical techniques. The proposed corrosion monitoring method can provide useful information to evaluate the risk of corrosion initiation and propagation for steel rebars.

KEYWORDS:

• Chloride-induced corrosion
• stress concentration
• plane stress condition
• monitoring
• steel rebar

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Chengming Lan http://orcid.org/0000-0001-8317-8303

Muhuiti Tuerhan http://orcid.org/0000-0002-2912-5128

B. F. Spencer http://orcid.org/0000-0003-0517-7908

Additional information

Funding

This study is financially supported by the National Key R&D Program of China (Grant No. 2017YFC0806100), the NSFC project (Grant No. 51478039), Beijing Nova program (Grant No. Z151100000315053), the CSC Scholarship (No. 201606465033), the Program of International S&T Cooperation (Grant No. 2015DFG82080) and the Ningbo Science and Technology Project (No. 2015C110020).