Rebar corrosion detection in concrete based on capacitance principle

• Published in: Measurement : journal of the International Measurement Confederation Vol. 209; p. 112526
• Main Authors: Han, Xiaofeng, Wang, Penggang, Cui, Dongbo, Tawfik, Taher A., Chen, Zhaoyi, Tian, Li, Gao, Yizhi
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.03.2023
• Subjects: Capacitive Sensor; Concrete; Finite Element; Rebar Corrosion; Capacitive Sensor; Concrete; Rebar Corrosion; Finite Element
• ISSN: 0263-2241; 1873-412X
• DOI: 10.1016/j.measurement.2023.112526

•The different capacitance trends with different corrosion volume expansion ratios.•The critical corrosion point and the rust layer height could be detected.•The rust layer heights have also affected the capacitance values.•The different electrode placement positions have its advantages.•A linear relationship between corrosion thickness and capacitance values. Rebar corrosion is one of the main reasons for the deterioration of RC structures and is of major concern in the construction industry. The detection of rebar corrosion in RC is essential for maintaining building safety and improving structural durability. In this study, rebar corrosion detection based on the capacitance principle was applied and analyzed using numerical simulations and acceleration tests. The critical corrosion point and rust-layer height can be detected using capacitive sensors. Capacitive sensors with different electrode placement positions exhibit several advantages and disadvantages. The electrodes of the capacitance sensor placed in the up and down positions more easily detected rebar corrosion, and the electrodes placed on the left and right sides exhibited higher sensitivity. A formula for the rebar rust-layer height and the relationship between the capacitance and corrosion thickness were established for non-uniform corrosion. Capacitance values were used to evaluate the compactness of the RC samples.