Affiliations: [a] College of Civil Engineering, Chongqing Jiaotong University, Chongqing 400074, China | [b] School of Materials Science and Engineering, Chongqing Jiaotong University, Chongqing 400074, China | [c] College of Civil Engineering, Chongqing Three Gorges University, Chongqing 404100, China
Correspondence:
[*]
Corresponding author: Ruiqiang Zhao, School of Materials Science and Engineering, Chongqing Jiaotong University, Chongqing 400074, China. Tel.: +86 23 62647166; Fax: +86 23 62652702; E-mail:rqzhao@cqjtu.edu.cn
Abstract: This paper presents a new judging principle for corrosion
testing of steel bars buried in reinforced concrete based on the
self-magnetic flux leakage. The magnetic field signals decrease monotonously
with the increase of the lift-off height of the magnetic sensor, which
denotes the distance between the magnetic sensor and the specimen surface,
for the undamaged area of the reinforcing steel bar while a reversal
phenomenon appears for the corroded area. The lift-off height related to the
reversal point will increase with the increase of the corrosion degree, and
the corroded area could also be extracted from the magnetic field data. The
competition between the demagnetizing field and the magnetic flux leakage
from the corroded area could be used to explain the phenomena. The results
indicate that the lift-off height related to the reversal point can be acted
as the judging criterion for assessing the corrosion degree and the
corrosion area of the reinforcing steel bar. The findings have extensive
application prospect for detecting and evaluating the corrosion degree of
reinforced concrete in engineering practice.
