Holographical Microwave Imaging of Corroded Steel Bars in Concrete
Corrosion assessment of embedded steel in concrete structures is generally performed by electrochemical methods that are not fully nondestructive because the device requires connection to the steel. For practical applications, the development of a truly nondestructive technique for the detection of corrosion is desirable. This paper presents an experimental study of a wideband microwave three-dimensional synthetic aperture radar imaging technique applied to reinforced concrete specimens subjected to corrosion. Two orthogonal wave polarization directions were used for this purpose. Two-dimensional microwave image slices were analyzed and compared with the actual loss of steel measured during the destructive testing. As expected, the results indicated that higher-frequency images have higher spatial resolution, while the signal penetration became more limited at these frequencies. Though the relatively high moisture content significantly increased the dissipative properties against electromagnetic propagation, the technique was capable of differentiating between corroded and non-corroded steel bars.
M. T. Ghasr et al., "Holographical Microwave Imaging of Corroded Steel Bars in Concrete," Materials Journal, vol. 112, no. 1, pp. 115 - 124, American Concrete Institute (ACS), Jan 2015.
The definitive version is available at https://doi.org/10.14359/51686981
Electrical and Computer Engineering
Keywords and Phrases
Corrosion; Nondestructive Evaluation; Reinforcing Steel; Three-Dimensional Microwave Imaging; Bars (Metal); Concretes; Imaging Systems; Imaging Techniques; Radar Imaging; Reinforced Concrete; Synthetic Aperture Radar; Dissipative Properties; ELectrochemical Methods; Electromagnetic Propagation; High Moisture Contents
International Standard Serial Number (ISSN)
Article - Journal
© 2015 American Concrete Institute (ACS), All rights reserved.
01 Jan 2015