Monitoring chloride-induced corrosion in metallic and reinforced/prestressed concrete structures using piezo sensors-based electro-mechanical impedance technique: A review

In metallic, reinforced concrete (RC) and prestressed concrete (PC) structures, corrosion is one of the main problems which adversely affects its service life. Therefore, structural health monitoring (SHM) is essential for performance evaluation and safety maintenance to prevent and reduce engineering accidents. In the field of SHM, corrosion monitoring using piezo sensor-based electro-mechanical impedance (EMI) technique has become a research hotspot. In this paper, the research progress of corrosion monitoring using piezo sensor via EMI technique in metallic, RC, and PC structures during the last two decades was comprehensively reviewed. The basic principle of the EMI technique, development of piezo sensor configurations, and the quantification of corrosion using various statistical methods were discussed. In addition to that, the numerical simulation of corrosion sensor modelling in metallic and RC structures using the EMI technique and the literature studies on qualitative and quantitative analysis performed by the various researchers were also discussed. This review paper will aid the researchers, academicians, and scientists who are venturing into this research area in conducting proper experiments related to chloride-induced corrosion either in metallic/RC/PC structures by choosing appropriate sensor configurations, placement, acquisition, correlation, and calibration.