Influence of PZT patch geometry and location on electro-mechanical Impedance signatures of corroded square steel bars
Mallika Alapati1 and Soujanya Jakkula1
Corresponding Author : Mallika Alapati
Recieved : 25-November-2024; Revised : 25-January-2026; Accepted : 29-January-2026
Abstract
Damage mechanisms such as corrosion in steel structural members need to be detected at an early stage to prevent flexural failures and to enable timely preventive measures that enhance the residual service life of the structure. Corrosion reduces the effective cross-sectional area of structural elements, leading to increased stress concentrations. In recent years, sensor-based technologies have gained significant attention for detecting, localizing, and characterizing such damage in structures. The objective of the present study is to exploit the coupling property between the mechanical impedance of the host structure and a lead zirconate titanate (PZT) patch. The study further investigates variations in electro-mechanical impedance (EMI) signatures for real-time corrosion monitoring. Numerical analyses are carried out on a smart cantilever beam instrumented with a PZT patch, considering both corroded and uncorroded conditions. The numerical results are presented and discussed for two different patch lengths, multiple patch locations, and varying corrosion depths. The influence of patch geometry, specifically patch length, on admittance signatures resulting from corrosion damage in the host steel structure is evaluated. Harmonic excitation results indicate that shifts and increases in conductance peak magnitudes are sensitive to both corrosion depth and patch length. When the patch length is doubled, the conductance peak magnitudes increase, demonstrating that the actuating and sensing capabilities of the EMI technique are strongly influenced by patch length. Furthermore, the effect of patch location on sensitivity is found to be insignificant, which can be attributed to the relatively small length of the steel bar considered in this study.
Keywords
Electro-mechanical impedance, Corrosion monitoring, PZT sensor, Structural health monitoring, Conductance signature, Steel structures.
Cite this article
Alapati M, Jakkula S. Influence of PZT patch geometry and location on electro-mechanical Impedance signatures of corroded square steel bars. International Journal of Advanced Technology and Engineering Exploration. 2026;13(136):366-379. DOI : 10.19101/IJATEE.2024.111102084
