Design and performance evaluation of electromechanical impedance instrumented quantitative corrosion measuring probe based on conical rods

Abstract

Previous study has proved that using electromechanical impedance (EMI) instrumented bar-type corrosion measuring probe can realize the quantitative assessment of the corrosion amount. To gain more insights into the working mechanism and design better probes, this work examined a new type of corrosion measuring probe based on the conical rod, and evaluated their performance. Theoretical model of this type of new probes was established based on one dimensional piezo-elasticity theory, and the electrical impedance was derived to obtain first-order resonant and anti-resonant frequencies in longitudinal vibration mode. Two experiments were performed to validate the feasibility of the probe for corrosion measurement, including the artificial uniform corrosion experiment and the accelerated corrosion test. Comparisons between the theoretical predictions and the experimental results from the artificial uniform corrosion experiment were made, and good agreement was found. Effects of piezoelectric patch thickness and cone angle on first resonant and anti-resonant frequencies were also analyzed. In addition, a wireless impedance measurement system was preliminarily realized, which is very promising in developing the low cost and high accuracy online real-time monitoring technology for the pipeline corrosion monitoring.

Modeling and analysis of frequency-variable 2–2 cement-based piezoelectric transducers

“…Further, the fabricated 1D transducers were measured using the impedance analyzer PV520A (Bandera Electronics Co., Ltd, Beijing). The experiment setup is similar to the previous work [39,52]. The specimens were placed on a soft sponge to approximately achieve the free-free mechanical boundaries.…”

Monitoring of crack repair in concrete using spherical smart aggregates based on electromechanical impedance (EMI) technique

“…The EMI technique has been proved to be feasible for monitoring the repair process of concrete cracks [43]. Moreover, this can be combined with the wireless impedance measurement system [44,45], which has a promising application in the field of repair monitoring. However, the piezoelectric element is limited in the piezoelectric patches [43], which hinders the further development and application of EMI technique since the monitoring range of SAs could only reach a certain angle of the patch orientation.…”

Performance study of novel metal corrosion probes based on the adjust method of series and parallel connections

“…However, these statistical indicators rely heavily on the selection of the calculation frequency range, which is not conducive to the improvement of monitoring accuracy [31]. Subsequently, intelligent corrosion monitoring sensors using the offset of the resonance frequency in the impedance signal as a quantitative index have been successively proposed, and there exist a variety of structural forms, such as metal hangers [32], rectangular plates [33], circular plates [34], conical rods [35,36], and stepped rods [37]. Among these, the vibration modes of conical rods and stepped rods are easy to identify and have clear physical significance, and thus are better choices in designing metal corrosion probes.…”

“…In addition, the earlier seriesparallel technique was used for structural damage monitoring at multiple locations, but in this work, corrosion probe with series-parallel technique is used to monitor corrosion damage at the same location. Second, early probes focused on proofof-concept and were mostly parallel-connected [37] and based on a single piezoelectric patch [30,36]. Once the configuration is established, the properties of the probe are fixed.…”