ABSTRACT
This chapter presents a brief literature review regarding the analysis of the electromechanical impedance (EMI) technique in aluminum structures, focusing on the impedance measurement, the correct design of Pb-lead zirconate titanate (PZT) transducers, and the appropriate frequency range selection for optimal performance in structural health monitoring (SHM) systems. It presents the basic principle of SHM based on the EMI technique and some issues related to its applications in real-world structures, such as the electrical impedance measurement, transducer loading effect, design of PZT patches, and the frequency range selection. The methodology uses the electromechanical relationship in to analyze the sensitivity of the PZT transducer in function of the frequency and mechanical impedance of the host structure. SHM systems are designated to detect, in real-time or in an appropriate time, structural damage. Several methods have been developed for damage detection in SHM, such as wave propagation, vibration-based methods, acoustic emission, comparative vacuum, and EMI.
