Piezo‐Transducers for Structural Health Monitoring and Non‐Destructive Evaluation

This chapter covers the relevant details of structural health monitoring (SHM) using Lead (Pb) zirconate titanate (PZT) patches, operating in both global as well as local modes. It presents the various aspects of SHM using PZT transducers, beginning with basic aspect of PZT material. PZT, the most widely used piezoceramic, is a solid solution of lead zirconate and lead titanate. In addition to the basic versions, namely, the PZT and the PVDF, the piezo industry today manufactures newer types of packaged piezo based sensors and actuators endowed with specific properties and meant for specific industrial applications. The chapter includes the specific theoretical and practical details of employing PZT patches for SHM. It focuses on employing the PZT patch as a global dynamic response sensor through dynamic strain measurement. The electro-mechanical impedance (EMI) technique, invented by Liang et al. (1994), employs the PZT patch both as an actuator and a sensor simultaneously for SHM.