Damage Detection of Concrete Beam Based on Embedded PZT Impedance Transducer Encapsulated by Cement

Piezoelectric material, such as, Lead Zirconate Titanate (PZT) can be use as sensing and/or actuating element for structural health monitoring due to its direct and converse piezoelectric effects. In this study, several fabricated PZT impedance transducers encapsulated by cement were embedded into a plain concrete beam to detect the surface crack damage. By monitoring the electromechanical (EM) admittance spectra of the embedded transducers, the structural surface crack damage was investigated. From the experimental results it is found that the shape of the electrical admittance spectra curve of the embedded PZT transducers hardly changes before and after surface crack is of presence, and the EM admittance spectra exhibits tiny change in amplitude with the increase of crack depth, which indicate that the embedded PZT transducers into concrete are insensitive to surface crack damage.