Smart piezoelectric transducers for in situ health monitoring of concrete

This paper presents the results of applying a non-parametric technique to the detection of the presence of damage and the monitoring of damage progression in concrete. The electromechanical impedance method using smart piezoceramic material is utilized in this study. The smart piezoelectric lead-zirconate-titanate (PZT) transducers bonded onto the structures are used to actively provide the local excitation and simultaneously sense the structural dynamic response in high frequency band. The frequency-dependent electric admittance signatures of the piezoelectric transducer are compared with the baseline signatures to determine the status of the health of structures. The damage is quantified by the root-mean-square deviation (RMSD) index. The correlation of the RMSD index with the location and extent of damage is investigated. In this paper, two sets of experimental tests are performed on the concrete beams instrumented with PZT transducers. The findings summarized from the experimental results are confirmed by a series of numerical simulations using finite element analysis. The experimental and numerical results demonstrate the suitability of using, the smart PZT transducers for in situ health monitoring, of structural integrity in civil infrastructures using concrete.