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Indexed by:会议论文

Date of Publication:2015-01-01

Included Journals:Scopus

Abstract:In the electromechanical impedance (EMI) technique, piezoelectric lead zirconate titanate (PZT) transducer is employed as both sensor and actuator based on the direct and converse piezoelectric effects of PZT materials. The basic concept of the EMI technique is to use high-frequency excitations to monitor changes in the local area of the host structure caused by damage. By adopting the "effective impedance" concept, this paper proposes a three-dimensional (3D) electromechanical impedance model for the embedded PZT transducer. Based on the new 3D impedance model, a modified methodology for monitoring the strength gain is proposed. In the proposed method, the changes in the host structure are monitored by using the structural mechanical impedance, which is extracted from the measured raw electromechanical admittance signatures. Then, the inherent properties of the host structure can be detected with the higher accuracy than with the raw admittance signals only. In this paper, the inherent properties of a concrete beam with embedded PZT transducers during curing age were monitored by the proposed methodology. The efficiency and feasibility of the proposed method is verified by the experiment results. ? 2015, International Society for Structural Health Monitoring of Intelligent Infrastructure, ISHMII. All rights reserved.