Rugina C.,Institute of Solid Mechanics of the Romanian Academy |
Toader A.,Elie Carafoli National Institute for Aerospace Research INCAS |
Giurgiutiu V.,Elie Carafoli National Institute for Aerospace Research INCAS |
Giurgiutiu V.,University of South Carolina |
Ursu I.,Elie Carafoli National Institute for Aerospace Research INCAS
Proceedings of the Romanian Academy Series A - Mathematics Physics Technical Sciences Information Science | Year: 2014
This paper describes the electro-mechanical (E/M) impedance method applied to structural health monitoring (SHM) of thin circular plates. The method allows us to identify the local dynamics of the structure directly through the E/M impedance signatures of piezoelectric wafer active sensors (PWAS) permanently mounted to the structure. An analytical model for 2-D thin-wall structures, which predicts the E/M impedance response at PWAS terminals, was developed and validated. The model accounts for axial and flexural vibrations of the structure and considers both the structural dynamics and the sensor dynamics. Calibration experiments performed on circular thin plates with centrally attached PWAS show that the presence of a damage modifies the high-frequency E/M impedance spectrum causing frequency shifts, peak splitting, and appearance of new harmonics. Comparisons between the analytical method, the finite element method, and experiments were performed, with a fabricated structural arc-shape defect. © 2014, The Publishing House of the Romanian Academy. All rights reserved.