This paper describes the utilization of Electro-Mechanical (E/M) impedance method for structural health monitoring of thin plates. The method allows the direct identification of structural dynamics by obtaining its E/M impedance or admittance signatures. The analytical model for two-dimensional structure was developed and verified with experiments. Good matching of experimental results and calculated spectra was obtained for axial and flexural components. The ability of the method to identify the presence of damage was investigated by performing an experiment where the damage in the form of crack was simulated with an EDM slit placed at various distances from the sensor. It was found that the crack presence dramatically modifies the E/M impedance spectrum and this modification decreases as the distance between the sensor and the crack increases. Several overall-statistics damage metrics, which may be used for on-line structural heath monitoring, were investigated. Among these candidate damage metrics, the αth power of the correlation coefficient deviation, CCDα,3< α <7, used in the high frequency band 300-450 kHz, was found to be most successful. Careful selection of the high frequency band and proper choice of the appropriate damage metric were found to be essential for successful damage detection and structural health monitoring.
Get full access to this article
View all access options for this article.
References
1.
Airey, J.1911. “The Vibration of Circular Plates and their Relation to Bessel Functions,”Proc. Phys. Soc., London, 23: 225-232.
2.
Ayres, T. , Chaudhry, Z. and Rogers, C. 1996. “Localized Health Monitoring of Civil Infrastructure via Piezoelectric Actuator/Sensor Patches,” In: Proceedings, SPIE’ s 1996 Symposium on Smart Structures and Integrated systems, SPIE, Vol. 2719. pp. 123-131.
3.
Chaudhry, Z. , Sun, F.P. and Rogers, C.A. 1994. “Health Monitoring of Space Structures Using Impedance Measurements,” In: Fifth International Conference on Adaptive Structures, Sendai, Japan. 5-7 December. pp. 584-591.
4.
Chaudhry, Z. , Joseph, T., Sun, F. and Rogers, C. 1995. “Local-Area Health Monitoring of Aircraft via Piezoelectric Actuator/Sensor Patches,” In: Proceedings, SPIE North American Conference on Smart Structures and Materials, Vol. 2443. San Diego, CA, 26 Feb-3 March, pp. 268-276.
5.
Childs, B. , Lalande, F., Chaudhry, Z. and Rogers, C.A. 1996. “High-Frequency Impedance Analysis for NDE of Complex Precision Parts,” In: Proceedings of the SPIE’s 1996 Symposium on Smart Structures and Integrated Systems, San Diego, CA, 25-29 February. SPIE Vol. 2717. pp. 237-243.
6.
Colwell, R.C.1936. “The Vacuum Tube Oscillator for Membranes and Plates,”Journal of Acoustical Society of America, 7: 228-230.
7.
Esteban, J. , Chaudhry, Z., Lalande, F. and Rogers, C.A. 1996. “Theoretical Modeling of Wave Propagation and Energy Dissipation in Joints,” In: Proceedings, 37th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, Salt Lake City, UT, 15-17 April.
8.
Giurgiutiu, V. and Zagrai, A.N. 2000. “Damage Detection in Simulated Aging-Aircraft Panels Using the Electro-Mechanical Impedance Technique,”Adaptive Structures and Material Systems Symposium, ASME Winter Annual Meeting, Orlando, Florida. 5-10 November.
9.
Giurgiutiu, V. , Reynolds, A. and Rogers, C.A.2000. “Experimental Investigation of E/M Impedance Health Monitoring of Spot-Welded Structural Joints,” submitted for publication to the Journal of Intelligent Material Systems and Structures, 10(10): 802-812.
10.
Giurgiutiu, V. and Zagrai, A.N.2001a. “Characterization of Piezoelectric Wafer Active Sensors,”Journal of Intelligent Material Systems and Structures, 11: 959-976.
11.
Giurgiutiu, V. and Zagrai, A.N.2001b. “Embedded Self-Sensing Piezoelectric Active Sensors for On-Line Structural Identification,” Submitted to: Transactions of ASME, Journal of Vibration and Acoustics.
12.
Giurgiutiu, V. , Zagrai, A.N. and Bao, J. 2001. “Embedded Active Sensors for In-situ Structural Health Monitoring of Aging Aircraft Structures,” In: Proceedings of the 7th ASME NDE Topical Conference, Vol. 20.
13.
IEEE Std. 176 , 1987. IEEE Standard on Piezoelectricity, The Institute of Electrical and Electronics Engineers, Inc.
14.
Itao, K. and Crandall, S.H.1979. “Natural Modes and Natural Frequencies of Uniform, Circular, Free-Edge Plates,”Journal of Applied Mechanics, 46: 448-453.
15.
Kunukkasseril, V.X. and Swamidas, A.S.J.1974. “Vibration of Continuous Circular Plates,”International Journal of Solids Structures, 10: 603-619.
16.
Liang, C. , Sun, F.P. and Rogers, C.A.1994. “Coupled Electro-Mechanical Analysis of Adaptive Material System-Determination of the Actuator Power Consumption and System Energy Transfer,”Journal of Intelligent Material Systems and Structures, 5: 12-20.
17.
Liessa, A.1969. “Vibration of Plates”, Published for the Acoustical Society of America through the American Institute of Physics, Reprinted in 1993.
18.
Lopez, V. , Park, G., Cudney, H. and Inman, D.J.2000. “A Structural Health Monitoring Technique Using Artificial Neural Network and Structural Impedance Sensors,”Journal of Intelligent Material Systems and Structures, 11(3): 206-214.
19.
Monaco, E. , Franco, F. and Lecce, L.2001. “Experimental and Numerical Activities on Damage Detection Using Magnetostrictive Actuators and Statistical Analysis,”Journal of Intelligent Material Systems and Structures, 11(7): 567-578.
20.
Onoe, M. and Jumonji, H.1967. “Useful Formulas for Piezoelectric Ceramic Resonators and their Application to Measurement of Parameters,”IRE, 4: Part 2.
21.
Park, G. , Cudney, H. and Inman, D.J.2000a. “An Integrated Health Monitoring Technique using Structural Impedance Sensors,”Journal of Intelligent Material Systems and Structures, 11(6): 448-455.
22.
Park, G. , Cudney, H. and Inman, D.J.2000b. “Impedance-Based Health Monitoring of Civil Structural Components,”ASCE Journal of Infrastructure Systems, 6(4): 153-160.
23.
Park, G. , Cudney, H. and Inman, D.J.2001. “Feasibility of Using Impedance-based Damage Assessment for Pipeline Systems,”Earthquake Engineering and Structural Dynamics Journal, 30(10): 1463-1474.
24.
Pugachev, S.I. , Ganapol’sky, V.V., Kasatkin, B.A., Legusha, F.F. and Prud’ko, N.I.1984. “Handbook Piezoceramic Transducers,”Sudostroenie, St.-Petersburg (In Russian).
Soedel, W.1993. Vibrations of Plates and Shells, Marcel Dekker, Inc.
27.
Sun, F.P. , Liang, C. and Rogers, C.A. 1994. “Experimental Modal Testing Using Piezoceramic Patches as Collocated Sensors-Actuators, In: Proceeding of the 1994 SEM Spring Conference and Exhibits, Baltimore, MI, 6-8 June.
28.
Sun, F.P. , Chaudhry, Z., Rogers, C.A. and Majmundar, M. 1995. “Automated Real-Time Structure Health Monitoring via Signature Pattern Recognition,” In: Proceedings, SPIE North American Conference on Smart Structures and Materials, San Diego, CA, 26 February-3 March. Vol. 2443. pp. 236-247.
29.
Tseng, K.K.-H. , Bhalla, S. and Gupta, A.2000. “Performance of Smart Piezoceramic Patches in Health Monitoring of a RC Bridge,”Smart Materials and Structures, 9(4): 533-542.
30.
Tseng, K.K.-H. , Soh, C.K. and Naidu, A.S.K.2001. “Non-Parametric Damage Detection and Characterization using Smart Piezoceramic Material,”Smart Materials and Structures (in press).
31.
Wah, T.1962. “Vibration of Circular Plates,”Journal of Acoustical Society of America, 34: 275-281.
32.
Zagrai, A.N. and Giurgiutiu, V.2001. “Utilization of Electro Mechanical Impedance Method for Structural Identification of Circular Plates,” REPORT# USC-ME-LAMSS-2001-104 November 7.
