| Smart Structures and Systems Volume 14, Number 4, October 2014, pages 569-594 DOI: https://doi.org/10.12989/sss.2014.14.4.569 | |
Influence of sharp stiffness variations in damage evaluation using POD and GSM | |
M. Thiene, U. Galvanetto and C. Surace
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| Abstract [Buy Article] | |
| Damage detection methods based on modal analysis have been widely studied in recent years. However the calculation of mode shapes in real structures can be time consuming and often requires dedicated software programmes. In the present paper the combined application of proper orthogonal decomposition and gapped smoothing method to structural damage detection is presented. The first is used to calculate the dynamic shapes of a damaged structural element using only the time response of the system while the second is used to derive a reference baseline to which compare the data coming from the damaged structure. Experimental verification is provided for a beam case while numerical analyses are conducted on plates. The introduction of a stiffener on a plate is investigated and a method to distinguish its influence from that of a defect is presented. Results highlight that the derivatives of the proper orthogonal modes are more effective damage indices than the modes themselves and that they can be used in damage detection when only data from the damaged structure are available. Furthermore the stiffened plate case shows how the simple use of the curvature is not sufficient when analysing complex components. The combined application of the two techniques provides a possible improvement in damage detection of typical aeronautical structures. | |
| Key Words | |
| damage detection; POD; GSM; stiffened panel; threshold approach | |
| Address | |
| M. Thiene and U. Galvanetto:Department of Industrial Engineering, University of Padova, via Marzolo 9, 35131 Padova, Italy; Centre for Space Studies and Activities G. Colombo, University of Padova, via Venezia 15, 35131 Padova, Italy C. Surace: Department of Structural, Geotechnical and Building Engineering, Politecnico di Torino, corso Duca degli Abruzzi 24 – 10129 Turin, Italy | |
