Crack detection in beam-like structures bynonlinear harmonic identification
Journal Title: Frattura ed Integrità Strutturale - Year 2014, Vol 8, Issue 29
Abstract
The dynamic behavior of beam-like structures with fatigue cracks forced by harmonic excitation ischaracterized by the appearance of sub and super-harmonics in the response even in presence of cracks withsmall depth. Since the amplitude of these harmonics depends on the position and the depth of the crack, anidentification technique based on such a dependency can be pursued: the main advantage of this method relieson the use of different modes of the structure, each sensitive to the damage position in its peculiar way. In thisstudy the identification method is detailed through numerical examples tested on structures of increasingcomplexity to evaluate the applicability of the method to engineering applications. The amount of data to obtaina unique solution and the optimal choice of the observed quantities are discussed. Finally, a robustness analysisis carried out for each test case to assess the influence of measuring noise on the damage identification.
Authors and Affiliations
Paolo Casini, Fabrizio Vestroni, Oliviero Giannini
Keywords
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- EP ID EP126626
- DOI 10.3221/IGF-ESIS.29.27
- Views 71
- Downloads 0
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