Damage detection in beams by wavelet analysis

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2007

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Yanılmaz, Hüseyin

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In this thesis, a method proposed by Han et al. [40] for detecting and locating damage in a structural member was adapted. The method was based on the energies that were calculated from the CWT coefficients of vibrational response of a cantilever beam. A transverse cut at varying depths was introduced. The presence and location of crack was investigated by processing experimentally acquired acceleration signals. Results of modal analysis and wavelet analysis of the beam with different cut depths were compared. In addition, effect of using different mother wavelets in CWT analysis for damage detection capability was investigated. Acceleration data were analyzed through CWT at different scales and CWT coefficients were calculated. Those CWT coefficients obtained from different scales were evaluated from the standpoint of damage detection. Effectiveness of energy indices associated with CWT coefficients in damage detection was demonstrated as independent of the type of mother wavelet.

Subject Keywords

Mechanical engineering.

URI

http://etd.lib.metu.edu.tr/upload/12609162/index.pdf
https://hdl.handle.net/11511/17305

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

H. Yanılmaz, “Damage detection in beams by wavelet analysis,” M.S. - Master of Science, Middle East Technical University, 2007.