DOI:10.13465j.cnki.jvs.2012.13.023
31 13 JOURNAL OF VIBRATION AND SHOCK Vol. 31 No. 13 2012
210016
: Lamb ; ;
: ; ; ; Lamb ; : V214.8 : A
Damage identification of composite structures based on reconstruction algorithm for probabilistic inspection of damage
YAN HongZHOU Li
State Key Laboratory of Mechanicas and Control of Mechanical Structures
Nanjing University of Aeronautics and AstronauticsNanjing 210016China
Abstract: The reconstruction algorithm for probabilistic inspection of damage RAPID was proposed for continuous online monitoring of composite structures based on wavelet analysis and the theory of probability and statistics. The wavelet analysis was applied to extract the features of the Lamb wave signals in both reference and present states on each sensing path. The difference coefficient between the features was taken as a damage index DI . Thenthe probabilistic method was used to judge whether the DI is caused by the structural damage or the environmental factors. Finallya tomogram generated by the RAPID algorithm was obtained to identify the damage. An experimental study on a composite panel with a 12PZT sensor network was conducted to verify the capability of the RAPID algorithm in damage identification. Experimental results demonstrate that the proposed method is quite feasible and effective for composite structural damage identification. It has certain application value in the practical engineering.
Key words: damage index; wavelet analysis; RAPID; Lamb wave; damage identification
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Fig. 13 Tomogram generated by the RAPID
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