To estimate the overall performance of composites, it is necessary to identify the influence of the buckling and delamination failure. For that reason, a fiber optic sensor was applied to the delaminated composite beams to detect the buckling occurrence and delamination growth. The delaminated composite beams subjected to the compressive load were tested to identify the signal characteristics of the fiber optic sensor. The signals of the fiber optic sensor from buckling or delamination growth were quantitatively evaluated by short time Fourier transform and wavelet transform.
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