The present study consists of generating a finite element model of the structure, viz., a slender cantilever plate, using an integrated software package, SDRC -IDEAS, to estimate the changes in various modal parameters, caused by a notch type crack. Additionally, a series of tests were carried out using response measurement equipment to experimentally determine the effect of the imposed defect. This was accomplished via measurement of dynamic response, using both accelerometers and strain gauges, and subsequent test data analysis using I-DEAS. Results obtained from both phases of study showed that the crack could be detected through observation of reduction in natural frequencies for a number of modes. The analytical model, in particular, provided a useful technique of crack location via observed changes in the plots derived from differences in both displacement and rotation mode shapes for cracked plates, with respect to a reference plate. The experimentation performed verified the analytical results, and provided additional insights into changes in damping, residues, and amplitudes of dynamic response for frequency values at, and offset from those associated with the natural modes. This latter phenomena proved to be very sensitive and correlated well with observed changes in frequency.
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