An analytical model for the characterization of delamination in beams using flexural wave scattering analysis is presented. In the beam model of wave propagation, the beam is divided into four regions; to each of them the beam theory of wave propagation is applied to obtain the wave fields excited by a harmonic load on the beam surface. The solution for the entire beam is obtained in terms of the solution for the respective regions using continuity conditions at the junctions. Numerical results on beam displacement for various delamination sizes, materials and excitation frequencies are presented. Experiments using a scanning laser vibrometer on specimens containing simulated delamination are also conducted. The results are then verified by comparing with those obtained by the Strip Element Method (SEM) and experiment. Good agreement is observed between the present model with SEM and experiment.

Issue Section:
Technical Papers
Keywords:
delamination, ultrasonic materials testing, ultrasonic propagation, structural acoustics, Delamination, Flexural Wave, Strip Element Method, NDE, Dynamic Analysis
Topics:
Delamination, Displacement, Waves, Strips, Excitation, Scattering (Physics)
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