Flexural vibrations of beams with delaminations

Abstract

The effect of delamination on the natural vibration characteristics of laminated beam type structures is studied. An analytical model is presented for beams with through-width delaminations parallel to the beam surface located arbitrarily in both the spanwise and thicknesswise directions. The beam is modelled as four separate component segments, each analyzed as an Euler beam. An analysis is presented of the case of vibration when the two segments of the beam in the delamination region are constrained to have identical transverse deformation. A critical assessment of the analytical models available in the literature and a comparative study with the analytical model proposed here is presented. Numerical results for frequencies and mode shapes are presented for various boundary conditions and mode numbers for a wide range of values of the size, thicknesswise and spanwise location of the delamination. Results from an extensive experimental investigation are also presented which show excellent agreement with the analytical results obtained by using the model proposed in this paper.