Predictions of the frequencies of bending-torsion coupled laminated composite plates with discontinuities: Novel analytical modeling and experimental validation
Date
2017-11Type
ArticleAuthor
Shaat, M.
Aidi, B.
Case, S.W.
Abdelkefi, A.
Metadata
Show full item recordAbstract
A novel analytical model that accurately represents the free vibration response of intact/damaged composite
plates accounting for the bending-torsional coupling is developed. Unlike the existing models for
the bending-torsion vibrations of composite plates, in the present model, the equations of motion are
derived in an uncoupled form. It is then easier to derive analytical solutions for composite plates under
coupled bending-torsion vibrations. In addition, for the first time, analytical solutions for the free bending
and torsional vibrations of cantilever and clamped-clamped laminated composite plates with discontinuities
including circular holes, rectangular holes, notches, and internal and edge cracks are easily obtained.
Shifts in the natural frequencies due to discontinuities are modeled where the reductions in the plate
stiffnesses are related to the amount of the energy release rate due to a defect formation. In order to verify
the accuracy of the proposed model and the derived solutions, the proposed model is compared to the
available conventional models. Moreover, experimental measurements of the free bending and torsional
vibrations of carbon-fiber-laminated composite plates with circular holes is performed. A set of finite element
analyses are carried out and compared to the experimental and the proposed model results. Then, a
parametric study is presented in order to investigate the effects of the discontinuity size and location on
the bending and torsional natural frequencies of laminated composite plates with various forms of discontinuities.
The performed analyses demonstrate the accuracy of the proposed models to represent
the free vibrations of laminated composite plates with discontinuities.