A 36 DOF Symmetrically Laminated Triangular Element with Shear Deformation and Rotatory Inertia

Abstract

An approach is presented in the formulation of a 36 d.o.f. symmetrically laminated composite triangular plate element including the enect of shear deformation for free vibra tion analysis. The strain energy of plates can be expressed as the sum of the flexural and shear strain energies. The total displacement is expressed as the sum of the displacement due to bending and that due to shear deformation. Thus only the displacement due to bend ing appear in the flexural strain energy and the displacement due to shear deformation ap pear in the shear strain energy. Numerical results for natural frequencies for a range of dif ferent isotropic, orthotropic and anisotropic plates with various thickness-to-length ratios are obtained and compared with various alternative solutions available in the literature to demonstrate the valid range of applicability of this approach for the free vibration of plates with the effect of shear deformation.

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