Vol.21, Special Issue, 2021, pp. S13–S22
UDC:

Reddy's third-order theory is adopted to analyse the free axisymmetric vibrations of thick circular sandwich plates with a relatively stiff uniform core and membrane facings. Hamilton's principle is used to develop the equations of motion and natural boundary conditions. Numerical solution for frequency equations of simply-supported, clamped and free edged plates are obtained using Chebyshev collocation method. The least three roots obtained are reported as the natural frequency parameters for the first three vibration modes. Validation of the results presented in the paper is done by making comparison with their counterparts accessible in available published works. Results are exhibited numerically and graphically for studying the influence of thicknesses of the core and facings on the natural frequencies. The significance of the proposed model is established by showing that for the estimation of natural frequencies of thick cored circular sandwich plates, previously published models based on first-order shear deformation theory are not sufficient. Mode shapes of the initial three modes for each boundary condition have been plotted.

Keywords: circular sandwich plates, axisymmetric vibrations, Hamilton's principle, Chebyshev collocation technique, Reddy's Theory, mode shapes