Influence of openings and additional mass on vibration of laminated sandwich rhombic plates using IHSDT

In this article, investigations on the influence of openings and additional mass on free vibration analysis of laminated composite sandwich skew plates using improved higher order shear deformation theory (IHSDT) have been done. The IHSDT model satisfies the interlaminar shear stress continuity at the layer interfaces and also ensures zero transverse shear stress conditions at the top and bottom of the plate. The piecewise parabolic shear stress variation across the thickness of each layer is considered. No shear correction factors are required. The 2-D C-0 finite element (FE) model has been developed by authors based on IHSDT. FE model based on IHSDT has been coded in FORTRAN. The problem of C-1 continuity requirement associated with the IHSDT is overcome using an appropriate C-0 FE formulation. The free vibration frequencies of laminated composite and sandwich plates obtained using the present 2-D FE model are in good agreement with the 3-D elasticity results. The influence of the side-to-thickness ratio, skew angles, boundary conditions, and mode shapes is taken into consideration for the present study.