Free vibration analysis of rectangular sandwich plates with compressible core and various boundary conditions

Abstract

Extended higher-order sandwich plate theory is used to analyze the free vibrations of rectangular sandwich plates with compressible core. Accordingly, first-order shear deformation theory is used to model the laminated face sheets. Besides, the in-plane and transverse displacements of the core are assumed to be cubic and quadratic functions of the thickness coordinate, respectively. To deduce the governing equations, Hamilton’s principle is used. Then, based on the Rayleigh-Ritz method, single series expansions with two-variable orthogonal polynomials – namely, the orthogonal plate functions – are considered to approximate the displacement components. Lastly, a generalized eigenvalue problem is solved to obtain the free vibrational characteristics of sandwich plates with both symmetric and anti-symmetric lay-ups subjected to various boundary conditions. The method is validated against the results obtained by different methods in the literature. Finally, the effects of the plate side-to-thickness ratio, in-plane aspect ratio, and core-to-face sheets thickness ratio on the natural frequencies are discussed.

Seismic tremor location of 10 large paroxysmal eruptions of Tungurahua volcano, Ecuador

“…But this model can not successfully explain real data, mainly because it does not take into account reflections at regional borders, which is very common phenomenon in alluvial and sedimentary basins (Cruz-Atienza et al 2016). These border reflections can also generate stationary waves within the basins (Semblat et al 2005), as experiments and models on plate composites predict (Farsani et al 2020). On the other hand, models based on random scatter distributions (Sato et al 2012) use the coda waves of earthquakes and a reference location, being it located at some outcrop surface, to define the FRFs (Mayeda et al 1991; Kato…”

A VAM-Based Equivalent Model for Triangular Honeycomb Sandwich Panels: Comparison with Numerical and Experimental Data

“…The analytical theory of honeycomb sandwich panels began to be coupled with the finite element technique as a result of the aforementioned theoretical progress. For example, Farsani et al [ 18 ] and Wu et al [ 19 ] investigated the free vibrations of composite sandwich panels by using the FOST and global–local high-order deformation theory combined with the finite element method, respectively. As a result, numerical simulations have also become the main approach for investigating the mechanical properties of honeycomb sandwich panels, in addition to carrying out experiments to directly study such structures [ 20 , 21 ].…”