Stability of S-FGM Annular Spherical Shells with Ceramic – Metal – Ceramic Layers under External Pressure
Main Article Content
Abstract
This paper presents an analytical approach to investigate the nonlinear stability of thin annular spherical shells made of functionally graded materials (FGM) with ceramic – metal – ceramic layers (S-FGM) under uniform external pressure and resting on elastic foundations. Material properties are graded in the thickness direction according to a Sigmoi power law distribution in terms of the volume fractions of constituents (S-FGM). Equilibrium and compatibility equations for annular spherical shells are derived by using the classical thin shell theory in terms of the shell deflection and the stress function. Approximate analytical solutions are assumed to satisfy simply supported boundary condition and Galerkin method is applied to obtain closed – form of load – deflection paths. An analysis is carried out to show the effects of material and geometrical properties and combination of loads on the stability of S-FGM annular spherical shells.
Keywords: Nonlinear stability, S-FGM annular spherical shells, elastic foundations, external pressure.
References
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