Combined effect of compressibility, height and thickness on the nonlinear behaviour of polyurethane, simply-supported spherical shells under apical loads

Abstract

Previously, the effect of compressibility on the nonlinear buckling behaviour of thin, polyurethane, simply-supported spherical shells subjected to apical loads has been presented without considering the orders of the thickness and height of the spherical shells. In the meantime; it has been observed that although the variations of the thickness and height of the spherical shells do not affect the comments made for the effect of the compressibility on the buckling loads, they do affect the comments made for the effect of the compressibility on the buckling deflections considerably. In this study; combined effect of the compressibility, height and thickness on the buckling loads, buckling deflections and the apical load-apical deflection diagrams of polyurethane, thin, simply-supported spherical shells subjected to apical loads is investigated. Comparing the force-deflection diagrams corresponding to various values of the parameters pertaining to the compressibility of the material used, the height and the thickness of the shell; the variations of the buckling loads, buckling deflections and forms of the force-deflection diagrams corresponding to the various combinations of the mentioned parameters are discussed.

Keywords

• Compressible material
• finite difference method
• nonlinear analysis
• polyurethane
• spherical shell

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