Imperfection sensitivity and postbuckling analysis of elastic shells of revolution

The imperfection sensitivity of thin shells of revolution has been a topic of great interest to researchers and designers. With the gradual emergence of the new approach of structural design based on advanced numerical simulation, the efficient and accurate prediction of the behaviour of imperfect shells has recently assumed new significance. This paper first presents an efficient semi-analytical finite element formulation for the nonlinear analysis of imperfect shells of revolution subject to general nonsymmetric loads. Both the applied loads and the initial geometric imperfections may take any form and are approximated by Fourier series expansions. Application of the analysis to study the effects of geometric imperfections on the behaviour of shells of revolution is then presented to demonstrate the accuracy and capability of the present method and the imperfection sensitivity of shell structures. As a special case of the present formulation, two different approaches are also presented for the postbuckling analysis of perfect thin shells of revolution under axisymmetric loads. The accuracy and capability of both methods are demonstrated using a number of numerical examples, which also allows some new insight to be gained into the postbuckling behaviour of perfect shells of revolution.