Postbuckling Analysis of Shells of Revolution Considering Mode Switching and Interaction

Abstract

This chapter presents a numerical method for the accurate and efficient advanced postbuckling analysis of thin shells of revolution, subject to torsionless axisymmetric loads. The method is based on the use of small load-disturbances in a nonlinear analysis of shells of revolution under general nonsymmetric loads, and is referred to as the load-disturbance method. By including disturbances in appropriate harmonic modes, the method can model both mode switching and interaction accurately. It may be noted that the load-disturbance method is not easy to apply if the nonlinear analysis is carried out using a general curved shell element, as the specification of harmonic loads is not straightforward. In addition, the analysis is much less efficient. For axisymmetric shell elements using Fourier series approximations for circumferential variations, the method becomes particularly simple as Fourier harmonics are already used. The combination of the semi-analytical axisymmetric shell element and the load-disturbance method thus leads to an elegant and efficient approach of postbuckling analysis, which can model mode switching and interaction efficiently and accurately.