NONLINEAR DYNAMIC BUCKLING OF A CYLINDRICAL-SHELL PANEL MODEL

The dynamic buckling response of a spring-mass, geometrically imperfec t, dissipative model with 3 degrees of freedom simulating a relatively deep cylindrical shell panel under step loading is comprehensively an alyzed. The main feature of the real continuous structure and its corr esponding model is that, under the same Loading statically applied, bo th exhibit snapping. Energy, topological, and geometric considerations allow us to establish qualitative and quantitative criteria leading t o dynamic buckling loads of both dissipative and nondissipative models without integrating the highly nonlinear equations of motion. An a pr iori knowledge of the accuracy of these buckling estimates is successf ully obtained by discussing the geometry of the channel in which the m otion takes place before reaching the escape passage through a saddle (or its neighborhood) with very small negative total potential energy. A comparison of the numerical results obtained by the proposed method with those of Runge-Kutta-Verner scheme shows the reliability and eff iciency of the proposed method.