Influence of stress waves on the dynamic progressive and dynamic plastic buckling of cylindrical shells

A new concept is presented for the dynamic elastic-plastic axisymmetric buckling of circular cylindrical shells under axial impact. The phenomena of dynamic plastic buckling (when the entire length of the shell wrinkles before the development of large radial displacements) and dynamic progressive buckling (when the shell folds form sequentially) are analysed from the viewpoint of stress wave propagation resulting from an axial impact. The conditions for the development of dynamic plastic buckling are obtained. A numerical analysis of the buckling phenomena reveals that the material properties together with the geometrical characteristics of the shell determine the particular type of response for high velocity impacts. It is concluded that shells made of strain rate insensitive materials can respond either by dynamic plastic buckling or dynamic progressive buckling, depending on the inertia properties of the shell, while those shells made of strain rate sensitive materials respond always by dynamic progressive buckling. It is shown that the prediction for the peak load, which can develop in a shell for a high velocity impact, depends on the particular yield criterion used in the analysis. (C) 2001 Elsevier Science Ltd. All rights reserved.