Plastic axisymmetric collapse of thin-walled circular cylinders and cones under uniform external pressure

This paper reports on two theoretical investigations and an experimental investigation into the plastic axisymmetric buckling of two thin-walled conical shells and several thin-walled circular cylindrical shells, under uniform external pressure. One of the theoretical investigations was a non-linear finite element solution for plastic axisymmetric buckling, which gave good results. The other theoretical solution was for the plastic non-symmetric bifurcation buckling of thin-walled circular cylinders. This second solution was a very simple one and, although it was based on plastic lobar buckling, it gave very good predictions for plastic axisymmetric collapse. This latter observation prompted the conclusion that there may be a link between plastic lobar buckling and plastic axisymmetric buckling. (C) 1998 Elsevier Science Ltd. All rights reserved.