Elastoplastic bifurcation and collapse of axially loaded cylindrical shells

In this paper, a shell finite element is designed within the total Lagrangian formulation framework to deal with the plastic buckling and post-buckling of thin structures, such as cylindrical shells. First, the numerical formulation is validated using available analytical results. Then it is shown to be able to provide the bifurcation modes—possibly the secondary ones—and describe the complex advanced post-critical state of a cylinder under axial compression, where the theory is no longer operative.