A numerical investigation into the plastic buckling of circular cylinders

It has been long known that finding a thoroughly good agreement with experimental results for the buckling loads of circular cylinders in the plastic range constitutes a very difficult task, beyond the same as well challenging problem in the elastic range. This paper attempts to contribute to the understanding of this issue by discussing a few numerical examples in comparison with some classical experimental results reported by Blachut et al. (1996) and Batterman (1965). It is shown that finite-element analyses grounded on the hypo-elasticity-based extension of small-strain theory of plasticity to geometrically nonlinear problems lead to good agreement with experimental results, although in some cases the sensitivity to the amount and shape of imperfection plays an important role, a fact which leaves open issues in terms of fully predictive capability of the computational models.