A numerical axisymmetric collapse analysis of viscoplastic cylindrical shells under axial compression

Circularcylindrical shells are frequently used as structural components because of their high strength and their ability to absorb energy during complete structural collapse. Total collapse analyses have mainly been based on experimental work and approaches inspired by this. However, in the last few years, powerful numerical tools have been available and numerical collapse analyses have become more attractive.

This paper presents results from an axisymmetric numerical collapse analysis. The analysis is based on a finite rotation shell theory accounting for contact between the shell walls. The strains are assumed to remain small and the shell material is described by an elastic–viscoplastic model. The sensitivity of the collapse behaviour is demonstrated with respect to parameters such as initial imperfections, thickness of the shell, material parameters and rate of deformation.

Comparisons between the results numerically obtained and approaches found in the literature are presented. Good agreement was found for the folding length of the developed collapse pattern whereas small differences between the mean crushing loads was observed. Furthermore, it was noted that the developed collapse pattern was strongly dependent on the strain hardening of the material.