Post-critical Behavior of Moderately Thick Axisymmetric Shells: A Sequential Limit Analysis Approach

The design of some steel shells, like energy absorbers or bumpers, requires the knowledge of their behavior in large deformations. In this paper, the method of sequential limit analysis is presented and applied to axisymmetric shells in order to study their post-collapse response. Although the material behavior is assumed as rigid-plastic, results compare favorably with those produced by elastic-plastic incremental analyses and the procedure appears to be more efficient and numerically stable. Large displacement effects, both of stable and unstable nature, are implicitly accounted for by mesh updating.