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This and the following 2 slides are from:
Takaya Kobayashi and Yasuko Mihara (Mechanical Design & Analysis Corporation Tokyo, Japan), “Postbuckling Analyses of Elastic Cylindrical Shells under Axial Compression”, 2009 SIMULIA Customer Conference
ABSTRACT: In the design of a modern lightweight structure, it is of technical importance to assure its safety against the buckling under the applied loading conditions. For this issue, the determination of the critical load in an ideal condition is not sufficient, but it is further required to clarify the postbuckling behavior, that is, the behavior of the structure after passing through the critical load. One of the reasons is to estimate the effect of practically unavoidable imperfections on the critical load and the second is to evaluate the ultimate strength to exploit the load-carrying capacity of the structure. For the buckling problem of circular cylindrical shells under axial compression, a number of experimental and theoretical studies have been made by many researchers. In the case of the very thin shell that exhibits elastic buckling, experimental results show that after the primary buckling, secondary buckling takes place accompanying successive reductions in the number of the circumferential waves at every mode shift on one-by-one step. In this paper we traced this successive buckling of circular cylindrical shells using the latest in general-purpose FEM technology. We carried out our studies with three approaches; one is to use the arc-length method (the modified Riks method), the second is static stabilizing with the aid of (artificial) damping especially for the local instability and the third is to use the explicit dynamic procedure. The studies accomplished the simulation of the successive buckling following unstable paths, and show good agreement with the experimental results.
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