Modelisation bidimensionnelle des cylindres fortement raidis
Keywords:
stiffened shell, buckling, smeared technic, discret integration, plasticityAbstract
A numerical method for strongly axially stiffened shells is presented. This type of shell is reinforced by a few number of stijfners with an important section, so consequently are vulnerable to local buckling. The originality of our method is to solve the problem by a bidimensionnal calculation associated with a Fourier development. The stiffened shell is consider as a multi-layer shell : one layer represents the shell and another orthotropic one the stijfners familly. Then we calculate the stiffness contribution of each layer by a classical axial integration and a discret circumferencial integration for the stiffeners. This numerical method is introduced in the INCA code of CAST EM system and used for the buckling of imperfect shells in the elastic field and also in the plastic field with a global yield criterion. It's compared with the elasto-plastic results of a tridimensionnal calculation on the buckling of a silo on column support.
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References
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