Finite-Element Predictions of Transient Elastic-Plastic Large Deflections of Stiffened and/or Unstiffened Rings and Cylindrical Shells

A solution procedure which employs the spatial finite-element method together with the temporal finite-difference method is presented for predicting transient elastic-plastic large-deflection responses of structures. Assume-displacement finite-element formulations have been developed in detail for arbitrarily-curved-beam elements and quadrilateral cylindrical-panel elements; specializations to represent straight-beam and flat-plate elements are included. Emphasis has been given to account for geometric stiffeners as well as variable thickness, multilayer, multi-material construction. With the aid of a breadboard computer program, the procedure has been used to predict the transient elastic-plastic large-deflection responses of impulsively-loaded single-layer, singele-material unstiffened and stiffened rings and cylindrical panels for which high quality experimental data and/or independent predictions exist. The feasibility of developing a combined finite-element and finite-difference procedure to represent spatial quantities in structural analysis has been examined in a preliminary fashion. (Modified author abstract)