THERMOELASTOVISCOPLASTIC BUCKLING BEHAVIOR OF CYLINDRICAL-SHELLS

The thermoelastoviscoplastic buckling behavior of cylindrical shells u nder axial compression is investigated. The analysis is based on nonli near kinematic relations and nonlinear rate-dependent unified constitu tive equations. Bodner-Partom's model is employed to represent the the rmoelastoviscoplastic material behavior. The material model does not s eparate the inelastic deformation into time-dependent (creep) and time -independent (plastic) deformations. It can cover elastic and inelasti c material behavior, and temperature effects simultaneously. A finite- element approach which with a two-phase solution scheme for the unifie d constitutive equations is employed to predict the inelastic buckling behavior of the structure. Numerical examples are given to demonstrat e the change of critical load, deformation mode, and the load-carrying capability in the postbuckling stage. The effects of several paramete rs, which include temperature, small initial imperfections, and the th ickness of the shell are assessed. The creep buckling is also studied as an example of the time-dependent deformation.