Modeling the viscoplastic transient dynamic process

A hollow viscoelastic right circular cylinder subjected to a time-dependent load is considered. The cylinder is with finite dimensions. A transient load acts upon the inner surface of the cylinder, whereas no loads are applied to outer surfaces. The end surfaces of the cylinder are restrained to move along the cylinder axis. The viscoelastic behaviour of the material is modelled using Boltzmann – Volterra equations. A yield criterion is implemented in the numerical analyses. By assumption, upon reaching the yield surface, the linear viscoelastic model switches to a plastic constitutive relation. The transient dynamic behaviour of the material is simulated for different intensities of the applied load and model parameters.