Experiences with viscoplastic constitutive equations in finite element shell analysis

In the paper problems of application of the viscoplastic constitutive models in the shell finite element analysis are considered. At the beginning the short history of models development is presented. Then, the most important assumptions, which must be made to obtain the viscoplastic model and apply it within the FEM shell analysis, are discussed. After the consist presentation of three selected models based on experiments, the problems of the constitutive models’ parameters identification are presented. The special terms for viscoplastic analysis which must be introduced into the finite element approach are shown. Problems of numerical stability of calculations are also discussed. Finally, some examples of the geometrically nonlinear dynamic analysis illustrate the paper.