Elastic-plastic large deformation static and dynamic analysis

Abstract

The problem of formulating and numerically implementing finite element elastic-plastic large deformation analysis is considered. In general, formulations can use different kinematic descriptions and assumptions in the material law, and analysis results can vary by a large amount. In this paper, starting from continuum mechanics principles, two consistent formulations for elastic-plastic large deformation analysis are presented in which either the initial configuration or the current configuration is used for the description of static and kinematic variables. The differences between the formulations are clearly identified and it is established that, depending on the elastic-plastic material description, identical numerical results can be obtained. If, in practice, certain constitutive transformations are not included, the differences in the analysis results are relatively small in large displacement but small strain problems. The formulations have been implemented and representative sample analyses of large deformation response of beams and shells are presented.