Prediction of structural ratcheting by various models

Abstract

The present study aims to evaluate the capabilities of a class of models that take into account nonlinear isotropic and kinematic hardening. The purpose is to predict the behaviour of a ''Bi-tube'' structure when submitted to a cyclic thermo-mechanical loading. The first part consists of an overview of the methods of describing different kinematic hardening variables. In the second part, the studied structure and the results of numerical simulation of the models used are presented, with an emphasis on the sensitivity of the analysis with regard to the choice of the element type, using a FE software 'Code-Aster', developed by Electricité de France. This study constitutes a first step in the validation of the models of cyclic behaviour with respect to tests on structures, limited in this first case to Bitube structure. The comparison between numerical predictions and the experimental results demonstrates that the model of Taheri seems to be the best adapted to the study of 'Bi-tube' structures because it leads to stabilisation around 1%, which is comparable to the experimental results.