Determination of the Constants of Chaboche model at various strain rates

Many engineering components and structures may undergo cyclic loadings. Different models for predicting material behavior in cyclic loading has been suggested. Chaboche plasticity model is one of the most important models. The constants of this model are obtained in this work. The Chaboche model does not take any account of strain rate. In this paper, the theory of small strain has been considered for the analysis of strain tensor elastic and plastic parts. The constants have been obtained by a combined experimental/optimization technique. Two groups of tests including quasi-static and dynamic tests have been carried out in this study. The results obtained from quasistatic tests are used for calculating the coefficients of the Chaboche material model through genetic algorithm. The results of dynamic tests are used for identification of the constants using the neural network. The results show a remarkable agreement between the experiments, artificial neural network and genetic algorithm.

Keywords:

Strain Rate , Cyclic Plasticity , Neural Network , Optimization