A comparison between the volumetrically elastic and deviatorically rigid-plastic FEM and the penalty rigid-plastic FEM

Abstract

The volumetrically elastic and deviatorically rigid-plastic finite element method (FEM) is a different method from the conventional penalty rigid-plastic FEM, and has some merits in comparison with the penalty rigid-plastic FEM. To secure numerical evidence on the difference between the two kinds of methods and to show the merits of the volumetrically elastic and deviatorically rigid-plastic FEM, this paper makes analyses of the upsetting of an aluminium alloy column by the two kinds of methods. Then, normal solutions are compared with deviant solutions that are given by relaxing convergence criteria of the iterative solution in a calculated step by the two kinds of methods, respectively. In this way, it can be clarified that the errors of the step virtually disappear, and that the calculated results are largely corrected in the next step and the later steps for the volumetrically elastic and deviatorically rigid-plastic finite element analysis. Copyright © 1999 John Wiley & Sons, Ltd.