Error-correcting merit of the volumetrically elastic and deviatorically rigid-plastic finite-element method

Abstract

The volumetrically elastic and deviatorically rigid-plastic finite-element method is a method placed between the rigid-plastic finite-element method and the elastic-plastic finite-element method, and has the merit of automatic error-correcting by comparing with the conventional rigid-plastic finite-element methods. To secure numerical evidence on this merit, this paper makes analyses of the upsetting of an aluminium alloy column by this method and by the conventional Lagrange multiplier rigid-plastic finite-element method. Then, normal solutions are compared with deviant solutions that are given by relaxing the 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 do not remain, 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.