On the formulation of closest-point projection algorithms in elastoplasticity. Part I: The variational structure

Author (s): Armero, F. and Pérez-Foguet, A.
Journal: International Journal for Numerical Methods in Engineering

Volume: 53, Issue 2
Pages: 297 – 329
Date: 2002


We present in this paper the characterization of the variational structure behind
the discrete equations defining the closest-point projection approximation in
elastoplasticity. Rate-independent and viscoplastic formulations are considered
in the infinitesimal and the finite deformation range, the later in the context
of isotropic finite strain multiplicative plasticity. Primal variational principles
in terms of the stresses and stress-like hardening variables are presented first,
followed by the formulation of dual principles incorporating explicitly the plastic
multiplier. Augmented Lagrangian extensions are also presented allowing a complete
regularization of the problem in the constrained rate-independent limit. The variational
structure identified in this paper leads to the proper framework for the development
of new improved numerical algorithms for the integration of the local constitutive
equations of plasticity as it is undertaken in Part II of this work.



@article {2002-IJNME-AP,
author = {Armero, F. and P\'erez-Foguet, A.},
title = {On the formulation of closest-point projection algorithms in elastoplasticity—part I: The variational structure},
journal = {International Journal for Numerical Methods in Engineering},
volume = {53},
number = {2},
pages = {297--329},
doi = {10.1002/nme.278},
issn = {1097-0207},
year = {2002},