Generalized standard media and variational principles in classical and finite strain elastoplasticity

Abstract

This paper uses the concept of generalized standard media in order to develop a rational theory of small and finite strain elastoplasticity. Invariance requirements for yield function and flow rule are derived especially for the finite strain case. It is shown that isotropic and kinematic hardening can be incorporated into the general concept in a natural way. Finally the thermodynamic background is discussed and used to derive a novel unified variational principle.