抄録
The present paper proposes mixed variational theorems of classical rate-independent elastoplasticity at finite strain based on the energy equation of Toupin, which takes into account the effects of nonsymmetric stress. The proposed variational principle can easily incorporate the internal work related to angular momentum balance, which has not been treated precisely in the previous works. Attention is also focused on the consistent and rational derivations of variational theorems based on the total Lagrangian formulation in terms of the nonsymmetric first Piola-Kirchhoff stress as well as the symmetric second Piola-Kirchhoff stress. Also discussed and clarified is the explicit derivation of complementary energy for elastoplasticity in rate form to be applicable for the finite element analysis.
