A framework for finite strain elastoplasticity based on maximum plastic dissipation and the multiplicative decomposition. Part II: Computational aspects

Computational aspects of the formulation of elastoplasticity proposed in Part I of this work, employing a multiplicative decomposition and based on the principle of maximum plastic dissipation, are examined in detail. In particular, the implementation of the proposed hyperelastic J2-flow theory is shown to reduce to a trivial modification of the classical radial return algorithm which is amenable to exact linearization. This results in a closed-form expression for the consistent elastoplastic tangent moduli. The algorithmic treatment of the general case is considered subsequently. It is emphasized that objective rates and incrementally objective algorithms play no role in the present approach. A number of numerical experiments are presented that illustrate the excellent performance of the proposed formulation.