An objective incremental formulation for the solution of anisotropic elastoplastic problems at finite strain

This paper presents an objective formulation for the anisotropic elastic-plastic problems at large strain plasticity. The constitutive equations are written in a rotating frame. The multiplicative decomposition of the deformation gradient is adopted and the formulation is hyperelastic based. Since no stress rates are present and the incremental constitutive law was formulated in a rotating frame, the formulation is numerically objective in the time integration. Explicit algorithm was proposed and has been optimized with regard to stability and accuracy. The incremental law was integrated in fast Lagrangian analysis of continua (FLAC) method to model anisotropic elastic-plastic problems at finite strain. Structural tests are carried out for isotropic and orthotropic materials. Copyright (C) 2001 John Wiley & Sons, Ltd.