A new integration algorithm for the von-Mises elasto-plastic model

We introduce a new numerical time integration scheme, in the framework of associative von-Mises plasticity with linear kinematic and isotropic hardening. The new procedure is based on the model reformulation in terms of an augmented stress tensor and on the adoption of an integration factor; the integration of the model makes use of exponential maps. A consistent number of numerical tests enlighten the superior behaviour of the new exponential-based technique, by means of comparison with classical return map algorithms based either on backward Euler or generalized midpoint integration rules.