H-adaptive mesh refinement for shear band localization in elasto-plasticity Cosserat continuum

In this paper, an h-adaptive mesh refinement is presented based on the gradient of deformation in the modeling of localization due to material instability. As the classical continuum models suffer from pathological mesh dependence in the strain-softening models, the governing equations are regularized by adding rotational degrees-of-freedom to the conventional degrees-of-freedom. Adaptive strategy using element elongation is applied to compute the distribution of required element size using the estimated error distribution. Once the new element size and its alignment have been indicated, an automated procedure is used to construct the mesh according to a predetermined size and elongation distribution. Finally, the efficiency of the proposed model and computational algorithms is demonstrated by several numerical examples. Clearly, a finite shear bandwidth is achieved and the load-displacement curves is uniformly converged upon mesh refinement. It is shown that the h-adaptive remeshing using Cosserat continuum can be effectively used in the modeling of localization phenomena.