A.r. Khoei, S. Yadegari, M. Anahid,
Volume 4, Issue 3 (September 2006)
Abstract
In this paper, a higher order continuum model is presented based on the Cosserat
continuum theory in 3D numerical simulation of shear band localization. As the classical
continuum models suffer from the pathological mesh-dependence in strain softening models, the
governing equations are regularized by adding the rotational degrees-of-freedom to conventional
degrees-of-freedom. The fundamental relations in three-dimensional Cosserat continuum are
presented and the internal length parameters are introduced in the elasto-plastic constitutive matrix
to control the shear bandwidth. Finally, the efficiency of proposed model and computational
algorithm is demonstrated by a 3D strip in tensile. A comparison is performed between the classical
and Cosserat theories and the effect of internal length parameter is demonstrated. Clearly, a finite
shear bandwidth is achieved and the load-displacement curves are uniformly converged upon
different mesh sizes.