ABSTRACT
The application of non-polar hypoplastic models is restricted to processes without strain localization because of a missing characteristic length. A characteristic length was captured by means of a polar theory (Tejchman & Gudehus, 2001; Tejchman, 2004). It can be also taken into account within hypoplasticity by means of a non-local continuum model (Tejchman, 2004) or a second gradient theory (Tejchman, 2004).A comparison of the different concepts shows, however, that for modeling of granular materials, the physical motivation of a polar continuum lies in its nature since it takes into account the influence of particle rotations and couple stresses which are observed during shearing but remain negligible during homogeneous deformation.
