Modeling of textural anisotropy in granular materials with stochastic micro-polar hypoplasticity

Abstract

The paper deals with a numerical analysis of the effect of textural anisotropy on the behaviour of cohesionless granular materials with consideration of shear localization. For a simulation of the mechanical behavior of a granular material during a monotonic deformation path, an isotropic micropolar hypoplastic constitutive model was used. To describe textural effects, spatially correlated random fields of the initial void ratio were subject to rotation against the horizontal axis. The 2D random fields were generated using a conditional rejection method. The results were compared with those obtained with an anisotropic micro-polar constitutive model for an uniform distribution of the initial void ratio. The calculations were carried out with a dense granular specimen during plane strain compression under constant lateral pressure.Key words: finite element method, granular material, micro-polar hypoplasticity, random field, shear zone, textural anisotropy A c c e p t e d m a n u s c r i p t 2

A Local Constitutive Model with Anisotropy for Various Homogeneous 2D Biaxial Deformation Modes

“…(18), and especially the non-linearity of the second, see Section 4.2.6, can be seen as similar to the two terms in hypoplastic type theories (see Eq. (9) in [30] and references therein or Eq. (1) in [33,34], where Granular Solid Hydrodynamics (GSH) is concerned).…”

Non‐coaxiality and stress–dilatancy rule in granular materials: FE investigation within micro‐polar hypoplasticity

“…In this case, the range of a significant correlation was approximately 20 mm. Finally, one calculation was performed with the random field withē 0 = 0.62, x1 = 1, x2 = 1 and s e 0 = 0.05 rotated by the angle = 45 • against the horizontal axis x 1 to simulate the grain orientation with respect to the direction of sedimentation [26].…”

FE-calculations of stress distribution under prismatic and conical sandpiles within hypoplasticity

“…A characteristic length can be introduced into hypoplasticity by means of the micropolar, non-local and second-gradient theory. In this paper, a micro-polar theory is adopted [3], [4]. A micro-polar model makes use of rotations and couple stresses, which have clear physical meaning for granular materials.…”