Bounds on the shear load of cohesionless granular matter
نویسندگان
چکیده
We characterize the force state of shear-loaded granular matter by relating the macroscopic stress to statistical properties of the force network. The purely repulsive nature of the interaction between grains naturally provides an upper bound for the sustainable shear stress, which we analyze using an optimization procedure inspired by the so-called force network ensemble. We establish a relation between the maximum possible shear resistance and the friction coefficient between individual grains, and find that anisotropies of the contact network (or the fabric tensor) only have a subdominant effect. These results can be considered the hyperstatic limit of the force network ensemble and we discuss possible implications for real systems. Finally, we argue how force anisotropies can be related quantitatively to experimental measurements of the effective elastic constants. PACS numbers: 45.70.Cc, 05.40.-a, 46.65.+g
منابع مشابه
The Limiting Ideal Theory for Shear-index Cohesionless Granular Materials
To model cohesionless granular flow using continuum theory, the usual approach is to assume the cohesionless Coulomb-Mohr yield condition. However, this yield condition assumes that the angle of internal friction is constant, when according to experimental evidence for most powders the angle of internal friction is not constant along the yield locus, but decreases for decreasing normal stress c...
متن کاملUsing infrared thermography to study hydrostatic stress networks in granular materials.
The macroscopic mechanical behaviour of granular materials is governed by microscopic features at the particle scale. Photoelasticimetry is a powerful method for measuring shear stresses in particles made from birefringent materials. As a complementary method, we here identify the hydrostatic stress networks through thermoelastic stress analysis using infrared thermographic measurements. Experi...
متن کاملConstitutive relations for cohesionless frictional granular materials
Based on the micro-mechanical model recently developed by Nemat-Nasser S. (J. Mech. Phys. Solids 48 (2000) 1541), a three-dimensional continuum mechanics model is presented for the deformation of granular materials which carry the applied load through frictional contacts. The model incorporates the anisotropy (or fabric) which develops as a frictional granular mass is deformed in shear, and inc...
متن کاملAnnular shear of cohesionless granular materials: from the inertial to quasistatic regime.
Using discrete simulations, we investigate the behavior of a model granular material within an annular shear cell. Specifically, two-dimensional assemblies of disks are placed between two circular walls, the inner one rotating with prescribed angular velocity, while the outer one may expand or shrink and maintains a constant radial pressure. Focusing on steady state flows, we delineate in param...
متن کاملInvestigations of Shear Localization in Granular Bodies within an Anisotropic Micro-Polar Hypoplasticity
The paper focuses on the numerical analysis of the effect of texturial anisotropy on shear localization in cohesionless granular materials. For simulation of the mechanical behavior of a granular material during a monotonous deformation path, a hypoplastic constitutive model was used. To take into account a characteristic length of micro-structure, the constitutive model was extended by micro-p...
متن کامل