Authors: Stefan Luding Fernando AlonsoMarroquín
Publish Date: 2011/01/18
Volume: 13, Issue: 2, Pages: 109-119
Abstract
Dry granular materials in a splitbottom ring shear cell geometry show wide shear bands under slow quasistatic large deformation This system is studied in the presence of contact adhesion using the discrete element method DEM Several continuum fields like the density the deformation gradient and the stress tensor are computed locally and are analyzed with the goal to formulate objective constitutive relations for the flow behavior of cohesive powders From a single simulation only by applying time and local spaceaveraging and focusing on the regions of the system that experienced considerable deformations the criticalstate yield stress termination locus can be obtained It is close to linear for noncohesive granular materials and nonlinear with peculiar pressure dependence for adhesive powders—due to the nonlinear dependence of the contact adhesion on the confining forces The contact model is simplified and possibly will need refinements and additional effects in order to resemble realistic powders However the promising method of how to obtain a criticalstate yield stress from a single numerical test of one material is generally applicable and waits for calibration and validationThis article is published under an open access license Please check the Copyright Information section for details of this license and what reuse is permitted If your intended use exceeds what is permitted by the license or if you are unable to locate the licence and reuse information please contact the Rights and Permissions team
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