A study of the constitutive equations of the flow of cohesionless granular materials at large rates of deformation and low stress levels is presented. The interstitial fluid effects are assumed negligible and the particles approximately incompressible. / Dimensional arguments and experimental observations suggest that two different regimes of flow may occur. At low rates of deformation, the Coulomb friction gives rise to stresses that are rate independent (of the plastic type). At large rates of deformation, momentum transfer arises from particles collisions and the resulting stresses become rate dependent (of the viscous type). A continuum model that includes both types of behaviour is proposed. The equilibrium part of the stress tensor satisfies the Mohr-Coulomb yield criterion and a non-coaxial flow rule. The viscous part is assumed to have a form corresponding to an isotropic Reiner-Rivlin fluid. / Experiments of simple shear flow flow in an annular shear cell were performed on several types of dry granular materials. The purpose of the tests was to obtain the information needed for the continuum description of the material behaviour. At lower solids concentrations and high shear rates where the inter-particle collisions are dominant, both shear and normal stresses were proportional to the square of the shear rate. At higher concentrations and lower shear rates, Coulomb friction between particles became increasingly important and the stresses were proportional to the shear rate raised to a power less than two. All tests showed a strong dependence upon solids concentration.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.68585 |
| Date | January 1981 |
| Creators | Sayed, Mohammed. |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Civil Engineering and Applied Mechanics) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 000127587, proquestno: AAINK52115, Theses scanned by UMI/ProQuest. |
Page generated in 0.0022 seconds