Micro-mechanics of fabric and failure in granular materials

Abstract

The paper addresses the underlying source of two forms of induced anisotropy in granular materials: contact orientation anisotropy and contact force anisotropy. A rational, mathematical structure is reviewed for the manner in which fabric anisotropy emerges and evolves during loading. Fabric is expressed as an orientation density, and transport phenomena such as convection, contact generation, and diffusion control the rate of fabric evolution during loading. The paper proposes specific measurable forms for all terms, based upon the micro-mechanics of particle interactions. Discrete element (DEM) simulations are used to verify and quantify these terms, so that the theory can be applied to general loading conditions. The DEM simulations are of densely packed durable spheres, and the emphasis is on soil behavior at large strains, specifically on fabric and strength at the critical state. Once the theory has been developed and quantified, it is applied to predict the effect of the intermediate principal stress on strength.

References in corpus (3)

• Contact rolling and deformation in granular media
• Stability, bifurcation, and softening in discrete systems: A conceptual approach for granular materials
• Are granular materials simple? An experimental study of strain gradient effects and localization

Cited by in corpus (5)

• Stress-induced anisotropy in granular materials: fabric, stiffness, and permeability
• Implementation of the Jager contact model for discrete element simulations
• Contact transience during slow loading of dense granular materials
• Dense granular flow at the critical state: maximum entropy and topological disorder
• Thermomechanics of dense granular materials: a particle-scale perspective