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Granular solids, liquids, and gases
Granular materials are ubiquitous in the world around us. They have properties that are different from those commonly associated with either solids, liquids, or gases. In this review the authorsExpand
Contact force measurements and stress-induced anisotropy in granular materials
Measurements of the normal and tangential grain-scale forces inside a two-dimensional system of photoelastic disks that are subject to pure shear and isotropic compression show the underlying differences between these two stress states. Expand
Sands, Powders, and Grains: An Introduction to the Physics of Granular Materials
1. Introduction.- 1.1 Some Orders of Magnitude Defining the Problem.- 1.2 Economic Implications and Industrial Problems.- 1.2.1 Industrial Processing of Granulars.- Construction Materials.-Expand
Stress Fluctuations in a 2D Granular Couette Experiment: A Continuous Transition
Granular systems have captured much recent interest be-cause of their rich phenomenology and important applica-tions [1]. Even in the absence of strong spatial disorder ofthe grains, static arraysExpand
Jamming by shear
It is shown that jamming of frictional, disk-shaped grains can be induced by the application of shear stress at densities lower than the critical value, at which isotropic (shear-free) jamming occurs. Expand
Memories in sand: experimental tests of construction history on stress distributions under sandpiles.
It is shown that the stress profiles scale linearly with the pile height, and on wedge-shaped piles, the effects of construction history on static stress distributions are similar but weaker. Expand
Logarithmic rate dependence of force networks in sheared granular materials
This work investigates the rate dependence of stress in a slowly sheared two-dimensional system of photoelastic disks, in which it is able to determine forces on the granular scale and finds that the mean (time-averaged) stress displays a logarithmic dependence on the shear rate for plastic (irreversible) deformations. Expand
Predictability and granular materials
Abstract Granular materials present a number of challenges to predictability. The classical description of a dense granular material is based on Coulomb friction. For a static array of grains, theExpand
Self-diffusion in dense granular shear flows.
  • B. Utter, R. Behringer
  • Physics, Medicine
  • Physical review. E, Statistical, nonlinear, and…
  • 1 September 2003
Experimental results on diffusivity in dense, granular shear flows in a two-dimensional Couette geometry find that self-diffusivities D are proportional to the local shear rate gamma; with diffusivities along the direction of the mean flow approximately twice as large as those in the perpendicular direction. Expand