Jamming of 3D Prolate Granular Materials

K. Desmond; Scott V. Franklin

doi:10.1103/physreve.73.031306

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arXiv · cond-mat/0608674

Jamming of 3D Prolate Granular Materials

K. Desmond·Scott V. Franklin

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Abstract

We have found that the ability of long thin rods to jam into a solid-like state in response to a local perturbation depends upon both the particle aspect ratio and the container size. The dynamic phase diagram in this parameter space reveals a broad transition region separating granular stick-slip and solid-like behavior. In this transition region the pile displays both solid and stick-slip behavior. We measure the force on a small object pulled through the pile, and find the fluctuation spectra to have power law tails with an exponent characteristic of the region. The exponent varies from $β=-2$ in the stick-slip region to $β=-1$ in the solid region. These values reflect the different origins -- granular rearrangements vs. dry friction -- of the fluctuations. Finally, the packing fraction shows only a slight dependence on container size, but depends on aspect ratio in a manner predicted by a mean field theory and implies an aspect-ratio independent contact number of $ = 5.25 \pm 0.03$.

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K. Desmond, Scott V. Franklin. 2006-08-30. Jamming of 3D Prolate Granular Materials. https://doi.org/10.1103/physreve.73.031306

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