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arXiv · 0710.5160

Onset of mechanical stability in random packings of frictional spheres

Melissa Jerkins·Matthias Schröter·Harry L. Swinney·Tim J. Senden·Mohammad Saadatfar·Tomaso Aste
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Abstract

Using sedimentation to obtain precisely controlled packings of noncohesive spheres, we find that the volume fraction $ϕ_{\rm RLP}$ of the loosest mechanically stable packing is in an operational sense well defined by a limit process. This random loose packing volume fraction decreases with decreasing pressure $p$ and increasing interparticle friction coefficient $μ$. Using X-ray tomography to correct for a container boundary effect that depends on particle size, we find for rough particles in the limit $p \to 0$ a new lower bound, $ϕ_{\rm RLP} = 0.550 \pm 0.001$.

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Melissa Jerkins, Matthias Schröter, Harry L. Swinney, Tim J. Senden, Mohammad Saadatfar, Tomaso Aste. 2008-07-03. Onset of mechanical stability in random packings of frictional spheres. https://doi.org/10.1103/physrevlett.101.018301

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