Jammed frictional tetrahedra are hyperstatic
Abstract
We prepare packings of frictional tetrahedra with volume fractions {\phi} ranging from 0.469 to 0.622 using three different experimental protocols under isobaric conditions. Analysis via X-ray micro-tomography reveals that the contact number Z grows with {\phi}, but does depend on the preparation protocol. While there exist four different types of contacts in tetrahedra packings, our analysis shows that the edge-to-face contacts contribute about 50% of the total increase in Z. The number of constraints per particle C increases also with {\phi} and even the loosest packings are strongly hyperstatic i.e. mechanically over-determined with C approximately twice the degrees of freedom each particle possesses.
Cite
@article{arxiv.1202.6272,
title = {Jammed frictional tetrahedra are hyperstatic},
author = {Max Neudecker and Stephan Ulrich and Stephan Herminghaus and Matthias Schröter},
journal= {arXiv preprint arXiv:1202.6272},
year = {2015}
}
Comments
5 pages, 5 figures Includes supplement: 10 pages, 8 figures