The hierarchical properties of contact networks in granular packings

TL;DR

This paper investigates the hierarchical topological structure of contact networks in large, disordered granular packings of monosized spheres, revealing higher topological density compared to lattice packings.

Contribution

It introduces a topological map approach to analyze the hierarchical organization of contact networks in granular packings, highlighting differences from lattice arrangements.

Findings

Disordered sphere packings have higher topological density than lattice packings.

Hierarchical organization can be characterized by concentric shells from a given sphere.

The study provides insights into the structure of granular materials.

Abstract

The topological structure resulting from the network of contacts between grains (contact network) is studied for very large samples of disorderly-packed monosized spheres with densities ranging from 0.58 to 0.64. The hierarchical organization of such a structure is studied by means of a topological map which starts from a given sphere and moves outwards in concentric shells through the contact network. We find that the topological density of disordered sphere packing is larger than the topological density of equivalent lattice sphere packings.