Structure of plastically compacting granular packings

TL;DR

This study investigates how the internal structure of ductile granular packings evolves during compaction, revealing differences from hard particle systems and emphasizing the importance of compaction history.

Contribution

It provides experimental insights into the structural evolution of ductile granular packings during compaction, highlighting differences from hard particle systems and the significance of compaction history.

Findings

Radial distribution function peaks are reduced, broadened, and shifted in ductile grains.

Three-grain configurations differ between initial and final compaction stages.

Coordination number evolution depends on packing fraction and compaction history.

Abstract

The developing structure in systems of compacting ductile grains were studied experimentally in two and three dimensions. In both dimensions, the peaks of the radial distribution function were reduced, broadened, and shifted compared with those observed in hard disk- and sphere systems. The geometrical three--grain configurations contributing to the second peak in the radial distribution function showed few but interesting differences between the initial and final stages of the two dimensional compaction. The evolution of the average coordination number as function of packing fraction is compared with other experimental and numerical results from the literature. We conclude that compaction history is important for the evolution of the structure of compacting granular systems.