Force distributions in three dimensional compressible granular packs

TL;DR

This study experimentally examines how grain deformation affects the distribution of contact forces in 3D compressible granular packs, revealing that deformation influences the shape and tail behavior of the force distribution.

Contribution

It provides new insights into the impact of grain deformation on force distributions in granular materials through experimental analysis.

Findings

Small deformation results in a peak below the mean force with an exponential tail.

Increased deformation enhances the peak at the mean force.

The exponential tail becomes steeper with more deformation.

Abstract

We present an experimental investigation of the probability distribution of normal contact forces, $P(F)$, at the bottom boundary of static three dimensional packings of compressible granular materials. We find that the degree of deformation of individual grains plays a large role in determining the form of this distribution. For small amounts of deformation we find a small peak in $P(F)$ below the mean force with an exponential tail for forces larger than the mean force. As the degree of deformation is increased the peak at the mean force grows in height and the slope of the exponential tail increases.