Scaling Theory of Giant Frictional Slips in Decompressed Granular Media

TL;DR

This paper develops a scaling theory to explain giant frictional slips in decompressed granular media, revealing that the amplitude of slippage diverges with system size, indicating potential for large slip events.

Contribution

It introduces a theoretical scaling framework with computable exponents for understanding frictional slips in decompressed granular systems, linking force distributions to instability.

Findings

Amplitude diverges in the thermodynamic limit

Giant slip events are possible in large systems

Force distributions are highly correlated due to Coulomb condition

Abstract

When compressed frictional granular media are decompressed, generically a fragile configuration is created at low pressures. Typically this is accompanied by a giant frictional slippage as the fragile state collapses. We show that this instability is understood in terms of a scaling theory with theoretically computable amplitudes and exponents. The amplitude diverges in the thermodynamic limit hinting to the possibility of huge frictional slip events in decompressed granular media. The physics of this slippage is discussed in terms of the probability distribution functions of the tangential and normal forces on the grains which are highly correlated due to the Coulomb condition.