Statistical properties of shear deformation of granular media and analogies with natural seismic processes

TL;DR

This study investigates shear deformation in granular media, revealing statistical laws similar to earthquakes, and explores how external perturbations can influence deformation and seismic-like activity.

Contribution

It demonstrates the statistical similarity between shear deformation in granular media and natural seismic processes, and develops methods to control deformation using external signals.

Findings

Deformation is intermittent and emits acoustic signals following seismic laws.

Weak periodic signals can reduce critical events at specific frequencies.

An algorithm was created to decrease stresses via external perturbations.

Abstract

In this paper, the process of shear deformation of the medium formed by the cubic grains is investigated experimentally. It is demonstrated that the deformation process is intermittent and accompanied by the radiation of acoustic perturbations. These perturbations obey statistical laws that are inherent in natural seismic processes: the frequency-energy scaling relation (the Gutenberg-Richter law) and the generalized Omori law for temporal decay of aftershocks. The weak perturbations influence on the process of shear deformation is studied for the mono-dispersed medium. During the granular medium stimulation by weak periodic signals, the existence of a critical frequency providing the smallest number of critical events in the granular medium is identified. We also developed the algorithm providing smaller stresses inside the granular massif by means of external perturbations during shear deformation. Taking into account the statistical similarity between shear and seismic processes, these results open prospects for the ability to affect the natural seismic processes.