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arXiv · 2604.20102

Unjamming in a 3D Granular System: The Micromechanical Role of Friction in Force Distributions and Rheological Properties

Vicente Salinas·Héctor Alarcón·Eduardo Rojas·Pablo Gutiérrez·Gustavo Castillo
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Abstract

In this work, we investigate the unjamming transition in a three-dimensional granular system composed of frictional spheres, in which the packing fraction is systematically reduced by random particle extractions. Using Discrete Element Method (DEM) simulations, we analyze the evolution of key micro-mechanical quantities, such as the interparticle forces, the coordination number and the overall packing density as a function of the interparticle friction coefficient. Our results reveal friction-dependent relationships on structural as well as mechanical observables, and exhibit trends that are qualitatively consistent with observations reported in dense granular systems. These trends persist despite the very different driving mechanism considered here. This paper is part of the thematic issue \emph{``Sand, silos and asteroids: clustering challenges in granular materials research''}.

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Vicente Salinas, Héctor Alarcón, Eduardo Rojas, Pablo Gutiérrez, Gustavo Castillo. 2026-04-22. Unjamming in a 3D Granular System: The Micromechanical Role of Friction in Force Distributions and Rheological Properties. https://arxiv.org/abs/2604.20102

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