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Updated: Jul 15, 2026
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Ensemble Force Spectroscopy by Shear Forces
Published on: July 26, 2022
Universal anisotropy in force networks under shear.
Srdjan Ostojic1, Thijs J H Vlugt, Bernard Nienhuis
1Institute for Theoretical Physics, Universiteit van Amsterdam, Valckenierstraat 65, 1018 XE Amsterdam, The Netherlands.
Summary
Applied shear stress does not alter universal scaling properties in static packings. Instead, it creates distinct length scales related to force network anisotropy, independent of contact network details.
Area of Science:
- Physics
- Materials Science
- Statistical Mechanics
Background:
- Understanding the mechanical behavior of granular materials and disordered systems is crucial.
- Force networks govern the macroscopic properties of static granular packings.
Purpose of the Study:
- To investigate how applied shear stress influences scaling properties of patterns in 2D static packings.
- To determine the relationship between shear stress, length scales, and force network anisotropy.
Main Methods:
- Generation of 2D static packings using the force network ensemble.
- Anisotropic finite-size-scaling analysis as a function of applied shear stress.
Main Results:
- Applied shear stress does not change the universal scaling properties of the patterns.
- Shear stress induces different length scales along principal stress directions.
- The ratio of these length scales quantifies force network anisotropy.
Conclusions:
- The anisotropy of force networks, quantified by length scale ratios, is independent of the underlying contact network details.
- This finding contrasts with other properties like yield stress, suggesting a universal aspect of force network anisotropy.
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