Discontinuous rigidity transition associated with shear jamming in granular simulations
Varghese Babu1, H A Vinutha2, Dapeng Bi3
1Theoretical Sciences Unit and School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Rachenahalli Lake Road, Bengaluru 560064, India. varghese@jncasr.ac.in.
Soft Matter
|October 13, 2023
Summary
Shear jamming in disk packings shows a discontinuous rigidity transition, unifying frictionless and frictional systems. This transition involves the sudden formation of rigid clusters, regardless of friction, in the quasi-static limit.
Area of Science:
- Soft Matter Physics
- Materials Science
- Granular Mechanics
Background:
- Shear jamming is a phenomenon where granular materials transition from a fluid-like to a solid-like state under shear stress.
- Understanding the nature of this transition (continuous vs. discontinuous) is crucial for predicting material behavior.
Purpose of the Study:
- To investigate the rigidity transition during shear jamming in both frictionless and frictional disk packings.
- To determine if the transition is continuous or discontinuous across different frictional conditions and shear rates.
Main Methods:
- Simulations of frictionless and frictional disk packings under quasi-static shear and low shear rates.
- Analysis of the emergence and spanning of rigid clusters to identify the rigidity transition point.
Main Results:
- Frictionless disks exhibit a discontinuous rigidity transition with instantaneous formation of system-spanning rigid clusters.
- Frictional systems show a continuous transition at finite shear rates, which sharpens at lower rates.
- In the quasi-static limit, the transition for frictional systems is also discontinuous.
Conclusions:
- The rigidity transition associated with shear jamming is fundamentally discontinuous, even in the presence of friction.
- Discontinuous shear jamming is a unifying feature across different particle types and jamming scenarios.
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