Avalanche contribution to shear modulus of granular materials
Michio Otsuki1, Hisao Hayakawa2
1Department of Materials Science, Shimane University, Matsue 690-8504, Japan.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|November 7, 2014
Summary
This study numerically investigates the shear modulus of granular materials near jamming. The shear modulus G follows a scaling law, interpolating between two key behaviors related to grain volume fraction and shear amplitude.
Area of Science:
- Physics
- Materials Science
- Rheology
Background:
- Granular materials exhibit complex behavior near the jamming transition.
- Understanding the shear modulus is crucial for predicting material response.
Purpose of the Study:
- To numerically investigate the shear modulus of frictionless granular materials.
- To explore the scaling laws governing shear modulus near the jamming transition under oscillatory shear.
Main Methods:
- Numerical simulations were employed.
- A linear spring model for inter-grain elastic interactions was used.
- Oscillatory shear was applied to the granular system.
Main Results:
- The shear modulus (G) was found to satisfy a scaling law.
- This law interpolates between G∼(ϕ-ϕJ)(1/2) and G∼γ0(-1/2)(ϕ-ϕJ).
- The relation between shear modulus and (ϕ-ϕJ) is explained by slip avalanches.
Conclusions:
- A unified scaling law describes the shear modulus of granular materials near jamming.
- Slip avalanches play a key role in the linear relationship observed.
- The findings provide insights into the mechanical properties of granular systems.
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