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Force heterogeneities in particle assemblies: from order to disorder
1Department of Physics, Southern Illinois University, Carbondale, Illinois 62901, USA. lsilbert@physics.siu.edu
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 7, 2007
Summary
Structural disorder significantly alters contact forces in granular materials. Increasing defects changes force distributions, impacting pressure and frequencies, relevant to jamming phenomena.
Area of Science:
- Physics
- Materials Science
- Computational Science
Background:
- Granular materials exhibit complex behaviors influenced by structural disorder.
- Understanding contact force distributions is crucial for predicting material properties.
- Jamming phenomena in glassy and granular systems remain an active research area.
Purpose of the Study:
- To systematically investigate the effect of increasing structural disorder on contact force distributions in 3D particle assemblies.
- To compare different protocols for introducing disorder and quantify its impact.
- To explore the relationship between disorder, pressure, and normal mode frequencies.
Main Methods:
- Computer simulations of model granular packings.
- Systematic introduction of defects into a face-centered-cubic (FCC) lattice.
- Analysis of coordination number and three-particle contact angle distributions.
- Examination of normal contact force distributions P(f).
Main Results:
- Increasing structural disorder causes dramatic qualitative changes in normal contact force distributions.
- In weakly disordered regimes, pressure and lowest normal mode frequency scale linearly with coordination number.
- The study compared three distinct protocols for imposing disorder.
Conclusions:
- Structural disorder is a key factor governing contact forces in granular assemblies.
- The findings provide insights into jamming phenomena in disordered systems.
- The research establishes a quantitative link between structural disorder and mechanical properties.
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