Shear zones in granular media: three-dimensional contact dynamics simulation
Alexander Ries1, Dietrich E Wolf, Tamás Unger
1Department of Physics, University Duisburg-Essen, D-47048 Duisburg, Germany.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|February 1, 2008
Summary
This study simulates granular flow shear zones, finding that gravity does not affect wide shear zone formation. The critical state zone
Area of Science:
- Granular physics
- Rheology of granular materials
Background:
- Shear zones are fundamental to granular material deformation.
- Understanding granular flow properties is crucial for various industrial applications.
Purpose of the Study:
- To investigate the properties of shear zones in slow, 3D granular flow.
- To analyze the influence of gravity on shear zone formation and characteristics.
Main Methods:
- Simulation of a straight split-bottom shear cell.
- Analysis of stress and velocity fields during flow relaxation.
Main Results:
- Wide shear zones form consistently, irrespective of gravity.
- A functional form describing shear zone widening within the bulk was determined.
- The growth of the critical state region was identified as the cause of initial shear zone transients.
Conclusions:
- Gravity is not a determining factor for wide shear zone formation in this granular flow model.
- The development of the critical state region governs the initial transient behavior of shear zones.
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