Evolution of shear zones in granular materials
Balázs Szabó1, János Török2, Ellák Somfai1
1Institute for Solid State Physics and Optics, Wigner Research Center for Physics, Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest, Hungary.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|October 15, 2014
Summary
Particle shape significantly impacts shear zone evolution in granular flows. Irregular grains create narrower final shear zones compared to spherical beads, affecting material behavior under stress.
Area of Science:
- Geophysics
- Materials Science
- Physics
Background:
- Shear zones are critical in understanding granular material deformation.
- The influence of particle shape on shear zone evolution is not fully understood.
Purpose of the Study:
- To investigate the evolution of shear zones in quasistatic dry granular flows.
- To compare the effects of particle shape (spherical, irregular, elongated) on shear zone width.
Main Methods:
- Experimental and numerical simulations using split-bottom shear cells.
- Analysis of granular flows composed of beads, sand, and elongated particles.
Main Results:
- Shear zone width initially decreases significantly, with strain increasing with shape anisotropy.
- A subsequent slight increase in zone width is more pronounced for rod-like particles.
- Final shear zone width is smaller for irregular grains than for spherical beads.
Conclusions:
- Particle shape anisotropy and reorientation effects influence shear zone evolution and final width.
- Shear-induced changes in packing density are linked to zone width dynamics.
- Irregular particle shapes lead to denser packing and narrower shear zones.
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