Evolution of granular materials under isochoric cyclic simple shearing.
Ming Yang1, Mahdi Taiebat1, Patrick Mutabaruka2
1Department of Civil Engineering, University of British Columbia, Vancouver BC V6T1L7, Canada.
Physical Review. E
|April 17, 2021
Summary
Granular materials under cyclic shearing liquefy, exhibiting jamming-unjamming cycles. This involves network collapse, strength loss, and irreversible strain accumulation, crucial for soil and suspension behavior.
Area of Science:
- Geotechnical Engineering
- Materials Science
- Physics
Background:
- Granular materials exhibit complex behaviors under cyclic loading, including liquefaction.
- Understanding microstructure evolution is key to predicting macroscopic responses.
Purpose of the Study:
- To analyze the microstructure of granular materials during isochoric cyclic shearing.
- To investigate the jamming-unjamming transition and its relation to network properties.
Main Methods:
- 3D particle dynamics simulations.
- Analysis of particle connectivity, force transmission, and network anisotropies.
Main Results:
- Simulations reproduce key features of granular cyclic behavior and liquefaction.
- Liquefaction onset correlates with force network collapse and coordination number drop.
- Jamming transition occurs at a critical coordination number, independent of initial conditions.
Conclusions:
- The study elucidates the microstructural mechanisms driving liquefaction in granular materials.
- Findings offer insights into soil liquefaction and dense suspension rheology.
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