Dissipation in quasistatically sheared wet and dry sand under confinement
J E Fiscina1, M Pakpour, A Fall
1Experimental Physics, Saarland University, D-66123, Saarbrücken, Germany. j.fiscina@mx.uni-saarland.de
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 26, 2012
Summary
Dry sand deforms more easily and dissipates more energy than wet sand, contrary to expectations based on shear modulus. This study reveals key differences in the rheological behavior of granular materials with varying liquid content.
Area of Science:
- Geotechnical Engineering
- Materials Science
- Physics of Granular Media
Background:
- Dry sand typically exhibits a lower shear modulus, suggesting easier deformation.
- Understanding granular material behavior under shear is crucial for various engineering applications.
Purpose of the Study:
- To investigate the stress-strain behavior of sand with and without liquid content.
- To compare the deformation resistance and energy dissipation of dry versus wet sand under shear flow.
Main Methods:
- Utilized a novel technique to push sand quasistatically through a tube, enforcing a parabolic flow profile to minimize avalanches and shear localization.
- Performed large-amplitude oscillatory shear measurements using a rotational rheometer.
Main Results:
- Partially saturated (wet) sand showed significantly lower resistance to deformation compared to dry sand.
- Dry sand dissipated more energy during flow than wet sand.
- The observed phenomena were consistent across both steady and oscillatory shear conditions.
Conclusions:
- The presence of small amounts of liquid dramatically alters the rheological properties of sand, reducing deformation resistance.
- Contrary to intuition based on shear modulus, wet sand flows more readily than dry sand.
- The findings are robust and applicable to different flow regimes in granular materials.
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