Equation for the force experienced by a wall overflowed by a granular avalanche: experimental verification
Thierry Faug1, Paolo Caccamo, Benoit Chanut
1Cemagref, ETGR, FR-38402 Saint-Martin d'Hères, France. thierry.faug@cemagref.fr
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|December 21, 2011
Summary
This study quantifies the force of granular avalanches on walls using laboratory tests and a depth-averaged momentum model. The research provides a method to estimate avalanche forces, crucial for designing protective structures.
Area of Science:
- Geophysics
- Civil Engineering
- Physics of granular materials
Background:
- Granular avalanches pose significant risks, necessitating accurate force estimations on barriers.
- Previous models often simplify the complex dynamics of avalanche-wall interactions.
Purpose of the Study:
- To measure and model the force exerted by a granular avalanche overflowing a wall.
- To validate a depth-averaged momentum conservation model against experimental data.
Main Methods:
- Laboratory experiments measuring flow properties (thickness, velocity) and wall forces.
- Utilizing a previously developed 2D discrete numerical simulation model.
- Comparing model predictions with experimental results across various slopes.
Main Results:
- Successful calibration of the depth-averaged momentum model against experimental data.
- Demonstrated the model's ability to estimate time-varying forces on the wall.
- Identified the coexistence of stagnant and flowing zones upstream of the wall.
Conclusions:
- The developed model provides a reasonable estimation of granular avalanche forces on walls.
- Further research is needed to refine the understanding of the upstream stagnant zone dynamics.
- Findings are valuable for the design of avalanche defense structures.
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