The mechanical origin of snow avalanche dynamics and flow regime transitions
Snow avalanches cause fatalities and economic damage. Key to their mitigation is the understanding of snow avalanche dynamics. This study investigates the dynamic behavior of snow avalanches, using the material point method (MPM) and an elastoplastic constitutive law for porous cohesive materials. B...
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ftethz:oai:www.research-collection.ethz.ch:20.500.11850/621090 2023-07-30T04:07:14+02:00 The mechanical origin of snow avalanche dynamics and flow regime transitions Li, Xingyue Sovilla, Betty Jiang, Chenfanfu Gaume, Johan id_orcid:0 000-0001-8931-752X 2020-10 application/application/pdf https://hdl.handle.net/20.500.11850/621090 https://doi.org/10.3929/ethz-b-000619962 en eng Copernicus info:eu-repo/semantics/altIdentifier/doi/10.5194/tc-14-3381-2020 http://hdl.handle.net/20.500.11850/621090 doi:10.3929/ethz-b-000619962 info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International The Cryosphere, 14 (10) info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2020 ftethz https://doi.org/20.500.11850/62109010.3929/ethz-b-00061996210.5194/tc-14-3381-2020 2023-07-16T23:49:05Z Snow avalanches cause fatalities and economic damage. Key to their mitigation is the understanding of snow avalanche dynamics. This study investigates the dynamic behavior of snow avalanches, using the material point method (MPM) and an elastoplastic constitutive law for porous cohesive materials. By virtue of the hybrid EulerianLagrangian nature of the MPM, we can handle processes involving large deformations, collisions and fractures. Meanwhile, the elastoplastic model enables us to capture the mixed-mode failure of snow, including tensile, shear and compressive failure. Using the proposed numerical approach, distinct behaviors of snow avalanches, from fluid-like to solid-like, are examined with varied snow mechanical properties. In particular, four flow regimes reported from real observations are identified, namely, cold dense, warm shear, warm plug and sliding slab regimes. Moreover, notable surges and roll waves are observed peculiarly for flows in transition from cold dense to warm shear regimes. Each of the flow regimes shows unique flow characteristics in terms of the evolution of the avalanche front, the free-surface shape, and the vertical velocity profile. We further explore the influence of slope geometry on the behavior of snow avalanches, including the effect of slope angle and path length on the maximum flow velocity, the runout angle and the deposit height. Unified trends are obtained between the normalized maximum flow velocity and the scaled runout angle as well as the scaled deposit height, reflecting analogous rules with different geometry conditions of the slope. It is found that the maximum flow velocity is mainly controlled by the friction between the bed and the flow, the geometry of the slope, and the snow properties. We reveal the crucial effect of both flow and deposition behaviors on the runout angle. Furthermore, our MPM modeling is calibrated and tested with simulations of real snow avalanches. The evolution of the avalanche front position and velocity from the MPM modeling shows ... Article in Journal/Newspaper The Cryosphere ETH Zürich Research Collection |
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Open Polar |
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ETH Zürich Research Collection |
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language |
English |
description |
Snow avalanches cause fatalities and economic damage. Key to their mitigation is the understanding of snow avalanche dynamics. This study investigates the dynamic behavior of snow avalanches, using the material point method (MPM) and an elastoplastic constitutive law for porous cohesive materials. By virtue of the hybrid EulerianLagrangian nature of the MPM, we can handle processes involving large deformations, collisions and fractures. Meanwhile, the elastoplastic model enables us to capture the mixed-mode failure of snow, including tensile, shear and compressive failure. Using the proposed numerical approach, distinct behaviors of snow avalanches, from fluid-like to solid-like, are examined with varied snow mechanical properties. In particular, four flow regimes reported from real observations are identified, namely, cold dense, warm shear, warm plug and sliding slab regimes. Moreover, notable surges and roll waves are observed peculiarly for flows in transition from cold dense to warm shear regimes. Each of the flow regimes shows unique flow characteristics in terms of the evolution of the avalanche front, the free-surface shape, and the vertical velocity profile. We further explore the influence of slope geometry on the behavior of snow avalanches, including the effect of slope angle and path length on the maximum flow velocity, the runout angle and the deposit height. Unified trends are obtained between the normalized maximum flow velocity and the scaled runout angle as well as the scaled deposit height, reflecting analogous rules with different geometry conditions of the slope. It is found that the maximum flow velocity is mainly controlled by the friction between the bed and the flow, the geometry of the slope, and the snow properties. We reveal the crucial effect of both flow and deposition behaviors on the runout angle. Furthermore, our MPM modeling is calibrated and tested with simulations of real snow avalanches. The evolution of the avalanche front position and velocity from the MPM modeling shows ... |
format |
Article in Journal/Newspaper |
author |
Li, Xingyue Sovilla, Betty Jiang, Chenfanfu Gaume, Johan id_orcid:0 000-0001-8931-752X |
spellingShingle |
Li, Xingyue Sovilla, Betty Jiang, Chenfanfu Gaume, Johan id_orcid:0 000-0001-8931-752X The mechanical origin of snow avalanche dynamics and flow regime transitions |
author_facet |
Li, Xingyue Sovilla, Betty Jiang, Chenfanfu Gaume, Johan id_orcid:0 000-0001-8931-752X |
author_sort |
Li, Xingyue |
title |
The mechanical origin of snow avalanche dynamics and flow regime transitions |
title_short |
The mechanical origin of snow avalanche dynamics and flow regime transitions |
title_full |
The mechanical origin of snow avalanche dynamics and flow regime transitions |
title_fullStr |
The mechanical origin of snow avalanche dynamics and flow regime transitions |
title_full_unstemmed |
The mechanical origin of snow avalanche dynamics and flow regime transitions |
title_sort |
mechanical origin of snow avalanche dynamics and flow regime transitions |
publisher |
Copernicus |
publishDate |
2020 |
url |
https://hdl.handle.net/20.500.11850/621090 https://doi.org/10.3929/ethz-b-000619962 |
genre |
The Cryosphere |
genre_facet |
The Cryosphere |
op_source |
The Cryosphere, 14 (10) |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/tc-14-3381-2020 http://hdl.handle.net/20.500.11850/621090 doi:10.3929/ethz-b-000619962 |
op_rights |
info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International |
op_doi |
https://doi.org/20.500.11850/62109010.3929/ethz-b-00061996210.5194/tc-14-3381-2020 |
_version_ |
1772820446269407232 |