Results 1 to 10 of about 2,160 (115)

Fracture toughness of mixed-mode anticracks in highly porous materials [PDF]

Nature Communications
When porous materials are subjected to compressive loads, localized failure chains, commonly termed anticracks, can occur and cause large-scale structural failure.
Valentin Adam, Bastian Bergfeld, Philipp Weißgraeber, Alec van Herwijnen, Philipp L. Rosendahl   +4 more
doaj   +3 more sources

Role of Ice Mechanics on Snow Viscoplasticity

Geophysical Research Letters
The porous structure of snow becomes denser with time under gravity, primarily due to the creep of its ice matrix with viscoplasticity. Despite investigation of this behavior at the macroscopic scale, the driving microscopic mechanisms are still not well
Louis Védrine, Pascal Hagenmuller, Lionel Gélébart, Maurine Montagnat, Antoine Bernard   +4 more
doaj   +2 more sources

Crack propagation speeds in weak snowpack layers

Journal of Glaciology, 2022
For the release of a slab avalanche, crack propagation within a weak snowpack layer below a cohesive snow slab is required. As crack speed measurements can give insight into underlying processes, we analysed three crack propagation events that occurred ...
Bastian Bergfeld, Alec van Herwijnen, Grégoire Bobillier, Eric Larose, Ludovic Moreau, Bertil Trottet, Johan Gaume, Janic Cathomen, Jürg Dual, Jürg Schweizer   +9 more
doaj   +1 more source

Temporal evolution of crack propagation characteristics in a weak snowpack layer: conditions of crack arrest and sustained propagation [PDF]

Natural Hazards and Earth System Sciences, 2023
For a slab avalanche to release, we need sustained crack propagation in a weak snow layer beneath a cohesive snow slab – a process we call dynamic crack propagation. Field measurements on crack propagation are very scarce. We therefore performed a series
B. Bergfeld, A. van Herwijnen, G. Bobillier, P. L. Rosendahl, P. Weißgraeber, V. Adam, V. Adam, J. Dual, J. Schweizer   +8 more
doaj   +1 more source

Modeling spatially distributed snow instability at a regional scale using Alpine3D

Journal of Glaciology, 2021
Assessing the avalanche danger level requires snow stratigraphy and instability data. As such data are usually sparse, we investigated whether distributed snow cover modeling can be used to provide information on spatial instability patterns relevant for
Bettina Richter, Jürg Schweizer, Mathias W. Rotach, Alec van Herwijnen   +3 more
doaj   +1 more source

Automated prediction of wet-snow avalanche activity in the Swiss Alps

Journal of Glaciology, 2023
Wet-snow avalanches are triggered by the infiltration of liquid water which weakens the snowpack. Wet-snow avalanches are among the most destructive avalanches, yet their release mechanism is not sufficiently understood for a process-based prediction ...
Martin Hendrick, Frank Techel, Michele Volpi, Tasko Olevski, Cristina Pérez-Guillén, Alec van Herwijnen, Jürg Schweizer   +6 more
doaj   +1 more source

Disentangling creep and isothermal metamorphism during snow settlement with X-ray tomography

Journal of Glaciology, 2023
Once fallen, snow settles due to the combined effects of metamorphism and deformation of the ice matrix under gravity. To understand how these coupled processes affect snow evolution, we performed oedometric compression tests and continuously monitored ...
Antoine Bernard, Pascal Hagenmuller, Maurine Montagnat, Guillaume Chambon   +3 more
doaj   +1 more source

Assessing the Mechanisms Thought to Govern Ice and Snow Friction and Their Interplay With Substrate Brittle Behavior

Frontiers in Mechanical Engineering, 2021
Sliding friction on ice and snow is characteristically low at temperatures common on Earth’s surface. This slipperiness underlies efficient sleds, winter sports, and the need for specialized tires. Friction can also play a micro-mechanical role affecting
James H. Lever, Emily Asenath-Smith, Susan Taylor, Austin P. Lines   +3 more
doaj   +1 more source

Probabilistic size effect law for mode II fracture from critical lengths in snow slab avalanche weak layers

Journal of Glaciology, 2019
From field observations, dry snow slab avalanche initiation is associated with fracture within relatively thin weak layers under stronger, cohesive slabs.
D. M. McCLUNG, C. P. BORSTAD
doaj   +1 more source

Angle of repose experiments with snow: role of grain shape and cohesion

Journal of Glaciology, 2020
Snow appears as a granular material in most engineering applications. We examined the role of grain shape and cohesion in angle of repose experiments, which are a common means for the characterization of granular materials. The role of shape was examined
Carolin Willibald, Henning Löwe, Thiemo Theile, Jürg Dual, Martin Schneebeli   +4 more
doaj   +1 more source