Research article 17 Jan 2020
Research article | 17 Jan 2020
Modeling snow slab avalanches caused by weak-layer failure – Part 2: Coupled mixed-mode criterion for skier-triggered anticracks
Philipp L. Rosendahl and Philipp Weißgraeber
Related authors
Philipp L. Rosendahl and Philipp Weißgraeber
The Cryosphere, 14, 115–130, https://doi.org/10.5194/tc-14-115-2020, https://doi.org/10.5194/tc-14-115-2020, 2020
Short summary
Short summary
Dry-snow slab avalanche release is preceded by a fracture process within the snowpack. Recognizing weak layer collapse as an integral part of the fracture process is crucial and explains phenomena such as whumpf sounds and remote triggering of avalanches from low-angle terrain. In this first part of the two-part work we propose a novel closed-form analytical model for a snowpack that provides a highly efficient and precise analysis of the mechanical response of a loaded snowpack.
Philipp L. Rosendahl and Philipp Weißgraeber
The Cryosphere, 14, 115–130, https://doi.org/10.5194/tc-14-115-2020, https://doi.org/10.5194/tc-14-115-2020, 2020
Short summary
Short summary
Dry-snow slab avalanche release is preceded by a fracture process within the snowpack. Recognizing weak layer collapse as an integral part of the fracture process is crucial and explains phenomena such as whumpf sounds and remote triggering of avalanches from low-angle terrain. In this first part of the two-part work we propose a novel closed-form analytical model for a snowpack that provides a highly efficient and precise analysis of the mechanical response of a loaded snowpack.
Related subject area
Discipline: Snow | Subject: Snow Physics
Macroscopic water vapor diffusion is not enhanced in snow
Modelling perennial firn aquifers in the Antarctic Peninsula (1979–2016)
Snow albedo sensitivity to macroscopic surface roughness using a new ray-tracing model
A model for French-press experiments of dry snow compaction
Identification of blowing snow particles in images from a Multi-Angle Snowflake Camera
Modeling snow slab avalanches caused by weak-layer failure – Part 1: Slabs on compliant and collapsible weak layers
Modeling the evolution of the structural anisotropy of snow
Motion of dust particles in dry snow under temperature gradient metamorphism
Influence of light-absorbing particles on snow spectral irradiance profiles
Saharan dust events in the European Alps: role in snowmelt and geochemical characterization
On the suitability of the Thorpe–Mason model for calculating sublimation of saltating snow
The influence of layering and barometric pumping on firn air transport in a 2-D model
Kévin Fourteau, Florent Domine, and Pascal Hagenmuller
The Cryosphere, 15, 389–406, https://doi.org/10.5194/tc-15-389-2021, https://doi.org/10.5194/tc-15-389-2021, 2021
Short summary
Short summary
There has been a long controversy to determine whether the effective diffusion coefficient of water vapor in snow is superior to that in free air. Using theory and numerical modeling, we show that while water vapor diffuses more than inert gases thanks to its interaction with the ice, the effective diffusion coefficient of water vapor in snow remains inferior to that in free air. This suggests that other transport mechanisms are responsible for the large vapor fluxes observed in some snowpacks.
J. Melchior van Wessem, Christian R. Steger, Nander Wever, and Michiel R. van den Broeke
The Cryosphere Discuss., https://doi.org/10.5194/tc-2020-148, https://doi.org/10.5194/tc-2020-148, 2020
Revised manuscript accepted for TC
Short summary
Short summary
This study presents the first modelled estimates of perennial firn aquifers (PFAs) in Antarctica. PFAs are subsurface meltwater bodies that do not refreeze in winter due to the isolating effects of the snow they are buried underneath. They have first been identified in Greenland, but conditions for their existence are also present in the Antarctic Peninsula. These PFAs can have important effects on meltwater retention and ice shelf stability and, consequently, sea-level rise.
Fanny Larue, Ghislain Picard, Laurent Arnaud, Inès Ollivier, Clément Delcourt, Maxim Lamare, François Tuzet, Jesus Revuelto, and Marie Dumont
The Cryosphere, 14, 1651–1672, https://doi.org/10.5194/tc-14-1651-2020, https://doi.org/10.5194/tc-14-1651-2020, 2020
Short summary
Short summary
The effect of surface roughness on snow albedo is often overlooked,
although a small change in albedo may strongly affect the surface energy
budget. By carving artificial roughness in an initially smooth snowpack,
we highlight albedo reductions of 0.03–0.04 at 700 nm and 0.06–0.10 at 1000 nm. A model using photon transport is developed to compute albedo considering roughness and applied to understand the impact of roughness as a function of snow properties and illumination conditions.
Colin R. Meyer, Kaitlin M. Keegan, Ian Baker, and Robert L. Hawley
The Cryosphere, 14, 1449–1458, https://doi.org/10.5194/tc-14-1449-2020, https://doi.org/10.5194/tc-14-1449-2020, 2020
Short summary
Short summary
We describe snow compaction laboratory data with a new mathematical model. Using a compression device that is similar to a French press with snow instead of coffee grounds, Wang and Baker (2013) compacted numerous snow samples of different densities at a constant velocity to determine the force required for snow compaction. Our mathematical model for compaction includes airflow through snow and predicts the required force, in agreement with the experimental data.
Mathieu Schaer, Christophe Praz, and Alexis Berne
The Cryosphere, 14, 367–384, https://doi.org/10.5194/tc-14-367-2020, https://doi.org/10.5194/tc-14-367-2020, 2020
Short summary
Short summary
Wind and precipitation often occur together, making the distinction between particles coming from the atmosphere and those blown by the wind difficult. This is however a crucial task to accurately close the surface mass balance. We propose an algorithm based on Gaussian mixture models to separate blowing snow and precipitation in images collected by a Multi-Angle Snowflake Camera (MASC). The algorithm is trained and (positively) evaluated using data collected in the Swiss Alps and in Antarctica.
Philipp L. Rosendahl and Philipp Weißgraeber
The Cryosphere, 14, 115–130, https://doi.org/10.5194/tc-14-115-2020, https://doi.org/10.5194/tc-14-115-2020, 2020
Short summary
Short summary
Dry-snow slab avalanche release is preceded by a fracture process within the snowpack. Recognizing weak layer collapse as an integral part of the fracture process is crucial and explains phenomena such as whumpf sounds and remote triggering of avalanches from low-angle terrain. In this first part of the two-part work we propose a novel closed-form analytical model for a snowpack that provides a highly efficient and precise analysis of the mechanical response of a loaded snowpack.
Silvan Leinss, Henning Löwe, Martin Proksch, and Anna Kontu
The Cryosphere, 14, 51–75, https://doi.org/10.5194/tc-14-51-2020, https://doi.org/10.5194/tc-14-51-2020, 2020
Short summary
Short summary
The anisotropy of the snow microstructure, given by horizontally aligned ice crystals and vertically interlinked crystal chains, is a key quantity to understand mechanical, dielectric, and thermodynamical properties of snow. We present a model which describes the temporal evolution of the anisotropy. The model is driven by snow temperature, temperature gradient, and the strain rate. The model is calibrated by polarimetric radar data (CPD) and validated by computer tomographic 3-D snow images.
Pascal Hagenmuller, Frederic Flin, Marie Dumont, François Tuzet, Isabel Peinke, Philippe Lapalus, Anne Dufour, Jacques Roulle, Laurent Pézard, Didier Voisin, Edward Ando, Sabine Rolland du Roscoat, and Pascal Charrier
The Cryosphere, 13, 2345–2359, https://doi.org/10.5194/tc-13-2345-2019, https://doi.org/10.5194/tc-13-2345-2019, 2019
Short summary
Short summary
Light–absorbing particles (LAPs, e.g. dust or black carbon) in snow are a potent climate forcing agent. Their presence darkens the snow surface and leads to higher solar energy absorption. Several studies have quantified this radiative impact by assuming that LAPs were motionless in dry snow, without any clear evidence of this assumption. Using time–lapse X–ray tomography, we show that temperature gradient metamorphism of snow induces downward motion of LAPs, leading to self–cleaning of snow.
Francois Tuzet, Marie Dumont, Laurent Arnaud, Didier Voisin, Maxim Lamare, Fanny Larue, Jesus Revuelto, and Ghislain Picard
The Cryosphere, 13, 2169–2187, https://doi.org/10.5194/tc-13-2169-2019, https://doi.org/10.5194/tc-13-2169-2019, 2019
Short summary
Short summary
Here we present a novel method to estimate the impurity content (e.g. black carbon or mineral dust) in Alpine snow based on measurements of light extinction profiles. This method is proposed as an alternative to chemical measurements, allowing rapid retrievals of vertical concentrations of impurities in the snowpack. In addition, the results provide a better understanding of the impact of impurities on visible light extinction in snow.
Biagio Di Mauro, Roberto Garzonio, Micol Rossini, Gianluca Filippa, Paolo Pogliotti, Marta Galvagno, Umberto Morra di Cella, Mirco Migliavacca, Giovanni Baccolo, Massimiliano Clemenza, Barbara Delmonte, Valter Maggi, Marie Dumont, François Tuzet, Matthieu Lafaysse, Samuel Morin, Edoardo Cremonese, and Roberto Colombo
The Cryosphere, 13, 1147–1165, https://doi.org/10.5194/tc-13-1147-2019, https://doi.org/10.5194/tc-13-1147-2019, 2019
Short summary
Short summary
The snow albedo reduction due to dust from arid regions alters the melting dynamics of the snowpack, resulting in earlier snowmelt. We estimate up to 38 days of anticipated snow disappearance for a season that was characterized by a strong dust deposition event. This process has a series of further impacts. For example, earlier snowmelts may alter the hydrological cycle in the Alps, induce higher sensitivity to late summer drought, and finally impact vegetation and animal phenology.
Varun Sharma, Francesco Comola, and Michael Lehning
The Cryosphere, 12, 3499–3509, https://doi.org/10.5194/tc-12-3499-2018, https://doi.org/10.5194/tc-12-3499-2018, 2018
Short summary
Short summary
The Thorpe-Mason (TM) model describes how an ice grain sublimates during aeolian transport. We revisit this classic model using simple numerical experiments and discover that for many common scenarios, the model is likely to underestimate the amount of ice loss. Extending this result to drifting and blowing snow using high-resolution turbulent flow simulations, the study shows that current estimates for ice loss due to sublimation in regions such as Antarctica need to be significantly updated.
Benjamin Birner, Christo Buizert, Till J. W. Wagner, and Jeffrey P. Severinghaus
The Cryosphere, 12, 2021–2037, https://doi.org/10.5194/tc-12-2021-2018, https://doi.org/10.5194/tc-12-2021-2018, 2018
Short summary
Short summary
Ancient air enclosed in bubbles of the Antarctic ice sheet is a key source of information about the Earth's past climate. However, a range of physical processes in the snow layer atop an ice sheet may change the trapped air's chemical composition before it is occluded in the ice. We developed the first detailed 2-D computer simulation of these processes and found a new method to improve the reconstruction of past climate from air in ice cores bubbles.
Cited articles
Anderson, T. L.: Fracture Mechanics, CRC Press, Boca Raton, 4th edn.,
https://doi.org/10.1201/9781315370293, 2017. a
ASTM Standard D3433-99: Standard Test Method for Fracture Strength in
Cleavage of Adhesives in Bonded Metal Joints, ASTM International, West
Conshohocken, PA, https://doi.org/10.1520/D3433-99R12, 2012. a
ASTM Standard E399-17: Standard Test Method for Linear-Elastic Plane-Strain
Fracture Toughness KIc of Metallic Materials, ASTM International, West
Conshohocken, PA, https://doi.org/10.1520/E0399-17, 2017. a
Bader, H. and Salm, B.: On the mechanics of snow slab release, Cold Reg. Sci. Technol., 17, 287–300, 1990. a
Bair, E., Gaume, J., and van Herwijnen, A.: The role of collapse in avalanche
release: review and implications for practitioners and future research, in:
Proceedings of the International Snow Science Workshop, Breckenridge, CO,
USA, 2 October 2016, 24–31, 2016. a
Bair, E. H., Simenhois, R., van Herwijnen, A., and Birkeland, K.: The influence of edge effects on crack propagation in snow stability tests, The Cryosphere, 8, 1407–1418, https://doi.org/10.5194/tc-8-1407-2014, 2014. a
Bažant, Z. P.: Size Effect in Blunt Fracture: Concrete, Rock, Metal,
J. Eng. Mech., 110, 518–535,
https://doi.org/10.1061/(ASCE)0733-9399(1984)110:4(518), 1984. a
Bažant, Z. P., Zi, G., and McClung, D. M.: Size effect law and fracture mechanics of the triggering of dry snow slab avalanches, J.
Geophys. Res.-Sol. Ea., 108, 2119, https://doi.org/10.1029/2002JB001884,
2003. a, b
Benzeggagh, M. L. and Kenane, M.: Measurement of mixed-mode delamination
fracture toughness of unidirectional glass/epoxy composites with mixed-mode
bending apparatus, Compos. Sci. Technol., 56, 439–449,
https://doi.org/10.1016/0266-3538(96)00005-X, 1996. a
Birkeland, K. W., van Herwijnen, A., Reuter, B., and Bergfeld, B.: Temporal
changes in the mechanical properties of snow related to crack propagation
after loading, Cold Reg. Sci. Technol., 159, 142–152,
https://doi.org/10.1016/j.coldregions.2018.11.007, 2019a. a
Birkeland, K. W., van Herwijnen, A., Reuter, B., and Bergfeld, B.: Temporal
changes in the mechanical properties of snow related to crack propagation
after loading, Cold Reg. Sci. Technol., 159, 142–152,
2019b. a
Bobillier, G., Gaume, J., van Herwijnen, A., Dual, J., and Schweizer, J.:
Modeling the propagation saw test with discrete elements, in: Proceedings
of the International Snow Science Workshop ISSW 2018, edited by: Fischer,
J.-T., Adams, M., Dobesberger, P., Fromm, R., Gobiet, A., Granig, M.,
Mitterer, C., Nairz, P., Tollinger, C., and Walcher, M.,
Innsbruck, Austria, 976–980, 2018. a
Broberg, K. B.: Cracks and fracture, Elsevier, 1999. a
Chiaia, B. M., Cornetti, P., and Frigo, B.: Triggering of dry snow slab
avalanches: stress versus fracture mechanical approach, Cold Reg. Sci. Technol., 53, 170–178, https://doi.org/10.1016/j.coldregions.2007.08.003, 2008. a
Christen, M., Kowalski, J., and Bartelt, P.: RAMMS: Numerical simulation of
dense snow avalanches in three-dimensional terrain, Cold Reg. Sci. Technol., 63, 1–14, 2010. a
Dundurs, J. and Markenscoff, X.: A Green’s function formulation of anticracks
and their interaction with load-induced singularities, J. Appl. Mech., 56, 550–555, 1989. a
Felger, J., Rosendahl, P. L., Leguillon, D., and Becker, W.: Predicting crack patterns at bi-material junctions: A coupled stress and energy approach, Int. J. Solids Struct., 164, 191–201,
https://doi.org/10.1016/j.ijsolstr.2019.01.015, 2019. a
Fletcher, R. C. and Pollard, D. D.: Anticrack model for pressure solution
surfaces, Geology, 9, 419–424, 1981. a
Föhn, P. M. B.: The stability index and various triggering mechanisms, in: Avalanche Formation, Movement and Effects, Proceedings of the Davos Symposium, Davos, September 1986, IAHS Publ., 195–214, 1987. a
Fonselius, M.: Effect of size on the bending strength of laminated veneer
lumber, Wood Sci. Technol., 31, 399–413, https://doi.org/10.1007/BF00702562,
1997. a, b
Gaume, J., van Herwijnen, A., Chambon, G., Birkeland, K. W., and Schweizer, J.: Modeling of crack propagation in weak snowpack layers using the discrete element method, The Cryosphere, 9, 1915–1932, https://doi.org/10.5194/tc-9-1915-2015, 2015. a, b
Gaume, J., Gast, T., Teran, J., van Herwijnen, A., and Jiang, C.: Dynamic
anticrack propagation in snow, Nat. Commun., 9, 3047, https://doi.org/10.1038/s41467-018-05181-w, 2018. a
Gauthier, D. and Jamieson, B.: Evaluation of a prototype field test for
fracture and failure propagation propensity in weak snowpack layers, Cold Reg. Sci. Technol., 51, 87–97,
https://doi.org/10.1016/j.coldregions.2007.04.005, 2008a. a
Gauthier, D. and Jamieson, B.: Fracture propagation propensity in relation to
snow slab avalanche release: Validating the Propagation Saw Test, Geophys.
Res. Lett., 35, L13501, https://doi.org/10.1029/2008GL034245, 2008b. a, b
Hashin, Z.: Finite thermoelastic fracture criterion with application to
laminate cracking analysis, J. Mech. Phys. Solids,
44, 1129–1145, https://doi.org/10.1016/0022-5096(95)00080-1, 1996. a
Heierli, J.: Solitary fracture waves in metastable snow stratifications,
J. Geophys. Res.-Earth, 110, F02008, https://doi.org/10.1029/2004JF000178, 2005. a
Heierli, J.: Anticrack model for slab avalanche release, PhD thesis,
Universität Karlsruhe, 2008. a
Heierli, J. and Zaiser, M.: Failure initiation in snow stratifications
containing weak layers: Nucleation of whumpfs and slab avalanches, Cold Reg. Sci. Technol., 52, 385–400,
https://doi.org/10.1016/j.coldregions.2007.02.007, 2008. a, b
Heierli, J., Gumbsch, P., and Zaiser, M.: Anticrack nucleation as triggering
mechanism for snow slab avalanches, Science, 321, 240–243,
https://doi.org/10.1126/science.1153948, 2008. a
Hutchinson, J. W. and Suo, Z.: Mixed Mode Cracking in Layered Materials, J. Appl. Mech., 27, 63–191,
https://doi.org/10.1016/S0065-2156(08)70164-9, 1991. a
Jamieson, B. and Johnston, C. D.: Snowpack factors associated with strength
changes of buried surface hoar layers, Cold Reg. Sci. Technol.,
30, 19–34, https://doi.org/10.1016/S0165-232X(99)00026-9, 1999. a
Jamieson, B. and Schweizer, J.: Texture and strength changes of buried
surface-hoar layers with implications for dry snow-slab avalanche release,
J. Glaciol., 46, 151–160, https://doi.org/10.3189/172756500781833278, 2000. a
Köchle, B. and Schneebeli, M.: Three-dimensional microstructure and
numerical calculation of elastic properties of alpine snow with a focus on
weak layers, J. Glaciol., 60, 705–713,
https://doi.org/10.3189/2014JoG13J220, 2014. a
Leguillon, D.: Strength or toughness? A criterion for crack onset at a notch, Eur. J. Mech. A-Solid, 21, 61–72,
https://doi.org/10.1016/S0997-7538(01)01184-6, 2002. a, b, c
Leguillon, D., Martin, É., and Lafarie-Frenot, M.-C.: Flexural vs.
tensile strength in brittle materials, CR Mecanique, 343,
275–281, https://doi.org/10.1016/j.crme.2015.02.003, 2015. a, b
Louchet, F.: A transition in dry-snow slab avalanche triggering modes, Ann. Glaciol., 32, 285–289, 2001. a
Mahajan, P., Kalakuntla, R., and Chandel, C.: Numerical simulation of failure
in a layered thin snowpack under skier load, Ann. Glaciol., 51,
169–175, 2010. a
McClung, D. M.: Fracture mechanical models of dry slab avalanche release,
J. Geophys. Res.-Sol. Ea., 86, 10783–10790, 1981. a
McClung, D. M. and Schweizer, J.: Skier triggering, snow temperatures and the stability index for dry-slab avalanche initiation, J. Glaciol., 45, 190–200, https://doi.org/10.3189/002214399793377121, 1999. a
Monti, F., Gaume, J., van Herwijnen, A., and Schweizer, J.: Snow instability evaluation: calculating the skier-induced stress in a multi-layered snowpack, Nat. Hazards Earth Syst. Sci., 16, 775–788, https://doi.org/10.5194/nhess-16-775-2016, 2016. a
Narita, H.: An experimental study on tensile fracture of snow, Contributions
from the institute of Low Temperature Science, 32, 1–37, 1984. a
Podolskiy, E., Chambon, G., Naaim, M., and Gaume, J.: A review of
finite-element modelling in snow mechanics, J. Glaciol., 59,
1189–1201, 2013. a
Reiweger, I. and Schweizer, J.: Failure of a layer of buried surface hoar,
Geophys. Res. Lett., 37, L24501, https://doi.org/10.1029/2010GL045433, 2010. a
Reuter, B. and Schweizer, J.: Describing Snow Instability by Failure
Initiation, Crack Propagation, and Slab Tensile Support, Geophys.
Res. Lett., 45, 7019–7027, https://doi.org/10.1029/2018GL078069, 2018. a
Reuter, B., Schweizer, J., and van Herwijnen, A.: A process-based approach to estimate point snow instability, The Cryosphere, 9, 837–847, https://doi.org/10.5194/tc-9-837-2015, 2015. a, b
Reuter, B., Calonne, N., and Adams, E.: Shear failure of weak snow layers in the first hours after burial, The Cryosphere Discuss., https://doi.org/10.5194/tc-2018-268, 2019. a
Rosendahl, P. L., Weißgraeber, P., Stein, N., and Becker, W.: Asymmetric
crack onset at open-holes under tensile and in-plane bending loading,
Int. J. Solids Struct., 113-114, 10–23,
https://doi.org/10.1016/j.ijsolstr.2016.09.011, 2017. a
Rosendahl, P., Staudt, Y., Schneider, A., Schneider, J., and Becker, W.:
Nonlinear elastic finite fracture mechanics: modeling mixed-mode crack
nucleation in structural glazing silicone sealants, Mater. Design,
108057, https://doi.org/10.1016/j.matdes.2019.108057, 2019a. a
Rosendahl, P. L., Drass, M., Felger, J., Schneider, J., and Becker, W.:
Equivalent strain failure criterion for multiaxially loaded incompressible
hyperelastic elastomers, Int. J. Solids Struct.,
166, 32–46, https://doi.org/10.1016/j.ijsolstr.2019.01.030, 2019b. a
Rosendahl, P. L., Staudt, Y., Odenbreit, C., Schneider, J., and Becker, W.:
Measuring mode I fracture properties of thick-layered structural silicone
sealants, Int. J. Adhes. Adhes., 91, 64–71,
https://doi.org/10.1016/j.ijadhadh.2019.02.012, 2019c. a
Sapora, A. and Cornetti, P.: Crack onset and propagation stability from a
circular hole under biaxial loading, Int. J. Fracture, 214,
97–104, 2018. a
Savage, S. B. and Hutter, K.: The motion of a finite mass of granular material down a rough incline, J. Fluid Mech., 199, 177–215, 1989. a
Scapozza, C.: Entwicklung eines dichte- und temperaturabhängigen
Stoffgesetzes zur Beschreibung des visko-elastischen Verhaltens von Schnee,
PhD thesis, ETH Zürich, https://doi.org/10.3929/ethz-a-004680249, 2004.
a
Schweizer, J.: Review of dry snow slab avalanche release, Cold Reg.
Sci. Technol., 30, 43–57, https://doi.org/10.1016/S0165-232X(99)00025-7,
1999. a, b
Schweizer, J. and Camponovo, C.: The skier's zone of influence in triggering
slab avalanches, Ann. Glaciol., 32, 314–320,
https://doi.org/10.3189/172756401781819300, 2001. a
Schweizer, J., Jamieson, B., and Schneebeli, M.: Snow avalanche formation,
Rev. Geophys., 41, 1016, https://doi.org/10.1029/2002RG000123, 2003. a, b
Sigrist, C. and Schweizer, J.: Critical energy release rates of weak snowpack layers determined in field experiments, Geophys. Res. Lett., 34, L03502, https://doi.org/10.1029/2006GL028576, 2007. a
Stein, N., Weißgraeber, P., and Becker, W.: A model for brittle failure in adhesive lap joints of arbitrary joint configuration, Compos. Struct., 133, 707–718, https://doi.org/10.1016/j.compstruct.2015.07.100, 2015. a
van Herwijnen, A. and Jamieson, B.: High-speed photography of fractures in
weak snowpack layers, Cold Reg.
Sci. Technol., 43, 71–82, https://doi.org/10.1016/j.coldregions.2005.05.005, 2005. a
van Herwijnen, A. and Jamieson, B.: Snowpack properties associated with
fracture initiation and propagation resulting in skier-triggered dry snow
slab avalanches, Cold Reg.
Sci. Technol., 50, 13–22,
https://doi.org/10.1016/j.coldregions.2007.02.004, 2007. a
van Herwijnen, A. and Miller, D. A.: Experimental and numerical investigation of the sintering rate of snow, J. Glaciol., 59, 269–274, https://doi.org/10.3189/2013JoG12J094, 2013. a
van Herwijnen, A., Gaume, J., Bair, E. H., Reuter, B., Birkeland, K. W., and
Schweizer, J.: Estimating the effective elastic modulus and specific
fracture energy of snowpack layers from field experiments, J.
Glaciol., 62, 997–1007, https://doi.org/10.1017/jog.2016.90, 2016. a
Waddoups, M. E., Eisenmann, J. R., and Kaminski, B. E.: Macroscopic fracture
mechanics of advanced composite materials, J. Compos. Mater., 5,
446–454, 1971. a
Weißgraeber, P., Felger, J., Geipel, D., and Becker, W.: Cracks at
elliptical holes: Stress intensity factor and Finite Fracture Mechanics
solution, Eur. J. Mech. A-Solid, 55, 192–198,
https://doi.org/10.1016/j.euromechsol.2015.09.002, 2015. a
Weißgraeber, P., Hell, S., and Becker, W.: Crack nucleation in negative
geometries, Eng. Fract. Mech., 168, 93–104,
https://doi.org/10.1016/j.engfracmech.2016.02.045, 2016a. a, b
Weißgraeber, P., Leguillon, D., and Becker, W.: A review of Finite
Fracture Mechanics: crack initiation at singular and non-singular stress
raisers, Arch. Appl. Mech., 86, 375–401,
https://doi.org/10.1007/s00419-015-1091-7, 2016b. a, b
Short summary
Dry-snow slab avalanche release is preceded by a fracture process within the snowpack. Recognizing weak layer collapse as an integral part of the fracture process is crucial and explains phenomena such as whumpf sounds and remote triggering of avalanches from low-angle terrain. In this second part of the two-part work we propose a novel mixed-mode coupled stress and energy failure criterion for nucleation of weak layer failure due to external loading of the snowpack.
Dry-snow slab avalanche release is preceded by a fracture process within the snowpack....