气候变化领域集成服务门户(CCPortal): Micromechanical modeling of snow failure

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DOI	10.5194/tc-14-39-2020
	Micromechanical modeling of snow failure
	Bobillier G.; Bergfeld B.; Capelli A.; Dual J.; Gaume J.; Van Herwijnen A.; Schweizer J.
发表日期	2020
ISSN	19940416
起始页码	39
结束页码	49
卷号	14 期号:1
英文摘要	Dry-snow slab avalanches start with the formation of a local failure in a highly porous weak layer underlying a cohesive snow slab. If followed by rapid crack propagation within the weak layer and finally a tensile fracture through the slab, a slab avalanche releases. While the basic concepts of avalanche release are relatively well understood, performing fracture experiments in the laboratory or in the field can be difficult due to the fragile nature of weak snow layers. Numerical simulations are a valuable tool for the study of micromechanical processes that lead to failure in snow.We used a three-dimensional discrete element method (3-D DEM) to simulate and analyze failure processes in snow. Cohesive and cohesionless ballistic deposition allowed us to reproduce porous weak layers and dense cohesive snow slabs, respectively. To analyze the micromechanical behavior at the scale of the snowpack (∼ 1 m), the particle size was chosen as a compromise between low computational costs and detailed representation of important micromechanical processes. The 3-D-DEM snow model allowed reproduction of the macroscopic behavior observed during compression and mixedmode loading of dry-snow slab and the weak snow layer. To be able to reproduce the range of snow behavior (elastic modulus, strength), relations between DEM particle and contact parameters and macroscopic behavior were established. Numerical load-controlled failure experiments were performed on small samples and compared to results from load-controlled laboratory tests. Overall, our results show that the discrete element method allows us to realistically simulate snow failure processes. Furthermore, the presented snow model seems appropriate for comprehensively studying how the mechanical properties of the slab and weak layer influence crack propagation preceding avalanche release. © Author(s) 2020.
英文关键词	compression; crack propagation; discrete element method; failure analysis; numerical model; porous medium; snow avalanche; snowpack; tensile stress
语种	英语
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202030
作者单位	WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland; Institute for Mechanical Systems, ETH Zurich, Zurich, Switzerland; SLAB Snow and Avalanche Simulation Laboratory, EPFL Swiss Federal Institute of Technology, Lausanne, Switzerland
推荐引用方式 GB/T 7714	Bobillier G.,Bergfeld B.,Capelli A.,et al. Micromechanical modeling of snow failure[J],2020,14(1).
APA	Bobillier G..,Bergfeld B..,Capelli A..,Dual J..,Gaume J..,...&Schweizer J..(2020).Micromechanical modeling of snow failure.Cryosphere,14(1).
MLA	Bobillier G.,et al."Micromechanical modeling of snow failure".Cryosphere 14.1(2020).