气候变化领域集成服务门户(CCPortal): Snow fracture in relation to slab avalanche release: Critical state for the onset of crack propagation

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DOI	10.5194/tc-11-217-2017
	Snow fracture in relation to slab avalanche release: Critical state for the onset of crack propagation
	Gaume J.; Van Herwijnen A.; Chambon G.; Wever N.; Schweizer J.
发表日期	2017
ISSN	19940416
卷号	11 期号:1
英文摘要	The failure of a weak snow layer buried below cohesive slab layers is a necessary, but insufficient, condition for the release of a dry-snow slab avalanche. The size of the crack in the weak layer must also exceed a critical length to propagate across a slope. In contrast to pioneering shear-based approaches, recent developments account for weak layer collapse and allow for better explaining typical observations of remote triggering from low-angle terrain. However, these new models predict a critical length for crack propagation that is almost independent of slope angle, a rather surprising and counterintuitive result. Based on discrete element simulations we propose a new analytical expression for the critical crack length. This new model reconciles past approaches by considering for the first time the complex interplay between slab elasticity and the mechanical behavior of the weak layer including its structural collapse. The crack begins to propagate when the stress induced by slab loading and deformation at the crack tip exceeds the limit given by the failure envelope of the weak layer. The model can reproduce crack propagation on low-angle terrain and the decrease in critical length with increasing slope angle as modeled in numerical experiments. The good agreement of our new model with extensive field data and the ease of implementation in the snow cover model SNOWPACK opens a promising prospect for improving avalanche forecasting. © Author(s) 2017.
学科领域	avalanche; collapse; crack propagation; deformation mechanism; elasticity; numerical model; slope angle; slope dynamics; slope failure; snow cover
语种	英语
scopus关键词	avalanche; collapse; crack propagation; deformation mechanism; elasticity; numerical model; slope angle; slope dynamics; slope failure; snow cover
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/119454
作者单位	WSL Institute for Snow and Avalanche Research SLF, Davos, Switzerland; EPFL Swiss Federal Institute of Technology, School of Architecture, Civil and Environmental Engineering, Lausanne, Switzerland; Université Grenoble Alpes, Irstea, UR ETGR, Grenoble, France
推荐引用方式 GB/T 7714	Gaume J.,Van Herwijnen A.,Chambon G.,et al. Snow fracture in relation to slab avalanche release: Critical state for the onset of crack propagation[J],2017,11(1).
APA	Gaume J.,Van Herwijnen A.,Chambon G.,Wever N.,&Schweizer J..(2017).Snow fracture in relation to slab avalanche release: Critical state for the onset of crack propagation.Cryosphere,11(1).
MLA	Gaume J.,et al."Snow fracture in relation to slab avalanche release: Critical state for the onset of crack propagation".Cryosphere 11.1(2017).