Snow Pressure on a Semiflexible Retaining Structure
Publication: Journal of Cold Regions Engineering
Volume 28, Issue 2
Abstract
Snow avalanche hazard is one of the most critical aspects in the urbanization of mountainous areas. The risk from these natural phenomena can be reduced if proper countermeasures for reducing the danger or preventing avalanche triggering are taken. For instance, in the avalanche initiation zone, devices able to withstand snowpack gliding and prevent crack propagation can be installed. These can be classified as rigid (snow bridges) or flexible (snow net) structures, depending on the mechanisms involved under snow loading. In recent years, a new kind of structure called a snow umbrella, based on a net panel supported by rigid beams, has been designed and installed in the northwestern Italian Alps. As the real behavior of these structures is far from being simple to understand because of the complex interaction with snowpack movements, an umbrella was instrumented and monitored during the winter season of 2010–2011. The recorded data are used for testing two possible pressure distributions and evaluating the magnitude of the forces acting on the structure. Furthermore, a back-analysis allows validation of the assumptions taken during the design of the devices. The results are compared with commonly used guidelines, and further suggestions are proposed.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The financial support provided by Regione Autonoma Valle d’Aosta, Assessorato opere pubbliche, difesa del suolo e edilizia residenziale pubblica, Direzione Assetto idrogeologico dei bacini montani in the framework of the Interreg Project RISK-NAT Italia/Francia (Alpi 2007-2013) is gratefully acknowledged. The authors would like to thank Dr E. Bovet, Prof B. Chiaia, Dr B. Frigo and Dr M. Maggioni for their contributions in the researches conduced onsite. Thanks also to Betonform for supplying the anchor plates later instrumented and installed in situ.
References
De Biagi, V., Chiaia, B., and Frigo, B. (2012a). “Structural back-analysis of avalanche impact on buildings.” Internal Rep., Politecnico di Torino, Italy.
De Biagi, V., Chiaia, B., and Frigo, B. (2012b). “Vulnerability of buildings against avalanche hazard.” Snow Engineering VII: Proc., 7th Int. Conf. on Snow Engineering, T. Fukuhara and T. Takahashi, eds., Fukui Univ., Fukui, Japan, 53–68.
Edwards, A. (1976). An introduction to linear regression and correlation, W. H. Freeman, San Francisco.
Haefeli, R. (1954). “Vorschläge zur konstruktion und berechnung von netzwerken.” Externer Bericht Nr. 2112, Eidgenössisches Institut für Schnee- und Lawinenforschung, Davos, Switzerland (in German).
Margreth, S. (2007). Defense structures in avalanche starting zones. Technical guideline as an aid to enforcement, Federal Office of the Environment Institut für Schnee- und Lawinenforschung (SLF), Bern/Davos, Switzerland.
McClung, D., and Schaerer, P. (2006). The avalanche handbook, Mountaineers Books, Seattle, WA.
Nicot, F. (2004). “From constitutive modelling of a snow cover to the design of flexible protective structures. Part I—Mechanical modelling.” Int. J. Solids Struct., 41(11–12), 3317–3337.
Nicot, F., Gay, M., and Tacnet, J. (2002). “Interaction between a snow mantel and a flexible structure: A new method to design avalanche nets.” Cold Reg. Sci. Tech., 34(2), 67–84.
Olivero, G. (2011). “Opere di difesa attiva dalle valanghe di neve: Studio teorico e sperimentale di una struttura a ombrello.” M.S. thesis, Politecnico di Torino, Torino, Italy (in Italian).
Peila, D., Oggeri, C., and Betti, V. (2005). “Studio sperimentale del comportamento di un nuovo modello di opera stabilizzatrice del manto nevoso.” GEAM, Geoingegneria ambientale e mineraria, XLII(1), 93–99 (in Italian).
Rainer, E., Rammer, L., and Wiatr, T. (2008). “Snow loads on defensive snow net systems.” Int. Symp. on Mitigative Measures against Snow Avalanches, T. Jóhannesson, G. Eiríksson, E. Hestnes, and J. Gunnarsson, eds., The Association of Chartered Engineers, Iceland, Reykjavik, 40–47.
Segor, V., Vicari, C., Saravalle, F., and Di Bella, R. (2010). “A new system of rapidly installed avalanche barriers.” Proc., Int. Snow Science Workshop 2010, Arc'teryx, North Vancouver, Canada.
Sellke, T., Bayarri, M. J., and Berger, J. O. (2001). “Calibration of values for testing precise null hypotheses.” Am. Stat., 55(1), 62–71.
U.S. National Research Council. (1990). Snow avalanche hazards and mitigation in the United States, National Academies Press Panel on Snow Avalanches and National Research Council, Committee on Ground Failure Hazards Mitigation Research, Washington, DC.
Information & Authors
Information
Published In
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Apr 29, 2013
Accepted: Jan 7, 2014
Published online: Feb 14, 2014
Published in print: Jun 1, 2014
Discussion open until: Jul 14, 2014
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.