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.
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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.
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Information & Authors
Information
Published In
Journal of Cold Regions Engineering
Volume 28 • Issue 2 • June 2014
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
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