Analytical Simulation of Snow Drift Loading
Publication: Journal of Structural Engineering
Volume 131, Issue 4
Abstract
An analytical procedure for simulating roof snow drift loads is presented. The procedure is based upon the physics of drift formation and consists of two elements. The first element is the transport rate which quantifies the snow flux from the snow source area. The second element is the trapping efficiency which quantifies the percentage of transported snow from the source area which is captured at the drift. Knowing wind speed and snowfall information for a given winter, the procedure can be used to simulate the annual maximum drift for a given snow source area. The method is applied to over of weather data at each of over 50 NWS first-order sites across the United States. The calculated annual maxima are fit with an extreme value distribution to determine drift loads for both roof step and gable roof geometries. It is shown that current leeward roof step drift provisions in ASCE 7-02 as well as gable roof drift provisions proposed for ASCE 7-05 yield loads with something close to a mean recurrence interval.
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Acknowledgments
The results presented were an outgrowth of a research project sponsored by the American Iron and Steel Institute, the Metal Building Manufacturers Association, and the Structural Engineering Institute of ASCE. The writers gratefully acknowledge this support. However the findings and opinions are the writers alone and do not necessarily reflect the views of the sponsors.
References
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 131 • Issue 4 • April 2005
Pages: 660 - 667
Copyright
© 2005 ASCE.
History
Received: Dec 23, 2003
Accepted: May 17, 2004
Published online: Apr 1, 2005
Published in print: Apr 2005
Notes
Note. Associate Editor: Shahram Sarkani
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