Rain-on-Snow Surcharge for Roof Design
Publication: Journal of Structural Engineering
Volume 127, Issue 1
Abstract
A study of structural loading on gable roofs due to rain falling on an existing roof snowpack is presented. Rain-on-snow provisions in various existing standards are reviewed, and a summary of structural damage in the United States arguably related to rain-on-snow is presented. Three separate approaches are then used to quantify the intensity, duration, and return period for a rain-on-snow event. The first approach is case history information from a 1996/1997 rain-on-snow event (unknown return period). The second is a statistical approach in which the ground snow load plus daily rain with a 50-year return period is determined (unknown intensity and duration of the rain). The third is a two-year return period rain (unknown snow condition). Based upon the resulting roof surcharge loads, revised provisions for the ASCE 7 load standard are suggested. One possible revision is to only require a rain-on-snow surcharge for certain roofs with low slopes and short eave-to-ridge distances. An alternate revision is to simply eliminate the surcharge.
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References
1.
AIJ recommendations for loads on buildings. (1996). Architectural Institute of Japan, Tokyo.
2.
ASCE 7-98, minimum design loads for buildings and other structures. (1998). ASCE, Reston, Va.
3.
Colbeck, S. C. ( 1977). “Roof loads resulting from rain-on-snow.” Report 77-12, Cold Regions Research and Engineering Laboratory, Hanover, N.H.
4.
Del Corso, R. et al. ( 1996). “The new European code on snowloads.” Proc., 3rd Int. Conf. on Snow Engrg., Sendai Japan, Balkema, Rotterdam, The Netherlands.
5.
Ellingwood, B., and Redfield, R. (1983). “Ground snow loads for structural design.”J. Struct. Engrg., ASCE, 109(4), 950–964.
6.
Gray, D., and Male, D. eds. ( 1981). Handbook of snow: Principles, processes, management and use, Pergamon Press Canada/Willowdale, Ontario.
7.
National Building Code of Canada. (1995). National Research Council of Canada, Ottawa, Ont.
8.
Niedringhaus, T. E. ( 1972). “Distribution of mean monthly precipitation and rainfall intensities.” Spec. Rep. ETL-SR-72-5, U.S. Army Engineer Topographic Laboratories, Fort Belvoir, Va.
9.
Niedringhaus, T. E. ( 1973). “Rainfall intensities in the conterminous United States and Hawaii. Spec. Rep. ETL-SR-74-3, U.S. Army Engineer Topographic Laboratories, Fort Belvoir, Va.
10.
O'Rourke, M. J., and Downey, C. ( 1999). “Roof loads due to rain-on-snow surcharge.” Res. Rep., Dept. of Civ. Engrg., Rensselaer Polytechnic Institute, Troy, N.Y., 122.
11.
Structural Engineers Association of Washington (SEAW). ( 1998). “An analysis of building structural failures due to the holiday snow storms.” FEMA Mitigation Directorate, Bothell, Wash.
12.
Tabler, R. D. ( 1994). “Design guidelines for the control of blowing and drifting snow.” Strategic Hwy. Res. Prog. SHRP-H-381, National Research Council, Washington, D.C.
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Received: Mar 16, 2000
Published online: Jan 1, 2001
Published in print: Jan 2001
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