Wind Design Practice and Recommendations for Solar Arrays on Low-Slope Roofs
Publication: Journal of Structural Engineering
Volume 140, Issue 2
Abstract
Currently, ASCE standards do not provide specific guidance on wind loads for solar arrays of photovoltaic panels, in terms of either prescriptive design or requirements for wind tunnel testing. Guidance is needed, particularly for arrays of low-profile tilted panels on flat or low-slope roofs, because they are markedly different aerodynamically from structures currently addressed in the building code. This paper presents recommendations for the structural design of these solar arrays for wind-loading. Recommendations include (1) categorizing solar array support-systems according to their height above the building roof and how they distribute forces to the roof, (2) developing pressure coefficients that are applicable to structurally interconnected roof-bearing support systems, (3) considering load cases that include uniform wind pressure on the array and nonuniform (gust) patterns, (4) determining appropriate stiffness and boundary conditions for structural analysis, and (5) use of testing to verify behavior and calibrate analytical models.
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Acknowledgments
The writers gratefully acknowledge the California Solar Initiative for partially funding the research described in this paper. The writers are grateful for the ongoing support of solar research and development by Mr. Chris Tilley and Dr. Mike Williams of SunLink. The research described in this paper was carried out at Rutherford + Chekene, SunLink, and the University of Western Ontario.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 140 • Issue 2 • February 2014
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Apr 6, 2012
Accepted: Jan 14, 2013
Published online: Jan 16, 2013
Published in print: Feb 1, 2014
Discussion open until: Feb 26, 2014
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