Seismic Design of Ballasted Solar Arrays on Low-Slope Roofs
Publication: Journal of Structural Engineering
Volume 140, Issue 1
Abstract
Currently, ASCE standards require that nonstructural components of a building be positively attached to the building in regions of moderate to high seismicity. However, for solar arrays that bear on low-slope roofs, friction between the array and roof surface limits or prevents sliding of the array in an earthquake. In many cases, the seismic performance of such arrays can be shown by analysis to meet the design intent of the building code without being fastened to the building structure. This paper presents a methodology for estimating the sliding displacement corresponding to ASCE standards for design-level earthquake shaking. The writers conducted nonlinear response-history analyses considering a range of different seismicity levels, roof slopes, and coefficients of friction, which lead to design values of sliding seismic displacement for solar arrays in different conditions. Important aspects of a broadly applicable analysis include performing testing to determine appropriate coefficients of friction, performing analysis with earthquake records spectrally matched to broadband response spectra, and considering the effect of vertical earthquake motion on frictional response.
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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 and SunLink.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 140 • Issue 1 • January 2014
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Apr 6, 2012
Accepted: May 4, 2013
Published online: May 6, 2013
Published in print: Jan 1, 2014
Discussion open until: Feb 16, 2014
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