Structures Congress 2019
Predicted Slip of Ballasted Solar Arrays on Angled Roofs Due to Seismic Motion
Publication: Structures Congress 2019: Blast, Impact Loading, and Research and Education
ABSTRACT
During the design and installation of rooftop solar systems, it is often desirable for architectural reasons to support the solar panels without anchors attached to the structure, depending on friction for lateral resistance. This scenario has previously been studied with shake table tests and analysis in OpenSees and SAP 2000, resulting in the publication of a SEAOC standard. This paper contributes closed-form equations and fast-running code that will allow the development of simple design equations and probabilistic approaches. The proposed governing equations are presented then validated by comparison to an equivalent analysis with SAP 2000. Once validated, the equations are used to produce parametric plots of slip as a function of friction coefficient, roof slope, and intensity of roof shaking. This study is a proof of concept using a single earthquake record scaled to various intensity levels; other limitations and planned future work are detailed.
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Acknowledgements and Statement of Work
This material is based upon work supported by the National Science Foundation under Grant No. 1531582. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation. Support from the Gunjit S. Sikand Faculty Research Fellowship and the Nabih Youssef Graduate Fellowship are gratefully acknowledged.
The first author developed the theoretical model, developed the final versions of the Matlab code and the SAP model, and wrote the manuscript. The second and third authors developed early versions of the SAP and Matlab code and contributed to the direction of the project. All authors, including, the fourth author read and discussed the literature.
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Published In
Structures Congress 2019: Blast, Impact Loading, and Research and Education
Pages: 326 - 339
Editor: James Gregory Soules, McDermott International
ISBN (Online): 978-0-7844-8224-7
Copyright
© 2019 American Society of Civil Engineers.
History
Published online: Apr 22, 2019
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