Wind Design Procedures for Wood Roof Trusses of Low-Rise Structures
Publication: Journal of Architectural Engineering
Volume 26, Issue 3
Abstract
Wind design procedures for wood roof trusses of low-rise structures are evaluated in this paper using wind tunnel test data and two-dimensional finite-element frame models. The adequacy of the conventional and two alternative design procedures is determined by computing the combined stress index in the top chord and the reliability index, β conditioned on the occurrence of the design wind speed. For trusses with typical design dead loads and constructed with wood that exhibits a relatively low degree of variability in material design values, the results indicate that both the conventional and the alternative design procedures considered in this study meet a target reliability index equal to 3.0. Of the three procedures, replacing main wind force resisting system (MWFRS) loads on a chord segment with components and cladding (C&C) loads, while maintaining MWFRS loads on all other chord member segments, provides the closest match to the target β. For trusses constructed with wood that exhibits a relatively high degree of variability in material design values, the reliability index is lower for all design procedures.
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Acknowledgments
Funding for this research was provided in part by the Insurance Institute for Business and Home Safety (IBHS) and by the University of Wyoming. The views expressed in this paper are those of the authors and do not necessarily reflect the views of those acknowledged.
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Published In
Journal of Architectural Engineering
Volume 26 • Issue 3 • September 2020
Copyright
© 2020 American Society of Civil Engineers.
History
Received: Jul 19, 2019
Accepted: Apr 2, 2020
Published online: Jun 16, 2020
Published in print: Sep 1, 2020
Discussion open until: Nov 16, 2020
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