Stability Analysis of Metal-Plate-Connected Wood Truss Assemblies
Publication: Journal of Structural Engineering
Volume 138, Issue 9
Abstract
This paper presents a study on the critical buckling load and lateral bracing force of metal-plate-connected (MPC) wood truss assemblies. A three-dimensional finite-element method (FEM) based computer program was developed, calibrated, and verified with test results. A preliminary reliability analysis was conducted based on the verified FEM model, with consideration of the variation in material properties and the initial out-of-plane deflection of compression webs. The out-of-plane rotational stiffness of MPC connections has a significant effect on the critical buckling load and lateral bracing force ratio of MPC trusses. The critical buckling load could almost be doubled on the basis of an ideally pinned compression web, and the lateral bracing force ratio was found to be generally less than 1% from the test results and numerical analysis. Consequently, the currently used 2% rule of thumb for lateral bracing design may be conservative, by overestimating the lateral bracing force, and may lead to oversized bracing members.
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Acknowledgments
This research work was done during the first author’s doctoral study at the Department of Wood Science of the University of British Columbia, Canada. It was sponsored by the Natural Sciences and Engineering Research Council of Canada (grant no. CRDP J 315282), the Canadian Wood Council, Western Wood Truss Association, Jager Building Systems, Alpine Systems Corp., and Miteck. Acknowledgment is also given to Dr. Ricardo O. Foschi for his enlightening direction and suggestions on this research work.
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Published In
Journal of Structural Engineering
Volume 138 • Issue 9 • September 2012
Pages: 1110 - 1119
Copyright
© 2012 American Society of Civil Engineers.
History
Received: May 22, 2010
Accepted: Sep 22, 2011
Published online: Sep 26, 2011
Published in print: Sep 1, 2012
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