Practical Solution to Wood Truss Assembly Design Problems
Publication: Practice Periodical on Structural Design and Construction
Volume 9, Issue 1
Abstract
This study analyzed an actual metal-plate-connected wood truss assembly using a system design procedure (SDP) to investigate some of the behavioral issues that may be present in an actual, complex roof-truss assembly. The assembly is in use in the United States, and the designs of all of its trusses were obtained from a truss-plate manufacturer (TPM). The TPM had designed the assembly by designing individual trusses using a conventional design procedure (CDP). The combined stress indices (CSI) of individual trusses from the CDP were compared with the CSI obtained from the SDP. Using SDP, the CSI for one member of a truss increased over 1.0 (indicating failure) in the assembly, demonstrating that redesigning the member by using SDP may increase safety. The CSI values for most other trusses decreased (by as much as 43%), indicating potential truss fabrication cost reductions using SDP. The predictions of maximum CSI and its location using SDP differed from those based on CDP. The study has demonstrated that various “system” related issues (e.g., interaction of subassemblies, boundary conditions, etc.) strongly influence the behavior of an assembly, which may not be considered in CDP.
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Information & Authors
Information
Published In
Practice Periodical on Structural Design and Construction
Volume 9 • Issue 1 • February 2004
Pages: 54 - 60
Copyright
Copyright © 2004 American Society of Civil Engineers.
History
Received: Sep 6, 2002
Accepted: Sep 6, 2002
Published online: Jan 16, 2004
Published in print: Feb 2004
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