Load-Duration Behavior of Wood Connections
Publication: Journal of Structural Engineering
Volume 131, Issue 9
Abstract
The time-effect factors , used in design to account for the load-duration effect were developed through long-term testing of wood members in flexure, yet they are applied to wood connections as well. This study examines time-effect factors for steel-doweled wood connections. In this study, long-term tests were performed on small-scale wood connection specimens, and the resulting time-to-failure data were used to calibrate two cumulative damage (CD) models. A numerical approach was developed for calibrating existing CD models to the test data. Step load tests also were performed on full-scale bolted connection specimens and the results were compared to the results predicted by the CD models fit to the long-term data. The calibrated CD models were then used in a relatively simple procedure to determine an approximate for steel-doweled wood connections ASCE-16 stipulates a of 0.80 for both snow load and occupancy live load. The best fitting models for the long-term test data produced 7 and ’s, representative of live and snow load, respectively, between 0.68 and 0.70 for the CD model used in the United States code development and 0.74–0.78 for a model used in Canada. The models which fit step-load test results the best produced a range of 0.86–0.88.
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Acknowledgments
The writers would like to thank Mr. Zeno Martin and Mr. David Claus for their assistance in gathering the test data used in this study. This paper is based on work supported by the Cooperative State Research, Education, and Extension Service, U.S. Department of Agriculture, under Grant No. UNSPECIFIED97-35103-4897. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the writers and do not necessarily reflect the view of the U.S. Department of Agriculture.
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 131 • Issue 9 • September 2005
Pages: 1434 - 1443
Copyright
© 2005 ASCE.
History
Received: Feb 2, 2003
Accepted: Nov 19, 2004
Published online: Sep 1, 2005
Published in print: Sep 2005
Notes
Note. Associate Editor: J. Daniel Dolan
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