Influence of Base Plate Flexibility on the Fatigue Performance of Welded Socket Connections
Publication: Journal of Structural Engineering
Volume 134, Issue 6
Abstract
This study investigates the effect of base plate flexibility on the behavior and fatigue performance of welded socket connections commonly used in sign support structures. The results of a three specimen static load testing program, extensive finite-element analysis, and parametric study are discussed. Results clearly show that base plate flexibility, primarily base plate thickness, has a major influence on the stress distribution in the tube wall adjacent to the welded socket connection. Currently, AASHTO gives no specific guidance on the design of the base plates for sign support structures that explicitly address flexibility. Increasing base plate thickness is shown to be a very effective method to improve the fatigue resistance of this detail. Based on this trend, a simple procedure that incorporates the influence of base plate flexibility into the infinite life, nominal stress approach to fatigue design is proposed.
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Acknowledgments
The research was sponsored by the City of Philadelphia and the Pennsylvania Infrastructure Technology Alliance (PITA) Program. The writers appreciate the efforts of Mr. John Hoffner and the ATLSS laboratory technical staff for their support in the laboratory. In addition, Mr. Carl Bowman and Mr. Ian Hodgson greatly assisted with the field efforts and data reduction. The writers are also grateful to Mr. Carl Macchietto and Valmont Industries for their support with respect to the laboratory specimens.
References
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Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 134 • Issue 6 • June 2008
Pages: 911 - 918
Copyright
© 2008 ASCE.
History
Received: Mar 24, 2006
Accepted: Nov 28, 2007
Published online: Jun 1, 2008
Published in print: Jun 2008
Notes
Note. Associate Editor: James S. Davidson
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