Use of FEA for Design of Posttensioning Anchor Head
Publication: Journal of Bridge Engineering
Volume 12, Issue 2
Abstract
This paper deals with the development process of a multistrand wedge anchor head mechanism. Generally, this development process involves a number of different experimental tests but, while informative and necessary, these tests cannot provide valuable information such as internal strain distributions, stress concentrations, or percentage of the anchorage yielded volume. To answer these questions, an efficient numerical finite element model has been developed and validated which includes nonlinearities such as: large strain; plasticity; and contact between interfaces. First, this paper presents a comparison between numerical and experimental results of VSL International CS 6-31 anchorage mechanism under standard loading conditions. Based on the good agreement between results, the numerical model was then used to assess the anchorage behavior under more severe loading conditions and improved mechanical characteristics. Through anchorage deflection, von Mises stresses as well as equivalent plastic strains, it is shown that the anchor areas most severely stressed are concentrated along its peripheral wedge cavities and that, while suitable for typical loadings, the VSL anchorage is not acceptable for the more severe loading conditions examined. Finally, this paper underlines the proposed numerical model usefulness with regard to the development of new post-tensioned anchorages by providing information not otherwise available.
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Acknowledgments
The writers would like to gratefully acknowledge the collaboration of Mr. Bruno Lecailtel and Mr. Adrian Gnagi from VSL International Ltd. Partial financial support by the Quebec Ministry of Transportation, the Natural Sciences and Engineering Research Council of Canada, and the Quebec Ministry of Education (Fonds FCAR), is also gratefully acknowledged.
References
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Information & Authors
Information
Published In
Journal of Bridge Engineering
Volume 12 • Issue 2 • March 2007
Pages: 194 - 204
Copyright
© 2007 ASCE.
History
Received: Jun 27, 2002
Accepted: Mar 16, 2005
Published online: Mar 1, 2007
Published in print: Mar 2007
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