Effects of Existing Shear Damage on Externally Posttensioned Repair of Bent Caps
Publication: Journal of Structural Engineering
Volume 133, Issue 11
Abstract
External posttensioning can be considered an effective strengthening method for bridge members, which are deteriorating due to extreme loading conditions and progressive structural aging. The effects of existing shear cracks in bent caps strengthened by external posttensioning were experimentally investigated using model specimens. Initial investigation revealed that the shear capacity of a bent cap is not enhanced by external posttensioning only, when shear cracks exist. Moreover, it was found that the repair of existing cracks using epoxy injection substantially increases the shear capacity of the bent cap. The Tenthill Creek Bridge in South East Queensland, Australia provides a case study where the bent caps have been strengthened by external posttensioning. The model tests of the bridge bent caps confirmed the initial findings on the effects of existing shear cracks on the shear capacity. The experimental results emphasize the need for appropriate repair of existing shear cracks prior to strengthening by external posttensioning to enhance the shear capacity of bent caps.
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Acknowledgments
This research project was funded by the University of Southern Queensland through the Research Project Program grant scheme, which is gratefully acknowledged. Sincere gratitude is expressed to Mr. Grant Snelling and Mr. Evan Woods, former undergraduate students of the University of Southern Queensland for their assistance in conducting parts of the experiments.
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© 2007 ASCE.
History
Received: Jan 23, 2006
Accepted: Nov 27, 2006
Published online: Nov 1, 2007
Published in print: Nov 2007
Notes
Note. Associate Editor: Yahya C. Kurama
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