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.
References
Aravinthan, T., Sabonchy, E., and Heldt, T. (2004). “Application of external posttensioning for strengthening of headstocks (bent-caps) in bridges.” Proc., 4th Int. Conf. on Concrete under Severe Conditions: Environment and Loading, Seoul National Univ. and Korea Concrete Institute, Seoul, South Korea, 1737–1744.
Aravinthan, T., Witchukreangkrai, E., and Mutsuyoshi, H. (2005). “Flexural behavior of two-span continuous prestressed concrete girders with highly eccentric external tendons.” ACI Struct. J., 102(3), 402–411.
Collins, M. P., and Mitchell, D. (1991). Prestressed concrete structures, Prentice-Hall, Englewood Cliffs, N.J.
Harajli, M. H. (1993). “Strengthening of concrete beams by external prestressing.” PCI J., 38(6), 76–88.
Khaloo, A. R. (2000). “Shear repair of reinforced concrete beams using posttensioning.” Proc. 4th Int. Conf. on Repair, Rehabilitation, and Maintenance of Concrete Structures, and Innovations in Design and Construction, ACI, Seoul, Korea, 519–550.
Kong, F. K., and Evans, R. H. (1993). Reinforced and prestressed concrete, ELBS, London.
Mutsuyoshi, H., Aravinthan, T., and Hikimura, T. (1998) “Retrofitting of RC and PC beams with external tendons and steel plate.” Proc., 2nd Int. Conf. on Concrete under Severe Conditions—Environment and Loading (CONSEC’98), Tromso, Norway, 1176–1184.
Pantelides, C. P., Gergely, J., and Reaveley, L. D. (2001). “In-situ verification of rehabilitation and repair of reinforced concrete bridge bents under simulated seismic loads.” Earthquake Spectra, 17(3), 507–530.
Pisani, M. A. (1999). “Strengthening by means of external prestressing.” J. Bridge Eng., 4(2), 131–135.
Tan, K. H., and Ng, C. K. (1998). “Effect of shear in externally prestressed beams.” ACI Struct. J., 95(2), 116–128.
Tan, K. H., and Tjandra, R. A. (2002). “Strengthening of continuous beams using various external tendon profiles.” Proc., 1st Fib Congress, Osaka, Japan.
Teng, S., Kong, F.-K., Poh, S. P., Guan, L. W., and Tan, K.-H. (1996). “Performance of strengthened concrete deep beams predamaged in shear.” ACI Struct. J., 93(2), 159–171.
Woods, E. A. (2004). “Shear strengthening and model testing of concrete bridge headstocks.” Undergraduate thesis, Univ. of Southern Queensland, Toowoomba, Australia.
Information & Authors
Information
Published In
Journal of Structural Engineering
Volume 133 • Issue 11 • November 2007
Pages: 1662 - 1669
Copyright
© 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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