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TECHNICAL PAPER

shear reinforcement and more severely test the anchors ability roving and epoxy adhesive. The first author also gratefully
to prevent complete debonding of the FRP U-wraps. The current acknowledges the financial assistance of the Ministry of Science
test results indicate that the 30° pre-crack constitutes the critical and Technology of China, the Tianjin Government and Nankai
case and future tests may be performed using cracks with this University towards the preparation of this paper.
inclination. The 30° is believed to be more critical because the
crack extends into sections along the beam with higher moment REFERENCES
to shear ratio than in beams with 45° pre-crack, and high
moment to shear ratio reduces the beam shear strength. [1] The Canadian Network of Centres of Excellence on
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strengthening beams in shear. The anchor can be made in- strengthening concrete girders in shear", Transportation
situ and is inspired by the so-called π-anchor tested by other Research Board, Washington DC, USA.
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retrofitted could only achieve 60% of the strength of the [6] Mofidi, A., Chaallal, O., Benmokrane, B., & Neale, K.
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ACKNOWLEDGEMENTS [8] Grelle, S. V., and Sneed, L. H. (2013). "Review of anchorage
systems for externally bonded FRP laminates", Journal of
The authors gratefully acknowledge the financial support of Concrete Structures and Materials, Vol. 17, No. 1, pp. 17-33.
the natural sciences and engineering research council (NSERC)
Canada and McMaster University towards this investigation. [9] Jinno, Y., Tsukagoshi, H., and Yabe, Y. (2001). "RC beams
Special thanks to the technical staff of the Applied Dynamics with slabs strengthened by CF sheets and bundles of CF",
Lab at McMaster University for their assistance during the 5 International Conference on Fiber-Reinforced Plastics
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preparation and execution of the tests. The authors are for Reinforced Concrete Structures, London, UK,
thankful to Sika Canada for donating the carbon fiber fabric, pp. 981-998.

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