Shear strengthening of reinforced concrete T-beams under cyclic loading with TRM or FRP jackets
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The paper presents a systematic investigation on the effectiveness of U-shaped textile-reinforced mortar (TRM) jackets as shear strengthening materials of reinforced concrete T-beams, by examining a number of parameters not studied before: cyclic loading; fixed support conditions; different types of textiles; different numbers of layers; anchors; the relative performance of TRM versus equivalent FRP systems; and different displacement amplitudes of the loading cycles. For beams without anchors it is concluded that the effectiveness of TRM increases non-proportionally with the number of layers and that, for the same total volume fraction of fibers in the jacket, one layer of textile is more effective than two. For beams with anchored TRM jackets it is concluded that the effectiveness of the strengthening system is quite high, as is the effectiveness of an anchored FRP system. The results are used to derive simple analytical models for the effective strain in anchored or non-anchored TRM jackets.
KeywordsAnchors Cyclic loading Fiber-reinforced polymers (FRP) Reinforced concrete Shear strengthening T-beams Textile-reinforced mortar (TRM)
The authors wish to thank the students S. Maroudas, I. Marabeas, A. Michael, D. Sardeli, P. Katsapis and L. Koutas, for their assistance in the experimental program. Special thanks go to the technician K. Karlos. The research described in this paper has been co-financed by the European Union (European Social Fund—ESF) and Greek national funds through the Operational Program “Education and Lifelong Learning” of the National Strategic Reference Framework (NSRF)—Research Funding Program THALES—Investing in knowledge through the European Social Fund.
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