Shear strengthening of reinforced concrete T-beams under cyclic loading with TRM or FRP jackets
- 787 Downloads
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.
- 1.ACI 549.4R-13 (2013). Guide to design and construction of externally bonded fabric-reinforced cementitious matrix (FRCM) systems for repair and strengthening concrete and masonry structures, American Concrete Institute, Farmington Hills, USAGoogle Scholar
- 3.ASTM D638 (2010) Standard test method for tensile properties of plastics. American Society for Testing and MaterialsGoogle Scholar
- 7.EN 1015-11 (1993) Methods of test for mortar for masonry—Part 11: Determination of flexural and compressive strength of hardened mortar. European Committee for Standardization, BrusselsGoogle Scholar
- 8.Eshwar N, Nanni A, Ibell TJ (2008) Performance of two anchor systems of externally bonded fiber-reinforced polymer laminates. ACI Mater J 105(1):72–80Google Scholar
- 10.Kalfat R, Al-Mahaidi R, Smith ST (2013) Anchorage devices used to improve the performance of reinforced concrete beams retrofitted with FRP composites: a state-of-the-art review. ASCE J Compos Constr 17(1):14–33Google Scholar
- 12.Kim Y, Quinn KT, Satrom CN, Ghannoum WM, Jirsa JO (2011) Shear strengthening RC T-beams using CFRP laminates and anchors, vol. 36. In: 10th International symposium on fiber-reinforced polymer reinforcement for concrete structures, American Concrete Institute, SP-275, pp 1–17Google Scholar
- 14.Sato Y, Ueda T, Kakuta Y, Ono S (1997a) Ultimate shear capacity of reinforced concrete beams with carbon fiber sheet, vol. 1. In: Non-metallic (FRP) reinforcement for concrete structures, Japan Concrete Institute, pp 499–506Google Scholar
- 15.Sato Y, Katsumata H, Kobatake Y (1997b) Shear strengthening of existing reinforced concrete beams by CFRP sheet, vol. 1. In: Non-metallic (FRP) reinforcement for concrete structures, Japan Concrete Institute, pp 507–514Google Scholar
- 16.Triantafillou TC (1998) Shear strengthening of reinforced concrete beams using epoxy-bonded FRP composites. ACI Struct J 95(2):107–115Google Scholar
- 17.Triantafillou TC, Papanicolaou CG (2006) Shear strengthening of RC members with textile reinforced mortar (TRM) jackets. Mater Struct 39(1):85–93Google Scholar
- 18.Triantafillou TC, Papanicolaou CG, Zisimopoulos P, Laourdekis T (2006) Concrete confinement with textile reinforced mortar (TRM) jackets. ACI Struct J 103(1):28–37Google Scholar