Abstract
In this study, two types of shear-deficient beams having different stirrup spacing (150 mm c/c and 300 mm c/c) were used. The performances of shear-deficient beam strengthened with externally and internally wrapped GFRP were tested under three-point bending monotonic loading. The load-carrying capacity of GFRP-wrapped beam was found to be significantly increased in comparison to the unstrengthened (control) beam and was the highest in both externally and internally bonded shear-deficient beams, i.e., 39.60% and 45.3%, respectively. Significant increment was also observed in flexural ductility, energy absorption and inelastic performance of the strengthened beams. The performance of the externally GFRP-wrapped RC beam (GFRP–epoxy-bonded RC beam) was better than that of the internally wrapped beam. However, because of the low economy index, internal wrapping is more suitable as a strengthening technique than external wrapping.
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Abbreviations
- A st :
-
Cross-sectional area of the internal shear reinforcement
- A wg :
-
Cross-sectional area of the external shear reinforcement
- f y , st :
-
Yield strength of steel reinforcement
- f c :
-
28 Days compressive strength of concrete
- S s :
-
Spacing between internal shear reinforcement
- S g :
-
Spacing between external shear reinforcement
- Mu/Fu :
-
Shear span of RC beam
- E g :
-
Modulus elasticity of GFRP material
- ε g , eff :
-
Effective strain of GFRP
- d g :
-
Depth of bonded material
- d s :
-
Depth of shear reinforcement
- θ :
-
Angle of diagonal shear crack (45°)
- α s :
-
Angle of reinforced steel (900)
- α g :
-
Angle of bonded material (900)
- P y :
-
Yield load
- P m :
-
Maximum load of beam specimen
- P f :
-
Ultimate load at failure stage
- ∆ y :
-
Yield displacement
- ∆ m :
-
Displacement at maximum load stage
- ∆ f :
-
Ultimate displacement at failure stage
- μ :
-
Ductility factor
- F :
-
Flexural strength as given in ASTM-2010 C293/C293M
- L :
-
Span length
- b :
-
Average width of specimen at the fracture
- d :
-
Average depth of specimen at the fracture
- k :
-
Stiffness of beam
- p :
-
Load
- δ:
-
Deformation
- F deg :
-
Post-elastic strength degradation over yield strength
- K deg :
-
Post-elastic stiffness degradation over yield stiffness
- k y :
-
Yield stiffness
- F y :
-
Yield strength
References
Khalifa A, Nanni A (2002) Rehabilitation of rectangular simply supported RC beams with shear deficiencies using CFRP composites. Constr Build Mater 16:135–146. https://doi.org/10.1016/S0950-0618(02)00002-8
Björn T (2003) Strengthening concrete beams for shear with CFRP sheets. Constr Build Mater 17:15–26. https://doi.org/10.1016/S0950-0618(02)00088-0
Bukhari IA, Vollum RL, Ahmad S, Sagaseta J (2010) Shear strengthening of reinforced concrete beams with CFRP. Mag Concr Res 62(1):65–77. https://doi.org/10.1680/macr.2008.62.1.65
Li X, Bian R, Wu G (2019) Flexural behaviour of RC beams strengthened with combinations of two CFRP systems and P-SWRs. Mag Concr Res 71(14):749–760. https://doi.org/10.1680/jmacr.17.00487
Anil Ö (2006) Improving shear capacity of RC T-beams using CFRP composites subjected to cyclic load. Cem Concr Compos 28:638–649. https://doi.org/10.1016/j.cemconcomp.2006.04.004
Wang J, Hota GR, Liang R, Zhou D, Liu W, Fang Y (2015) Durability of glass fiber-reinforced polymer composites under the combined effects of moisture and sustained loads. J Reinf Plast Compos 34(21):1739–1754
Robert M, Cousin P, Benmokrane B (2009) Durability of GFRP reinforcing bars embedded in moist concrete. J Compos Constr 13:66–73
Kamal ASM, Boulfiza M (2011) Durability of GFRP rebars in simulated concrete solutions under accelerated aging conditions. J Compos Constr 15:473–481
Sundarraja MC, Rajamohan S (2009) Strengthening of RC beams in shear using GFRP inclined strips—an experimental study. Constr Build Mater 23:856–864. https://doi.org/10.1016/j.conbuildmat.2008.04.008
Banjara NK, Ramanjaneyulu K (2017) Experimental and numerical investigations on the performance evaluation of shear deficient and GFRP strengthened reinforced concrete beams. Constr Build Mater 137:520–534. https://doi.org/10.1016/j.conbuildmat.2017.01.089
EI-Mogy M, EI-Ragaby A, EI-Salakawy E (2013) Experimental testing and finite element modeling on continuous concrete beams reinforced with fibre reinforced polymer bars and stirrups. Can J Civ Eng 40(11):1091–1102. https://doi.org/10.1139/cjce-2012-0509
IS 456 (2000) Code of practice for plain and reinforced concrete, Bureau of Indian Standards
IS 516 (1959) Method of tests for strength of concrete, Bureau of Indian Standards
IS 5816 (1999) Method of test splitting tensile strength of concrete, Bureau of Indian Standards
Nanda RP, Khan HA, Pal A (2017) Seismic-retrofitting-of-unreinforced-brick-masonry-panels-with-glass-fibre-reinforced-polymers. Int J Geo Earth Eng 8(1):28–37
ACI 440.2R-08 (2008) Guide for the design and construction of externally bonded FRP systems for strengthening concrete structures
American Society for Testing and Materials (ASTM) (2010) Standard test method for flexural strength of concrete (using simple beam with center-point loading, C293/C293M-10
Khan HA, Nanda RP (2020) Out-of-plane bending of masonry wallette strengthened with geosynthetic. Constr Build Mater. https://doi.org/10.1016/j.conbuildmat.2019.117198
Tawfik AS, Badr MR, ELZanaty A (2014) Behavior and ductility of high strength reinforced concrete frames. HBRC J Pub 10(2):215–221. https://doi.org/10.1016/j.hbrcj.2013.11.005
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Nanda, R.P., Behera, B. Experimental Study of Shear-Deficient RC Beam Wrapped with GFRP. Int J Civ Eng 18, 655–664 (2020). https://doi.org/10.1007/s40999-020-00498-4
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DOI: https://doi.org/10.1007/s40999-020-00498-4