A Parametric Study on the Flexural Strengthening of Reinforced Concrete Beams with Near Surface Mounted FRP Bars
Abstract
FRP rods as lightweight materials with extraordinary properties of high strength to weight ratio, corrosion resistance, potentially high overall durability, tailor ability and high specific attributes are one of the most favorable materials to strengthen existing reinforced structures. The present study aimed to identify the behavior of reinforced concrete flexural beams strengthened with fiber reinforced polymer (FRP) rods through near surface mounted method (NSM). The results of the current study were based on nonlinear finite element software ABAQUS which can accurately simulate the experimental investigations on flexural behavior of reinforced concrete beams strengthened with NSM FRP rods. Validation of the proposed model was confirmed first by making a comparison with the experimental study presented in the literature. A parametric analysis was conducted on validated specimens to investigate the effect of FRP rod diameters, rod arrangements, FRP materials, as well as rods groove intervals on flexural behavior of strengthened reinforced beams. The numerical results of mid-span bending moment deflection, ultimate bending moment, failure deflection and ductility index were reported. For the sake of simplicity to be used by engineers, the results of the current study were drawn in the form of design charts and tables.
Keywords
References
Sharif, A., Al-Sulaimani, G., Basunbul, I., Baluch, M., and Ghaleb, B., “Strengthening of initially loaded reinforced concrete beams using FRP platesâ€, ACI Structural Journal, 91 (2), 160-168, 1994. https://doi.org/10.14359/4594.
Grace, N.F., Sayed, G., Soliman, A., and Saleh, K., “Strengthening reinforced concrete beams using fiber reinforced polymer (FRP) laminatesâ€, ACI Structural Journal-American Concrete Institute, 96(5), 865-874, 1999. https://doi.org/10.14359/741.
Nordin, H., and Täljsten, B., “Concrete beams strengthened with prestressed near surface mounted CFRPâ€, Journal of Composites for Construction, 10(1), 60-68, 2006. https://doi.org/10.1061/(asce)1090-0268(2006)10:1(60).
Bakis, C.E., Ganjehlou, A., Kachlakev, D.I., Schupack, M., Balaguru, P., Gee, D.J., Karbhari, V.M., Scott, D.W., Ballinger, C.A., and Gentry, T.R., “Guide for the design and construction of externally bonded FRP systems for strengthening concrete structuresâ€, Reported by ACI Committee, 440, 2002.
Hollaway, L.C., and Teng, J.-G., Strengthening and rehabilitation of civil infrastructures using fibre-reinforced polymer (FRP) composites, Elsevier, 2008.
Bilotta, A., Ceroni, F., Barros, J.A., Costa, I., Palmieri, A., Szabó, Z.K., Nigro, E., Matthys, S., Balazs, G.L., and Pecce, M., “Bond of NSM FRP-strengthened concrete: Round robin test initiativeâ€, Journal of Composites for Construction, 20, 2015. https://doi.org/10.1061/(asce)cc.1943-5614.0000579.
Bilotta, A., Ceroni, F., Nigro, E., and Pecce, M., “Efficiency of CFRP NSM strips and EBR plates for flexural strengthening of RC beams and loading pattern influenceâ€, Composite Structures, 124, 163-175, 2015. https://doi.org/10.1016/j.compstruct.2014.12.046
De Lorenzis, L., and Teng, J., “Near-surface mounted FRP reinforcement: An emerging technique for strengthening structuresâ€, Composites Part B: Engineering, 38, 119-143, 2007. https://doi.org/10.1016/j.compositesb.2006.08.003
Bilotta, A., Ceroni, F., Di Ludovico, M., Nigro, E., Pecce, M., and Manfredi, G., “Bond efficiency of EBR and NSM FRP systems for strengthening concrete membersâ€, Journal of Composites for Construction, 15, 757-772, 2011. https://doi.org/10.1061/(asce)cc.1943-5614.0000204.
Burke, P., “Low and High Temperature Performance of Near Surface Mounted FRP Strengthened Concrete Slabs,†Department of Civil Engineering, Queen’s University, 2008.
Sharaky, I.A., Torres, L., Comas, J., and Barris, C., “Flexural response of reinforced concrete (RC) beams strengthened with near surface mounted (NSM) fibre reinforced polymer (FRP) barsâ€, Composite Structures, 109, 8-22, 2014. https://doi.org/10.1016/j.compstruct.2013.10.051.
Nguyen, D.M., Chan, T.K., and Cheong, H.K., “Brittle failure and bond development length of CFRP-concrete beamsâ€, Journal of Composites for Construction, 5, 12-17, 2001. https://doi.org/10.1061/(asce)1090-0268(2001)5:1(12).
Novidis, D., Pantazopoulou, S., and Tentolouris, E., “Experimental study of bond of NSM-FRP reinforcementâ€, Construction and Building Materials, 21, 1760-1770, 2007. https://doi.org/10.1016/j.conbuildmat.2006.05.054.
Al-Mahmoud, F., Castel, A., François, R., and Tourneur, C., “Strengthening of RC members with near-surface mounted CFRP rodsâ€, Composite Structures, 91, 138-147, 2009. https://doi.org/10.1016/j.compstruct.2009.04.040.
Barros, J.A., and Fortes, A., “Flexural strengthening of concrete beams with CFRP laminates bonded into slitsâ€, Cement and Concrete Composites, 27, 471-480, 2005. https://doi.org/10.1016/j.cemconcomp.2004.07.004.
Lee, D., Cheng, L., and Yan-Gee Hui, J., “Bond characteristics of various NSM FRP reinforcements in concreteâ€, Journal of Composites for Construction, 17, 117-129, 2012. https://doi.org/10.1061/(asce)cc.1943-5614.0000318.
Lu, W., Ling, Z., Geng, Q., Liu, W., Yang, H., and Yue, K., “Study on flexural behaviour of glulam beams reinforced by Near Surface Mounted (NSM) CFRP laminatesâ€, Construction and Building Materials, 91, 23-31, 2015. https://doi.org/10.1016/j.conbuildmat.2015.04.050.
Rizzo, A., and De Lorenzis, L., “Behavior and capacity of RC beams strengthened in shear with NSM FRP reinforcementâ€, Construction and Building Materials, 23, 1555-1567, 2009. https://doi.org/10.1016/j.conbuildmat.2007.08.014.
Sharaky, I.A., Torres, L., Baena, M., and Vilanova, I., “Effect of different material and construction details on the bond behaviour of NSM FRP bars in concreteâ€, Construction and Building Materials, 38, 890-902, 2013. https://doi.org/10.1016/j.conbuildmat.2012.09.015.
Sharaky, I.A., Torres, L., and Sallam, H., “Experimental and analytical investigation into the flexural performance of RC beams with partially and fully bonded NSM FRP bars/stripsâ€, Composite Structures, 122, 113-126, 2015. https://doi.org/10.1016/j.compstruct.2014.11.057.
Sharaky, I.A., Torres, L., Baena, M., and Mià s, C., “An experimental study of different factors affecting the bond of NSM FRP bars in concreteâ€, Composite Structures, 99, 350-365, 2013. https://doi.org/10.1016/j.compstruct.2012.12.014.
Tang, W., Balendran, R., Nadeem, A., and Leung, H., “Flexural strengthening of reinforced lightweight polystyrene aggregate concrete beams with near-surface mounted GFRP barsâ€, Building and environment, 41, 1381-1393, 2006. https://doi.org/10.1016/j.buildenv.2005.05.029.
Wang, B., Teng, J.-G., De Lorenzis, L., Zhou, L.-M., Ou, J., Jin, W., and Lau, K., “Strain monitoring of RC members strengthened with smart NSM FRP barsâ€, Construction and Building Materials, 23, 1698-1711, 2009. https://doi.org/10.1016/j.conbuildmat.2008.07.027.
Wu, G., Dong, Z.-Q., Wu, Z.-S., and Zhang, L.-W., “Performance and parametric analysis of flexural strengthening for RC beams with NSM-CFRP barsâ€, Journal of Composites for Construction, 18, 04013051, 2013. https://doi.org/10.24200/sci.2017.4207.
Bianco, V., Barros, J.A., and Monti, G., “Bond model of NSM-FRP strips in the context of the shear strengthening of RC beamsâ€, Journal of Structural Engineering, 135, 619-631, 2009. https://doi.org/10.1007/978-3-642-17487-2_173.
Bianco, V., Monti, G., and Barros, J.A., “Design formula to evaluate the NSM FRP strips shear strength contribution to a RC beamâ€, Composites Part B: Engineering, 56, 960-971, 2014. https://doi.org/10.1016/j.compositesb.2013.09.001.
Coelho, M.R., Sena-Cruz, J.M., and Neves, L.A., “A review on the bond behavior of FRP NSM systems in concreteâ€, Construction and Building Materials, 93, 1157-1169, 2015. https://doi.org/10.1016/j.conbuildmat.2015.05.010.
Hawileh, R.A., “Nonlinear finite element modeling of RC beams strengthened with NSM FRP rodsâ€, Construction and Building Materials, 27, 461-471, 2012. https://doi.org/10.1016/j.conbuildmat.2011.07.018.
Kara, I.F., Ashour, A.F., and KöroÄŸlu, M.A., “Flexural behavior of hybrid FRP/steel reinforced concrete beamsâ€, Composite Structures, 129, 111-121, 2015. https://doi.org/10.1016/j.compstruct.2015.03.073.
Kaveh, A., Bakhshpoori, T., and Hamze-Ziabari, S., “New model derivation for the bond behavior of NSM FRP systems in concreteâ€, Iranian Journal of Science and Technology, Transactions of Civil Engineering, 41, 249-262, 2017. https://doi.org/10.1007/s40996-017-0058-z.
Seo, S.-Y., Lee, M.S., and Feo, L., “Flexural analysis of RC beam strengthened by partially de-bonded NSM FRP stripâ€, Composites Part B: Engineering, 101, 21-30, 2016. https://doi.org/10.1016/j.compositesb.2016.06.056.
Teng, J.G., Zhang, S.S., Dai, J., and Chen, J., “Three-dimensional meso-scale finite element modeling of bonded joints between a near-surface mounted FRP strip and concreteâ€, Computers & structures, 117, 105-117, 2013. https://doi.org/10.1016/j.compstruc.2012.12.002.
Zhang, S.S., and Teng, J.G., “Finite element analysis of end cover separation in RC beams strengthened in flexure with FRPâ€, Engineering structures, 75, 550-560, 2014. https://doi.org/10.1016/j.engstruct.2014.06.031.
Simulia, D.S., “Abaqus/CAE user's manualâ€, Providence, RI, Vol., 2007.
DOI: 10.28991/cej-03091126
Refbacks
- There are currently no refbacks.
Copyright (c) 2018 minu panahi

This work is licensed under a Creative Commons Attribution 4.0 International License.