EFFECTIVENESS OF STRENGTHENING OF REINFORCED CONCRETE BEAMS WITH THE USE OF COMPOSITE MATERIALS

Wide spread of RC structures in construction projects indicates the necessity of their service life prolongation. Perspective possibility to increase strength of RC structures is use of external composite tapes. The article presents theoretical research on the effectiveness of strengthening of RC bended elements with the use of composite tapes. Work also includes comparative analysis on the basis of calculations, according to normative regulations. With the use of developed algorithm parameters of stress-strain state and deformability of RC beams, strengthened with composite tapes were obtained. Study identified, that the most critical parameter was the steel bars` strain and yield point. Interesting finding of the study is the no-linearity of the strength growth of the studied elements with the increase of additional reinforcement amount. Consistent literature review was conducted, which identified the necessity to take into account different external factors and failure mode.

Abdul Halim N. H. F., C Alih S., Vafaei M. (2020). Efficiency of CFRP strips as a substitute for carbon steel stirrups in RC columns. Materials and Structures, 53(5), 1-12, doi: 10.1617/s11527-020-01566-w.
https://doi.org/10.1617/s11527-020-01566-w
Atutis M., Valivonis J., Atutis E. (2018). Experimental study of concrete beams prestressed with basalt fiber reinforced polymers. Part I: Flexural behavior and serviceability. Composite Structures, 183, 114-123. doi: 10.1016/j.compstruct.2017.01.081
https://doi.org/10.1016/j.compstruct.2017.01.081
Blikharskyy Y., Selejdak J., Kopiika N (b). Corrosion fatigue damages of rebars under loading in time. Materials, 2021, 14(12), 3416. doi:10.3390/ma14123416.
https://doi.org/10.3390/ma14123416
Blikharskyy Y., Selejdak J., Kopiika N (c). Specifics of corrosion processes in thermally strengthened rebar. Case Studies in Construction Materials, 2021, 15, e00646. doi:10.1016/j.cscm.2021.e00646
https://doi.org/10.1016/j.cscm.2021.e00646
Blikharskyy Y., Vashkevych R., Kopiika N., Bobalo T. and Blikharskyy Z (a). Calculation residual strength of reinforced con-crete beams with damages, which occurred during loading. IOP Conference Series: Materials Science and Engineering, 2021, 1021(1), 012012. doi:10.1088/1757-899X/1021/1/012012.
https://doi.org/10.1088/1757-899X/1021/1/012012
Borysiuk O., Karavan V., Sobczak-Piąstka J. (2019). Calculation of the normal section strength, rigidity and crack resistance of beams, strengthened by carbon-fiber materials. In AIP Conference Proceedings, AIP Publishing LLC. 2077(1), 020008, doi: 10.1063/1.5091869.
https://doi.org/10.1063/1.5091869
DebMallik P. (2004). Externally Bonded FRP reinforcement for strengthening RC structures. Indian concrete journal, 78(10), 54-58. Retrieved from https://www.researchgate.net/publication/294516711_Externally_bonded_FRP... .
Gideon D. A., Alagusundaramoorthy P. (2018). Flexural retrofit of RC beams using CFRP laminates. In IOP Conference Series: Materials Science and Engineering, 431(7), 072006). doi:10.1088/1757-899X/431/7/072006
https://doi.org/10.1088/1757-899X/431/7/072006
Karpiuk V., Tselikova A., Khudobych A., Kostyuk A., Karpiuk I. (2020). Study of strength, deformability property and crack resistance of beams with BFRP. Eastern-European Journal of Enterprise Technologies, 4(7-106), 42-53. doi: 10.15587/1729-4061.2020.209378.
https://doi.org/10.15587/1729-4061.2020.209378
Kramarchuk A., Ilnytskyy B., Bobalo T., Lytvyniak O. (2021). A study of bearing capacity of reinforced masonry beams with GFRP reinforcement. In IOP Conference Series: Materials Science and Engineering, 1021(1), 012018. doi:10.1088/1757-899X/1021/1/012018
https://doi.org/10.1088/1757-899X/1021/1/012018
Kvasha V. G. (2008). Calculation of the strength of normal sections of reinforced concrete beams reinforced by external glued composite reinforcement, based on the deformation models. Resource-saving materials, constructions, buildings and structures. 16 (1), 363-371. Retrieved from https://bud.nuwm.edu.ua/index.php/budres/search/index?query=&dateFromYea....
Li L., Lu J., Fang S., Liu F., Li S. (2018). Flexural study of concrete beams with basalt fibre polymer bars. Proceedings of the Institution of Civil Engineers - Structures and Buildings, 171 (7), 505-516. doi: 10.1680/jstbu.16.00204
https://doi.org/10.1680/jstbu.16.00204
Maazoun A., Matthys S., Vantomme, J. (2017). Literature review on blast protection by externally bonded FRP reinforcement. In Proceedings COST TU1207 End-of-Action Conference. Budapest, Hungary: COST TU1207. April, 2017. Retrieved from https://biblio.ugent.be/publication/8548686
Panchacharam S., Belarbi A. (2002). Torsional behavior of reinforced concrete beams strengthened with FRP composites. In First FIB Congress, 1, 01-110, Osaka, Japan, October 13-19,2002. Retrieved from  https://www.semanticscholar.org/paper/TORSIONAL-BEHAVIOR-OF-REINFORCED-C...
Petkune N, Donchev T, Hadavinia H, Wertheim D, Limbachiya M (2018) Comparison of the behaviour of steel, pure FRP and hybrid shear walls under cyclic seismic loading in aspect of stiffness degradation and energy absorption. Constr Build Mater 165:621-630. doi: 10.1016/j.conbuildmat.2017.12.013.
https://doi.org/10.1016/j.conbuildmat.2017.12.013
Rahul Raja S, Victor Sagaya Raj U, Sriram K, Rahul P.S; V.J.Vedhanayaghi (2018) Retrofitting of RC Beams using CFRP International Journal of Emerging Technology and Advanced Engineering., 8 (6), 112-114. Retrieved from https://www.researchgate.net/publication/348101978_Retrofitting_of_RC_Be...
Saljoughian A, Mostofinejad D (2020) Behavior of RC columns confined with CFRP using CSB method under cyclic axial compression. Constr Build Mater 235:117786. doi: 10.1016/j.conbuildmat.2019.117786.
https://doi.org/10.1016/j.conbuildmat.2019.117786
Smith S. T., Teng J. G. (2002). FRP-strengthened RC beams. II: Assessment of debonding strength models. Engineering Structures, 24(4), 397-417. doi: 10.1016/S0141-0296(01)00106-7.
https://doi.org/10.1016/S0141-0296(01)00106-7
Teng J. G., Smith S. T., Yao J., Chen J. F. (2003). Intermediate crack-induced debonding in RC beams and slabs. Construction and Building Materials, 17(6-7), 447-462. doi:10.1016/S0950-0618(03)00043-6.
https://doi.org/10.1016/S0950-0618(03)00043-6
Xu Y, Huang J (2020) Cyclic performance of corroded reinforced concrete short columns strengthened using carbon fiber-reinforced polymer. Constr Build Mater. 247, 118548. doi: 10.1016/j.conbuildmat.2020.118548
https://doi.org/10.1016/j.conbuildmat.2020.118548
Zhu M., Ueda T., Zhu, J. H. (2020). Generalized evaluation of bond behavior of the externally bonded FRP reinforcement to concrete. Journal of Composites for Construction, 24(6), 04020066. doi: 10.1061/(ASCE)CC.1943-5614.0001081
https://doi.org/10.1061/(ASCE)CC.1943-5614.0001081