Structural Mechanics of Engineering Constructions and BuildingsStructural Mechanics of Engineering Constructions and BuildingsСтроительная механика инженерных конструкций и сооружений1815-52352587-8700Peoples’ Friendship University of Russia named after Patrice Lumumba (RUDN University)3722210.22363/1815-5235-2023-19-5-502-509HXKXDMAnalytical and numerical methods of analysis of structuresАналитические и численные методы расчета конструкцийResearch ArticlePerformance of reinforced concrete elements strengthened with carbon fiber CFRP at elevated temperaturesХарактеристики железобетонных элементов, усиленных углепластиком CFRP, при повышенных температурахhttps://orcid.org/0000-0001-8109-3381AlzamiliHadeal H.АльзамилиХадиль Хаким

PhD student, Department of Civil Engineering, Academy of Engineering

аспирант департамента строительства, инженерная академия

HadealHakim8@gmail.comhttps://orcid.org/0000-0002-1212-2924ElsheikhAsser M.ЭльшейхАссер Мохамед

Assistant professor, Department of Civil Engineering, Academy of Engineering, RUDN University; Assistant professor, Department of Civil Engineering, Mansoura University

кандидат технических наук, доцент департамента строительства, инженерная академия, Российский университет дружбы народов; доцент департамента строительства, Университет Мансуры

elsheykh_am@pfur.ruRUDN UniversityРоссийский университет дружбы народовMansoura UniversityМансура университет15122023195VOL 19, NO5 (2023)ТОМ 19, №5 (2023)50250928122023Copyright ©; 2023, Alzamili H.H., Elsheikh A.M.Copyright ©; 2023, Альзамили Х.Х., Эльшейх А.М.2023Alzamili H.H., Elsheikh A.M.Альзамили Х.Х., Эльшейх А.М.https://creativecommons.org/licenses/by-nc/4.0https://journals.rudn.ru/structural-mechanics/article/view/37222

The importance of the research topic is established by the problems that occur in structural buildings when exposed to fire accidents, where the concrete loses much part of its mechanical properties and therefore becomes out of service. Because reconstruction of damaged buildings has a high financial cost, it is necessary to focus on the restoration of damaged concrete members with performant techniques and proven efficiency in terms of increasing the strength of concrete and its resistance to high temperatures. The authors conduct a numerical investigation on the use of carbon fiber-reinforced polymer sheeting CFRP to restore various structural concrete elements such as beams, columns, and slabs damaged in fire accidents for two types of normal and high-strength concrete, in addition to studying the behavior of concrete after strengthening it with CFRP sheets. The results by showed that load capacity, stiffness index, and absorption energy index have been improved

Актуальность темы исследования обусловлена проблемами, возникающими в несущих зданиях при пожарах, когда бетон теряет большую часть своих механических свойств и, следовательно, выходит из строя. Поскольку реконструкция поврежденных зданий требует высоких финансовых затрат, необходимо сосредоточиться на восстановлении поврежденных бетонных элементов с использованием надежных методов и доказанной эффективности с точки зрения восстановления прочности бетона и повышения устойчивости к высоким температурам. В исследовании численно исследуется использование углепластика CFRP, для восстановления различных структурных бетонных элементов, таких как балки, колонны и плиты, поврежденных в результате пожара, для двух типов нормального и высокопрочного бетона, а также изучается поведение бетона после укрепления его листами углепластика. Результаты показали, что несущая способность, индекс жесткости и индекс энергии поглощения были улучшены при использовании углепластика по сравнению с неповрежденными и поврежденными огнем элементами.

columnslabcarbon fiberconcreteбалкаколоннаплитауглепластикбетонMiliozzi A., Chieruzzi M., Torre L. Experimental investigation of a cementitious heat storage medium incorporating a solar salt/diatomite composite phase change material. Applied Energy. 2019;250:1023-1035. http://doi.org/10.1016/j.apenergy.2019.05.090Ni S., Gernay T. Predicting residual deformations in a reinforced concrete building structure after a fire event. Engineering Structures. 2020;202:109853. http://doi.org/10.1016/j.engstruct.2019.109853Sharma N.K., Kumar P., Kumar S., Thomas B.S., Gupta R.C. Properties of concrete containing polished granite waste as partial substitution of coarse aggregate. Construction and Building Materials. 2017;151:158-163. http://doi.org/10.1016/j.conbuildmat.2017.06.081Kodur V. Properties of concrete at elevated temperatures. ISRN Civil Engineering. 2014(2):1-15. http://doi.org/10.1155/2014/468510Yonggui W., Shuaipeng L., Hughes P., Yuhui F. Mechanical properties and microstructure of basalt fibre and nano-silica reinforced recycled concrete after exposure to elevated temperatures. Construction and Building Materials. 2020;247(7): 118561. http://doi.org/10.1016/j.conbuildmat.2020.118561Xie J., Zhang Z., Lu Z., Sun M. Coupling effects of silica fume and steel-fiber on the compressive behaviour of recycled aggregate concrete after exposure to elevated temperature. Construction and Building Materials. 2018;184:752-764. http://doi.org/10.1016/j.conbuildmat.2018.07.035Khaliq W., Waheed F. Mechanical response and spalling sensitivity of air entrained high-strength concrete at elevated temperatures. Construction and Building Materials. 2017;150:747-757. http://doi.org/10.1016/j.conbuildmat.2017. 06.039Chen G.M., He Y.H., Yang H., Chen J.F., Guo Y.C. Compressive behavior of steel fiber reinforced recycled aggregate concrete after exposure to elevated temperatures. Construction and Building Materials. 2014;71:1-15. https://doi.org/10.1016/j.conbuildmat.2014.08.012Eidan J., Rasoolan I., Rezaeian A., Poorveis D. Residual mechanical properties of polypropylene fiber-reinforced concrete after heating. Construction and Building Materials. 2019;198:195-206. http://doi.org/10.1016/j.conbuildmat. 2018.11.209Lau A., Anson M. Effect of high temperatures on high performance steel fibre reinforced concrete. Cement and concrete research. 2006;36(9):1698-1707. http://doi.org/10.1016/j.cemconres.2006.03.024Moghadam M.A., Izadifard R.A. Effects of steel and glass fibers on mechanical and durability properties of concrete exposed to high temperatures. Fire Safety Journal. 2020;113(7):102978. http://doi.org/10.1016/j.firesaf.2020. 102978Naqi A.W., Al-zuhairi A.H. Nonlinear Finite Element Analysis of RCMD Beams with Large Circular Opening Strengthened with CFRP Material. Journal of Engineering. 2020;26(11):170-183. http://doi.org/10.31026/j.eng.2020.11.11Banerji S., Kodur V. Effect of temperature on mechanical properties of ultra-high performance concrete. Fire and Materials. 2022;46(1):287-301. http://doi.org/10.1002/fam.2979Abadel A.A., Alharbi Y.R. Confinement effectiveness of CFRP strengthened ultra-high performance concrete cylinders exposed to elevated temperatures. Materials Science-Poland. 2021;39(4):478-490. http://doi.org/10.2478/ msp-2021-0040Mazzotti C., Bilotta A., Carloni C., Ceroni F., D’Antino T., Nigro E., Pellegrino C. Bond between EBR FRP and concrete. Design Procedures for the Use of Composites in Strengthening of Reinforced Concrete Structures: 2016; State-ofthe-Art Report of the RILEM Technical Committee 234-DUC. Springer Publ.; 2016:39-96. http://doi.org/10.1007/978-94017-7336-2_3Ashteyat A.M., Obaidat Y.T., Al-Btoush A.Y., Hanandeh S. Experimental and numerical study of strengthening and repairing heat-damaged RC circular column using hybrid system of CFRP. Case Studies in Construction Materials. 2021;15(6):e00742. http://doi.org/10.1016/j.cscm.2021.e00742Shehata I.A., Carneiro L.A., Shehata L.C. Strength of short concrete columns confined with CFRP sheets. Materials and structures. 2002;35:50-58. http://doi.org/10.1617/13686Mhanna H.H., Hawileh R.A., Abdalla J.A. Shear strengthening of reinforced concrete beams using CFRP wraps. Procedia Structural Integrity, 2019;17:214-221. http://doi.org/10.1016/j.prostr.2019.08.029Elsheikh A., Alzamili H.H. Post Fire Behavior of Structural Reinforced Concrete Member (Slab) Repairing with Various Materials. Civil Engineering Journal. 2023;9(8):2012-2031. http://doi.org/10.28991/CEJ-2023-09-08-013Hashin Z. Failure criteria for unidirectional fiber composites. Journal of Applied Mechanics. 1980;47(2):329-334. https://doi.org/10.1115/1.3153664Hashin Z., Rotem A. A fatigue failure criterion for fiber reinforced materials. Journal of Composite Materials. 1973;7(4):448-64. http://doi.org/10.1177/002199837300700404Hochard C., Aubourg P.A., Charles J.P. Modelling of the mechanical behaviour of woven-fabric CFRP laminates up to failure. Composites science and technology. 2001;61(2):221-230.