Behavior of Fire-damaged RC Beams After Strengthening with Various Techniques

Asser Elsheikh, Hadeal H. Alzamili


High temperatures during a fire can significantly degrade the structural capacity of concrete. However, in many cases, it is possible to restore and strengthen fire-damaged concrete rather than completely rebuild damaged structures. The study considered two types of concrete (normal 25 MPa and high-strength 65 MPa) with two types of strengthening techniques: carbon-fiber-reinforced polymers (CFRP) sheets with different thicknesses of 1.5 and 2.5 mm and slurry-infiltrated fibrous concrete (SIFCON) jacketing with different fiber sizes of 20 and 30 mm. The numerical simulations and analyses were conducted to capture the complex behavior of fire-damaged concrete members (beams). A fire-damaged concrete beam subjected to an extreme or critical fire Exposure time (2 hours) was evaluated and modified using a finite element simulation approach. The simulation process included three stages: the first, subjecting the concrete beam to thermal loading; the second, reflecting the fire distribution map to another model of applying mechanical loading; and the third, involving the application of strengthening to the damaged model. The results showed that the strengthening using CFRP with a thickness of 2.5 improved the load-carrying capacity compared with SIFCON in both types of concrete. 200% improvement for the normal-strength concrete beam and a 136% improvement for the high-strength concrete beam, compared to the damaged beams.


Doi: 10.28991/CEJ-2024-010-01-012

Full Text: PDF


RC Beam; CFRP; SIFCON; Fire.


Liu, T., Wang, H., Zou, D., Long, X., Miah, M. J., & Li, Y. (2023). Strength recovery of thermally damaged high-performance concrete subjected to post-fire carbonation curing. Cement and Concrete Composites, 143, 105273. doi:10.1016/j.cemconcomp.2023.105273.

Abdalla, A. A., & Karim, D. F. R. (2022). Repairing Materials for Different Post Fire - Damaged Structural Concrete Members: A Critical Review. Construction, 2(2), 56–64. doi:10.15282/construction.v2i2.8660.

Agrawal, A., & Kodur, V. K. R. (2020). A Novel Experimental Approach for Evaluating Residual Capacity of Fire Damaged Concrete Members. Fire Technology, 56(2), 715–735. doi:10.1007/s10694-019-00900-1.

Alzamili, H. H., & Elsheikh, A. M. (2023). Performance of reinforced concrete elements retrofitted with SIFCON under elevated temperatures. Al-Qadisiyah Journal for Engineering Sciences, 16(1), 53–57. doi:10.30772/qjes.v16i1.969.

Zhou, J., & Wang, L. (2019). Repair of Fire-Damaged Reinforced Concrete Members with Axial Load: A Review. Sustainability (Switzerland), 11(4), 963. doi:10.3390/su11040963.

Naqvi, S. A. (2021). Flexural Strengthening of Two-Way Slabs Using CFRP External Laminates. Master Thesis, University of Texas, Arlington, United States.

Abadel, A. A., Abbas, H., Alshaikh, I. M. H., sennah, K., Tuladhar, R., Altheeb, A., & Alamri, M. (2023). Experimental study on the effects of external strengthening and elevated temperature on the shear behavior of ultra-high-performance fiber-reinforced concrete deep beams. In Structures (Vol. 49, pp. 943–957). Elsevier. doi:10.1016/j.istruc.2023.02.004.

Al-Rousan, R. Z. (2023). Impact of Internal CFRP strips on the flexural behavior of heat-damaged reinforced concrete beams. Heliyon, 9(6). doi:10.1016/j.heliyon.2023.e17145.

Mohammadi-Firouz, R., Pereira, E. N. B., & Barros, J. A. O. (2023). Experimental assessment of the thermo-mechanical bond behavior of NSM CFRP with cement-based adhesives. Construction and Building Materials, 364, 129980. doi:10.1016/j.conbuildmat.2022.129980.

Marid, H., & Vahidi, E. K. (2023). Experimental study on flexural behavior of reinforced lightweight concrete beams strengthening with a slurry infiltrated fiber concrete (SIFCON). Asian Journal of Civil Engineering, 1–13. doi:10.1007/s42107-023-00879-9.

Carrillo, J., Ramirez, J., & Lizarazo-Marriaga, J. (2019). Modulus of elasticity and Poisson’s ratio of fiber-reinforced concrete in Colombia from ultrasonic pulse velocities. Journal of Building Engineering, 23, 18–26. doi:10.1016/j.jobe.2019.01.016.

Abd-Ali, M. S., & Essa, A. A. A. (2019). Mechanical properties of slurry infiltrated fibrous concrete (SIFCON) with variation steel fiber ratios and silica fume. Journal of Advanced Research in Dynamical and Control Systems, 11, 1863–1872.

Servadei, F., Zoli, L., Galizia, P., Piancastelli, A., & Sciti, D. (2023). Processing and characterization of ultra-high temperature ceramic matrix composites via water based slurry impregnation and polymer infiltration and pyrolysis. Ceramics International, 49(1), 1220–1229. doi:10.1016/j.ceramint.2022.09.100.

Adnan, N., Alwash, N. A., & Kadhum, M. M. (2023). Experimental Study on the Behavior of Axially Loaded Reinforced Concrete Square Columns Strengthened with SIFCON Shell. E3S Web of Conferences, 427, 2019. doi:10.1051/e3sconf/202342702019.

Khamees, S. S., Kadhum, M. M., & Alwash, N. A. (2020). Experimental and numerical investigation on the axial behavior of solid and hollow SIFCON columns. SN Applied Sciences, 2(6), 1–15. doi:10.1007/s42452-020-2907-9.

Tiwary, A. K., & Bhatia, S. (2020). Retrofitting techniques for reinforced and sustainable concrete column. Journal of Green Engineering, 10(9), 6858–6870.

Vritesh, M. V., & Asish, S. (2021). A Comparative Analysis on the Methods of Strengthening Isolated Reinforced Concrete Columns. IOP Conference Series: Materials Science and Engineering, 1203(2), 022037. doi:10.1088/1757-899x/1203/2/022037.

Suntharalingam, T., Gatheeshgar, P., Upasiri, I., Poologanathan, K., Nagaratnam, B., Rajanayagam, H., & Navaratnam, S. (2021). Numerical study of fire and energy performance of innovative light-weight 3d printed concrete wall configurations in modular building system. Sustainability (Switzerland), 13(4). doi:10.3390/su13042314.

Abdulghani, A. W., & Jaafer, A. A. (2021). Comparative Numerical Study between /Steel Fiber Reinforced Concrete and SIFCON on Beam-Column Joint Behavior. Materials Science Forum, 1021, 138–149. doi:10.4028/

Salehi, R., Akbarpour, A., & Shalbaftabar, A. (2020). Fire Evaluation of RC Frames Strengthened with FRPs Using Finite Element Method. American Journal of Engineering and Applied Sciences, 13(4), 610–626. doi:10.3844/ajeassp.2020.610.626.

Mohammed, A. S. A., Abdullah, A. S. A., & Zayed, A. N. A. (2021). Strengthening of Reinforced Concrete Two-Way Slabs Using FRP. Reinforced Concrete Research Group, Menoufia University, Al Minufiyah, Egypt.

Yoo, S. J., Yuan, T. F., Hong, S. H., & Yoon, Y. S. (2020). Effect of strengthening methods on two-way slab under low-velocity impact loading. Materials, 13(24), 1–16. doi:10.3390/ma13245603.

Hashad, M., Elgendy, M., & Essam, M. Rehabilitation of reinforced concrete slabs using steel. Reinforced Concrete Research Group, Menoufia University, Al Minufiyah, Egypt.

Warwar, R. S., & Said, A. I. (2021). Flexural Behavior of Reinforced Concrete Beams Covered by Gypsum Layers and Exposed to Elevated Temperatures. E3S Web of Conferences, 318, 03005. doi:10.1051/e3sconf/202131803005.

Alzamili, H. H., & Elsheikh, A. M. (2023). Numerical Study of the Behavior of RC Beam At High Temperatures. Building and Reconstruction, 110(6), 58–72. doi:10.33979/2073-7416-2023-110-6-58-72.

Panahi, H., & Genikomsou, A. S. (2022). Comparative Investigation of Concrete Plasticity Models for Nonlinear Finite-Element Analysis of Reinforced Concrete Specimens. Practice Periodical on Structural Design and Construction, 27(2), 4021083. doi:10.1061/(asce)sc.1943-5576.0000670.

Raza, A., Khan, Q. U. Z., & Ahmad, A. (2019). Numerical investigation of load-carrying capacity of GFRP-reinforced rectangular concrete members using CDP model in Abaqus. Advances in Civil Engineering, 2019. doi:10.1155/2019/1745341.

Michał, S., & Andrzej, W. (2015). Calibration of the CDP model parameters in Abaqus. Advances in Structural Engineering and Mechanics (ASEM15), 25-29 August, 2015, Incheon, Korea.

Le Minh, H., Khatir, S., Abdel Wahab, M., & Cuong-Le, T. (2021). A concrete damage plasticity model for predicting the effects of compressive high-strength concrete under static and dynamic loads. Journal of Building Engineering, 44, 103239. doi:10.1016/j.jobe.2021.103239.

Bakhti, R., Benahmed, B., Laib, A., & Alfach, M. T. (2022). New approach for computing damage parameters evolution in plastic damage model for concrete. Case Studies in Construction Materials, 16, 834. doi:10.1016/j.cscm.2021.e00834.

Nastri, E., & Todisco, P. (2022). Macromechanical Failure Criteria: Elasticity, Plasticity and Numerical Applications for the Non-Linear Masonry Modelling. Buildings, 12(8), 1245. doi:10.3390/buildings12081245.

Anas, S. M., Alam, M., & Shariq, M. (2023). Behavior of two-way RC slab with different reinforcement orientation layouts of tension steel under drop load impact. Materials Today: Proceedings, 87, 30–42. doi:10.1016/j.matpr.2022.08.509.

Habeeb Albo Sabar, A., & Mansour Kadhum, M. (2022). Numerical modeling of the experimental test for shear strengthened of fire damaged high strength lightweight RC beams with SIFCON jacket. Periodicals of Engineering and Natural Sciences (PEN), 10(2), 512. doi:10.21533/pen.v10i2.2984.

Cai, B., Li, B., & Fu, F. (2020). Finite Element Analysis and Calculation Method of Residual Flexural Capacity of Post-fire RC Beams. International Journal of Concrete Structures and Materials, 14(1), 58. doi:10.1186/s40069-020-00428-7.

Elsheikh, A., & Alzamili, H. H. (2023). Post Fire Behavior of Structural Reinforced Concrete Member (Slab) Repairing with Various Materials. Civil Engineering Journal (Iran), 9(8), 2012–2031. doi:10.28991/CEJ-2023-09-08-013.

Full Text: PDF

DOI: 10.28991/CEJ-2024-010-01-012


  • There are currently no refbacks.

Copyright (c) 2024 hadeal hakim alzamili

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