Flexural Strengthening of Reinforced Concrete Beams with Prestressed L-Shaped Sections: A Numerical Investigation

Subject Areas : Journal of Building Information Modeling

Mohammad Reza Khastkhodaei ^{1 *} , Arash Totonchi ² , Seyed Ahmad Jenabali Jahromi ³ , Abdeloued Tounsi ⁴

1 - Department of Civil Engineering, Apadana Institute of Higher Education, Shiraz, Iran
2 - Department of Civil Engineering, Apadana Institute of Higher Education, Shiraz, Iran
3 - Department of Civil Engineering, Apadana Institute of Higher Education, Shiraz, Iran.
4 - Material and Hydrology Laboratory, University of Sidi Bel Abbes, Faculty of Technology, Civil Engineering Department, Algeria; Department of Civil and Environmental Engineering, King Fahd University of Petroleum & Minerals, 31261 Dhahran, Eastern Province, Saudi Arabia

Received: 2025-08-07 Accepted : 2025-09-27 Published : 2025-10-08

Keywords: Strengthening, Reinforced Concrete, Prestressed Concrete Beam, Flexural Strength, Numerical Modeling, Finite Element Method.,

Abstract :

This study introduces and numerically validates a novel method for the flexural strengthening of reinforced concrete (RC) beams using prefabricated, L-shaped prestressed concrete sections. A Finite Element model was developed in Abaqus and validated against existing experimental data for an unstrengthened RC beam. A comprehensive parametric study was then conducted to assess the performance of the strengthened system, focusing on the effects of prestress level and tendon arrangement. The results demonstrate the exceptional efficacy of the proposed technique. The beam's flexural capacity was significantly increased, with the optimal configuration showing a 428.7% enhancement in yield moment compared to the reference beam. Furthermore, the method substantially improves the structure's ductility and energy dissipation capacity, with inelastic energy dissipation increasing by up to 59.9% and damage-related energy dissipation by up to 191%. A direct comparison revealed that the proposed method's performance is approximately 2.5 times greater than strengthening with advanced Ultra-High Performance Fiber Reinforced Concrete (UHPFRC) jackets. This numerical proof-of-concept confirms that the proposed technique is a highly promising and efficient solution for structural retrofitting.

References:

Abbassi, K., Janghorban, M., Javanmardi, F., & Mobasseri, S. (2023). Feasibility study of femur bone with continuum model. Journal of Medical Engineering & Technology, 47(7), 355-366. https://doi.org/https://doi.org/10.1080/03091902.2024.2336512
Abdolpour, H., & Sawicki, B. (2025). Analyzing fracture mechanism of high performance concrete using concrete damage plasticity model. Archives of Civil and Mechanical Engineering, 25(5), 241. https://doi.org/https://doi.org/10.1007/s43452-025-01287-3
Al-Ashmawy, A. M., Shallan, O., Sakr, T. A., & Abd-EL-Mottaleb, H. E. (2023). Numerical investigations of reinforcement concrete beams with different types of FRP bars. Structural engineering and mechanics: An international journal, 88(6), 599-608. https://doi.org/https://doi.org/10.12989/sem.2023.88.6.599
Al Khaffaf, I., Hawileh, R. A., Sahoo, S., Abdalla, J. A., & Kim, J. H. (2025). Toward carbon-neutral construction: A review of zero-carbon concrete. Journal of Building Engineering, 99, 111578. https://doi.org/https://doi.org/10.1016/j.jobe.2024.111578
Althoey, F., Ansari, W. S., Sufian, M., & Deifalla, A. F. (2023). Advancements in low-carbon concrete as a construction material for the sustainable built environment. Developments in the built environment, 16, 100284. https://doi.org/https://doi.org/10.1016/j.dibe.2023.100284
Attari, N., Youcef, Y. S., & Amziane, S. (2019). Seismic performance of reinforced concrete beam–column joint strengthening by frp sheets. Structures, 20, 353-364. https://doi.org/https://doi.org/10.1016/j.istruc.2019.04.007
Bouakaz, K., Daouadji, T. H., Meftah, S., Ameur, M., Tounsi, A., & Bedia, E. A. (2014). A numerical analysis of steel beams strengthened with composite materials. Mechanics of Composite Materials, 50(4), 491-500. https://doi.org/https://doi.org/10.1007/s11029-014-9435-x
Chen, Z., Xu, R., Ling, Z., Liang, Y., Lu, S., & Qin, L. (2023). Experimental and numerical analysis of shear performance of reinforced concrete beams with double openings. Archives of Civil and Mechanical Engineering, 23(3), 195. https://doi.org/https://doi.org/10.1007/s43452-023-00745-0
Elsalakawy, T. S., El-Diasity, M., Mounir Naguib, M., & Hamdy, M. (2025). Effect of vertical irregularity of concrete frame systems on the seismic response modification factor. Computers and Concrete, An International Journal, 36(5), 127-140. https://doi.org/https://doi.org/10.12989/cac.2025.36.2.127
Esmaeeli, E., Barros, J. A., Sena-Cruz, J., Fasan, L., Prizzi, F. R. L., Melo, J., & Varum, H. (2015). Retrofitting of interior RC beam–column joints using CFRP strengthened SHCC: cast-in-place solution. Composite Structures, 122, 456-467. https://doi.org/https://doi.org/10.1016/j.compstruct.2014.12.012
Favier, A., De Wolf, C., Scrivener, K., & Habert, G. (2018). A sustainable future for the European Cement and Concrete Industry: Technology assessment for full decarbonisation of the industry by 2050.
Gergely, J., Pantelides, C. P., & Reaveley, L. D. (2000). Shear strengthening of RCT-joints using CFRP composites. Journal of composites for construction, 4(2), 56-64. https://doi.org/https://doi.org/10.1061/(ASCE)1090-0268(2000)4:2(56
Gkournelos, P., Triantafillou, T., & Bournas, D. (2021). Seismic upgrading of existing reinforced concrete buildings: A state-of-the-art review. Engineering Structures, 240, 112273. https://doi.org/https://doi.org/10.1016/j.engstruct.2021.112273
Habibi, M., Mobasseri, S., Zare, A., & Souriaee, V. (2022). Drug delivery with therapeutic lens for the glaucoma treatment in the anterior eye chamber: a numerical simulation. Biomedical Engineering Advances, 3, 100032. https://doi.org/https://doi.org/10.1016/j.bea.2022.100032
Hadi, M. N., & Tran, T. M. (2014). Retrofitting nonseismically detailed exterior beam–column joints using concrete covers together with CFRP jacket. Construction and Building Materials, 63, 161-173. https://doi.org/https://doi.org/10.1016/j.conbuildmat.2014.04.019
Hajihashemi, A. (2008). Hashemi, A. H. (2008). Strengthening of reinforced concrete beams using prestressed CFRP materials by the near-surface mounted (NSM) method [Master's thesis, Isfahan University of Technology]. Isfahan University of Technology]. Iran.
Hassani Tabar, H., Salehi YaneSari, M., Hosseinali Beygi, M., & Teymouri Yanehsari, M. (2014). Experimental investigation of flexural behavior of reinforced concrete beams strengthened with prestressed CFRP plates 8th National Congress on Civil Engineering, Babol, Iran.
He, C., Yu, Y., Li, G., Zhuge, Y., Zeng, J.-J., & Zhang, M. (2025). Experimental study and finite element simulation of innovative steel buckling restrained braces with three yielding stages. Structures,
International, A. (2018). ASTM A416 / A416M-18, Standard Specification for Steel Strand, Uncoated Seven-Wire for Prestressed Concrete, ASTM International, West Conshohocken, PA,. In. United States.
Islam, A. S. (2020). Computer aided failure prediction of reinforced concrete beam. Computers and Concrete, An International Journal, 25(1), 67-73. https://doi.org/https://doi.org/10.12989/cac.2020.25.1.067
Jankowiak, T., & Lodygowski, T. (2005). Identification of parameters of concrete damage plasticity constitutive model. Foundations of civil and environmental engineering, 6(1), 53-69.
Kabashi, N., Muhaxheri, M., Krasniqi, E., Murati, Y., & Latifi, F. (2025). Advancements in Fiber-Reinforced Polymer (FRP) Retrofitting Techniques for Seismic Resilience of Reinforced Concrete Structures. Buildings, 15(4), 587. https://doi.org/https://doi.org/10.3390/buildings15040587
Karbhari, V. M. (2001). Materials considerations in FRP rehabilitation of concrete structures. Journal of materials in civil engineering, 13(2), 90-97. https://doi.org/https://doi.org/10.1061/(ASCE)0899-1561(2001)13:2(90
Kim, K., Lee, B.-G., Jung, J.-S., & Lee, K.-S. (2025). Seismic performance evaluation of reinforced concrete columns using finite element-based nonlinear dynamic analysis. Structures,
Laib, S., Meftah, S. A., Youzera, H., Ziane, N., & Tounsi, A. (2021). Vibration and damping characteristics of the masonry wall strengthened with bonded fibre composite patch with viscoelastic adhesive layer. Computers and Concrete, 27(3), 253-268. https://doi.org/https://doi.org/10.12989/cac.2021.27.3.253
Lampropoulos, A., Paschalis, S. A., Tsioulou, O., & Dritsos, S. E. (2016). Strengthening of reinforced concrete beams using ultra high performance fibre reinforced concrete (UHPFRC). Engineering Structures, 106, 370-384. https://doi.org/https://doi.org/10.1016/j.engstruct.2015.10.042
Lewiński, P. M., & Więch, P. P. (2020). Finite element model and test results for punching shear failure of RC slabs. Archives of Civil and Mechanical Engineering, 20(2), 36. https://doi.org/https://doi.org/10.1007/s43452-020-00037-x
Ma, C., Wang, D., & Wang, Z. (2017). Seismic retrofitting of full-scale RC interior beam-column-slab subassemblies with CFRP wraps. Composite Structures, 159, 397-409. https://doi.org/https://doi.org/10.1016/j.compstruct.2016.09.094
Mirzaee, A., Torabi, A., & Totonchi, A. (2021). Experimental study on the behavior of reinforced concrete beam boosted by a post-tensioned concrete layer. Computers and Concrete, 28(6), 549-557. https://doi.org/https://doi.org/10.12989/cac.2021.28.6.549
Mobasseri, S., & Janghorban, M. (2024). Non-homogeneous model for studying femur bone implants with considering defects. International Journal of Modelling and Simulation, 1-11. https://doi.org/https://doi.org/10.1080/02286203.2024.2392217
Mobasseri, S., Karami, B., Sadeghi, M., & Tounsi, A. (2022). Bending and torsional rigidities of defected femur bone using finite element method. Biomedical Engineering Advances, 3, 100028. https://doi.org/https://doi.org/10.1016/j.bea.2022.100028
Mobasseri, S., & Mobasseri, M. (2016, 2016/7/28). A Comparative Study Between ABS and Disc Brake System Using Finite Element Method International Conference on researches in Science and Engineering, Turkey.
Mobasseri, S., Sadeghi, M., Janghorban, M., & Tounsi, A. (2020). Approximated 3D non-homogeneous model for the buckling and vibration analysis of femur bone with femoral defects. Biomaterials and Biomechanics in Bioengineering, 5(1), 25-35. https://doi.org/https://doi.org/10.12989/bme.2020.5.1.025
Mobasseri, S., & Soltani, H. (2013). Impact of driving style on fuel consumption. Nature and Science, 11, 87-89.
Mobasseri, S., Zare, A., & Janghorban, M. (2024). Dynamic behavior of dragonfly wing veins including the role of hemolymph. Journal of Mechanics in Medicine and Biology, 24(04), 2350093. https://doi.org/https://doi.org/10.1142/S0219519423500938
Nawy, E. G. (1988). Prestressed concrete. A fundamental approach. Prentice Hall.
Ni, Y., Ma, Y., Lin, H., Zhang, H., & Zhuo, Y. (2025). Finite element model updating of existing bridge structures based on measured data and deep learning method. Structures,
Raza, S., Khan, M. K., Menegon, S. J., Tsang, H.-H., & Wilson, J. L. (2019). Strengthening and repair of reinforced concrete columns by jacketing: State-of-the-art review. Sustainability, 11(11), 3208. https://doi.org/https://doi.org/10.3390/su11113208
Sadeghi, V., & Hesami, S. (2018). Finite element investigation of the joints in precast concrete pavement. Computers and Concrete, An International Journal, 21(5), 547-557. https://doi.org/https://doi.org/10.12989/cac.2018.21.5.547
Shahbazpanahi, S., & Manie, S. (2006). A review of strengthening methods for reinforced concrete beams 1st National Conference on Urban Civil Engineering, Sanandaj, Iran.
Shakor, P., Gowripalan, N., & Rasouli, H. (2021). Experimental and numerical analysis of 3D printed cement mortar specimens using inkjet 3DP. Archives of Civil and Mechanical Engineering, 21(2), 58. https://doi.org/https://doi.org/10.1007/s43452-021-00209-3
Sharif, A., Al-Sulaimani, G., Basunbul, I., Baluch, M., & Ghaleb, B. (1994). Strengthening of initially loaded reinforced concrete beams using FRP plates. Structural Journal, 91(2), 160-168.
Singh, S. B., & Murty, C. (2024). RC Structures Strengthened with FRP for Earthquake Resistance. Springer. https://doi.org/https://doi.org/10.1007/978-981-97-0102-5
Sümer, Y., & Aktaş, M. (2015). Defining parameters for concrete damage plasticity model. Challenge Journal of Structural Mechanics, 1(3), 149-155. https://doi.org/https://doi.org/10.20528/cjsmec.2015.07.023
Systèmes, D. (2016). Abaqus 2016 Documentation.© Dassault Systemes. In.
Tan, J.-K., Zheng, W.-L., Wang, Y.-H., Su, M.-N., Zhao, L., Zhang, Y.-H., Feng, Y., & Chen, D.-X. (2025). Finite element modelling and design of concrete wind turbine towers subjected to combined compression and bending. Structures,
Wang, B., Chen, P., Jiang, H., & Wang, J. (2024). Performance of steel-plate-reinforced concrete composite walls in tall structures. Proceedings of the Institution of Civil Engineers-Civil Engineering, 177(3), 118-125. https://doi.org/https://doi.org/10.1680/jcien.23.00167
.