Journal of Civil Engineering and Materials Application
Journal of Civil Engineering and Materials Application

Investigation of the Effect of FRP Fibers on the Seismic Retrofit of Reinforced Concrete Flat-Slab Frames with Openings under Cyclic Loading

https://doi.org/10.22034/jcema.2025.560653.1186
Volume 9, Issue 4
Autumn 2025
Pages 177-189
Journal of Civil Engineering and Materials Application

Document Type : Original Article

Author

Seyed Ali Mousavi Davoudi

Department of Engineering and Civil Engineering, Mazandaran National University of Skills,Sari, Iran.

Abstract
Flat slab systems are susceptible to brittle punching shear failure at slab–column connections, which may trigger progressive collapse. This study aims to evaluate and compare the effectiveness of fiber-reinforced polymer (FRP) strengthening with conventional concrete and steel jacketing techniques in enhancing the punching shear performance of reinforced concrete flat slabs. A five-story reinforced concrete building with a flat slab system was designed using ETABS and subsequently modeled in ABAQUS for detailed finite element analysis. Three retrofit scenarios, including FRP strengthening, concrete jacketing, and steel jacketing, were numerically investigated and compared in terms of load-carrying capacity, deformation response, and failure behavior at slab–column connections. The results indicate that FRP strengthening significantly improves punching shear resistance and stiffness while providing higher energy absorption capacity compared to the other techniques. In contrast, concrete and steel jacketing increase structural weight and exhibit less efficient performance enhancement. Overall, FRP strengthening demonstrated superior efficiency in improving structural safety and mitigating punching shear failure in flat slab systems, highlighting its practicality as an effective retrofit solution.

Keywords

Cyclic loading
Reinforced concrete frame
Retrofit
Flat slab
Finite element analysis
Subjects
[1] Dehghan K, Kazeroonian SA. Investigating the effect of size and location of openings on the stiffness and flexibility of hollow concrete slabs (Cobiax). In: Proceedings of the 4th Scientific Research Congress on New Horizons in Civil Engineering, Architecture, Culture, and Urban Management; 2016; Tehran, Iran. Available from. [View at Publisher]
[2] Deputy of Technical Affairs and Standards Development. Iranian Concrete Code (ABA) – Part 2. 2nd ed. Publication No. 120. Danesh Nama Monthly. Nos. 170–171 (Tir–Mordad). Organization for Planning and Budget; n.d. [View at Publisher]
[3] Davoudi SM, Naghipour M. The effect of slenderness ratio on modification of compressive strength of AISC code for composite columns (CFT) T-shaped with numerical (FEM) and experimental analysis. Results Mater. 2021. [View at Google Scholar]; [View at Publisher]
[4] Wang Z. Understanding seismic hazard and risk assessments: an example in the New Madrid seismic zone of the central United States. In: Proceedings of the 8th U.S. National Conference on Earthquake Engineering; 2006 Apr 18–22; San Francisco, CA, USA. Paper No. 416. [View at Google Scholar]; [View at Publisher]
[5] Committee for Revision of the Iranian Seismic Design Code. Iranian code of practice for seismic resistant design of buildings (Standard No. 2800–84). 3rd ed. Publication No. Z–253. 6th printing. Building and Housing Research Center; 2005. p.125–135. [View at Publisher]
[6] Cho YS, Seo CJ, Kang ES. A study of flat plate slab–column connections with shear plate in tall concrete building using experimental and numerical analysis. In: Proceedings of the CTBUH 2004 Seoul Conference; 2004; Seoul, South Korea. Paper No. 1704. Council on Tall Buildings and Urban Habitat. [View at Google Scholar]; [View at Publisher]
[7] Mousavi DSA, Naghipour M. Studying the buckling behavior of composite columns (CFST) by cyclic loading. J Civ Eng Mater Appl. 2019;3(4):203-213. [View at Google Scholar]; [View at Publisher]
[8] Mousavi DS, Khalilipasha MH. A Study on the Structural Effects of Bagasse Sugar Cane Stem In Structural Concrete Mixture in Sulfate and Chloride Environments. [View at Google Scholar]; [View at Publisher]
[9] Mousavi Davoudi SA, Naghipour M. Presentation of critical buckling load correction factor of AISC code on L-shaped composite columns by numerical and experimental analysis. 2020;20:1682–1702. [View at Google Scholar]; [View at Publisher]
 [10] Beheshti Aval B, Motaghi L. Effect of regional seismic hazard on the selection of retrofitting methods for defective reinforced concrete frames. Amirkabir J Civ Eng. 2017;49(3). [View at Google Scholar]; [View at Publisher]
[11] Binici B, Bayrak O. Punching shear strengthening of reinforced concrete flat plates using carbon fiber reinforced polymers. J Struct Eng (ASCE). 2003;129(9):1173–1182. [View at Google Scholar]; [View at Publisher]
[12] Mousavi Davoudi S, Neghipour M. A comparison of modal analysis of Ritz vector mode (Ritze) and Eagan vector (Eigen) based on nonlinear time history (NTH) dynamic analysis. J Struct Eng. 2020;16(4):21–32. [View at Publisher]
[13] Mousavi Davoudi S, Neghipour M. Investigation of the effective factors for eliminating the defect in the CFT columns with an asymmetric L-shaped columns by the finite element analysis. J Struct Eng. 2019;16(3):19–30. [View at Publisher]
[14] Mousavi Davoudi S, Neghipour M. Study of the behavior of composite steel columns filled with short (non-slender) concrete with (L)-shaped geometric cross section under numerical sensitivity analysis (FEM) with axial compression loading. J Struct Eng. 2019;15(4):37–50. [View at Publisher]
  • Receive Date 13 October 2025
  • Revise Date 20 November 2025
  • Accept Date 14 December 2025

Home

Guide for Authors

Submit Manuscript

Reviewers

Contact Us