Amirkabir Journal of Civil Engineering

Amirkabir Journal of Civil Engineering

Investigation of Structural Behavior in Hybrid Reinforced Concrete Frames with Steel and GFRP Bars

Document Type : Research Article

Authors
Fahimeh Maleki
Omid Rezaifar
Ali Kheyroddin
Faculty of Civil Engineering. Semnan University. Semnan, Iran
10.22060/ceej.2026.24097.8258
Abstract
The use of Fiber-Reinforced Polymer (FRP) bars as a solution to prevent corrosion in structures such as beams, slabs, bridges, and multi-story parking structures is gaining prominence. However, due to their linear-elastic behavior, brittle failure, and low modulus of elasticity, concerns have been raised regarding their structural performance. This study presents a numerical investigation into the behavior of ten one-story one-span reinforced concrete frames subjected to pushover analysis using ABAQUS software. The primary objective is to evaluate and compare the performance of frames reinforced with various types of FRP bars (in beams, columns, or both) against conventionally steel-reinforced concrete frames. The results indicate that using CFRP bars in a one-story frame increases the maximum lateral load and corresponding story drift by approximately 63% and 32%, respectively, compared to the steel-reinforced frame. Conversely, the use of GFRP and AFRP bars leads to a reduction in these parameters. Optimal performance was observed when GFRP and AFRP bars were used exclusively in the beams; in this configuration, the maximum lateral load increased by approximately 18% and 16%, respectively, compared to their use in the columns of the investigated hybrid frames. Furthermore, to examine the trend of crack initiation and propagation, the maximum plastic strain was compared at different drift levels.
Keywords
Hybrid RC Frames
Finite Element Method
FRP Bars
Drift
Cracking
Subjects
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Amirkabir Journal of Civil Engineering
Volume 58, Issue 3
2026
Pages 335-352