Optimizing CFRP Reinforcement in Concrete Beams: A Comparative Analysis of Internal Embedment vs. External Bonding on Mechanical Behavior

Abstract:

Concrete, often conceptualized as an inert construction material, is fundamentally a dynamic composite that undergoes continuous physicochemical transformations throughout its service life, governed by natural degradation processes and mechanical aging. Despite its widespread utility, concrete’s quasi-brittle behavior, characterized by low tensile strength and susceptibility to abrupt failure under traction-dominated loading regimes, remains a critical limitation in structural engineering. To address these intrinsic vulnerabilities, the rehabilitation of concrete infrastructure has emerged as a pivotal research domain, with advanced retrofitting techniques focusing on enhancing tensile performance and transitioning failure modes from brittle to ductile. Among these, externally bonded reinforcement (EBR) using fiber-reinforced polymer (FRP) composites has gained prominence as a high-efficacy solution for augmenting load-bearing capacity and structural resilience. This study employs a parametric finite element analysis (FEA) framework in Abaqus/CAE to systematically evaluate the mechanical efficacy of two distinct carbon fiber-reinforced polymer (CFRP) retrofitting strategies: (1) externally bonded CFRP plates and (2) internally embedded CFRP reinforcement within the beam’s cross-section. The computational investigation quantifies the influence of reinforcement placement on critical performance metrics, including ultimate load capacity, deformation ductility, and failure mechanisms. Numerical results demonstrate that internally integrated CFRP reinforcement significantly enhances structural ductility and peak load resistance, while maintaining a marginal mass differential. These findings underscore the critical role of reinforcement topology in optimizing stress redistribution and crack mitigation, offering actionable insights for the design of next-generation retrofitting protocols that prioritize both strength and serviceability. The study advances the discourse on sustainable infrastructure rehabilitation by delineating a pathway for leveraging embedded composite systems to transcend the inherent limitations of conventional concrete matrices.

• Periodical: Construction Technologies and Architecture (Volume 21)
• Pages: 85-95
• DOI: https://doi.org/10.4028/p-q8miLe
• Online since: January 2026
• Authors: Yahya Riyad, Taoufik Hachimi, Hatim El Assad, Hamza Bagar*, Fouad Ait Hmazi, Mouad El Khoudri, Ibrahim Mrani
• Keywords: Abaqus, Beam, CFRP, Concrete, Concrete Behavior, Reinforcement

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