Analysis of the effectiveness of reinforcing bent reinforced concrete elements by extending the compressed zone: review of experience and prospects for application to beams with basalt-plastic reinforcement
DOI:
https://doi.org/10.26906/znp.2026.66.4626Keywords:
basalt-fibre-reinforced plastic reinforcement, reinforcement of reinforced concrete structures, section enlargement, concrete overlay, compression zone, stress-strain stateAbstract
The global problem of reinforced concrete structure degradation caused by steel reinforcement corrosion has accelerated the transition of the construction industry toward non-metallic composite reinforcement, particularly basalt fiber-reinforced polymer (BFRP) bars. BFRP reinforcement offers significant advantages, including high tensile strength, complete corrosion resistance, and environmental sustainability. However, the absence of a yielding plateau and the relatively low modulus of elasticity of BFRP reinforcement require specific design approaches. To prevent sudden rupture and brittle structural failure, international standards recommend designing such beams as over-reinforced members, which ensures a safer failure mode through concrete crushing in the compression zone but results in increased serviceability deflections and limited utilization of the tensile strength potential of composite reinforcement. This study aims to summarize international experience in strengthening flexural reinforced concrete elements by increasing cross-sectional dimensions and to theoretically substantiate the feasibility of applying concrete overlays to BFRP-reinforced structures. A systematic analysis of previous studies demonstrated that increasing the compressed zone height improves structural stiffness, shifts the neutral axis upward, and increases load-bearing capacity by approximately 60–88%, while showing considerable potential for improving the performance of BFRP-reinforced beams.
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Copyright (c) 2026 Olexander Valovoi, Alexander Eremenko, Maksym Valovoi, Viktor Malashenko
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