Title:
Developed Approach for Shear Modeling of Embedded Through-Section Fiber-Reinforced Polymer-Strengthened Reinforced Concrete Beams
Author(s):
Linh Van Hong Bui, Hidehiko Sekiya, and Boonchai Stitmannaithum
Publication:
Structural Journal
Volume:
122
Issue:
4
Appears on pages(s):
155-172
Keywords:
analytical model; embedded through-section (ETS); fiberreinforced polymer (FRP); flexural-shear deformation theory (FSDT); reinforced concrete beams; shear strengthening
DOI:
10.14359/51746674
Date:
7/1/2025
Abstract:
There is a need to model the complete responses of shear-critical
beams strengthened with embedded through-section (ETS) fiber reinforced polymer (FRP) bars. Here, a strategy is proposed to integrate two separate approaches, flexural-shear deformation theory (FSDT) for element fields and a bonding-based method for ETS strengthening, into a comprehensive computation algorithm through localized behavior at the main diagonal crack. The use of force- and stress-based solutions in the algorithm that couple fixed and updated shear crack angle conditions for analyzing the shear resistance of ETS bars is investigated. The primary benefit of the proposed approach compared to single FSDT or existing models is that member performance is estimated in both the pre-peak and post-peak loading regimes in terms of load, deflection, strain, and cracking characteristics. All equations in the developed model are transparent, based on mechanics, and supported by validated empirical expressions. The rationale and precision of the proposed model are comprehensively verified based on the results obtained for 46 data sets. Extensive investigation on the different bond-slip and concrete tension laws strengthens the insightfulness and effectiveness of the model.
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