Strengthening RC Beams Using Stainless Steel Continuous Reinforcement Embedded at Ends
Publication: Journal of Structural Engineering
Volume 146, Issue 5
Abstract
An innovative system for the flexural strengthening of RC structures designated continuous reinforcement embedded at ends (CREatE) is presented in this research work. The main characteristics and procedures for the application of this new strengthening technique were described. To evaluate the performance and efficiency of this technique, a set of RC T-beams was subjected to a four-point bending test setup. The reference RC T-beam was not strengthened; all other RC T-beams were strengthened with postinstalled stainless steel bars. Different application arrangements and different amounts of reinforcement were considered, and the CREatE technique was tested under monotonic and cyclic loading histories. The tests were modeled using the nonlinear finite-element method (FEM) to predict the performance of the RC T-beams, which allowed analyzing, in detail and with good agreement with the experiments, the influence of the CREatE technique on the (1) strains developed in the concrete, (2) cracking patterns, and (3) strains developed in the stirrups. Apart from the expected increases in the flexural stiffness and load-bearing capacity of the T-beams, the results showed that the use of the CREatE technique led to higher ductility indexes in the displacement compared with traditional techniques. Moreover, with the CREatE technique, premature debonding of the reinforcement material from the concrete tensioned surface—commonly observed in externally bonded reinforcement (EBR) strengthening systems—was eliminated.
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Data Availability Statement
Some or all data, models, and code generated or used during the study are available from the corresponding author by request, such as developed numerical models.
Acknowledgments
The first and third authors are grateful to UNIDEMI for the scientific research grants under the Strategic Project PEst-OE/EME/UI0667/2014. The third author also expresses gratitude to Fundação para a Ciência e Tecnologia for a post-doctoral grant SFRH/BPD/111787/2015. The authors thank Hilti Portugal for providing the drilling equipment and mechanical anchors, and S&P Clever Reinforcement Ibérica for providing the epoxy resin used in this research work.
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Published In
Journal of Structural Engineering
Volume 146 • Issue 5 • May 2020
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©2020 American Society of Civil Engineers.
History
Received: May 12, 2018
Accepted: Oct 14, 2019
Published online: Feb 29, 2020
Published in print: May 1, 2020
Discussion open until: Jul 29, 2020
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