Abstract
The effectiveness of a new retrofitting technique to upgrade the structural behaviour of reinforced concrete (RC) deep beams without steel stirrups using carbon fibre-reinforced polymer (CFRP) ropes as the only transverse shear reinforcement is experimentally investigated. Five shear-critical beams with rectangular and T-shaped cross-section are tested under monotonic loading. The strengthening schemes include (a) one vertical and one diagonal single-link CFRP rope that are internally applied through the web of the rectangular beam using an embedded through-section (ETS) system and (b) two vertical U-shaped double-link ropes that are applied around the perimeter of the web of the flanged beam using a near-surface-mounted (NSM) system. In both cases, the free lengths of the CFRP ropes have been properly anchored using epoxy bonded lap splices of the rope as NSM at (a) the top and the bottom of the web of the rectangular beam and (b) the top of the slab of the T-beam. Promising results have been derived, since the proposed strengthening technique enhanced the strength and altered the brittle shear failure to a ductile flexural one. The experimental results of this study were also used to check the validity of an analytical approach to predict the strength of shear strengthened deep beams using FRP ropes as transverse link reinforcement.
Highlights
IntroductionRetrofitting of shear-critical reinforced concrete (RC) beams using externally bonded (EB)
Retrofitting of shear-critical reinforced concrete (RC) beams using externally bonded (EB)fibre-reinforced polymer (FRP) sheets and laminates is a promising and extensively studied technique
This paper presents the findings of an experimental study aiming at the investigation of the efficiency of a new shear strengthening method to upgrade the performance of RC deep beams with rectangular and T-shaped cross-section using carbon fibre-reinforced polymer (CFRP) ropes (SikaWrap FX-50C) (Sika Hellas ABEE, Kryoneri, Greece) as the only transverse shear link reinforcement
Summary
Retrofitting of shear-critical reinforced concrete (RC) beams using externally bonded (EB). In order to avoid premature debonding failures at low strains, a promising technique known as near-surface-mounted (NSM) was developed [6] In this technique, FRP plates [7] or rods [8] are applied into pre-drilled vertical or shear-favourably inclined grooves on the concrete cover at the perimeter of the beam using epoxy adhesive. An alternative strengthening technique has been proposed in the literature for shear upgrading of RC beams using embedded through-section (ETS) reinforcement According to this retrofitting system, steel or FRP bars are inserted inside vertical or with shear-favourably inclination pre-drilled holes through the web of the beam, and are bonded to the surrounding concrete using an epoxy adhesive [12,13]. The presented analysis is used to predict the shear strength and the expected failure mode of the examined beams
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
