Behaviour of Reinforced Concrete Beams Strengthened by CFRP Wraps with and without End Anchorages

Abstract

Use of Carbon Fibre Reinforced Polymer (CFRP) strips as externally bonded reinforcement, is a technically sound and practically efficient method of strengthening and upgrading reinforced concrete (RC) members. Externally bonded CFRP strips help in improving the structure performance by reducing deflections and/or cracking and increasing ultimate strength. The ultimate capacity of the strengthened beam is controlled by either compression crushing of concrete, rupture of CFRP and flexural shear cracking induced de-bonding atconcrete-CFRP interface. Present study deals with the use of externally bonded CFRP wraps instead of strips to strengthen RC beams in flexure with and without end anchorages. Six beams strengthened with CFRP wraps at bottom with and without anchorages, were tested with different a/d ratios. It was observed that use of CFRP wraps resulted in significantly increasing the stiffness and ductility of the RC beams along with increasing load carrying capacities of the strengthened RC beams with end anchorages.

Experimental investigation on the effect of geopolymer adhesive on the bond behavior between CFRP and concretes

“…In recent years, with the advantages of high‐mechanical performances, lightweight, corrosion resistance, and convenient construction, CFRP has been widely applied as a means of repairing damaged structures in in‐service practical strengthening engineering. [ 1–5 ] The conventional technique of CFRP strengthening of RC structure is formed by bonding CFRP and concrete members through epoxy adhesive, which can increase the bearing capacity and prolong service life of damaged concrete members, then resource wastes and economic losses caused by new projects can be avoided. In addition, quite a few forms of strengthening methods and numerical models of corroded concrete [ 6,7 ] and corroded reinforcement bars [ 8 ] are being studied to enhance the overall structural stability.…”

Flexural behavior of CFRP-strengthened reinforced concrete beams rubberized with finely minced rubber tire

“…By applying a second layer of (FRP) composite material to reinforced concrete beams, they can be significantly strengthened; samples of strengthened beams show an increase in strength capacity of (114%) [20]. Soffit-mounted, sideextending (CFRP)-wrapped reinforced concrete beams, together including and not including end anchors, improved the structural performance of the beams' ductility, load-carrying ability, and stiffness [21]. All repaired beams usually regain close to (80%) of their original bearing capacity when reinforced with (CFRP) sheets.…”

Design Provisions for End-Anchoring Devices in Concrete and Masonry Elements Externally Bonded With FRP Materials

“…Also, in (Khan and Fareed, 2014, [18]) the effect of U-shaped fiber sheets to strengthen RC beams in bending was studied. The beams were characterized by different value of the spanto-depth ratio (a/d) and the end anchorages was wrapped all along the cross-section of the beam.…”