Analytical study on the behavior of CFRP-concrete bonded joint with a non-rigid end-anchor

Abstract

End-anchors have been widely used to prevent/postpone debonding failures in FRP-strengthened RC structures. The bond behavior between FRP and concrete with end-anchors can be investigated through FRP-concrete bonded joint with such anchors. Existing studies have found that deformation of FRP and the anchor, as well as slip of FRP-concrete interface at the anchored end can happen when the FRP is under external loading; therefore, the simple assumption that end-anchors provide a rigid end to FRP may result in significant overestimations of the bonding stiffness and strength. Against this background, this paper presents an analytical study on the closed-form solution to the full-range bond behavior of CFRP-concrete bonded joint with a non-rigid anchor. The obtained analytical solution was first verified through finite element analyses and test results, and then was adopted in a comprehensive parametric study to investigate the effect of mechanical properties of end-anchors on the overall bond behavior of the joint. This paper provides a better understanding of the bond behavior between FRP and concrete with a non-rigid anchor and shows that the design of such end-anchors should be based on CFRP-concrete interfacial characteristics for a desired bond behavior.