Behavior of NSM FRP flexurally-strengthened RC beams with embedded FRP anchors

Flexural strengthening of RC beams by applying the near-surface mounted (NSM) fiber-reinforced polymer (FRP) into the bottom concrete cover of the beam has been proved to be efficient by abundant previous studies. However, it was found from these studies that NSM FRP-strengthened RC beams frequently failed by FRP premature debonding, which limited the strengthening efficiency of the NSM FRP. In order to fully exploit the strengthening efficiency of the NSM FRP, anchorage devices are normally needed to mitigate the debonding failure. However, existing studies on the anchorages for NSM FRP-strengthened beams are still limited. A novel embedded FRP anchor (EFA) is therefore proposed by the authors for the anchoring of NSM FRP. In the present paper, the concept, manufacture and installation process of the proposed EFA are first presented. Then, the effectiveness of the EFA in NSM FRP-strengthened beams is verified through a test program consisting of four full-scale RC beams. The test results showed that the EFA is able to mitigate NSM FRP end debonding and therefore improve the load-carrying and deformation capacities of NSM FRP-strengthened RC beams.