Finite element analysis of beams bonded with end-anchored FRP straps

A concrete beam can be strengthened with fiber-reinforced polymer (FRP) straps attached to the tension surface. Stress concentration within the strap-end region may induce premature debonding failure, and this is one of the main disadvantages hindering this application. Experimental studies indicate that external end-anchor systems can delay or prevent end debonding. However, this technique needs to be thoroughly investigated prior to safe and widespread application. Firstly, this paper introduces a conceptual external end-anchor system. Then, a finite element (FE) analysis is done for a concrete beam strengthened with this system. Finally, results from the FE model and an analytical model are compared, and good agreement between them is observed. Both the numerical and analytical results indicate that an external end-anchor helps to mitigate stress concentration within the strapend region.