RESULTS OF STATIC LOAD TESTS ON INSTRUMENTED ANALYSIS OF INTERFACE STRESSES OF RC BEAMS STRENGTHENED WITH PRE-STRESSED HYBRID CFS-GFS

The application of fibre reinforced polymer (FRP) as tension reinforcement has been widely used in repair and strengthening of concrete structures. The hybrid FRP sheets, which consist of a combination of carbon fibre sheets (CFS) and glass fibre sheets (GFS), have non-linear behavior. In this paper, firstly, the FE analysis model of interfacial stresses of RC beams strengthened with hybrid CFS-GFS is created. Comparing the FE results, the shear stress of the beams strengthened with hybrid CFS-GFS is smaller than that of the beams strengthened with double layered CFS. These indicate that the interface of the beams reinforced with hybrid CFS-GFS is better than that with CFS. Secondly, FE method is employed to analyze the RC beams strengthened with pre-stressed hybrid CFS-GFS. The results show that the maximum interfacial stresses can be reduced significantly and the efficiency of the high strength fibre sheet is improved when the anchor fastnesses are employed at the strengthening ends.