Anchorage of composite laminates in RC flexural beams

Francesco Micelli, University of Salento-Lecce, Italy 
Andrea Rizzo, University of Salento-Lecce, Italy 
Donatella Galati, University of Salento-Lecce, Italy 

This paper focuses primarily on flexural strengthening with pre-cured fibre-reinforced polymer laminates applied on reinforced-concrete beams with different anchoring devices, both chemically and mechanically applied. The results showed that the ultimate load of the strengthened beams was 35-80% higher than the control beam, depending on the type of strengthening system applied. The lower value corresponds to the beam strengthened using carbon-fibre-reinforced polymer without anchor spikes, the use of which increased the ultimate load by about 14%. The best performance of the strengthening was obtained for the beams strengthened with the hybrid laminates: steel anchors reduced the load drop after the peak, while in the case of the hybrid system and mechanically fastened carbon-fibre-reinforced polymer, the use of the mechanically fastened system resulted in a pseudo-ductile mode of failure. The experimental results were compared with analytical results obtained from the application of recently developed guidelines, published by the Italian Research Council (CNR).