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In this paper, the mechanical performance of concrete beams strengthened by an impregnated Carbon Fabric Reinforced Cementitious Matrix (CFRCM) composite is investigated.The study is aimed at the rehabilitation of the Finale Emilia hospital roofs, severely damaged by the 2012 Northern Italy earthquake. A 8-m-long concrete beam could be taken from the building for reinforcement and testing in a beam test setup. The composite is designed to be externally applied to the existing thin clay tile layer bonded to the concrete beam intrados.Two lamination cycles are considered, which differ in the way the partially-organic adhesion promoter is applied to the fabric. It is found that impregnation thorough fabric immersion provides a 1.5-fold increase in the ultimate strength of the strengthened beam compared to expedited impregnation with a brush. Besides, clay tiles make a very good supporting substrate, to the extent that cohesive fracture at the tile/concrete interface takes place on the verge of concrete failure near the hinge zone. Conversely, expedited impregnation of the carbon fabric with the adhesion promoter is unable to provide adequate fabric/matrix adhesion and leads to delamination failure. Estimates of the adhesion strength, of the optimal bonded length and of the composite as well as of the concrete strain at failure are also provided.

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