Static and dynamic response of damaged RC beams strengthened with NSM CFRP rods

Abstract Behaviour of RC beams damaged and strengthened with near surface mounted (NSM) carbon fibre reinforced polymer (CFRP) rods has been experimentally investigated. In this paper, results of static bending and dynamic tests are shown and discussed. Experimental program foresaw that RC beams were damaged by increasing loads to produce different degrees of cracking. The strengthened RC beams using NSM CFRP rods were then subjected to bending with the same loading path and, under increasing load, carried out to failure. The static behaviour of beams has been analysed comparing experimental results with those obtained by a nonlinear theoretical method. Changes in the properties of RC beams such as stiffness and ductility have been studied theoretically. Moreover dynamic response of damaged and strengthened beams has been experimentally investigated such as natural frequencies and vibration mode shapes. Finally, dynamic measures have been taken to validate the strengthening method.

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