ABSTRACT
Abstract This paper presents the results of an experimental program that examines the behaviour of reinforced concrete beams strengthened using carbon fibre reinforced plastic (CFRP) sheets. The concept of equivalent strength is introduced for comparative purposes and its applicability to design is discussed. The results and analysis of three 2m reinforced concrete beams and two 5m reinforced concrete beams of various tensile reinforcement configurations are presented. Three different tension reinforcement configurations: full-strength, under-strength, representing a beam where tension reinforcement is lost or insufficient for the required strength; and rehabilitated-strength, representing a beam with the same steel reinforcement as the under-strength beam but rehabilitated through the external application of CFRP sheets to attain the same yield strength as the full-strength beam were tested. The beams were tested under monotonic loading. The load versus centre span displacement, as well as moment - curvature graphs were produced for each of the specimens tested. The CFRP sheets are shown to enhance the stiffness of the beams, the load at which the tensile steel yields, the stiffness of the beams after yielding of the tensile steel and the maximum load of the beam. An equivalent capacity based on the load at which the tensile steel yields is proposed to ensure adequate stiffness within the working stress range.
