Concrete damaged analysis in strengthened corbel by external bonded carbon fibre fabrics

Abstract

This paper describes an experimental and theoretical analysis of strengthened damaged reinforced concrete corbel by gluing carbon fibre fabrics. The main objective of this study is to investigate the damage effect on the strengthening of reinforced concrete structures, especially on short reinforced concrete corbel and to propose an analytical model. Therefore, an experimental program was developed to evaluate the mechanical damaging effect on short corbels behaviour by using strain gauges. According to this program, five reinforced concrete corbels were tested under a three-point bending up to failure. Three of them were damaged at 45, 65 and 90?% of their ultimate load. After the specimens were repaired with carbon fibre fabrics and the loading was conducted till their failure. The fourth corbel which was not damaged. It was strengthened and tested until its collapse. The last one is the reference specimen corbel which was not reinforced. The test results with corbel specimens which were strengthened and unstrengthened are given. The significance to member performance is also explained. The measured load versus strain was too measured in the same way (with precision strain gauges) for others materials such as composite fibre fabrics, steel bar and concrete at the cross section of corbel. The study shows that the composite fibre fabrics using bonding technique could be a convenient and effective strengthening method for concrete structures. Thus, steel reinforcement and carbon fabrics played a major role in the repair of corbels. A theoretical analysis is presented describing the behaviour of strengthened damaged concrete corbel using the damage theory of reinforced concrete beams.