Analysis of debonding failure modes in FRP-strengthened reinforced concrete beams using genetic algorithms

Abstract

The use of fibre reinforced polymer (FRP) composite materials for flexural strengthening of reinforced concrete (RC) structures is increasingly becoming a robust alternative to traditional techniques. Numerous numerical models have been proposed for estimating the increase of the flexural capacity, assessing the transmission of forces through the interface between the concrete and the FRP and describing the possible failure modes that can happen. Several of these models have been simplified in order to make them formulated into guidelines. Although they have not reached standard status yet, they are useful recommendations to be followed for repairing or retrofitting RC structures. This paper describes the main features of the following guidelines: the European “fib Bulletin 14”, the British Technical Report 55 and North American ACI 440.2R. Differences between them are discussed and a practical comparison is illustrated through a flexural strengthening problem that is solved through a structural optimization application based on Genetic Algorithms.