Strength of circular concrete columns confined by fibre reinforced polymer composites

It is well known that the compressive strength of reinforced concrete (RC) columns can be substantially enhanced by lateral confinement. This fact has enabled the retrofitting of existing RC columns through the provision of external confinement. Steel jacketing has traditionally been used for achieving such confinement, but fibre reinforced polymer (FRP) composites have rapidly become widely used instead in recent years. Consequently, a large number of studies have examined the axial compressive strength of FRP-confined concrete columns and several strength models have been proposed. This paper presents a performance assessment of nine existing axial compressive strength models for FRP-confined circular concrete columns using available test data. A new simple and accurate model is also proposed