Experimental study of concrete filled FRP tubes under axial loading

This paper discusses the strength behaviours of fibre reinforced polymer (FRP) confined concrete filled tube (CFT) columns, which have been increasingly used as an effective column structure. Firstly, the state-of-the-art development in the applications of FRP tube in structural engineering is presented, and then, part of preliminary experimental results from an ongoing research project on the structural behaviours of concrete filled FRP tubes at Central Queensland University are discussed in terms of height-to-thickness and height-to-diameter (slenderness) ratios. The compressive strength of the FRP CFT and failure modes were obtained by varying the slenderness ratios of CFTs. The results are analysed and discussed in terms of the effects of both slenderness ratio and lateral confinement due to the FRP tube on the stress state and therefore, on failure mode and strength behaviour.