Axial compressive behaviour of circular hollow section (CHS) strengthened by prefabricated FRP jacket system

This paper reports a series of tests on axial compressive strength and behaviour of steel circular hollow sections (CHS) strengthened by a prefabricated FRP jacket system, Sitejacket. The experiment program aimed to investigate the structural behaviour of FRP-jacketed CHSs including (i) axial compressive strength enhancement, (ii) axial behaviour of stub CHS and (iii) various failure modes. The main test parameter is the thickness of the CHS which is expected to directly influence the axial strength, failure mode and deformability. All test specimens were loaded to failure with a constant loading rate to enable close monitoring and recording of the failure process. Based on test results, strength and stiffness changes and different failure modes of the strengthened CHSs are reported. Full axial behaviour of various specimens including pre-and post-yielding stages of the jacketed CHSs was also presented.