Behaviour of GFRP tube reinforced concrete columns under axial compression

This paper reports the result of an experimental investigation on the behaviour of Glass Fibre Reinforced Polymer (GFRP) tube reinforced concrete columns under axial compression. The GFRP tube was placed into the concrete to provide reinforcement both in the longitudinal and transverse directions. In this study, a total of 8 columns with 150 mm diameter and 300 mm height were cast and tested under axial compression. The columns were divided into four groups and each group contains two identical columns. The first group had two columns of plain concrete, and the remaining three groups were reinforced with solid, axially perforated and diagonally perforated GFRP tubes, respectively. The test results showed that for columns reinforced with solid GFRP tube, both the load-carrying apacity and the ductility capacity improved significantly. However, for axially perforated FRP tube reinforced columns, the load-carrying capacity increased only slightly. For diagonally perforated GFRP tube reinforced columns, the ductility capacity improved notably, but the increase was less than the increase in the solid GFRP tube reinforced columns.