Axial compressive behaviour of special-shaped steel-fibre-reinforced concrete columns Available to Purchase

Special-shaped columns are extensively used in residential and official buildings as they increase the efficiency of indoor space. However, many studies on normal special-shaped concrete columns have demonstrated their poor ductility and requirement for additional reinforcement. To overcome these shortcomings, a novel cross-shaped column was designed to enhance the ductile deformation. This column integrates high-performance concrete (HPC) with high-strength stirrups (HSS). Ten cross-shaped column specimens were tested under axial compressive loading. The parameters investigated were the spacing of the stirrups, the strength of the HPC and the content of steel fibre. The test results showed that the HSS improved the axial compressive bearing capacity and ductility, and a close tie spacing improved the confinement, resulting in a significant enhancement of post-peak ductility with a moderate increase in column axial bearing capacity. Increasing the strength of the HPC did not effectively enhance the ductility for a large tie spacing. The use of steel fibre was found to enhance the bearing capacity and ductility, and a higher steel fibre content did not significantly delay the decrease in bearing capacity. The analytical results of existing high-strength concrete and fibre-reinforced concrete confinement models were compared with the test data and several parameters were assessed. The results indicate the need to develop confinement models specific to special-shaped columns.