Axially Loaded High-Performance Concrete Columns With Steel Fibers

High-performance concrete (HPC) has been studied extensively at many research centres, because of its increasing use in reinforced concrete buildings. Since HPC is a brittle material, studies have been done to increase its ductility. Increases in longitudinal and/or transverse steel ratios can improve the ductility of HPC elements. The addition of fibres also increases the deformability and thus the ductility. Hence the transverse steel ratio can be reduced by using fibres. This paper presents a study of axially loaded columns made with high-performance concrete containing steel fibres. The average compressive strength of the concrete was 80 MPa. The volumetric ratios of fibres were: 0.25%, 0.50% and 1.00%, and the stirrup ratios were 0.55% and 0.82%. The longitudinal steel ratio was the same for all columns tests, the W/C was 0.37, 10% silica fume was added and it was also necessary to use about 3% superplasticizer to improve workability. A comparison was made between the results for columns in high-strength concrete with and without fibres. It was observed that only the cross-sectional core effectively contributed to the load capacity of the columns.