Experimental Behaviour of Square High-Performance Concrete Slender Columns Under Different Loadings

The present study conducted an experimental investigation on the behaviour of square high-performance concrete (HPC) slender columns. A total of 81 square high-performance slender (SHPS) columns were constructed and subjected to uniaxial and biaxial loading, with the aim of examining their performance. The key parameters investigated in the tests were the grade of HPC (ranging from M60 to M80), reinforcement ratios (ranging from 2.01 to 4.52%), and an eccentricity along the 20% from the major axis. The test results show that these parameters significantly influenced the strength and behaviour of square high-performance slender columns. Notably, the steel reinforcement was found to be a crucial factor affecting the bearing capacity of the column specimens, as demonstrated in the experiments. Furthermore, the load-carrying capacity of the specimens exhibited a substantial increase with higher grades of concrete. To accurately determine the material behaviour of square high-performance slender columns, constitutive models were developed and validated against the experimental data using the non-linear finite element software. Comparing the experimental failure loads with the predicted failure loads based on the FEM method yielded favourable agreement. From the experimental results, it was that as the load increased, the deflection decreased for both uniaxially and biaxially loaded columns, highlighting the novelty of this finding. Additionally, the columns subjected to biaxial loading displayed greater sensitivity compared to their uniaxial loading.