Experimental behaviour of square high-performance concrete slender columns under biaxial eccentric loading

In this research, an experimental investigation of the behavior of square high-performance concrete (HPC) slender columns was carried out. A total of Eighty-One Square High-Performance Slender (SHPS) Columns subjected to axial, uniaxial and bi-axial loading were constructed and tested. The primary test parameters were the grade of HPC (varied from M60 to M80), steel ratios (2.01% to 4.52%), and eccentricity along the major axis was 28 mm. The test outcomes demonstrate that these parameters influence the strength and behavior of Square High-Performance Slender Columns. The steel ratio is a significant factor that influences the bearing capacity of column specimens, as in the experiment, and the load-bearing capacity of the specimens increased highly with increasing grade of concrete. Proper material constitutive models for SHPS columns are developed and validated against experimental data. A comparison of experimental failure loads to predicted failure loads using the method described in the reference showed good agreement. In the research work, interaction curves are plotted for high-performance slender columns with uniaxial and biaxial loading and novelty is observed that by comparing IS, ACI and present results, it was seen that IS code gives minimum load carrying capacity with heavier sections and high cost. Whereas ACI gives maximum load-carrying capacity with lighter sections and low cost. However, the present study gives an intermediate section with optimum load capacity and economy. Also, it is observed that columns tested in bi-axial compression are more sensitive than axial and uniaxial columns. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024.