Nonlinear Finite Element Analysis On Square High-strength Concrete-Filled Steel Tubular Short Columns Under Axial Loading

The high-strength concrete-filled steel tubular (HSCFST), in addition to the merit that the common concrete-filled steel tubular (CFST) has, can also economize concrete further and ease structure dead load, obtain enormous economic benefit and good social efficiency thus, therefore HSCFST received a more and more far-ranging application in the actual engineering. However, the search of square HSCFST short columns is over-emphasized to experimental investigations currently, therefore, there has the necessary to carry on a finite element analysis, as to carry on a further analysis on the mechanical properties of the square HSCFST short columns under axial loading.Based on ago study results, this paper had made use of the finite element analytical software (ABAQUS) to carry out the research on mechanical properties and simplify calculation methods and stress-strain curves for steel tube and core high-strength concrete of square HSCFST short column under axial loading. The main achievements can be summarized as follows:(1)Finite element model of square HSCFST short columns was obtained by ABAQUS, which is an common analysis software. The constitutive model of steel tube and core concrete of HSCFST is selected. The core concrete is modeled using concrete damaged plasticity model. The steel tube is modeled using plasticity modeled which is isotropic elasticity and plasticity model with a Von Mises yield surface. In the model, the effect of the bond between steel tube and concrete was considered.(2)Mechanical properties of square HSCFST short columns were analyzed based on the finite element analysis method. This paper gave an analysis on the destroy model of HSCFST and the stress-strain curves for steel tube and the core high-strength concrete of square HSCFST short columns.(3)Stress-strain curves for core concrete is investigated and analysis concrete strength and width to thickness ratio. Based on a wide scope parametric analysis, simplified calculation methods for stress-strain curves of core concrete of concrete-filled steel tube under axial compression is proposed, which may be referred for seismic design.