CHARACTERISTICS OF BEARING CAPACITY OF SQUARE CFST COLUMNS WITH BINDING BARS UNDER ECCENTRIC LOADS

摘要

Finite strip method (FSM) was adopted to calculate the bearing capacity of square concrete filled steel tube (CFST) short column with binding bars and the constitutive relationship of square CFST with binding bars was employed in the numerical analysis, numerical results are in good agreement with the experimental results. Then parameter analysis of the square CFST short columns with binding bars under eccentric loads were conducted and results show that the ultimate capacity of the short columns under eccentric loads are improved with the decrease of space distance and the increase of diameter of binding bars; by increasing the thickness of steel tubes, the N/Nu-M/Mu curves become pinching, and the N/Nu-M/Mu curves become protruding with the enhance of concrete strength; the maximum and minimum ultimate capacities of short columns subjected to biaxial eccentric loading can be obtained at the maximum and minimum principal axis of inertia, respectively; similar effects of parameters on N/NuM/Mu curves of the short columns under eccentric loads are found.