Nonlinear Analysis of Eccentrically Loaded Concrete filled Circular Steel Tubular columns

摘要

Based on the appropriate numerical constitutive model of concrete filled steel tubes, layered method was applied and fiber model method based on partial sinusoidal shape for concrete filled circular steel tubular (CFST) columns under both concentric and eccentric loading was proposed. Utilizing the relationship between the curvature of the worst section and sinusoidal amplitude, a FORTRAN program was developed and the behavior of CFST columns under concentric loading, eccentric loading of equal end-moment and unequal end-moment were analyzed, showing that the analysis results are in good agreement with the experiment results from references and the fiber model method can reflect the load capacity and deformation of the columns reasonably. Thus the reliability of the present method was validated and this work is the basic for the further researches on the practical expressions of load bearing capacity for the CFST columns under both compression and bending.