Dynamic Performance Analysis of Composite Frame with Concrete-filled Steel Tubular Columns Based on Nonlinear Beam-column Fiber Element

Abstract

The three-dimensional elements method is imperfect in computational efficiency to simulate the behavior of structural systems based on elastoplastic theory. A finite element model (FEM) using beam element was performed to simulate the composite frames with concrete filled steel tubular (CFST) columns, and the separate modulus approach and the uniform modulus approach were used to the beam elements, respectively. The results from the two methods are verified with the experimental results of the CFST members and the numerical curves, respectively. The two validated models were used to perform the model analysis and elastic dynamic time history analysis under three different frequent earthquake waves for a 13 story composite frame with CFST columns, respectively. The top story displacement and acceleration-time history responses, the relative story drifts and the maximum dynamic magnification coefficients of the frame were contrasted with different two models. The results shown that the separate and uniform modulus approach are similar generally for the dynamic characteristics of composite frame under frequent earthquake.