| The shear bond problems at the interface of Concrete-Filled Steel Tube(CFST) is one which are further concerned by more and more construction engineers and managers. The study on the shear bond behaviors at the interface of CFST is significant on the theory, based on the former research achievements, systematic experimental study and theoretical analysis on the shear bond behaviors have been carried out in this thesis. The main research works were concluded as follows:34 push-out tests of CFST are completed in this paper, including 22 circular and 12 square CFST specimens. Based on the results of experiment, composing of shear bond force, characteristic and rule of shear bond failure are discussed. The factors of effect on the shear bond strength are analyzed and the uniform relationship between bond strength with bond-slip on circular and square CFST is obtained. In addition, The strain of 2 circular and 2 square CFST specimens is tested sequentially. According to the test, the distribution of steel tube strain in course of shear bond failure is analyzed in detail.The finite element analysis model of the shear bond at the interface of CFST was also built up. Steel tubes, concrete and the interface between steel and concrete were modeled by Shell, 3D Entity and Contact element, respectively. Analog calculation is carried out by use of the ANSYS software environments. Afterwards, the calculating results of finite element method compare with the experimental results is proved to be consistent. It is also proved that finite element analysis model can simulate work state of shear bond failure nicety. An analysis is developed for the ratio of axial force to compressive strength that influences on shear bond strength, and the formula for bond strength and the ratio of axial force to compressive strength has been established.
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