Abstract：In order to study the cooperating performance between steel tube and core concrete in the joints between large-section CFT giant columns and transferring girders or trusses in super high-rise buildings, a new detailing named distributive beam is suggested by authors. The cooperating behavior between core concrete and steel tube in CFT giant columns with distributive beam detailings in beam-column joints was numerically investigated based on the test results. For further numerical analysis of the tested specimens, a refined finite element (FE) model using ABAQUS is developed to compute the axial load-axial deformation relationship, failure mode of specimens and percentage of the load shared by the concrete. The analysis results agree well with the test ones, which validate the correctness of the FE model. Parametric analysis is conducted on beams with 47 kinds of sections and large-section CFT columns with 5 kinds of cross-sections. It can be concluded that the yield capacity of distributive beam is larger than the full cross-section shear strength of the beam, while the ultimate capacity is below the full cross-section tensile strength. Meanwhile, the mechanic behavior and load transfer mechanism of distributive beam is also analyzed. Finally, a finite element model of 14-storey large-section CFT column is established and to evaluate the cooperating performance of large-section CFT columns with distributive beams in a possible practical project. The analysis results indicate that the plane section assumption can be fulfilled by setting the distributive beam detailings.
