At present, in the design of high-rise steel structure building structure, mostly USES the three dimensional space finite element program calculation and analysis, in the first stage design, regardless of the steel members, or the concrete member, rate as an ideal elastic material, the structure of space analysis, appropriate to simplify the structure of mechanics deals with, make it can not only reflect the stress of the structure performance, It is also suitable for the mechanical model of the selected structural analysis software.
As the calculation model for high-rise steel structure building structure is very complex, in order to reduce the degree of freedom structure, generally introduced the rigid floor assumption in counting, makes each floor all components on the floor in the translational and rotational degree of freedom of the plane to be expressed in the reference point of translation and rotation, thus greatly reducing the degree of freedom structure, at this time, Floor itself is not involved in whole structural analysis for structures, along with the diversification of high-rise steel structure building system, for a transition layer, floor partially open hole and plane arrangement of long and narrow complicated high-rise steel structure building structure system, the influence of floor deformation can no longer be ignored, if continue to use floor stiffness infinite assumption at this time, it could cause larger calculation error, In addition, for super high-rise steel structure, horizontal reinforcement layer is generally used. Since the waist truss and cap truss are overstorey members, if the floor stiffness is assumed to be infinite, the actual internal forces of the upper and lower chord bars cannot be obtained. Therefore, it is important to analyze the basic method first in the high-rise steel structure.