Analysis To The Limit Range Of Side Shift Ratio For Transfer Story Structure

Although the practical application of transfer story structure in tall buildings is widely used in recent years, the study on its performance, however, is far beyond perfect. One of the most important fields is the description method of side-direction stiffness ratio in upper and lower part as well as the research to a sound stiffness ratio. In our country, sheering stiffness ratio y is commonly adopted by structure designers to control the variance of upper and lower rigidities in transfer structure floor, but there is inherent deficiency in this scenario because the arrangement of vertical components and the effect of flexural stiffiness among anti-side bending stiffness are omitted. As a consequence, it does not fit for the calculation of the beam type of support pillar transfer structure floor and the girder type of transfer structure floor. In this paper, by introducing side shifter angle ratio γ' in upper and lower part attached to transfer floor structure to describe the variance between the upper and lower stiffness, and considering the impact of sheering and flexural stiffness on side shifter along with the arrangement of vertical components, the deficiency that only the sheering stiffness is considered in sheering stiffness ratio y while flexural stiffness is omitted has been overcome. Hereby, the variance of upper and lower stiffness can be described more precisely.In the present paper, for three different transfer floor structure in tall buildings, by establishing calculation models and analyzing the sudden mutation of upper and lower stiffness and sheering force near transfer beams, the limit range of side shifter ratio has been proposed under anti-seismic conditions to of the supporting wall type of transfer story structure with huge base plate and big space, the beam supporting pillar type of transfer structure floor in tall building frame structure and the beam supporting pillar type of transfer story structure in the frame corewall structure. This work can provide references and help to solve practical designing problems.