Research on the Effect of Stiffness Ratio Between Frame and Core Tube on Seismic Response of Super High-rise Building Under Frequent Earthquake

Abstract

The stiffness ratio of frame to core tube has an important influence on the seismic behavior of frame-core tube hybrid structure which is a high-rise building structure system widely used in the world. In this paper, nine models of concrete-filled steel tubular frame-concrete core tube super-high-rise hybrid structures with different stiffness ratios are established by using finite element method, and the effect of stiffness ratio on inter-story displacement angle, top displacement and base shear force of super high-rise buildings under frequent earthquakes is studied. The results show that, with the increase of stiffness ratio, the inter-story displacement angle, the top displacement and the base shear force change complicatedly, the maximum base shear force increase, and the maximum inter-story displacement angle and the maximum top displacement first increase then peak, and that the strengthening layer with outrigger obviously improves the deficiency of lateral stiffness caused by height. This study provides a reference for reasonable determination of stiffness ratio and optimization of structural seismic design.