Seismic Behavior Of Diagrid Core-tube Structures In High-rise Buildings

At present,because of the high efficiency of the transmission structure and the unique advantages of architectural aesthetics,the oblique grid structure is increasingly favored by architects.This new type of structure is gradually adopted by high-rise buildings.Compared with the theoretical results of traditional structures,the current stage is still in its infancy,and the relevant theoretical formula derivation and premise assumptions are not mature enough.Traditional frame shear wall structure and oblique grid structure have great differences in the mechanical characteristics of structural members under earthquake action.Therefore,it is necessary to deeply study the seismic performance of this new structural system under the multiple and rare earthquakes.In order to compare the difference between the seismic behavior and the mechanical characteristics of the two structural forms under the same seismic force,the main arrangement of the paper is as follows:1,Establishing a diagonal grid structure and frame structure under a two-dimensional planar element.Comparative analysis of the lateral stiffness of the two structures,the force characteristics of the members and the shear lag effect.Initially grasp the characteristics and laws of the structural members under the same vertical and horizontal loads of two structural forms,The characteristics of large stiffness and small shear lag effect of skew grid structure are pointed out.At the same time,the calculation model needed in Chapter 3 is established and the rationality of the structure is analyzed.2,Based on the example of Guangzhou West Tower Project,a three-dimensional oblique grid structure and frame shear wall structure model are established according to the same principle of body shape and material dosage.Elastic seismic response spectrum analysis.From the lateral stiffness of the overall structure,the shear force of the inner and outer cylinders,the proportion of the overturning moment,the axial distribution of the structural flange and the web column,etc.It is pointed out that the exterior oblique column of skew grid structure has higher importance,larger overall stiffness and smaller shear lag effect.3,Static nonlinear analysis of the above two structural models.In the rare earthquake,the lateral stiffness of the structure,the shearing force of the inner and outer cylinders,the distribution characteristics of the overturning moment,the structural failure mode,and the number and degree of plastic hinge development are compared.Points out the shortcomings of oblique grid structure in ductility...