Continuum Technique For The Vibration Of Twin-Tower Connected Structures And Static, Dynamic Study On The Connecting Body

The twin-tower connected structure which widely developed in recent years is a new structure system. It is composed of two towers and an overhead body joining the two towers together. Many scholars in home and abroad have done a lot of experimental and theory researches on this structure, but most of them used the discrete method, and they did little study on the connecting body. Based on the existing research findings, this paper presents a continuum technique to analyze the system and the static & dynamic characteristic of the connecting body.Firstly, the structure forms of the connecting body which are commonly used in projects were generalized, and the structure properties under loads action and its applicable conditions of each form were analyzed. The conclusion is that the vierendeel truss is a more rational connecting body. At the same time, some jointed modes between the tower and the connecting body were also covered.Secondly, a piecewise continuous series-parallel connection model is taken as the computational model for the enlarged-base-multi-tower-connected structure. Then, the balance differential equations, which the unknown function is vertical displacement, were derived. And the boundary conditions and continuous conditions of some substructures compose the boundary value problems of partial differential equations.The responsed equations of beam's dynamic displacement which excitated by the supports plane motions of the fixed Timoshenko beam were derived. Then the dynamic internal forces of beam ends were gained from these equations. The dynamic internal forces, which substitute the static forces, were retroacted to substructures. The vibration balance differential equations of any substructure which include the vibration of the connecting bodies were obtained. These equations superpose corrected items on the primary equations. The physical and geometry constants and the vibration characteristics of the connecting body and the motion information of supports etc. were contained in these corrected items.Both modes of the symmetry twin-tower connected structures when the connecting body located in different locations and the asymmetry twin-tower connected structures, and the response of the connecting body on which vertical earthquake acts were analyzed by using the response spectrum method. The twist and coupled modes of the asymmetry twin-tower connected structures were more complicated than the symmetry ones. The taller position of the connecting body, and the more asymmetry of the two towers, the greater response of the connecting body on the vertical earthquake. The greatest dynamic-static-ratio appears in the span center, the values were between 0.25 and 0.3 approximately.Thirdly, an example of twin-tower connected structures was introduced, and theselection of the structure form, the choice of the structure members, the process of the static and dynamic computation were presented.Finally, some conclusions are summarized and the topics for further research are put forward to.