Semi-analytical Analysis Of Super Tall Building Bundled Tube Structures Due To Deterministic Dynamic Loadings

The super tall building bundle-tube structure is one of widely used new structure formers in this century. In the thesis, the problems of the bundle-tube structure due to deterministic dynamic loadings have been analyzed by semi-analytical method based on Ordinary Differential Equation solver (ODEs). It employs three-dimensional continuous distribution mass model of the foundation and superstructure. The subgrade of the super tall building bundle-tube structure is idealized as the semi-infinite elastic body, the superstructure and foundation are simplified equivalently and continuously into a combination of stiffened-thin-wall tubes on the semi-infinite elastic subgrade. Then a semi discretization is made by some longitudinal nodal lines, the unknown deformation functions defined on the lines are used as primary unknowns, and interpolating functions are implemented between the lines. Thusly, the displacement field or motion field of the stiffened-thin-wall tubes could be expressed by the generalized coordinates. The problems of structural dynamics are thusly inverted to the boundary value problems of ordinary differential equations in terms of Hamilton principle. By ODEs named COLSYS(coded computer program), numerical solution of the equations will be obtained. Some reasonable conclusions have been obtained from the computing results of examples, which hope providing very effective references to the conceptual aseismic design of the super tall building bundle-tube structure. The main creative works can be listed as follows:(1) The signification that the super tall building bundle-tube structure is a new and promising structure system suiting to the need of society development was discussed so as to show the meanings to analyze the type of the structure with three-dimensional continuous distribution mass and stiffness model by the semi-analytical method based on ODE Solver both in theory and in practice.(2) Discussing basic dynamic problems of the super tall building bundle-tube structure, for example, how to treat the subgrade; how to establish the three-dimensional continuous distribution mass and stiffness model of the foundation and superstructure; how to select generalized coordinates to describe the dynamic behavior of the structural system due to dynamic loadings. (3) The steady-state response of the super tall building bundle-tube structure due to multi-dimensional harmonic deterministic loadings was analyzed by semi-analytical method. The resonant response has computed as well, which will help us further understand the entire dynamic performance of the structural system.(4) A new semi-analytical principle and method for analysis of the super tall building bundle-tube structure due to arbitrary deterministic dynamic loadings has been developed. Then multi-dimensional rectangle impact and explosion impact loadings have been analyzed by the semi-analytical method. Some reasonable and significant conclusions are obtained as well.By means of analyzing the results of computing examples, some reasonable and significant conclusions are obtained and these imply that the simplified semi-analytical model is reasonable and feasible, which provide an feasible analytical method for project design and initial design and earthquake-resistance conceptual design and the entire dynamic property evaluation of the super tall buildings adopting bundle-tube structure.