Theoretical Research On Suspen-Dome

Suspen-dome is a new self-equilibrium space structure, composed of single-layer lattice shell and cable-strut tensile structure. For its novel and beautiful shape, it has a widely practical perspective. The study on suspen-dome was just started in recently several years and there were no comprehensively and deeply research achievements in our country. Some systemic and deep research work on the theory of suspen-dome is carried out in this thesis.Based on reading many literatures, developmental history and present situation of suspen-dome are described, and project applications are introduced in this thesis. According to the combination of suspen-dome, structural principle, characteristic and types of the structure are described. At last, the work content of this thesis is put forward.In this thesis, a new method named local analysis method was presented which the whole structure is divided into two parts: the upper structure and the lower structure. The problem distribution of initial pre-stress of suspen-dome can solved by this method. Combined the topological relation of suspen-dome and the concept of overall feasible pre-stress , by using the equilibrium matrix theory method and linear static method, the problem of distribution of initial pre-stress of suspen-dome is simplified. Program has been developed based on the local analysis method.The static behavior under vertical loads of Kiewitt's suspen-dome was analyzed on the initial state. Moreover, the behavior of suspen-dome and single-layer lattice shell are compared. The influence of kinds of parameters is studied.The stability behavior of Kiewitt's suspen-dome was analyzed on the initial state. By the geometrical nonlinear finite element method, the equilibrium path is traced using the cylindrical arc length technology and incremental Newton-Raphson method. The influence of kinds of parameters is studied.Two types of seismic calucation methods that are response spectrum analysis and time-history analysis are used to analyze the seismic response of Kiewitt's suspen-dome under lateral seismic action and vertical seismic action. The result obtained by above-mentioned methods and the code method are compared.Genetic algorithm method is proposed to optimize the prestress of suspen-dome. From the randomized initial population, using the operators such as select, crossover and mutation, it can converge the globe optimum solution. Two-level algorithm is developed to deal with the two objective function optimal designs that are the radial constraint force and the axial force of the upper structure. Corresponding program has been developed to optimize the prestress of the Lamella's suspen-dome and Kiewitt's suspen-dome.Analysis of construction process is the key problem to suspen-dome. A new method named inverse analysis of construction process is proposed to determinate the ideal status in each step of construction, including internal force and the coordinate of points. From the initial value that is the internal force and the geometrical coordinate of the initial state, according to the constructionsequence to remove the cable-strut tensile structure, it can determinate the zero state of the structure.At the end of the thesis some conclusions are summarized and the problems that should be studied further are put forward.