Theoretical And Experimental Research Of Cable Dome With Outer Truss Ring

Composed of both cable in tension and struts in compression, Cable dome structures which was first proposed by Geiger is known as the most successful application of tensegrity system conceived by Fuller. The most notable feature of the cable dome is high structural efficiency. On the basis of being prestressed to provide structural stiffness, this type of structures, featuring in light weight, giant span and verified structural styles, etc. has been regarded as representing the high level of giant-span spacial structures. The major two types of cable-dome structures being widely researched and practiced in real projects throughout the world are Geiger and Levy. The cable dome with outer truss ring analyzed in this article is a special type of cable domes, which has only been practiced in one projects in U.S.A. and has been recorded in a article. Proposing many types of composition forms of cable dome with outer truss ring, this article commits itself to systematically researching and analyzing the Geiger dome with outer truss ring through both theory and practice on such areas as the distributions of initial prepress, the characteristics of both static and dynamic forces, the analyses in earthquake response. At last, this article testifies all the theories raised and conclusions drawn by experimenting on specific models designed and processed on this purpose.Based on the relevant references both in China and abroad, Chapter 1 reviews cable dome structures in its developing history, the practical appliances in engineering constructions, the existing conditions of both domestic and foreign researches in this area. Combined with the characteristics of cable dome with outer truss ring, the research contents of this paper are determined.Chapter 2 analyzes the features of geometric component in cable dome with outer truss ring. 6 types of cable dome with outer truss ring, many composition forms of different arrangement of web members and different truss gradient were proposed.In Chapter 3, a quick and simplified calculation method for initial prestress distribution of Geiger dome with outer truss ring was proposed. And the general equations corresponding to domes with an inner hoop and domes without an inner hoop were derived respectively. Using these equations, the initial prestress distribution of domes with certain parameters was obtained and compared with the results obtained by FEM. The results demonstrate that these equations, being precise and practical, could be effectively applied on practical constructions and could function as a useful complement in theoretical analysis.The analytical researches of structure functions with static force as the basis for further researches of Geiger dome with outer truss ring. Chapter 4 analyzes the force-bearing and position-changes of both cables and struts under either full-span load or half-span load. The impacts on the performance of force-bearing being subject to the changes of prepress, the changes of height and gradient of truss, have also been studied hereby.Chapter 5 analytically researches the Geiger dome with outer truss ring, concerning their respective self-vibration frequency and characteristic distributions of vibration types. It also calculates and analyzes the impacts on the potency of dynamic forces exerted by the prepress-levels, the height and gradient of truss, the sizes of the sections of hoop cables.Chapter 6 focuses on the performances of Geiger dome with outer truss ring in terms of earthquake response, which includes analyses in both internal forces of the components and the time-history patterns of position-changes.In Chapter 7, the real model of the Geiger dome with outer truss ring (diameter=5.0 meter) was designed and produced on the basis this article's theories. Experiments on prestress tensioning of Geiger dome with outer truss ring, static behavior of structure under full-span and half-span load are carried out. The results between the experimental data and theoretical analysis of the structure are compared and analyzed.At last, all the research results are summarized. Some problems that will be solved in the future are listed..