• Proceeding of KASS Symposium
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• 2005.05a
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• pp.161-166
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• 2005

In spatial structures with large spaces, one important issue in structures with large spaces is how to carry the weight of the roof. A tensegrity cable dome structure is a kind of soft structural system using the tension cable and compression column as a main element. The tensegrity cable dome is built into a variety of shape around the world but then a collapse accident is increasing. Owing to a collapse accident we must grip of the collapse mechanism to prevent an accident and construct the structure with safety and economy. In this study, I investigated the unstable characteristics of the Geiger-type and Flower-type tcnsegrity cable dome structures, which is the lightweight hybrid structures using compression and tension elements continuously, according to the difference of loading conditions.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.04a
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• pp.93-100
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• 1998

The basic systems of spatial structures such as shells, membrane, cable-nets and tensegrity structure have been developed to create the large spaces without column. These structures may have large freedom in scale and form, and especially tensegrity structures are received much attention from the view points of their light weight and aesthetics. But There re some difficulties concerning structural stability, surface formation and construction method. One of the way to solve these problems reasonably is a combination of tensile members and rigid members. A structural system based on this concept is referred to as the "HTS ( Hybrid Tension Structure )". This is a type of flexible structural system which is unstable initially, because the cable material has little initial rigidity. As cable - dome hybrid structures is a type of HTS, the initial stress for the self- equilibrated system having stable state have to be introduced. To determine initial stress having stable state, the shape finding analysis is required before the stress - deformation analysis. In this paper, the primary objective is to derive the nonlinear finite element formula of cable and truss members considering geometric nonlinearity for shape finding of cable-dome, and to propose the method to decide the initial stress by the shape analysis of cable-dome hybrid structure with the self-equilibrated state.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.596-605
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• 2005

The cable dome, proposed by Geiger after developing Fuller's idea of tensegrity and improved by Levy, is a new type of large span space structures. In this paper, formulations of the initial forces distribution in members of two main systems of cable dome, which are Geiger dome and Levy dome, are presented. By analyzing the static performance of Levy dome and the variation of internal forces in members of the structure, four groups of design parameters in cable dome structure are represented in terms of: (1) the numbers of rings and the spaces between the rings; (2) the slopes of ridge cables; (3) the lengths of struts; (4) the initial force in one member of the structure.

• Journal of Korean Association for Spatial Structures
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• v.12 no.1
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• pp.69-75
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• 2012

The purpose of this paper is to study comparative analysis of cable dome structures by reinforcement effect with bracing and fabric. Tensegrity systems are stable structures which are reticulated spatial structures composed of compressive straight members, struts, and cables. Tensegrity structures need to be introduced to the initial stress for the self-equilibrated system to have a stable state. In this paper, the effect of reinforcement resisting the in-plan twisting is investigated for the Geiger-type and Zetlin-type models reinforced by bracing and fabric. The effect of initial imperfection is also studied because the structural instabilitity phenomenon of shell-like structures is very sensitive according to the initial condition. We study a more exact analysis concerning the structural instability of tensegrity structures using nonlinear analysis program. Then, two types of tensegrity models will be analysed and compared.

• Steel and Composite Structures
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• v.6 no.5
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• pp.417-433
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• 2006

In this paper, a non-linear structural analysis software with pro-processing and post-recessing function is proposed by the author. The software incorporating the functions of the structural analysis and geometrical design of Tensegrity structures. Using this software, Cable Dome is analyzed as a prototype, a comprehensive study on the structural behavior of Tensegrity domes is presented in detail. Design methods of Tensegrity domes were proposed. Based on the analysis, optimizing design was performed. Several new Tensegrity domes with different geometrical design scheme are proposed, the structural analysis of the new schemes is also conducted. The analysis result shows that the proposed new forms of the Tensegrity domes are reasonable for practical applications.

• Journal of Korean Society of Steel Construction
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• v.16 no.3 s.70
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• pp.345-353
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• 2004

One of the key issues in spatial structures with large spaces is how to carry the weight of the roof. This can be solved by the effective use of tension members. A cable dome structural system facilitates the construction of a large space structure. As external load increases, however, the cable dome structural system is put at risk due to global buckling. This study measures the shape of the Geiger and Flower-type cable dome by applying an initial stress. This unstable phenomenon is also examined using a perfectly shaped model and an imperfect model, which are both subjected to an axisymmetric load.

• Journal of Korean Association for Spatial Structures
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• v.12 no.2
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• pp.81-88
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• 2012

Cable dome structures are composed of cables-masts and the cables should be in pre-tension since a structure without pre-tension is not stable. Under the pretension, self equilibrium stress state is the main characteristic of a cable dome structure. In this paper, a new method based on the basic principle of closed force polygon for equilibrium system is proposed for the determination of self-equilibrium mode of cable dome structure. The proposed method which is called geometric method has the unique characteristic of visualization of the force mode needed for maintenance of self-equilibrium. The basic theory for a self equilibrium of structure is that the summation of forces at each joint without any external load should be zero. The simplicity of the method which involves only drawing close polygon with the aid of suitable CAD software has been illustrated by means of a example. The results compared with mechanical calculation and existed method and shows good agreement.

• Proceeding of KASS Symposium
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• 2005.05a
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• pp.52-66
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• 2005

Tension and Membrane have the potential to enable the realization of lightweight structures that have the attractive features of structures efficiency and aesthetical expression. Compared with pure (thorough-bred) tension structures such as cable net, air dome and tensegrity, so called hybrid tension structures such as beam string, tensegric system and other mixed structures have Potential still to be realized. After synnaruzubg the simple definition of tensegric structure, some holistic designs for hybrid tension structures completed recently in the author's practice are given.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.10a
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• pp.285-292
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• 2003

The soft structure can make large space more effectively, and its construction is easy and simple as well. However, it is not easy to realize this in the actual space. Therefore, two works are needed to be done for effective and accurate construction of soft structures. First, making a working scenario to complete the final objective form; second revising construction errors occurred in the middle of the actual works. These works are called constructional analysis. At this time, geometric nonlinearity should be considered to reflect the sensitivity by the initial stress of flexible structures, constructional analysis comes down to a nonlinear problem after all. This study approaches nonlinear constructional analysis with the numerical method for adjusting stress of cable-dome structures which are a soft structure system, and then verifies it.

• Journal of Korean Association for Spatial Structures
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• v.4 no.3 s.13
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• pp.65-75
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• 2004

A shell structure, having a curvature with a curved surface, is an extremely efficient mechanical creation regard to the external load. A basic structural resistance mechanism is the structural system, which is resisted the out-of-plane direction load by in-plane forces using the structure's curvature. Therefore, it has a merit to make thin and lightweight large spacial structures using minimum materials. Among the large spare structural system, the rapid development of the membrane structures, cable structures and the hybrid structures are watched recently. But, this kind of structural system shows the unstable phenomenon by snap-through or bifurcation according to the shape of structure, and the understanding of the collapse mechanism by this phenomenon is very important to the design process. In this study, I investigated the unstable characteristics of the Geiger-type, Zetlin-type and flower-type hybrid cable dome structures, which is the lightweight hybrid structures using compression and tension elements continuously, according to the difference of structural system.