A cable structure in the architecture field has a characteristic of being equipped with tremendously diversified functions, shapes and systems. As is seen in the design recommendation recently issued by the AIJ, data concerning designs andanalyses of materials and the cable structures has been well prepared. Accordingly, cables have been used in the construction of space structures as an important material. This paper describes the future development of the cable structure through thearrangement of subjects necessary to be solved for design and execution. Furthermore, results of past studies and real structures will be introduced in this paper.

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Recent progresses in cable-supported bridges have been remarkable: the suspension bridge has reached almost 2000m in span length and the cable-stayed bridge has jumped into the span range of almost 900m. This paper presents a review on cablesupported bridges. First the historical developments of cable-supported bridges are described. Next, the structural characteristics with emphasis on cable-stayed bridges are discussed in some detail. Discussions on the dynamics of cable-supported bridges, mainly under wind and earthquake disturbances, follow. Technical issues relevant to longer span bridges as well as issues which need more attention in cable-supported bridges are also presented.

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Cable and tensegrity structures are stabilized by introduction of prestresses. In the paper, the analytical andexperimental investigations of structures in which self-equilibrated stresses exist and which are stabilized by introducing prestresses are discussed. The conbination method to produce a stable structure with high rigidity is also described if there exist multiple independent self-equilibrated stress modes.

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The roof frame of THE FUKUOKA EXIBITION HALL that images sea waves is composed by the large scaled steel latiticed vault and the steel trussed ribs which strengthen the vaulted shell and are utilized as maintenance roots and mechanical uses. Prestressing forces has been introduced to the edge beams of the steel vault to reduce vertical displacement. The designmethods for the metal prestressing shell structure adopted here, the effect of prestressing and the steel trussed ribs, and so on are presented in this paper.

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"SKELSION" is a structural system consisting of tension strings combined with a skeleton. The "SKELSION" was developed for cases in which the BSS is supported by relatively thin columns. The wind-resisting and earthquake-resisting efficiency is improved by inserting a tension strings. In this paper, the loading test results obtained by using a small-scale model, the parametric study by making analyses, and the introduction of the design and the construction method for an actual structure, regarding the structural characteristics of the "SKELSION"', are investigated.

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The concept of 'Tensegrity' composed of the struts and the strings was invented by B. Fuller, and D. Geiger developed the system as Cable Dome with fabric roofing. In these structures, the importance of existence of the pre-stressing is indicated. In this study, we propose Tension Strut Dome (TSD) which is similar to a Cable Dome, but different with the origin of itsconcept. This structural system is composed of cable girder with radial form and tension ring truss. This paper reports an example of Tensegrity Tower and the structural principle of TSD which has the characteristics of the pre-stressing mechanism and the lift-up construction method.

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It is essential for design and maintenance of cable-stayed bridges to know long-term behavior due to visco-elastic deformation of cable strands, sockets, concrete members and ground settlement at the supports. This paper deals with a methodology to predict the long-term change of bridge geometry, particularly change of cable forces. First the full-scale long-term tension tests of various cable systems are introduced and the visco-elastic deformation of the cable strands andsockets are summarized. Secondly the method to determine the visco-elastic constants of cables and the finite element visco-elastic analysis together with the Laplace transformation are proposed. Analytical results by the proposed method are compared to the site measurement values and good agreement is made.

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Bending fatigue strengths of various types of bridge cables were examined by full-sized fatigue tests. Tested specimens are following four types of full-sized cable systems including sockets; (1) CFRC type rope for hangers of suspension bridges and (2) locked coil rope, (3) parallel wire strand(PWS), (4) non-grouted type PWS with high fatigue-strength sockets for stay cables of cable stay bridges. Characteristics of stress behaviours due to the difference of cable structures were also analized.

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The Akashi Kaikyo Bridge, whose main towers have already been completed, is now under construction. These towers are about 300 meters above sealevel, so that they are very flexible and their natural frequency i s lower than that of other towers of Honshu-Shikoku bridges. Consequently there arose an extremely important problem regarding how to control the vibration due to the wind. In the process of designing, a great variety of experimental and analytical studies were carried out. Based on their results, several types of damping device, such as TND, AND, and so on were installed on the towers to reduce the vibration. In this report, the outline of the vibration control design adapted for the towers will first be described, followed by the results of the field test and observation of the wind response performed on the towers under erection.

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A Cable-Reinforced Membrane Structures with Glulam Arches was constructed as the Hakuryu Dome in Daiwa-cho, Hiroshima Prefecture. This structure was realized by solving the following three issues.(1)Establisliment of methods of Cablenet design and construction(2)Development of Membrane joint detail which hides joint lines to show the roof as one Membrane(3)Establishment of design formula and construction method of Glued Laminated Timber joint, the Big Finger Joint, which doesn't use steel connections.This report describes the proposed design methods and the erection of the Hakuryu Dome.

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The energy-based analytical method for evaluating the modal damping of cable structures is proposed and its potential is discussed. After developing the damping theory of cables, the damping characteristics of stay cables, with and without cable-cross ties, in cable-stayed bridges, is investigated by using experimentally measured damping data as well as byconducting the damping analysis. It is concluded that the proposed analytical method of damping evaluation is very useful, and some peculiarities in modal damping of cable systems are clearly shown with theoretical bases. The modal damping of cable-stayed bridges is finally studied to show the coupling mode dependency of modal-damping characteristics.

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Stud connectors we are now using are welded verticaly to steel members and they resist, to the shear force by dowel action. We thought stud connectors can work more effectively by welded inclined to steel members because they resist directly to the shear force by their axial force . Here we examined the basic behavier of inclined studs by experiments and FEM analysis. And we obtained the results that positively inclined studs have higher stiffness and strength compared to vertical studs. If we use inclined studs where the shear force acts in the constant direction, the studs can work very effectively.

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One of the most important limit states of the member of the concrete structures under impact load like a roof of rock shed is the complete perforation of the member by the falling objects. It has been well known that the characteristics of concrete are improved by the use of fibers. However, the behavior of fiber reinforced concrete slabs under impact has not been clear adequately. Therefore, in the present paper, static and impact tests of the steel fiber reinforced concrete slabs areperformed. Fundamental characteristics of the failure types, energy of perforation, crack surfaces, developments of penetration up to complete perforation are investigated.

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The aim of this study is to make an analytical examination on how FRP tendons influence the mechanical behaviors of prestressed composite girders in both elastic and plastic regions, because there is still a necessity of providing an adequate amount of safety factor for structures using FRP materials. Furthermore, a method of the performance evaluations related to the load-carrying capacity and the deflection control of the prestressed composite girders with idealized FRP tendons is proposed based on the analytical results considered with some optimum parameters which are geometric parameters and material parameters. Finally, a design concept of the prestressed composite girder with FRP tendons is discussed in the construction of new bridges as well as in the bridge strengthening.

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Mechanical properties of cold roll-formed and press-formed steel square pipes are reviewed on the basis of numerous past experimental data. Major view points are strength, elongation, and notch toughness, which are related with the buckling and fracture behaviors of steel members in buildings excited by a strong earthquake. The increase in strength, the decrease inelongation, and the lack in notch toughness attributed to cold-forming processes are quantitatively and statistically demonstrated, based on which necessary design and fabrication remarks are provided, and future research needs are clarified.

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Despite of a certain advantage, universal mill plates produced by electric arc furnace process are rarely used for main members of Japanese railway bridges. It may be because effects oftheir characteristics, such as chemical components, corner drop of the plate edge, and thick mill scale, on their weldability and fatigue strength are not fully understood. Therefore, weldability tests are carried out using T joints for the universal mill plates. Then, fatigue tests of six types of tensile specimens and a full size truss member are carried out. All fatigue test results satisfy the corresponding allowable fatigue strength. It is concluded that universal mill plates satisfy the requirements of steel railway bridges.

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