Design of Space Tube Trusses for Long Span Steel Structures ( Part 1)

The steel structure tube truss technology has been popular abroad for many years. While the Chinese construction industry is experiencing rapid development, it is gradually paying attention to the building roof system. On this basis, steel structure tube truss technology has been deeply researched, developed and applied. Next, we explore this design structure.

1.Preliminary understanding of tube truss structure

With the development of technology, the scope of application of steel pipe structures in today’s buildings has expanded from the scope of large scale construction projects to the scope of industrial buildings and civil buildings. For example, the stadiums in Shanghai and Changchun, the airport terminals in Chengdu, the ski resort in Harbin, the Yangzhou Stadium, the Shanghai Yangzigang Bridge, the Guangzhou International Convention and Exhibition Center, and the Laoshan Velodrome of the Beijing Olympics, etc., have chosen the design structure of steel structure space tube truss of the roof system.

Tube trusses are generally divided into two types of pipe truss structures, planar and space,according to the different layout of the rod frame and the different force characteristics. As the name implies, the planar truss structure is that the upper, lower chord and web members are all in the same plane. The external rigidity of this structure is poor. The upper and lower chord members of the space truss structure are usually on a triangular cross-section. This structure has a large span, high stability, and usually has a more aesthetic appearance. When the external support cannot be arranged, a triangular truss with high stability is used to construct a space with a large span. This structure reduces the number of supporting parts, so it is more economical.

For the type of cross-section of the connecting member of the pipe truss, the commonly used ones are circular, square and rectangular. The corresponding truss types are also different for the cross-section of different graphics. If the cross-section of the connecting part is circular,choose CC type truss. If the cross-section of the connector is square,choose the RR type truss. If the cross-section of the connector is rectangular, choose the RC type truss.

The type of chord determines the shape of the truss, which can basically be divided into two types: linear truss and curved truss. Among them, the curved truss can better reflect the aesthetics of the building, and is also most commonly used in the construction process. In order to obtain the best architectural effect with the smallest cost expenditure, in the design process of the curved pipe truss structure, the rods are still in the form of straight rods, and the broken lines are approximated to replace the curves.

The steel pipe truss structure has beautiful appearance, low economic cost, and reasonable force than other materials. It is these relative advantages that make steel pipe trusses most commonly used in construction. A large number of construction engineering practices can prove that the use of steel pipe structures meets the basic principles of architecture on the one hand, and meets the basic requirements of architecture on the other hand, and is consistent with the latest design concepts.

2.Development status of space tube truss structure

Many modern large-scale buildings are constructed with steel structures, and with the continuous deepening and development of the construction industry, architectural concepts have undergone earth-shaking changes and innovations. In the application and practice of steel structures, there have been many similar large-span structures., Steel structure buildings with relatively complex and changeable spatial shapes. The design of these new steel structure buildings also provides a basis for the optimization and innovation of steel components. In recent years, large-scale sports venues, cultural venues, and exhibition halls such as the Water Cube, the National Grand Theater, and the new office building of China Central Television have all used large-span and complex space steel structures. To serve as the building’s own roof structure system.

Nowadays, the scientific and technological gold content of the architectural level has become the standard to measure the architectural level of a country. Among them, the development of space structure technology determines the scientific and technological content of the architectural level. my country’s construction industry has never stopped the pace of research on long-span spatial structures, and the corresponding construction technology has also made a qualitative leap. Large-span space tube trusses have played an irreplaceable role in the construction of important national venues. However, due to differences in spans, truss sections, and specifications, there are more or less differences in wall thickness butt joints and K-shaped joints between buildings.