We all know that the excellent structural performance of tube shapes in compression, torsion, and multi-directional bending has been fully demonstrated. Whether it's a reed in the wind, a bamboo in the rain, or a thigh bone that supports a person's weight, it's all round. Perhaps inspired by this, people combined the superior structural performance of circular pipe with the attractive architectural form to form the steel pipe structure. In recent years, circular pipe structures have been used in building construction, DAMS, Bridges, offshore platforms and tower masts.

At present, steel pipe structures used in engineering can be classified according to the shape of section, structural form and fabrication method. The steel tube structure can be divided into circular tube structure, square tube structure and other shapes. The superiority in appearance and mechanical performance is most common in circular and square tube structures. Pipe structure refers to the structure that adopts circular pipe and square pipe as members and connects pipe to pipe through intersecting welding. It can be divided into truss, net frame, frame and concrete-filled steel tube structure.

The advantages of the pipe structure are as follows. First, compared with the open section, the round pipe and square section have the characteristics of flat surface, no dead Angle and small external area, which is conducive to saving anti-corrosion and fireproof coating, and also easy to dust. Second, the wind resistance coefficient of steel tube section is small, which has significant advantages when it is exposed to fluid. Third, the internal space of steel tube structure can be used, filling concrete can not only improve the bearing capacity of the members, but also extend the fire resistance limit of the members. Four is in the pipe water, can use the internal water circulation for fire prevention and transmission of liquid.