In recent years, with the continuous growth of China's steel production, steel structure with its own advantages, in the construction of a growing proportion, steel tube structure has also made a big breakthrough. The biggest advantage of the steel tube structure is that it can perfectly combine the functional requirements, aesthetic requirements and economic benefits of the building. The tubular truss structure in the steel tube structure is favored by people because of its unique advantages.

Compared with the net truss structure, the tubular truss structure eliminates the lower chord longitudinal bar and the ball joints of the net truss, which can meet the requirements of various architectural forms, especially the construction of arch and arbitrary curve shape is more advantageous than the net truss structure. It has the same stability in all directions and saves material consumption. Steel tube truss structure is developed on the basis of truss structure. Compared with truss structure, it has its unique advantages and practicability.

With the traditional open section (h-beam and I word steel), compared to steel truss pipe truss structure section material around the neutral axis is evenly distributed, the cross section at the same time has good compressive and flexural bearing capacity and large stiffness, no node board, simple structure, pipe truss structure is the most important of good appearance, easy to shape have certain adornment effect. The overall performance of the tubular truss structure is good, the torsion stiffness is large, and the appearance is beautiful. The steel tube roof frame made of cold-formed thin-wall steel has the advantages of light structure, good rigidity, saving steel, and can give full play to the strength of materials, especially in the compression bar and support system controlled by the ratio of length to fineness, which is more economical. At present, the buildings adopting this structure are basically public buildings. The structure has beautiful shape (can be built flat, arch, arbitrary curve), convenient production and installation, good structural stability, roof stiffness, good economic effect and other characteristics.

The truss refers to the lattice structure which is composed of the rods connected with each other at the end. In most cases, the truss members are only subjected to axial tension or pressure, and the stress is evenly distributed on the section, so it is easy to play the role of materials. It is easy to form various shapes to adapt to different USES, such as simply supported truss, arch, frame and tower, etc., so truss structure is widely used in many large-span stadium buildings, such as exhibition center, stadium or some other large public buildings.

Most of the rods in the truss structure are connected at the joints by welding. Before welding, cutting of the web and chord is required according to the welding shape of each rod to be welded in advance, which requires intersecting line cutting and grooving of the chord at the end of the web. Because of the intersecting form of the intersecting lines between the bars and the bars in the truss structure, the shape of the end section of the bars is relatively complex, so in the actual cutting processing, the two methods of mechanical automatic cutting processing and manual cutting processing are generally adopted.

Compared with the net truss, the tube truss has fewer bars, beautiful joints and no large ball joints. By using the long-span space tube truss structure, various light-weight long-span structures can be built. In public civil buildings, especially in the construction of large-scale exhibition and sports venues, it has a wide application prospect.