In the past 20 years, the steel pipe structure has been rapidly developed at home and abroad. Has been widely used in modern industrial buildings, warehouses, stadiums, exhibition halls, stadiums, docks, railway stations, office buildings, hotels and other buildings. Due to its good performance, it is more and more widely used at home and abroad. The tube structure can be divided into a beam structure and an arch structure from the structure. From the layout can be divided into planar tube structure and space tube structure. Mainly used for two sections of the tube: tube and square tube. The pipe is connected to the pipe by a cross-weld, because the treatment makes the structure more neat and beautiful. The hybrid structure system formed by the combination of the tubular structure and the cable, such as the aforementioned beam string structure, fully exerts the superiority of different materials or components, and is the direction of future structural development. Pipe racks have been widely used in large-span facilities such as gymnasiums, terminal buildings, convention centers, and entertainment centers.
The pipe node is a very important issue in the pipe structure, including local stress and strain analysis of pipe joints, failure mechanism research, elasto-plastic analysis, design parameter research, influence of load and branch constraints, and fatigue life. Due to the different locations of the nodes in the structure and the different forms of the connecting members, their stress conditions and construction requirements are also different. Pipeline nodes have a lot of structure, and new structures form new nodes. The current research results cannot cover all the forms of tube nodes. For example: ASTM A500 square tube is in charge, and the bearing capacity of the branch tube to the branch tube seldom involves people.