Development and Practice of Processing and Manufacturing Technology for Complex Building Steel Structures

Compared with traditional concrete structures, steel structures have gradually been widely used in the construction industry due to their light weight, high strength and easy forming. Since the end of the 19th century and the beginning of the 20th century, the application of steel structure has been expanding, especially in high-rise buildings and stadiums. The development of steel structure in China started late, but with the rapid advancement of urban construction, especially the opportunity of the 2008 Beijing Olympic Games, numerous innovative buildings have emerged, which has promoted the progress of steel structure technology.
There is no strict standard for the definition of complex architectural steel structure, and this paper discusses it from the perspective of processing and manufacturing process. The development of complex architectural steel structure in China can be roughly divided into three stages: the first stage (1990s): projects such as Shanghai Grand Theatre used welded box and steel pipe truss structures with complex configurations. The second stage (from the early 2000s to the mid-2010s): the construction of projects such as the National Stadium marked the rapid development of steel structures for complex buildings. Phase III (more than a decade ago): With technological innovation, all kinds of complex steel structures have emerged, such as the Shanghai Centre Tower.
Complex steel structure is mostly used for the exposed components of special architectural shapes, or the node structure is particularly complicated due to the complexity of the building structure. Common applications include shaped cross-section members, space curved surface members and so on. The processing and manufacturing technology of complex steel components mainly focuses on the following aspects: deepening design technology: from manual drawing to CAD, and then to the establishment of BIM model, to improve the design efficiency and accuracy. Development of special equipment: such as multi-dimensional coherent line cutting machine and large-stroke end milling machine, etc., to improve processing accuracy and efficiency. Shaped cross-section member forming technology: adopting a variety of processes, such as cold processing, hot processing and sample box testing, to meet the processing needs of complex members. Steel pipe bending forming technology: including hot bending and cold bending methods, applicable to the processing of steel pipes with different curvature radii. Processing of large-caliber steel pipes and conical pipes: adopting rolled and pressed forming processes, applicable to steel pipes of different calibers and shapes.