The Study On The Stiffness Performance Of Steel-Pipe Trusses With Curved Chords

Steel Pipe Structures (SPS) have been widely used in civil engineering. Together with the small-sized steel pipes which have been adopted in steel trusses and lattice shells in a large amount, the curved steel pipes working as chords of trusses are also more and more used in a few large-span steel structures. Because the bending process of steel pipes possesses the special features such as high producing efficiency and low energy consume and less production cost and so on,it can be used in several kinds of structures. On the other hand, it's obviously that cold-bended steel pipes have their mechanical properties varied greatly. The more the steel pipes are bended, the greatly their properties are changed. Normally, the variety of mechanical properties are harmful to the mechanical characteristic of structure and its members. If this kind of variety is neglected, steel pipes might work in the status of uncertainty and danger. Sometimes it would make the structure failed. Combining with the analysis and calculation of the roof steel structure of Guangzhou International Convention and Exhibition Center, three following parts are studied and discussed.1. With regard to the approximate analysis of arc member,on condition that the ratio of arc's height to length of chord is limited to about 1/12, a group of piecewise linear curve elements are put forward to imitate the stiffness performance of arc element.With this method,only one additional node should be set up to make use of existing program to calculate arc member approximately.2. With regard to the change of mechanical properties of cold or heat-bended steel pipes, a series of experiments for bended steel pipes and their mechanical properties are carried out to consider the relation...