(1) The node connection is suitable for direct welding, and it does not need to pass through the node plate or other connecting parts, which saves labor and materials.

(2) When necessary, concrete can be poured into the pipe to form a composite component.

(3) The geometric characteristics of the pipe section are good, the pipe wall is generally thin, the material of the section is distributed around the centroid, the radius of gyration of the section is large, and it has strong torsional rigidity; as compression, compression, and bidirectional bending component, its The bearing capacity is higher, and the straightness of cold-formed pipes and the accuracy of cross-sectional dimensions are better than those of hot-rolled open cross-sections.

(4) The appearance is more beautiful, especially the pipe truss composed of steel pipe members, there is no redundant joint connection, and the modern feel is strong.

(5) In terms of anti-hydrodynamic characteristics, the cross-section of the round tube is better, and the effect of wind and water flow is greatly reduced. The rectangular tube section is similar to other open sections in this respect.

(6) Large-diameter steel pipes have closed cross-sections; when the average thickness and cross-sectional area are the same, the exposed surface area is about 50% to 60% of the open cross-section, which is beneficial to corrosion prevention and can save coating materials.