Advantages of LSAW steel pipe in steel structure design are as follows:
(1) The cross section of the straight seam steel pipe has good geometric characteristics. The wall of the pipe is generally thin. The material of the section is distributed around the center of mass. The radius of gyration of the section is large and the torsional rigidity is large. As a compression, bending and bidirectional bending member, it has high bearing capacity and The straightness and cross-sectional dimensions of cold-bent pipes are more accurate than those of hot-rolled openings.
(2) In terms of anti-hydrodynamic properties, the cross section of the round pipe is the best, and the flow effect of wind and water is greatly reduced. The cross section of a rectangular tube is similar in this respect.
(3) The steel pipe has a closed section; under the same average thickness and cross-sectional area, the exposed surface area is about 50% to 60% of the opening part, which is beneficial to prevent corrosion and save paint.
(4) The connection of nodes is suitable for direct welding, which can save labor and materials without passing through gussets or other connecting parts.
(5) The appearance is more beautiful, especially the pipe frame composed of steel pipes, without redundant joints, and has a strong modern sense.
(6) If necessary, concrete can be poured into the pipe to form a composite member.
Due to the above advantages, compared with the structure made of the open part, the steel pipe structure can save about 20% of the steel in the industrial building and about 50% of the steel in the tower structure. According to the stress state of the components, supply conditions, production processing conditions and cost, the structure of the steel pipe can be a round pipe structure or a rectangular pipe structure, or a mixture of two steel pipes. When used in combination, the chord generally adopts a rectangular tube, and the web is a round tube. Sometimes, the strings can also be made of I-beams or H-beams, and the ribs can be rectangular or round tubes.
