The steel used in high-rise buildings is subject to complex stress conditions, and it is required to have the characteristics of high safety and reliability, long service life, and the ability to resist damage of a certain seismic intensity. This determines that the steel plates used in high-rise building structures require certain special properties, mainly The following points:
(1) It can resist the damage of a certain earthquake force, and it must be able to resist earthquakes and earthquakes. For this reason, the steel plate must not only have sufficient tensile strength and yield strength, but also have a lower yield ratio. The low yield strength ratio can make the material have good cold deformation ability and high plastic deformation work, absorb more earthquake energy, and improve the earthquake resistance of buildings.
(2) To have good welding performance, so that no preheating is required before welding and no heat treatment is required after welding, so as to facilitate on-site welding, thereby reducing labor intensity and improving labor efficiency.
(3) It must have high plasticity and toughness so that the steel plate has good mechanical properties.
(4) To have a smaller yield strength fluctuation range. When the fluctuation range of yield strength is large, the matching of yield strength between various parts of the building may be different from the design requirement value, which is prone to local damage and reduces the earthquake resistance of the building. Therefore, the Japanese standard stipulates that the yield strength fluctuation range is not greater than 120MPA.
(5) Within the range of beam and column joints connected by welding, when the joint constraints are strong and bear the tensile force along the thickness direction of the plate, the steel plate must have a certain level of lamellar tear resistance.