connection method of steel structurewelding connection or bolt connectionSteel structure design common norms are as follows"Steel Design Code" (GB50017-2003)"Cold-formed steel structure technical specifications" (GB50018-2002)"Construction Quality Acceptance of Steel" (GB50205-2001)"Technical Specification for welded steel structure" (JGJ81-2002, J218-2002)"Technical Specification for Steel Structures of Tall Buildings" (JGJ99-98)The characteristics of steelLight weight steel structureHigher reliability of steel workSteel anti-vibration (earthquake), impact and goodSteel structure for a higher degree of industrializationSteel can be assembled quickly and accuratelyLarge steel interior spaceLikely to cause sealing structureSteel corrosivePoor fire-resistant steelRecyclable steelSteel shorter durationCommonly used steel grades and performance of steelCarbon structural steel: Q195, Q215, Q235, Q255, Q275, Q345,etc.High-strength low-alloy structural steelQuality carbon structural steel and alloy structural steelSpecial purpose steelMarketProducts have been all over the country more than 20 provinces, municipalities andautonomous regions,and have been exported to Europe, North America,the Middle East, Africa, Asia and other countries and regions.