(1) Weld connection: weld connection is the main connection method of steel structure at present. Its advantages are simple structure, steel saving, convenient processing, easy to use automatic operation, not suitable for directly bearing dynamic load structure, other cases can be connected by welding.
(2) Rivet connection: due to the complex structure and large amount of steel, riveting is rarely used now. Because of its good plasticity and toughness, reliable force transmission and easy inspection, rivet connection is still used in some heavy-duty and dynamic load bearing structures.
(3) Bolt connection: bolt connection is divided into ordinary bolt and high strength bolt. The common bolt is simple in construction and convenient in disassembly and assembly. Ordinary bolts are generally made of Q235. High strength bolts are made of alloy steel. The manufacturing process of high strength bolts is accurate, with many operation procedures and high requirements. At present, it has been widely used in bridges, large-span buildings and industrial plants in China.