The steel structure engineering quality inspection unit, steel structure, as its name implies, is a type of structure produced and processed by using steel as the main raw material, which is a very important building type in the field of construction today. The construction type of steel structure is widely recognized by the construction industry for its lightness, high strength, and deformation resistance, which are unique to its steel material, and is increasingly used in various construction projects. The utilization rate of steel structure buildings in a country has become a symbol of the country's economic development level. The more steel structure facilities it has, the higher the country's economic and technological level. In China, with the completion of the steel structure of the 2008 Olympic Games "Bird's Nest", the steel structure has become a highly sought after type of building. The stability of the steel structure can be divided into two cases: the overall stability of the structure and the stability of the component itself. The overall stability of the structure is mainly ensured by the structural support system in the longitudinal direction of the structure, such as the support between steel columns, horizontal support and vertical support of the upper and lower chords of the steel roof truss. Whether the supporting system can reliably transfer the longitudinal horizontal load (wind load, earthquake load, factory crane load, etc.) of the structure. The lateral direction depends on the rigidity of the structure itself (frame or row) to ensure that the structure itself can reliably transfer the horizontal load of the structure. The stability of the component itself is mainly guaranteed by the rigidity of the component parts. It is necessary to ensure that the component itself and its components (rods or plates) do not buckle and lose stability under the load (this situation mainly occurs when Press or bend the member).