Requirements and precautions for material selection in steel structures

【 1 】 Requirements for material Selection of Steel structures
Due to the differences in the parts used and functions, the materials of the steel selected are also not the same. Such as steel with medium toughness required for machine parts; The materials used in the lathe processing workshop; Materials selected for petrochemicals; There are many types of steel, but few can meet the requirements for structural steel. When choosing steel for building structures, the following points should be met:
The selected steel means choosing steel with high tensile strength and yield point. To increase the yield strength of steel, profiles with smaller cross-sections can be selected. Reducing the weight of the steel structure itself leads to a decrease in the usage of steel and lowers the investment cost of steel structures in Beijing. Increasing the tensile strength of steel can enhance the lateral thrust resistance of the structure.
Sufficient deformation capacity. That is, it has good plasticity and toughness. Steel has good plasticity. When it is damaged by external force loads, the failure points are easy to be found. It has reduced the hazard of sudden collapse of steel structure buildings. Steel with good plasticity has the ability to reduce the internal stress values caused by sudden loads. And it will cause local deformation and relieve stress. When subjected to vibration loads, it can consume most of the vibration force, significantly reducing the risk of sudden structural damage. When plastic design is involved in steel structure buildings in earthquake-prone areas, the deformation of steel is of vital importance and is related to the entire building.
Good processing performance. Steel can be cold-pressed and forged or hot-rolled, and it also has weldability.
When processing, it is necessary to maintain the inherent properties of the steel as much as possible and not to reduce its own performance due to the adoption of processing techniques.
Otherwise, the structure of the entire building will bring considerable hidden dangers.
The steel used in the load-bearing structure of steel structures should have certificates of conformity for yield strength, elongation after fracture and tensile strength.
【 II 】 Precautions for Steel Structure Installation
Steel structure manufacturers not only undertake the design and production of various components for steel frame structures, but also take on the overall installation of steel frame structures. Generally, before the construction of steel structure projects, various convenient measurements are carried out and pre-installation tests are conducted. There are no problems throughout the entire construction process. The key points of steel frame structure installation mainly include the following aspects:
The prefabrication of steel prefabricated components shall be carried out on the steel platform in accordance with the installation sequence and processing technology regulations, and the quality of welding and manufacturing shall be ensured.
The distance between the splicing joint of the flange plate of the channel steel and the splicing joint at the beam end should exceed 200mm. The length of the flange plate splicing should not be less than twice the width of the plate. The total width of the beam end splicing should not be less than 300mm, and the length should not be less than 600mm.
3. To facilitate welding and ensure welding quality, it is advisable to check and weld the reinforcing plates, connecting plates, spacers, and cantilever beams (beams) on the vertical poles and load-bearing beams on the road surface steel platform in accordance with the specifications of the construction drawings as much as possible.
4. For the steel prefabricated components prefabricated on the steel platform, in addition to being fabricated and assembled in accordance with the construction drawings and standards, the on-site installation process performance and changes in installation specifications should also be taken into consideration.
After the installation is completed, measurements and inspections at all levels should be carried out.