1. High-rise steel structure technology
According to the building height and design requirements, frame, frame support, cylinder and giant frame structures are adopted respectively, and its components can be made of steel, stiff reinforced concrete or steel tube concrete. Steel components are light in weight and have good ductility, and can be made of welded steel or rolled steel, which is suitable for high-rise buildings; stiff reinforced concrete components have high stiffness and good fire resistance, and are suitable for mid-to-high-rise buildings or bottom structures; steel tube concrete is easy to construct and only uses Yu column structure.
2. Space steel structure technology
The space steel structure has light weight, high stiffness, beautiful appearance and fast construction speed. Ball-node flat-plate grids with steel pipes as rods, multi-layer variable-section grids and grid shells are the structural types that use a large amount of space steel structures in my country. It has the advantages of high spatial rigidity and low steel consumption. It has complete CAD procedures for design, construction and inspection. In addition to grid structures, space structures also include long-span suspension cable structures, cable-membrane structures, etc.
3.Light steel structure technology
It is accompanied by a new structural form consisting of walls and roof envelopes made of lightweight color coated metal sheet. It is a light steel structure system composed of large-section thin-walled H-shaped steel wall beams and roof purlins welded or rolled by steel plates above 5mm, flexible support systems made of round steel and high-strength bolt connections. The column spacing can be from 6m to 9m, and the span can be up to 30m or more, the height can reach more than ten meters, and light cranes can be installed. The amount of steel used is 20~30kg/m2. There are now standardized design procedures and chemical production enterprises. The products have good quality, fast installation speed, light weight, and construction is not subject to seasonal restrictions. It is suitable for various light steel frame prefab workshop.
4. Steel concrete composite structure technology
The beam and column load-bearing structure composed of shaped steel or steel management and concrete components is a steel-concrete composite structure, and its application scope has been increasingly expanded in recent years. The composite structure has the advantages of both steel and concrete. It has high overall strength, good rigidity, and good seismic resistance. When it is constructed with outer concrete, it has better fire resistance and corrosion resistance. Combined structural components can generally reduce the amount of steel used by 15 to 20%. Combined floor slabs and steel tube concrete components also have the advantages of less or no formwork, convenient and fast construction, and have great potential for promotion. It is suitable for frame beams, columns and floor coverings of multi-story or high-rise buildings with larger loads, and industrial building columns and floor coverings.
5. High-strength bolt connection and welding technology
High-strength bolts transmit stress through friction and are composed of three parts: bolts, nuts and washers. High-strength bolt connections have the advantages of simple construction, flexible disassembly, high bearing capacity, and good self-locking properties. They have replaced riveting and partial welding in engineering and become the main connection method in the production and installation of steel structures. For steel components made in the workshop, thick plates should use automatic multi-wire arc submerged welding, and box column partitions should use fusion nozzle electroslag welding and other technologies. During on-site installation and construction, semi-automatic welding technology, gas shielded welding flux-cored wire and self-shielded flux-cored wire technology should be used.
6. Steel structure protection technology
Steel structure protection includes fire protection, anti-corrosion, and anti-rust. Generally, there is no need for anti-rust treatment after fire-retardant coating treatment. However, anti-corrosion treatment is still required in buildings with corrosive gases. There are many types of fire retardant coatings in China, such as TN series, MC-10, etc. Among them, MC-10 fire retardant coatings include alkyd enamel paint, chlorinated rubber paint, fluorine rubber paint, and chlorosulfonated paint. During construction, appropriate coatings and coating thickness should be selected based on the steel structure type, fire resistance grade requirements and environmental requirements.
