1. What Is Steel Structure?
In academic terms, steel structure is a structure made mainly of steel, and is one of the main types of building structures nowadays. The characteristics of steel are high strength, light weight, good overall rigidity, and strong deformation ability, so it is particularly suitable for building large-span, ultra-high, and ultra-heavy buildings. Steel structure is a structure made of steel beams, steel columns, steel trusses, etc. made of steel and steel plates; each component or part is connected by welds, bolts or rivets.
2. Characteristics of Steel Structure
1. Steel has good toughness, good plasticity, uniform material, high structural reliability, suitable for bearing impact and dynamic loads, and has good seismic resistance. The internal structure of steel is uniform, close to isotropic homogeneous body. The actual working performance of steel structure is more in line with calculation theory. Therefore, steel structure has high reliability.
2. The material has high strength, light weight, high strength of steel, and high elastic modulus. Compared with concrete and wood, the ratio of its density to yield strength is relatively low. Therefore, under the same stress conditions, the cross-section of steel structure components is small, the deadweight is light, and it is easy to transport and install. It is suitable for structures with large spans, high heights, and heavy loads.
3. The steel structure has good sealing performance. Since the welded structure can be completely sealed, it can be made into high-pressure containers, large oil pools, pressure pipelines, etc. with good air tightness and water tightness.
4. The steel structure is heat-resistant but not fire-resistant. When the temperature is below 150℃, the properties of the steel change little. Therefore, the steel structure is suitable for hot workshops, but when the surface of the structure is subjected to heat radiation of about 150℃, it must be protected by heat insulation boards. When the temperature is 300℃-400℃, the strength and elastic modulus of the steel both decrease significantly. When the temperature is around 600℃, the strength of the steel tends to zero. In buildings with special fire protection requirements, steel structures must be protected by refractory materials to improve the fire resistance level.
5. The corrosion resistance of steel structures is poor, especially in humid and corrosive media environments, and they are prone to rust. Generally, steel structures need to be rust-free, galvanized or painted, and maintained regularly. For offshore platform structures in seawater, special measures such as "zinc block anode protection" are required to prevent corrosion.
6. The manufacturing and installation of steel structures are highly mechanized, and steel structure components are easy to manufacture in factories and assemble on site. The finished products of mechanized steel structure components manufactured in factories have high precision, high production efficiency, fast assembly speed on site, and short construction period. Steel structure is the most industrialized structure.
3. The Development History of Steel Structure
China had made outstanding achievements in iron structure in the early days, but due to the constraints of the feudal system and underdeveloped science, China has been at the level of iron structure construction for more than 2,000 years. It was not until the end of the 19th century that China began to adopt modern steel structure.
After the founding of New China, the application of steel structure has made great progress, far exceeding the past in both quantity and quality. After 2000, China's national economy has grown significantly, national strength has been significantly enhanced, and steel production has become a world power. Around 2008, driven by the Olympic Games, there was a boom in steel structure construction.
Strong market demand has promoted the rapid development of steel structure buildings, and a large number of steel structure venues, airports, stations, and high-rise buildings have been built one after another. Among them, some steel structure buildings have world-class production and installation technology, such as the Olympic National Stadium. We have reached a high level in design, manufacturing, and installation technology, and mastered the design and construction technology of various complex buildings.
