Poor corrosion resistance: Especially in humid and corrosive environments, steel structures are prone to rusting. Generally, rust removal, galvanizing or coating are required, and regular maintenance is necessary. For structures exposed to the atmosphere, such as bridges, more attention should be paid to protection.
Steel structures have the following main characteristics:
High material strength and light weight: Steel has high strength and high elastic modulus. Compared with concrete and wood, its density to yield strength ratio is relatively low. Therefore, under the same stress conditions, the components of steel structures have small cross-sections, light self weight, and are easy to transport and install, making them particularly suitable for structures with large spans, high heights, and heavy loads.
Good toughness and plasticity: Steel has good toughness and plasticity, can withstand large impacts and dynamic loads, and has good seismic performance. The internal structure of steel is uniform and close to isotropic homogeneous body, and the actual working performance is in good agreement with the calculation theory, therefore the structural reliability is high.
High degree of mechanization in manufacturing and installation: Steel structural components are easy to manufacture in factories, with fast assembly speed on construction sites, high production efficiency, and short construction periods. Mechanized manufacturing of steel structural components in factories has high precision and fast assembly speed on construction sites, making it suitable for industrial production.
Good sealing performance: The welded structure can achieve complete sealing, suitable for high-pressure vessels, large oil tanks, pressure pipelines, etc. that require airtightness and water tightness.
Heat resistant but not fire-resistant: The properties of steel change very little at temperatures below 150 ℃, making it suitable for hot workshops. But when the temperature exceeds 150 ℃, insulation boards need to be used for protection. When the temperature reaches 300 ℃ -400 ℃, the strength and elastic modulus of the steel significantly decrease, and the strength tends to zero at 600 ℃. Therefore, fire prevention measures must be taken for steel structures in buildings with special fire prevention requirements.
Poor corrosion resistance: Especially in humid and corrosive environments, steel structures are prone to rusting. Generally, rust removal, galvanizing or coating are required, and regular maintenance is necessary. For structures exposed to the atmosphere, such as bridges, more attention should be paid to protection.
Low carbon, energy-saving, and green environmental protection: Steel structures can be reused, with minimal environmental impact during construction and demolition, meeting the requirements of low-carbon, energy-saving, and green environmental protection.
These characteristics make steel structures widely used in large factories, venues, super high-rise buildings, bridges and other fields.