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1. High material strength and light weight

Steel strength is higher, the elastic modulus is also high. Compared with concrete and wood, the ratio of its density and yield strength is relatively low, so under the same stress condition of steel structure components section small, light weight, easy to transport and installation, suitable for large span, high height, heavy bearing structure.

2, steel toughness, good plasticity, material uniformity, high structural reliability

Suitable for bearing impact and dynamic load, with good seismic performance. The internal structure of steel is homogeneous, close to isotropic homogenizer. The actual working performance of steel structure accords with the calculation theory. Therefore, the steel structure has high reliability.

3. High mechanization degree of steel structure manufacturing and installation

The steel structural members are easy to assemble in the factory and the construction site. Factory mechanized manufacturing steel structure components finished products of high precision, high production efficiency, site assembly speed, short construction period. Steel structure is the most industrialized structure.

4. Good sealing performance of steel structure

Due to the welding structure can be completely sealed, can be made into air tightness, water tightness are good high pressure vessels, large oil pool, pressure pipeline.

5. The steel structure is heat resistant and refractory

When the temperature was below 150 ℃, the steel properties changed little. Thus the steel structure is suitable for the hot shop, but the structure surface at the thermal radiation of about 150 ℃, to adopt heat insulation board to protect it. Temperature at 300 ℃ to 400 ℃. The steel strength and elastic modulus were decreased significantly, the temperature about 600 ℃, the steel strength tends to zero. In buildings with special fire protection requirements, the steel structure must be protected by refractory materials to improve the fire resistance grade.

6. Poor corrosion resistance of steel structure

Especially in humid and corrosive medium environment, easy to rust. General steel structure to rust, zinc or paint, and to regular maintenance. For the structure of offshore platform in sea water, special measures such as "zinc block anode protection" should be adopted to prevent corrosion.

7, low carbon, energy saving, green, reusable

The demolition of the steel structure will produce almost no construction waste, and the steel can be recycled.