Why doesn't the light steel structure house rust?

Summarizing the reasons for the rapid development of light steel structures in North America, it can be concluded that the technology is mature and reliable, the structural system flexibility is conducive to construction and commercial development, the construction economy is high, and the technology is advanced in line with the trend of environmental protection, energy saving and sustainable development. The technology and product configuration of light steel structures are extremely mature and have a high level of industrialization. They are the crystallization of the development of construction technology and building materials industry in North America in the past century. The corrosion resistance of galvanized steel sheet used in building structures is excellent and durable, and its service life under normal application environment is 275 years. The seismic performance of light steel structure is much better than that of traditional concrete and brick-concrete houses. At the same time, due to the light weight of the light steel structure, the unit area component is only 1/4 of the brick-concrete layout component of the same area, so its foundation is easy to handle and suitable for most geological environments. Steel layout houses are no longer as worried about termite persecution as wooden layout houses. Why not rust? Light steel structure is a young and vigorous steel structure system, which has been widely used in ordinary industrial and agricultural, commercial, and service buildings, such as office buildings, villas, stacks, stadiums, entertainment, tourism buildings and low- and multi-storey buildings. Residential buildings, etc. What is the difference between light steel structure and heavy steel structure? The identification of the structure as heavy steel and light steel structure does not have the same standard, and many experienced designers or project managers often cannot explain it completely, but we can comprehensively consider and conclude with some data:</p>1. The lifting weight of the factory building: greater than or equal to 25 tons, it can be considered as a heavy steel layout. 2. The amount of steel used per square meter: if it is greater than 50KG/M2, it can be considered as a heavy steel layout. 3. Thickness of steel plate for important components: greater than or equal to 10MM, and light steel layout is used less. The characteristics of light steel structures Developed countries are using non-residential buildings very rapidly, and are expanding to multi-storey residential buildings. Non-living buildings are mainly composed of door-type light steel structures with the following four floors, and the span is usually greater than 20m. Temporary housing, hangar, etc. Light steel structure shelter buildings are generally used for multi-storey (4-6 floors) and high-rise buildings with a height of less than 24m (7-9 floors). By adding energy-dissipating components such as energy-dissipating supports, the sheltered light steel structure can also be used for higher floors. The light steel structure for shelter is mostly made of a frame structure composed of hot-rolled H-beam, the joints are connected by high-strength bolts (supplemented by welding), the floor slab is mostly a reinforced concrete structure that replaces the formwork with a profiled steel plate substrate, and the roof panel and the outer wall are mostly used. The black and white coated steel plate that integrates thermal insulation and waterproofing is adopted, and waterproof lightweight wallboards are mostly used for household walls.