A steel structure refers to a load-bearing structural system that primarily adopts steel profiles (such as H-beams, I-beams, angle steels, channel steels, steel plates, steel pipes, round bars, etc.) as its core stress components. These members are connected and formed into an integral structure through reliable connection methods including high-strength bolt connection, welding, and ordinary bolt connection, which together bear the vertical loads (dead weight, live load, snow load, etc.) and horizontal loads (wind load, seismic action, crane braking force, etc.) of buildings or engineering facilities.

As one of the most important structural forms in modern engineering construction, steel structures are widely used in various industrial, civil, and public buildings, as well as large-scale infrastructure projects. They are characterized by industrialized production, standardized design, prefabricated manufacturing, and on-site assembly, forming a complete engineering system integrating design, processing, transportation, and installation.