Steel bridge is a bridge span structure with steel construction of bridges, with high strength, high stiffness, relative to the concrete bridge can reduce the beam height and self-weight.
In 1874 the United States in Mississippi River built the world's first large-scale steel bridge - St. Louis (St. Louis) steel arch bridge, after the Second World War, steel bridge science and technology in the smelting of high-strength high-quality steel, welding technology to improve the orthogonal anisotropic steel bridge panels and high-strength bolts, as well as structural type of the diversification and so on, has developed greatly, prompting the large-span bridge. Diversification and other aspects, there has been a great development, prompting the widespread adoption of large-span steel bridges. Due to the high strength and superior performance of steel, the ratio of apparent density to allowable stress is small, so the spanning capacity of steel bridges is large. Steel bridge components manufacturing is most suitable for industrialization, transportation and installation are more convenient, shorter erection period, easy to repair and replace after damage.
Steel bridges have the following advantages: large spanning capacity, most suitable for non-industrialized manufacturing, easy transportation, fast installation, easy repair and replacement of steel bridge components.