What is steel beam and its advantages in construction?

Steel beam is one of the most important structural components in modern buildings. They support the weight of buildings, transfer loads, and ensure the stability and safety of buildings. From skyscrapers to industrial plants, from bridges to stadiums, steel beams are everywhere and play an indispensable role.

Definition and characteristics of steel beam

Steel beams are long structural components made of steel, which mainly bear loads perpendicular to their longitudinal axis. According to the cross-sectional shape, steel beams can be divided into I-beams, H-beams, channel steels and other types. Among them, I-beams are named because their cross-sectional shape resembles the Chinese character "工" and are the most commonly used form of steel beams.

Steel has excellent mechanical properties, and its tensile strength can reach more than 400MPa, which is more than 10 times that of concrete. The elastic modulus of steel beam is about 210GPa, which means that under the same load, the deformation of steel beams is much smaller than that of concrete components. These characteristics enable steel beam to withstand greater loads and span longer distances.

The production of steel beams adopts advanced rolling technology. Through high-temperature heating and continuous rolling, the steel billet is processed into the required cross-sectional shape. Modern steel enterprises use computer control systems to ensure that the dimensional accuracy and mechanical properties of steel beams meet the design requirements.

Advantages of steel beams in construction

Steel beams have an extremely high strength-to-weight ratio, which means that under the same load, the deadweight of steel beam is much smaller than that of concrete components. Taking a beam with a span of 30 meters as an example, the weight of a steel beam is only about 1/5 of that of a concrete beam. This feature significantly reduces the foundation load of the building and is particularly suitable for high-rise buildings and large-span structures.

The construction speed of steel beam is fast, and prefabricated assembly construction methods can be adopted. After the prefabricated steel beams in the factory are transported to the site, they can be quickly installed by high-strength bolt connection or welding. According to statistics, the construction speed of buildings with steel structures can be more than 30% faster than that of concrete structures.

Steel beams have good seismic resistance. Steel has good ductility and can absorb seismic energy through plastic deformation under the action of earthquakes. Studies in Japan have shown that buildings with steel beams are significantly less damaged in earthquakes than concrete buildings.

The durability and recyclability of steel beams are also significant advantages. After proper anti-corrosion treatment, the service life of steel beam can reach more than 50 years. When the building reaches the service life, the steel beams can be 100% recycled, which meets the requirements of sustainable development.

Application of steel beam in modern buildings

In high-rise buildings, steel beam usually form a frame structure with steel columns to form the main load-bearing system of the building. The Shanghai Tower adopts a steel frame-core tube structure, and its outer frame consists of giant steel columns and steel beams with a maximum span of 24 meters.

In large-span buildings, steel beams are more widely used. The National Stadium "Bird's Nest" adopts a complex steel truss structure with a maximum span of 340 meters. This structure not only meets the functional requirements of the building, but also creates a unique architectural aesthetic effect.

In industrial buildings, the advantages of steel beams are fully utilized. Single-story industrial plants usually use steel roof truss structures with a span of more than 30 meters. This structural form is convenient for equipment layout and production process organization, and has the advantages of fast construction and low cost.

Steel beams have a long history of application in bridge engineering. Modern large-span bridges mostly use steel box beam structures. For example, the maximum span of the steel box beam of the Hong Kong-Zhuhai-Macao Bridge is 460 meters. The light weight and high strength of steel beams make them the preferred material for large-span bridges.

With the advancement of construction technology, the application of steel beam will be more extensive. The research and development of new high-strength steels has further improved the bearing capacity of steel beams. The application of intelligent construction technology makes the processing and installation of steel beams more precise and efficient. In the future, steel beams will continue to play their unique advantages and create more amazing architectural miracles for mankind.