H-shaped steel is an economical cross-section and high-efficiency profile with more optimized cross-sectional area distribution and more reasonable strength-to-weight ratio. It is named because its cross-section is the same as the English letter "H". Since all parts of H-shaped steel are arranged at right angles, H-shaped steel has the advantages of strong bending resistance in all directions, simple construction, cost saving and light structural weight, and has been widely used.

1. Application scope of H-shaped steel

H-shaped steel is mainly used as beam and column components in industrial and civil structures.

◆ Steel structure load-bearing brackets for industrial structures

◆ Steel piles and supporting structures for underground projects

◆ Industrial equipment structures such as petrochemical and electric power

◆ Long-span steel bridge components

◆ Frame structure for shipbuilding and machinery manufacturing

◆ Girder supports for trains, cars and tractors

◆ Port conveyor belt, high-speed baffle bracket

H-shaped steel is an economical cross-section steel that is widely used in industry, construction, bridges, oil drilling platforms, etc. It is predicted that my country's demand for H-shaped steel will be about 2.5 million tons in 2005 and 5 million tons in 2010. However, currently my country The annual production capacity of H-shaped steel is 1.2 million tons, and the market demand is very huge.

2. Introduction to H-shaped steel classification

H-shaped steel is divided into two types: hot-rolled H-shaped steel and welded H-shaped steel (H). Hot-rolled H-shaped steel is further divided into wide-flange H-shaped steel (HW), medium-flange H-shaped steel (HM) and narrow-flange H-shaped steel (HN). Three types. 

HW is an H-shaped steel whose height and flange width are basically equal; it is mainly used for steel core columns in reinforced concrete frame structure columns, also called stiff steel columns; it is mainly used for columns in steel structures.

HM is the ratio of H-shaped steel height to flange width, which is roughly 1.33~~1.75. Mainly used in steel structures: used as steel frame columns and frame beams in frame structures that bear dynamic loads; for example: equipment platforms

HN is an H-shaped steel with a height and flange width ratio greater than or equal to 2, mainly used for beams; the use of I-shaped steel is equivalent to HN-shaped steel;

The main materials of H-shaped steel are Q235B, SM490, SS400, Q345, Q345B, etc.

3. Structure introduction

H-shaped steel is a new type of economical construction steel. H-shaped steel has an economical and reasonable cross-section shape and good mechanical properties. During rolling, the extension of each point on the cross-section is relatively uniform and the internal stress is small. Compared with ordinary I-beam steel, it has the advantages of large section modulus, light weight and metal saving, which can make buildings The structure is reduced by 30-40%; and because the inner and outer sides of the legs are parallel and the leg ends are at right angles, they can be assembled into components, which can save 25% of the welding and riveting workload. It is often used in large buildings (such as factories, high-rise buildings, etc.) that require large interception capacity and good cross-sectional stability, as well as bridges, ships, lifting and transportation machinery, equipment foundations, brackets, foundation piles, etc.

H-shaped steel is an economical cross-section steel that is optimized and developed from I-shaped steel with better cross-section mechanical properties. In particular, the cross-section is the same as the English letter "H", so it is named after it. Its characteristics are as follows:

◆ Wide flange and high lateral stiffness. Strong bending resistance, about 5%-10% better than I-beam.

◆ The two surfaces of the flange are parallel to each other, making connection, processing and installation easy.

◆ Compared with welded I-beam, it has low cost, high precision and small residual stress. It does not require expensive welding materials and weld inspection, saving about 30% of the cost of steel structure production.

◆ Under the same cross-sectional load. Hot-rolled H steel structure is 15%-20% lighter than traditional steel structure.

◆ Compared with concrete structures, hot-rolled H steel structures can increase the use area by 6%, while the structure's dead weight is reduced by 20% to 30%, reducing the internal stress of structural design.

◆ H-shaped steel can be processed into T-shaped steel, and honeycomb beams can be combined to form various cross-sectional forms, which greatly meets the needs of engineering design and production.

4. Analysis of characteristics of section steel

High structural strength: Compared with I-beam, the section modulus is large, and 10-15% of metal can be saved under the same load-bearing conditions.

Flexible and rich design styles: When the beam height is the same, the bays of the steel structure can be 50% larger than the bays of the concrete structure, making the building layout more flexible.

Light weight of the structure: It is lighter than the weight of the concrete structure. The reduction of the weight of the structure reduces the internal force of the structure design, which can make the foundation treatment requirements of the building structure lower, the construction is simple, and the cost is reduced.

High structural stability: The steel structure mainly made of hot-rolled H-shaped steel has a scientific and reasonable structure, good plasticity and flexibility, and high structural stability. It is suitable for building structures that can withstand large vibration and impact loads, and has strong resistance to natural disasters. It is especially suitable for some building structures in earthquake-prone areas. According to statistics, when a devastating earthquake of magnitude 7 or above occurs in the world, steel structure buildings dominated by H-shaped steel suffer the least damage.

Increase the effective use area of the structure: Compared with concrete structures, the cross-sectional area of steel structure columns is small, which can increase the effective use area of the building. Depending on the different forms of the building, the effective use area can be increased by 4-6%.

Save labor and materials: Compared with welding H-shaped steel, it can significantly save labor and materials, reduce the consumption of raw materials, energy and labor, have low residual stress, and have good appearance and surface quality.

Ease of machining: easy structural connection and installation, as well as easy removal and reuse.

Environmental protection: The use of H-shaped steel can effectively protect the environment, which is reflected in three aspects: first, compared with concrete, dry construction can be used, which produces less noise and less dust; second, due to the reduced weight, less soil is required for foundation construction , causing little damage to land resources, in addition to significantly reducing the amount of concrete and the amount of excavation, which is conducive to the protection of the ecological environment; thirdly, after the service life of the building structure expires, the amount of solid waste generated after the structure is dismantled is small, and scrap steel resources are recycled High value.

High degree of industrial production: The steel structure mainly made of hot-rolled H-shaped steel has a high degree of industrial production, which is convenient for mechanical manufacturing, intensive production, high precision, easy installation, and easy to ensure quality. It can be built as a real house manufacturing factory, bridge manufacturing factory, Industrial plants, manufacturing plants, etc. The development of steel structures has created and promoted the development of hundreds of emerging industries.

The project construction speed is fast: it occupies a small area, is suitable for all-weather construction, and is less affected by climate conditions. The construction speed of steel structures made of hot-rolled H-shaped steel is about 2-3 times that of concrete structures. The capital turnover rate is doubled, which reduces financial costs and thus saves investment.