H-section steel is a kind of economic section high-efficiency profile with more optimized section area distribution and more reasonable strength weight ratio. It is named because its section is the same as the English letter \"H\". Because all parts of H-section steel are arranged at right angles, H-section steel has the advantages of strong bending resistance, simple construction, cost saving and light structural weight in all directions, and has been widely used.
The section shape is similar to the capital Latin letter h. It is also called universal steel beam, wide edge (edge) I-beam or parallel flange I-beam. The cross section of H-section steel usually includes web and flange plate, also known as waist and edge.
The inner and outer sides of the flange of H-shaped steel are parallel or nearly parallel, and the end of the flange is at right angles, so it is named parallel flange I-steel. The web thickness of H-beam is smaller than that of ordinary I-beam with the same height of web, and the flange width is larger than that of ordinary I-beam with the same height of web, so it is also named wide edge I-beam. Determined by the shape, the section modulus, moment of inertia and corresponding strength of H-beam are obviously better than those of ordinary I-beam with the same single weight. When used in metal structures with different requirements, it shows its superior performance in terms of bearing bending moment, pressure load and eccentric load. Compared with ordinary I-beam, it can greatly improve the bearing capacity and save metal by 10% ~ 40%. H-shaped steel has wide flange, thin web, many specifications and flexible use. It can save 15% ~ 20% metal in various truss structures. Because the inner and outer sides of the flange are parallel and the edge end is at right angles, it is easy to assemble and assemble into various components, which can save about 25% of the welding and riveting workload, greatly accelerate the construction speed of the project and shorten the construction period.
Due to the above advantages, H-section steel is widely used in: various civil and industrial building structures; Various large-span industrial plants and modern high-rise buildings, especially in areas with frequent seismic activities and under high-temperature working conditions; Large bridges with large bearing capacity, good section stability and large span are required; Heavy equipment; Expressway; Ship skeleton; Mine support; Foundation treatment and embankment works; Various machine components.
There are many product specifications of H-beam, and the classification methods are as follows. (1) According to the flange width of the product, it is divided into wide flange, middle flange and narrow flange H-shaped steel. The flange width b of wide flange and middle flange H-shaped steel is greater than or equal to the web height H. The flange width b of narrow flange H-shaped steel is about half of the web height H. (2) It can be divided into H-shaped steel beam, H-shaped steel column, H-shaped steel pile and H-shaped steel beam with extremely thick flange according to product use. Sometimes, parallel leg channel steel and parallel flange T-shaped steel are also included in the scope of H-shaped steel. Generally, narrow flange H-section steel is used as beam material and wide flange H-section steel is used as column material. Therefore, it is also known as beam H-section steel and column H-section steel. (3) According to the production mode, it is divided into welded H-section steel and rolled H-section steel. (4) It is divided into large, medium and small H-shaped steel according to size. Generally, products with a web height h of more than 700mm are called large, those with a web height of 300 ~ 700mm are called medium, and those with a web height of less than 300mm are called small. By the end of 1990, the web height of the world\'s largest H-shaped steel was 1200mm, and the flange width was 530mm.
Internationally, the product standards of H-beam are divided into British system and metric system. The United States, Britain and other countries adopt the British system, while China, Japan, Germany and Russia adopt the metric system. Although the measurement units used in the British system and the metric system are different, most of the H-section steels use four dimensions to express their specifications, namely: web height h, flange width b, web thickness D and flange thickness t. Although there are different ways to express the size of H-beam in the world. However, the size range and dimensional tolerance of the products produced have little difference.