High-quality structural form in construction: steel structure

Steel structureis a structure composed of Steel Materials and is one of the main types of building structures. The structure is mainly composed ofsteel beams, Steel Columns,steel trusses and other components made of section steel and steel plates, and adopts silanization, pure manganese phosphating, washing and drying, galvanizing and other rust removal and rust prevention processes. Welds, bolts or rivets are usually used to connect individual components or components. Because of its light weight and simple construction, it is widely used in large-scale factories, venues, super high-rise buildings, bridges and other fields. The steel structure is easy to corrode, and the general steel structure should be derusted, galvanized or painted, and it should be maintained regularly.

Steel is characterized by high strength, light weight, good overall stiffness, and strong resistance to deformation, so it is particularly suitable for building large-span and ultra-high, super-heavy buildings; The material has good homogeneity and isotropy, which is an ideal elastomer, which is most in line with the basic assumptions of general engineering mechanics. The material has good plasticity and toughness, can have large deformation, and can bear the dynamic load well; short construction period; It has a high degree of industrialization and can carry out specialized production with a high degree of mechanization.
The steel structure should be studied with high-strength steel to greatly improve its yield point strength; In addition, new varieties of steel should be rolled, such as H-shaped steel (also known as wide flange steel) and T-shaped steel and profiled steel plates to meet the needs of long-span structures and super high-rise buildings.
In addition, there is no thermal bridge light steel structure system, the building itself is not energy-saving, this technology solves the problem of cold and hot bridge of the building with ingenious special connectors; The small truss structure allows the cables and water pipes to pass through the wall, and the construction and decoration are convenient.
peculiarity
1. The material has high strength and light weight
Steel has high strength and high modulus of elasticity. Compared with concrete and wood, the ratio of its density to yield strength is relatively low, so the cross-section of the steel structure is small, the weight is light, it is convenient for transportation and installation, and it is suitable for the structure with large span, high height and heavy load.
2. The steel has good toughness, good plasticity, uniform material and high structural reliability
It is suitable for bearing impact and dynamic loads, and has good seismic performance. The internal structure of the steel is uniform, which is close to the isotropic homogeneous body. The actual working performance of the steel structure is more in line with the calculation theory. Therefore, the steel structure has high reliability.
3. The degree of mechanization of steel structure manufacturing and installation is high
The steel structure components are easy to manufacture in the factory and assemble on the construction site. The mechanized manufacturing of steel structure components in the factory has high precision, high production efficiency, fast assembly speed and short construction period. Steel structure is one of the most industrialized structures.
4. The sealing performance of the steel structure is good
Because the welded structure can be completely sealed, it can be made into high-pressure vessels, large oil pools, pressure pipelines, etc., which have good air tightness and water tightness.
5. The steel structure is heat-resistant or fire-resistant
When the temperature is below 150°C, the properties of the steel change very little. Therefore, the steel structure is suitable for the hot workshop, but when the surface of the structure is exposed to thermal radiation of about 150 °C, it should be protected by a heat insulation board. The temperature is between 300°C and 400°C. The strength and elastic modulus of steel are significantly reduced, and the strength of steel tends to zero when the temperature is about 600°C. In buildings with special fire protection needs, the steel structure must be protected with refractory materials to improve the fire resistance level.
6. The corrosion resistance of the steel structure is poor
Especially in the environment of humid and corrosive media, it is easy to rust. Generally, the steel structure should be derusted, galvanized or painted, and it should be maintained regularly. For offshore platform structures in seawater, special measures such as "zinc block anode protection" are required to prevent corrosion.
7. Low carbon, energy saving, green and environmentally friendly, reusable
The demolition of steel structure buildings will hardly produce construction waste, and steel can be recycled and reused.

1. The upstream industry of steel structure is the supply of raw materials such as steel
The steel industry is the material basis for the development of the steel structure industry, and the technological progress of the steel industry has created favorable conditions for the application of steel structure. Some large enterprises in the domestic iron and steel industry have begun the research and development of steel varieties and technologies for building structures, and have successively developed high-strength steel and refractory, weather-resistant, seawater-resistant, layer-resistant tear-resistant, low-temperature resistant steel, as well as H-shaped steel, high-performance color-coated steel plate, cold-formed steel, etc., which have laid a good application foundation for the development of steel structure industry.
2. The impact of upstream and downstream on the industry
The upstream of the steel structure is mainly the steel industry, and the price fluctuations of steel products directly affect the procurement cost of the industry. On the whole, the upstream industry is basically a competitive industry, producing various types of steel plates, steel pipes, section steel and other steel used in steel structures, among which H-beam and medium and heavy plate are the most commonly used products in steel structure buildings. According to industry insight research data, the crude steel output in 2011 reached 696 million tons, and the output is relatively saturated, and the raw materials required for the production of steel structures can obtain a stable supply.
The downstream industry has a greater traction and driving role in the development of the steel structure industry, and their demand changes directly determine the future development of the industry. With its comprehensive advantages of high strength, light weight, good seismic performance, high degree of industrialization, short construction period, strong plasticity, energy conservation and environmental protection, steel structure has been widely used in industrial plants, municipal infrastructure construction, cultural, educational and sports construction, electric power, bridges, offshore oil engineering, aerospace and other industries, and the market space has gradually expanded. In addition, once the residential steel structure market makes a breakthrough and gradually replaces the traditional building form into the field of residential construction, the steel structure industry will attract explosive growth.

roofing system
It is composed of roof truss, structural OSB panel, waterproof layer, light roof tile (metal or asphalt shingle) and related connectors. The appearance of the light steel structure roof of Maite Building can be combined in a variety of ways. There are also a variety of materials. On the premise of ensuring the waterproof technology, there are many options for the appearance.
wall structure
The wall of the light steel structure residential building is mainly composed of wall frame columns, wall top beams, wall bottom beams, wall supports, wall panels and connectors. The building light steel structure residential generally takes the inner transverse wall as the load-bearing wall of the structure, the wall column is a C-shaped light steel member, and its wall thickness is determined according to the load, usually 0.84~2 mm, and the spacing between the wall columns is generally 400~600 mm.

Thermal insulation and energy-saving technologyIn order to ensure the thermal insulation effect, the thermal insulation materials used in the exterior walls and roofs of buildings can be used for a long time and can be insulated. In addition to filling the glass fiber mesh cloth between the wall columns of the wall, the building light steel structure house generally pastes a layer of insulation material on the outside of the wall, which effectively separates the thermal bridge from the wall column to the exterior wall panel; The joists between the floors are filled with fiberglass to reduce heat transfer through the floors; All interior walls are filled with fiberglass between the columns to reduce heat transfer between the walls.
One of the most critical issues of light steel structure in fire protection technology is the application of fire protection technology, and the fire resistance level of light steel structure housing is level four. The building light steel structure house is pasted with fireproof gypsum board on both sides of the wall and the ceiling of the floor, and the 25.4 mm thick (1 inch) gypsum board is used to protect the ordinary firewall and the household wall to meet the fire prevention requirements of 1 hour.
The light steel structure of sound insulation technology is filled with glass wool between the interior and exterior walls and floor joists, which effectively prevents the audio part transmitted through the air, and the impact sound transmitted through the solid is treated as follows: for the sub-household wall, two wall columns are used to form a second wall with an intermediate gap; For the small keel of the fixed gypsum board for the ceiling, the elastic structure with small grooves is used to effectively reduce the solid sound propagation between floors.

The steel structure will be subjected to various forms of action (load, uneven settlement of the foundation, temperature, etc.) in the process of use, so the steel should have good mechanical properties (strength, plasticity, toughness) and processing performance (cold and hot processing and welding performance) to ensure the safety and reliability of the structure. There are many types of steel, and only a few meet the requirements of steel structure, such as Q235 in carbon steel, l6Mn in low-alloy steel, 20 manganese vanadium steel (20MnV) for high-strength bolts, etc. Performance index 1, strength steel strength index by elastic limit σe, yield limit σy, and tensile limit σu, design based on the yield strength of steel, high yield strength can reduce the weight of the structure, save steel, reduce the cost. The tensile strength σu is the maximum stress that the steel can withstand before failure, and the structure at this time loses its performance due to great plastic deformation, but the structural deformation is large but not collapsed, which meets the requirements of the structure to resist rare earthquakes. The magnitude of the σu/σy value can be regarded as a parameter of the strength reserve of the steel. 2. Plasticity The plasticity of steel generally refers to the property that after the stress exceeds the yield point, it has significant plastic deformation without breaking. The main indicators to measure the plastic deformation ability of steel are elongation δ and section shrinkage ψ. 3. Cold bending performance The cold bending performance of steel is a measure of the resistance of steel to cracks when it is bent at room temperature to produce plastic deformation. The cold bending performance of steel is to use cold bending test to test the bending deformation performance of steel to withstand a specified degree of bending. 4. Impact toughness The impact toughness of steel refers to the ability of steel to absorb mechanical kinetic energy during fracture under impact load, and is a mechanical property that measures the resistance of steel to impact load, which may lead to brittle fracture due to low temperature and stress concentration. Generally, the impact toughness index of steel is obtained through the impact test of standard specimens. 5. Welding performance The welding performance of steel refers to the welding joint with good performance under the condition of a certain welding process. Welding performance can be divided into two types: welding performance in the welding process and welding performance in use performance. The welding performance in the welding process refers to the sensitivity of the weld and the metal near the weld during the welding process without thermal cracks or cooling without cooling shrinkage cracks. Good welding performance means that under certain welding process conditions, the weld metal and the nearby base metal will not produce cracks. The welding performance in terms of use performance refers to the impact toughness of the weld and the ductility of the heat-affected zone, and the mechanical properties of the weld and the heat-affected zone steel are required to be not lower than the mechanical properties of the base metal. China adopts the welding performance test method of the welding process, and also adopts the welding performance test method in the nature of use. 6. Durability There are many factors that affect the durability of steel. First of all, the corrosion resistance of steel is poor, and protective measures must be taken to prevent steel from corroding and rusting. Protective measures include: regular maintenance of steel paint, the use of galvanized steel, in the presence of acid, alkali, salt and other strong corrosive media, the use of special protective measures, such as the offshore platform structure using "anodic protection" measures to prevent jacket corrosion, fixed on the jacket zinc ingot, seawater electrolyte will automatically corrode the zinc ingot.