At present, the development of steel structure housing in China has entered an accelerated stage, and relevant industrial policies, standards and norms have been introduced one after another. Domestic steel production is sufficient, which provides a good development environment, material basis and technical conditions for the development of steel structure residential buildings. The following is my research paper on the structural system of steel residential buildings, which I compiled for you. I hope it will help you.
Firstly, this paper studies the development status of steel structure residence at home and abroad, introduces the characteristics and structural forms of steel structure residence, analyzes the technical problems existing in steel structure residence, and looks forward to the development prospect of steel structure residence industrialization in China.
Key words: steel structure residence; Advantages; Structural system; Application prospect
Since the reform and opening up, China's economy has developed continuously and rapidly, and the construction industry has also developed unprecedentedly, gradually becoming a pillar industry of the national economy. As a new type of green building system, steel structure residence is developing healthily and rapidly with the substantial increase of steel production and the continuous introduction of new materials and technologies.
1, development of steel structure residence at home and abroad
In many industrialized countries, such as the United States, Japan, Britain and Australia, the development and application of steel structure buildings have a history of several decades. The proportion of steel residential buildings in the United States has increased from 5% in the 1990s to more than 25% now, and steel buildings in Japan and Australia account for more than 50% of all buildings.
For a long time, due to the shortage of steel, the application of building steel structure in China has been limited. 11996, China steel output exceeded1100,000 tons, in 2002 it reached1900,000 tons, and in 2005 it reached 370 million tons, which has exceeded the total steel output of the United States, Japan, Russia and South Korea. The national steel policy changed from restricting the use of steel in 1950s and 1960s to saving steel in 1970s and 1980s, and then to encouraging the use of steel in 2 1 century, which provided excellent conditions for the development of building steel structures in China. At present, pilot projects of low-rise and high-rise steel structures have been carried out in Beijing, Tianjin, Shanghai, Laiwu, Shandong, Maanshan, Anhui, Guangzhou and Shenzhen, and 3 million to 5 million square meters of houses have been built.
2. Advantages of steel structure residence
Steel structure residence is the most potential environmental protection and energy-saving residence at present, which has broken through China? Qin brick hanwa? The traditional "X" building mode has replaced the traditional red brick and concrete, and it uses industrialized building materials completely, which has many advantages. It is an ideal building for human living environment in 2 1 century.
2. 1 steel structure has light weight, high strength and good seismic performance.
Steel structure materials have high strength, good plasticity and toughness, and good structural ductility. The weight of steel structure residence is about 1/3 ~ 1/2 of reinforced concrete residence. The reduction of self-weight reduces the effect of earthquake action, generally reducing the self-weight by half, which is equivalent to reducing the seismic fortification intensity by one degree, and the earthquake action can be reduced by 30% ~ 40%.
2.2 A high degree of industrialization, easy to achieve residential industrialization.
With the help of professional design software, the design cycle of steel structure residence is greatly shortened and the design standardization is realized. All parts are manufactured in the factory, with high precision and easy quality assurance. Easy to realize mechanized assembly, fast construction speed and short construction period. Compared with traditional houses, the construction period is shortened by more than 40%.
2.3 The space utilization rate is high, and the functional intervals are arranged reasonably.
Due to the characteristics of light weight and high strength of steel, it is convenient to form a large-column-spacing and large-bay house. However, traditional structures (such as brick-concrete structures and concrete structures) limit the free layout of space due to material characteristics. Excessive span and bay will lead to slab thickness, beam height and column size. Fat beam? Phenomenon, not only affects the appearance, but also increases the weight and cost. In terms of space utilization, the cross-sectional area of steel beams and columns used in steel structure residence is smaller than that of traditional structure, and the clearance area is also reduced, which makes the room use area increase, and the effective area can be increased by about 10% compared with traditional structure.
2.4 Environmental protection, energy saving and land saving.
At present, the residential system in China is mostly brick-concrete structure, and portland cement is widely used. After the disintegration of buildings, a large amount of construction waste is produced, which causes great damage to the environment. The solid clay brick used in masonry structure wastes a lot of land resources. The materials used in steel structure residence are mainly environmentally friendly and recyclable materials. After the building is demolished, the steel can be recycled 100%.
2.5 The steel structure residence has outstanding thermal insulation and sound insulation effect, beautiful appearance and rich structure.
Most of them use new lightweight wall enclosure materials, which are not easy to mildew and moth-eaten, and have obvious advantages over traditional houses in terms of heat preservation and sound insulation. The material of steel structure is light and high strength, and the structural design can create artistic architectural modeling and meet the requirements of residents for different architectural styles.
3. Structural system of steel structure residence
The structural system of steel structure residence is mainly composed of load-bearing structure system, supporting system, enclosure structure system and floor structure system.
3. 1 There are many combinations of load-bearing and supporting systems for steel structures. The main structures used in houses are steel frame structure system, steel supporting frame system, steel frame-shear truss structure system and staggered truss structure system.
Steel frame system is a typical flexible structural system, with simple structure, clear force, flexible plane layout, uniform structural stiffness, good seismic performance and poor lateral stiffness. Steel braced frame structure system usually adopts channel steel or angle steel to arrange vertical bracing system in the wall plane, which can effectively resist horizontal load, improve lateral stiffness and reduce story displacement. The members of the bearing system of steel structure residence generally adopt hot-rolled or high-frequency welded H-beam, hot-rolled or welded I-beam, square steel tube, round steel tube or cold-formed thin-walled steel.
3.2 The envelope system accounts for about 30% of the total cost of steel structure residence. In order to reduce the weight of the structure and meet the requirements of building energy saving, most of the retaining walls are made of light materials.
Autoclaved lightweight aerated concrete slab (ALC slab), SRC composite insulation wallboard, steel wire mesh composite insulation board, cement particleboard, etc. Can be used for external walls, light steel keel gypsum board, ALC lightweight board, sandwich composite board, straw board and so on. Can be used for interior walls.
3.3 The floor structure consists of steel beams and floors.
The floor system should ensure sufficient strength, stiffness and stability, and at the same time try to reduce the weight of the floor. The main types of floor slab are profiled steel plate and cast-in-place concrete composite floor slab and precast lightweight concrete slab.
4. Technical problems existing in steel structure residence.
4. 1 Fire Prevention
Steel structure has many advantages, but it also has its fatal defect, that is, poor fire resistance, and the bearing capacity and balance stability of steel will be greatly reduced with the increase of temperature. When the temperature reaches 400℃, the yield strength of steel is reduced to half of that at room temperature, and when the temperature reaches 600℃, steel basically loses all its strength and stiffness. There are two ways to solve this problem. One is to use fire-resistant weathering steel, that is, to add alloying elements (such as copper, nickel, chromium, silicon, phosphorus, etc.). ) to change the metallographic structure of steel, thus improving the inherent fire resistance and weather resistance of steel. At 600℃, the yield strength of the steel is not greater than1/3; The second is to use fire retardant coatings, foamed fire retardant coatings and outsourcing fire retardant layers. Most exposed steel members are coated with 10 ~ 40 ㎜, and the fire resistance can reach1.5 ~ 3h; For hidden steel members, perlite fire or fire prevention board is an economical and effective method.
4.2 Anti-corrosion problems
The corrosion of steel structure is directly related to environment, temperature and humidity. According to the test data at home and abroad, the corrosion rate of unprotected steel in the atmosphere in the first year is about twice that in the fifth year, and the corrosion rate outdoors is about four times that indoors. Steel hardly rusts in a dry environment. Therefore, exposed steel members are generally coated with anticorrosive paint or coating, or galvanized.
4.3 Standards and specifications
Because the development of steel structure residence in China is only ten years, the technical system of steel structure residence is not mature enough, the standards and specifications of steel structure residence are scattered and unsystematic, the technical level is uneven, and the degree of industrialization is not high, which needs further research, innovation and standardization.
5. The development prospect of steel structure residence in China.
At present, the production efficiency of domestic construction industry is low, and it is still a labor-intensive industry, while steel structure residence belongs to a high-tech and high-efficiency industry. Accelerating the research of steel structure residence will promote the transformation of construction industry into technology-intensive industry, and also promote the development of building materials, metallurgy, machinery, especially steel enterprises.
China steel structure association's 2009-20 12 steel structure industry situation, operation and development trend forecast report points out that? Energy saving and emission reduction? It is still an important task of China's economic development and the basic national policy of sustainable development, so the steel structure with energy saving, environmental protection and green advantages is favored by the market. According to the Steel Structure Industry formulated earlier by China Steel Structure Association? Eleventh five-year plan? The development planning proposal shows that the output of steel structure will reach 26 million tons in 20 10. According to the data currently available, it is predicted that the manufacturing capacity of China's steel structure industry will reach 30-40 million tons in 20 10, indicating that China's steel structure industry has a large development space.
6. Conclusion
At present, the development of steel structure housing in China has entered an accelerated stage, and relevant industrial policies, standards and norms have been introduced one after another. Domestic steel production is sufficient, which provides a good development environment, material basis and technical conditions for the development of steel structure residential buildings. We should constantly improve our research and development capabilities, master advanced foreign technologies, and promote the industrialization of steel residential buildings. I believe that the development prospect of steel structure residence in China is broad.
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