Analysis! The most comprehensive steel structure knowledge...

https://www.tpasteel.com/steel-structure-garage.html

1. What is steel structure?

What is a steel structure? In academic language, a steel structure is a structure mainly made of stainless steel. It is one of the main types of building structures today. The characteristics of stainless steel plates are high strength, light weight, good overall rigidity and strong deformation ability, so they are especially suitable for building large-span and extremely tall and heavy buildings. Steel structure is a structure made of steel columns, steel columns, steel pipe trusses and other components made of channel steel and thick steel plates; each component or component is connected by welding, anchor bolts or rivets.

2. Steel structure characteristics

1. Stainless steel plates have good ductility, good plastic deformation, well-proportioned materials, high structural reliability, are suitable for bearing impact driving loads, and have excellent seismic performance. The internal structure of the stainless steel plate is well-proportioned and tends to be anisotropic and uniform. The actual working performance of the steel structure is more in line with the calculation theory. Therefore, the steel structure has high reliability.

2. The raw material has high compressive strength, is light in weight, has high bolt strength, and has high elasticity. Compared with concrete and wood, the ratio of its density to tensile strength is relatively low. Therefore, under the same bearing capacity standard, the steel structure has a small cross-section and light weight, which is convenient for transportation and installation, and is suitable for spans. A large, high-height, heavy-bearing structure.

3. The steel structure has good sealing performance, because the electric welded structure can ensure complete sealing and can be made into pressure vessels with very good sealing and tightness, large and medium-sized oil pools, Class II pressure vessels, etc.

4. The steel structure is resistant to high temperatures but not fireproof. When the temperature is below 150°C, the properties of the stainless steel plate will not change much. Therefore, the steel structure is suitable for thermal production workshops, but when the surface of the structure is exposed to heat radiation of about 150°C, it must be protected by insulating materials. When the temperature is between 300℃ and 400℃, the bolt strength and elastic mold are significantly reduced. When the temperature is around 600℃, the compressive strength of the stainless steel plate tends to zero. In engineering buildings with unique fire safety requirements, the steel structure must be maintained with fire-resistant insulation materials to improve the fire protection level.

5. Steel structures have poor corrosion resistance, and are very prone to rust, especially in humid and corrosive environments. Generally, steel structures require anti-rust treatment, hot-dip galvanizing or architectural coatings, and must be maintained. For deep-sea service platform structures located on the sea surface, unique measures such as "zinc block anode protection" need to be adopted to provide corrosion resistance.

6. Steel structure manufacturing and installation machinery has a high level of automation, and steel structure components are helpful for manufacturing in factories and assembling at construction sites. Mechanical automation in processing plants produces steel structural components with high precision and productivity, faster assembly at construction sites, and tight construction schedules. Steel structure is the most modern structure.

3. Development trend and history of steel structures

In the early days of our country, there were extraordinary achievements in iron structures. However, due to the constraints of feudal society and the lack of scientific research, our country has been stuck at the level of iron buildings for more than 2,000 years. It was not until the end of the 19th century that intelligent steel structures began to be used in my country. After the founding of New China, the application of steel structures has a very large development trend, both in quantity and quality, far exceeding the past. After 2000, my country's social economy has improved significantly, its overall national strength has increased significantly, and China's steel output has become a world power. Around 2008, driven by the Summer Olympics, a steel structure construction trend emerged. Strong market demand promoted the rapid development of steel structure construction, and a large number of steel structure exhibition halls, airports, subway stations and many other projects were completed. Among them, some steel structure buildings have world-class standards in manufacturing and installation technology, such as the Bird's Nest Stadium for the Summer Olympics and other buildings. We have reached a high level in technical aspects such as design, manufacturing and installation, and have mastered the design and construction techniques of various complex buildings.

4. Main features of steel structure

Wind resistance

The steel structure engineering building has light weight, high compressive strength, good overall stiffness and strong deformation ability. The building itself weighs only one-fifth of the brick-concrete structure and can withstand a storm of 70 meters per second, allowing life assets to be reasonably maintained.

Durability

Most of the flat roofs of low-rise villas are pitched roofs, so most of the flat roof structures use a triangular steel roof truss system made of cold-drawn steel components. The light steel structural components are sealed with structural panels and plaster. After the slab, a very strong "slab-rib structural system" was formed. This structural system has stronger seismic resistance and the ability to withstand horizontal loads, and is suitable for areas with a seismic resistance level of 9 degrees or above.

Thermal insulation

The sound insulation and noise reduction effect is an important indicator for evaluating housing. The windows installed in the light steel structure system are all made of hollow glass windows. The sound insulation and noise reduction effect is very good, with the sound insulation and noise reduction reaching more than 40 decibels; it is separated by light steel keels. The sound insulation and noise reduction effect of the wall made of gypsum board and thermal insulation material can reach 60 decibels.

Thermal insulation

The thermal insulation material used is mainly fiberglass wool, which has excellent thermal insulation effect. Thermal insulation panels used for walls can effectively prevent the "thermal bridge" phenomenon on the wall and achieve better thermal insulation effects. The thermal resistance value of R15 insulation material with a thickness of about 100 mm can be equivalent to that of a 1-meter-thick wall.

physical and mental health

Do-it-yourself construction reduces the environmental pollution caused by waste. 100% of the steel structure materials of the house can be recycled, and most of the other supporting facilities materials can also be recycled, which is in line with the current environmental protection concept; all materials are green buildings and consider the ecological environment. Protective regulations are beneficial to physical and mental health.

Usage performance

The light steel structure housing structure is entirely composed of cold-drawn thick-walled steel components. The anchors are made of very anti-corrosion and high-strength cold-rolled galvanized steel to effectively prevent the risk of rusting of the steel during the construction and use process. , extending the service life of light steel structural components. The structural service life reaches 100 years.

comfort

The light steel structure wall adopts a high-efficiency environmental protection and energy-saving system, which has a suction function and can adjust the indoor air quality and dryness; the roof has a natural ventilation function, which can create a flowing air space in the air inside the house to ensure the indoor air quality. Natural ventilation and heat dissipation requirements.

5. Advantages and Disadvantages of Steel Structure

advantage

1. Steel structure buildings can better meet the requirements for flexible separation of depth in the building than traditional Chinese buildings, and can increase area utilization by reducing the cross-sectional area of columns and using lightweight partitions, indoors The area of rational use increased by about 6%.

2. The environmental protection and energy-saving effect is very good. The walls are made of lightweight environmentally friendly and energy-saving standardized C-shaped steel, square steel pipes, and color steel sandwich panels. They have good thermal insulation performance and good earthquake resistance. Environmental protection and energy saving 50%,

3. Applying the steel structure system to residential buildings can make full use of the steel structure's good ductility, strong plastic deformation ability, and high-quality earthquake resistance and impact resistance, further improving the safety and reliability of housing. Especially in the case of earthquake disasters and strong typhoons, steel structures can prevent building collapse and damage.

4. The total weight of the building is light. The steel structure housing system itself is light, about half that of the concrete structure, which can greatly reduce the construction cost.

5. The construction speed is faster, the construction period is at least one-third shorter than the traditional housing management system, and a 1,000-square-meter building can be completed in only 20 days and five workers.

6. The environmental protection effect is very good. The use of sand, stone and ash is greatly reduced during the construction of steel structure housing projects. The commonly used raw materials are mainly green, 100% recycled or dissolved raw materials. During the building demolition, most of the raw materials can be replaced or dissolved, and no Can easily lead to waste.

7. With flexibility and abundance. With a large depth design, the space can be divided into multiple plans to meet the different needs of users.

8. Comply with the requirements of construction industrialization and sustainable development. The steel structure is suitable for mass production in processing plants, has a high level of modernization, and can integrate environmental protection, energy saving, moisture-proof, heat insulation, windows and doors and other advanced finished products. The use of complete sets of equipment integrates design, production and manufacturing, and engineering construction. , to improve the level of the infrastructure industry chain.

shortcoming

1. Diversity

The diversity of construction quality problems in steel structure building projects is reflected in the variety of factors that cause product quality problems, and the causes of product quality problems are also complex. Even for product quality problems with the same characteristics, the causes are sometimes different, and thus The analysis, identification and resolution of product quality problems increase diversity. For example, electric welding gaps can occur in the welding metal or in the thermal damage of butt welds, either on the welding surface or inside the welding; the gap direction can be parallel to the welding seam or parallel to the welding seam. The weld seam can be bisected vertically, and the seam may be either a cold seam or a hot seam; the cause is also caused by poor use of welding materials and poor heating or post-heating of electric welding.

2. Plasticity

The quality problems of steel structure building construction products will continue to develop and change with the increase of external changes and time, and quality defects will slowly be reflected. For example, due to the change of ground stress in the welding of steel components, gaps were formed in the welding that originally had no gaps: as a result of the hydrogen movement in the welding after welding, delayed gaps can be formed. If the component bears a load for a long time, the steel component will cause the lower arch to bend and deform, causing safety hazards.

3. Serious consequences

The serious consequences of construction quality problems in steel structure construction projects are mainly as follows: Generally, it affects the smooth progress of the project construction, resulting in delays in the construction period and increased costs; more seriously, building collapse leads to personal casualties, asset damage, and poor results. social influence.

4. High incidence

Because modern buildings in China are all dominated by concrete structures, managers and technicians engaged in construction are relatively unfamiliar with the fabrication and construction techniques of steel structures, and the actual construction team led by migrant workers is even more unfamiliar. Failure to understand the scientific construction methods of steel structure projects often leads to safety accidents during the construction process.

6. The development future of steel structures

my country's steel structure industry has developed rapidly in the past 10 years and has become a steel structure powerhouse with the largest usage of steel structures, the strongest manufacturing and construction capabilities, the largest industrial scale, and the largest company in the world. .

Steel structure companies: We must attach great importance to the development trend of the "Twelfth Five-Year Plan"

The successful construction of major steel structure projects across the country shows that my country's steel structure comprehensive technical strength is at an internationally advanced level. However, my country's steel structure industry chain is also very different from that of capitalist countries in terms of information management, automation, standardization, and scientific research innovation. 2011 is the beginning and end of my country's "Twelfth Five-Year Plan". Relevant laws and regulations, ministries, industry associations, group companies, and steel structure companies will conduct investigations and analyze the sales market and future development trends. The National Development and Reform Commission, the Ministry of Industry and Information Technology, and the Ministry of Science and Technology have also studied the definition and planning goals of relevant strategic emerging industries, and focused on industrial chains that have international standards, strong scientific and technological innovation capabilities, strong economic globalization capabilities, and can capture a large number of markets. , will be incorporated into the overall plan and given support and policy support. Opportunities are also challenges. Whether my country's steel structure industry chain can move up the ladder and scale, the development trend during the "Twelfth Five-Year Plan" period is particularly important.

After investigation and analysis, and after soliciting the opinions and suggestions of relevant authoritative experts, the China Steel Structure Research Association formulated the "Draft of Strategic Thoughts and Suggestions on the Steel Structure Industry in the National "Twelfth Five-Year Plan"". After soliciting suggestions from relevant staff , the research institute will implement and improve the relevant authoritative experts of the organization to promote higher development trends in the steel structure field during the "Twelfth Five-Year Plan" period.

Due to its economic and technical advantages, low-carbon environmental protection, energy conservation and emission reduction, green economy and modernization, and industrial development trends, the steel structure field can better integrate and meet the current needs of China's social and economic construction and will also become It has become one of the new industries with a broad market, numerous companies, continuous innovation, and full of vitality.