Assembled building is the direct manifestation of assembling construction link in building industrialization. It is a building assembled on site from prefabricated parts produced by factories. The whole process should be standardized design, factory production, assembling construction, integrated decoration, information management and intelligent application. Assembled building is the direct manifestation of assembling construction link in building industrialization. It is a building assembled on site from prefabricated parts produced by factories. The whole process should be standardized design, factory production, assembling construction, integrated decoration, information management and intelligent application.

Assembled building has the advantages of stable quality, low energy consumption, low pollution, high production efficiency, low safety accidents, low labor intensity and good working conditions.

Question 1: Is there any guarantee for the quality and safety of assembled buildings? Is it solid?

In the process of design, through the simulation of various calculation models, diversified and omni-directional physical experiments, and through the practice of a large number of projects at home and abroad, it is proved that the quality and safety of houses can stand the test, and the technology is mature and reliable.

Because a large number of parts of assembly building are manufactured in factories, the quality control ability of assembly building is far greater than that of traditional cast-in-situ wet operation.


Question 2: Are assembled buildings precast by coagulation?

At present, there are three main modes of industrialized construction production in China:

Precast Concrete Assembly Building (PC Building)

The building is composed of prefabricated concrete members, assembled, connected and partly cast-in-place concrete structures.

Steel structure building

Steel structure as the main structure, combined with industrial floor and internal and external wall system, forms a complete building system. Its advantages are wide application range, light weight, energy saving and environmental protection.

Wood structure assembly building

Due to limited resources and environmental conditions, it is a long way to go to promote it nationwide.


Question 3: Can it resist earthquakes?

At present, the seismic performance of assembled building structures in China is basically the same as that of cast-in-place structures, even some of them exceed the seismic performance of cast-in-place structures, which can meet the requirements of Beijing seismic fortification of magnitude 8.

One of the key technologies for earthquake resistance is the connection technology of assembled joints.

At present, the main technology adopted in Beijing was born in the United States in 1970s and introduced to Japan in 72 years. The sleeve was prefabricated in the component, and the steel bar at the other end was connected by high-strength grouting material at the construction site.


Sleeve connection technology of steel bar grouting has been widely used in Japan and the United States in the last century, including stress-strain curve of sleeve and cyclic tension fatigue test. This technology has been tested for a long time and has been tested by strong earthquakes. Both the United States and Japan conclude that it can be used boldly in high-rise buildings.

In addition, the seismic performance of assembled buildings can be enhanced by introducing isolation measures.
   
 
Principle of shock absorption: When the earthquake comes, the flexible building starts to shake, and the energy generated will be absorbed by the shock absorber column to protect the key columns and beams from being destroyed.

Question 4: There used to be large slab houses. Why should we promote assembly buildings now?

In the 1980s, the focus of China's capital construction changed from production to life. In order to quickly solve the housing needs of the people, assembled large-scale building began to emerge and develop rapidly. Since the early 1990s, large-scale buildings have suddenly disappeared.

The reasons for this phenomenon are as follows.

Firstly, the market requires diversification of household types and individualization of decoration. The contradiction between design standardization and diversification can not be solved by the large plate structure system, which makes the production of factories more difficult and the cost more expensive.

Second, the large plate structure system failed to solve the waterproofing problem well, and a large number of seepage phenomena appeared around 15 years after its establishment.

Third, the rapid development of cast-in-place concrete construction technology (such as large formwork technology), migrant workers into the city, low labor costs, accelerating the demise of the slab structure system;

Fourthly, with the urgency of reducing population dividend and environmental pollution in China, the 18th National Congress put forward the requirement of "ecological civilization construction". The construction industry must take the industrialization road of saving resources and energy and reducing environmental pollution. Combining with domestic and foreign experience, the use of assembly building is one of the main means.


Question 5: What is the sound insulation effect?

The assembled building floor is a composite floor, which is different from the hollow floor in the past. It is based on the prefabricated floor to reproduce a layer of concrete floor, thus forming a solid assembled monolithic floor.

Lightweight concrete interior partition wall is usually made of lightweight slabs or concrete products, and its material itself has superior sound insulation performance. Its light steel keel partition wall usually adds sound insulation materials such as rock wool or insulation board in the middle, which meets the national standard in sound insulation standards.

In terms of sound insulation standard, it is not only consistent with cast-in-place floor, but also has good smoothness, saving formwork and convenient construction.

Question 6: The joints of assembly building are all bonded with glue. How to avoid frost heave, corrosion, rain and snow leakage and other problems?

At present, fabricated buildings solve the problem of water leakage through three ways: structural waterproofing, structural waterproofing and material waterproofing.

Structural waterproofing: vertical joint cast-in-situ concrete pouring, structure self-waterproofing.

Structural waterproofing: Horizontal seam anti-sill structure to prevent water from entering the room.

Material waterproofing: Exterior wall joints are waterproofed with "modified silicone gel".

Question 7: Is assembly building expensive?

Essentially, the construction technology of assembly and cast-in-place construction is quite different, the construction process is different, the organization and management methods are different, and the economic, social and environmental benefits are also different, so the "cost" between them should not be simply compared.

Generally speaking, the cost increase of assembled construction mainly includes: prefabricated component products and transportation costs, site installation and hoisting costs, large-scale machinery rental fees, wall and floor joint treatment and related material costs;

Cost reduction mainly includes: steel and concrete projects are carried out in prefabricated component factories, which reduces the cost of site masonry, plastering labor, and field support and formwork costs.

In addition, the current state vigorously promotes assembly building, will increase policy support to reduce the incremental cost of assembly building through area incentives, full decoration, technical training of industrial workers, reducing labor costs, increasing construction business and reducing construction costs.



Question 8: What is the status of assembly buildings abroad?

Europe

Europe is the origin of the modern industrial revolution, and it is no exception in the field of industrial production of residential buildings. Especially in the Nordic region, because of the cold climate and short construction period, labor costs are very high. As the earliest residential production and construction mode of "factory prefabrication and on-site assembly" in Europe, the prefabrication rate in Finland, Sweden, Norway and other countries is as high as 70%.


Japan

Seventy percent of Japanese urban residential buildings are single-door villas, most of them are light steel and wood structure systems. There are many high-rise residential buildings in big cities, most of them are "assembled frame structure system". The technical characteristics of this system are "assembled frame structure + external wall hanging board". Generally, the main body is constructed first, and then the hanging board is installed.


USA, Canada, Australia

In the United States, Canada and Australia, owing to the small population density, independent villas are the main types of common dwellings. In addition to the rich wood resources and the pursuit of individualization, concrete structures are seldom used. The structure system of villas is mostly light steel or wood structures. The required parts have been fully standardized and integrated, and can realize factory production, or even realize factory production. Households can buy all kinds of building materials needed in the supermarket, and they can complete the construction of their own houses.

Question 9: Is there a domestic market for fabricated buildings?

At present, most of the state government's affordable housing is constructed by assembled buildings, in terms of quality, housing scale, etc.

Huxing standardization has been greatly improved.

In addition to government-supported housing, commercial housing is also gradually expanding in the field of assembly building. According to the latest "Thirteenth Five-Year Plan of Action for Assembly Building", by 2020, the proportion of assembly building in new buildings will reach more than 15% in the whole country, with more than 20% in key areas, more than 15% in active areas and more than 10% in encouraged areas.


Establish and improve the policy system, planning system, standard system, technical system, product system and supervision system of assembly building, form a group of large-scale production enterprises and general contracting enterprises of assembly building design, construction and parts, form a professional team of assembly building, comprehensively improve the quality, benefit and quality of assembly building, and realize the all-round development of assembly building. 。

We believe that in the future assembly building will become a major domestic construction industry gospel.