by Summary: prefabricated buildings are buildings assembled on the construction site with prefabricated parts and components.
The development of prefabricated buildings is a major change in China’s construction mode.
It is an important task to promote the development of prefabricated buildings to guide the rational layout of the production enterprises of parts and components in the construction industry.
This paper introduces the domestic and international investigation of precast concrete component factories, puts forward the key areas for the development of prefabricated buildings and the planning and layout of precast concrete component factories in China, studies and establishes the prediction and calculation model of the annual market demand of precast concrete components in the target areas (cities) and the model of typical precast component factories, as well as the suggestions for the planning and layout of precast component factories in the three urban clusters of Beijing Tianjin Hebei, Yangtze River Delta and Pearl River Delta.
Key words: prefabricated building; Precast concrete component factory; Planning Layout 1 research status and trends at home and abroad 1.1 research status and trends abroad prefabricated concrete structure buildings in developed countries have experienced decades of development.
At present, the technology has been very mature, and a relatively complete technical standard system and policy system have been formed.
The market in the field of housing construction is very stable.
As a prefabricated concrete component factory (hereinafter referred to as prefabricated component factory), foreign countries have already completed the planning layout and planning construction according to the market requirements.
In the 1980s, on the basis of fully considering urban development planning, local resource utilization, division of labor and cooperation between our factory and other professional factories, we conducted detailed analysis and in-depth certification on the nature and positioning of the factory, production scale, investment benefits, construction period, product supply scope and final economic benefits, and sought to form a production system with complete product types within a reasonable range of one region and one city, Coordinate the production and supply of various building components.
With the increasing emphasis on environmental protection in various countries, corresponding requirements are put forward for green production of prefabricated component plants, and strict measures are required to deal with sewage, noise, dust and other harmful substances.
The transportation of raw materials and finished products supply is also the key consideration of the prefabricated component factory.
The supply radius, transportation tools and traffic conditions of prefabricated components shall be carefully considered, and the reasonable proportion of component freight and total project cost shall be controlled to save the transportation cost as much as possible.
At present, the prefabricated component industry in developed countries is in a stable development period, the supply and demand of the construction industrialization market is balanced, the construction of new plants is very few, and the prefabricated component factory can operate stably for a long time.
1.2 domestic research status and development trend China’s construction industrialization and housing industrialization are accompanied by the synchronous development of national construction, and the development of different fields in different periods is obviously unbalanced.
At present, China is continuously promoting technological innovation and product upgrading, comprehensively spreading and deepening construction industrialization and housing industrialization throughout the country, and continuing to take the road suitable for the industrialization of new buildings.
In recent years, although the construction of prefabricated component plants in various parts of the country has a tendency of blooming everywhere, most of them are driven by the construction industrialization policy and are keen to invest for the purpose of seizing the commanding height of the industry.
Some places have already seen adverse situations such as intensified competition, overcapacity and waste of resources.
There is no national planning and layout of prefabricated component plants as guidance and control reference.
The next 10 years in China will be a golden period for the rapid development and finalization of building industrialization.
During this period, the planning and layout of prefabricated factories across the country will be supported by scientific and technological achievements urgently needed for in-depth research, so as to achieve overall planning, scientific layout, optimization of environment and resource allocation, transformation and upgrading of prefabricated component factories, promote scientific and technological progress and environmental friendliness of prefabricated component industry, and vigorously promote the development of building industrialization in China.
2.
Selection of key areas: according to the requirements of national macro policies, the development areas of prefabricated buildings in China are divided into three major urban agglomerations: Beijing Tianjin Hebei, Yangtze River Delta and Pearl River Delta.
Other cities with a resident population of more than 3 million are actively promoted, and other cities are encouraged to promote; Each region shall develop prefabricated concrete structure, steel structure and modern wood structure according to local conditions.
By 2020, China’s prefabricated buildings will account for more than 15% of the new buildings, of which the prefabricated buildings in the key promotion areas will account for more than 20% of the new building area, the actively promoted areas will account for more than 15%, and the encouraged areas will account for more than 10%.
By 2025, China’s prefabricated buildings will account for more than 30% of the newly built buildings, among which the prefabricated buildings in key promotion areas will account for more than 40% of the newly built building area, those in active promotion areas will account for more than 30%, and those in encouraged promotion areas will account for more than 20%.
For the selection of key areas, the research group has selected the urban agglomerations and key cities with good economic conditions, closely related economic development and demonstration effect in the key and actively promoting the development of prefabricated buildings, as shown in Fig.
1.
(1) urban agglomeration selection: Beijing Tianjin Hebei (Beijing, Tianjin, xiong’an), Yangtze River Delta (Shanghai, Suzhou, Wuxi), Pearl River Delta (Guangzhou, Shenzhen, Dongguan); (2) selection of key cities: East China (Nanjing, Hangzhou and Jinan), central China (Changsha, Wuhan and Zhengzhou), Southwest China (Chengdu and Chongqing).
Northeast (Shenyang) and Northwest (Xi’an).
3.
Dynamic prediction and calculation model of annual demand for components: the annual demand for prefabricated components in the target area and the city needs to be matched with the capacity of prefabricated component factories.
The accurate predicted value of annual demand is the key parameter of the layout of prefabricated component factories in the area and the city.
The Research Group has established the following two dynamic prediction and calculation models of annual demand through research..
