by New year’s Day is coming in 2022, and the new year begins! Five years have passed since the plan to vigorously develop precast buildings in 2016.
However, at present, the mainstream precast buildings have found some deficiencies in practice, and there are still different voices on the development of precast buildings in the industry.
The direction of precast building in the future is the primary problem to be solved in the precast building industry.
It’s very important to move! This not only needs to solve the problems of space, structure and waterproof, but also needs to solve the problem of huge (large) earthquake risk.
It has been 15 years since we began to study precast buildings in 2007, and we have done nearly 14 years of work in giant earthquake response.
We have successively prepared standards such as technical specification for giant earthquake response and technical specification for precast composite connected concrete shear wall structures.
This article is specially published to talk about our understanding of the development of precast buildings in the future.
You are also welcome to discuss this issue and make a modest contribution to the future development of precast buildings.
Precast buildings are one of the important measures to achieve green and low-carbon in the construction field in China.
The state plans to vigorously develop precast buildings.
China will build about 600 million square meters of precast buildings in 2020.
However, there are still deficiencies in precast buildings, and there are still different understandings and judgments on the development of precast buildings in the industry.
At present, the precast buildings with grouting sleeve connection as the mainstream have the following two major disputes in the industry: 1) quality risk.
Shanghai Construction Engineering Safety and Quality Supervision Station conducted a special inspection on the construction quality of cast building structure engineering in 2021 (hjaq (2021) No.
50).
According to the test results, Shanghai general quality supervision station points out that there are quality defects in the grouting plumpness of reinforcement sleeves in some projects, random construction of node reinforcement due to unclear requirements for in-depth design, local strength of structural cast-in-situ concrete is lower than the design requirements, non-standard use and construction of sealing materials, improper selection of components and frequent quality problems of finished products, There are structural safety hazards in some projects.
Academician Xiao Xuwen proposed in “Experimental Study on seismic performance of assembled shear wall without vertical distributed reinforcement connection” in 2021 that there are many deficiencies in sleeve grouting connection, which are mainly reflected in the following aspects: 1) due to the adoption of fine reinforcement design in China, there are a large number of reinforcement to be connected to the wall, It is difficult to accurately place the reinforcement during the installation of the actual cast wall; 2) At present, due to the uneven technical level of industrial workers and the immature grouting quality detection technology, the actual on-site grouting quality is often difficult to guarantee, which is easy to cause potential safety hazards; 3) A large number of grouting sleeves also correspondingly increase the construction cost.
Such precast buildings are difficult to meet the requirements of China’s future development.
2) Earthquake risk.
China is located at the intersection of the circum Pacific and Himalaya Mediterranean seismic belts.
It is the most active area of intraplate earthquakes in the world.
In recent years, giant (large) earthquakes such as Wenchuan earthquake (ms8.02008) have occurred successively.
Nearly 90000 compatriots have died due to earthquakes since this century.
The 19th CPC National Congress clearly pointed out that “life is supreme, Safety first “.
In the future, precast buildings should also meet the requirements of earthquake safety in China.
Where is the future direction of precast buildings? The resolution of the CPC Central Committee on the major achievements and historical experience of the party’s Centennial struggle points out: “We must achieve high-quality development in which innovation becomes the first driving force, coordination becomes an endogenous feature, green becomes a universal form, openness becomes the only way, and sharing becomes the fundamental purpose, so as to promote the quality, efficiency and power changes of economic development.
In the future, precast buildings should take the road of high-quality development and meet the requirements of green and giant (large) at the same time Double requirements for earthquake safety.
We have been exploring high-quality precast buildings suitable for China’s national conditions.
Based on the practice of predecessors and cast buildings such as Frank Lioyd Wright and pier Luigi nervi, we put forward the concept of organic industrialized architecture and some specific technologies in 2017 after 10 years of efforts.
Buildings with the following characteristics can be called organic industrialized buildings: precast buildings with “applicable, green, healthy, intelligent and renewable” performance, which are built in an industrialized way with meeting customer needs as the core, can realize customer life safety and property safety in giant (large) earthquakes and other disasters, and have a service life of more than 100 years.
Organic industrialized buildings include six elements: safety, applicability, green, health, intelligence and regeneration.
This concept has been adopted by the “planning outline of Hebei xiong’an New Area” (it can be seen that our research results have been adopted by the “planning outline of Hebei xiong’an New Area”).
Unfortunately, so far, there is no strictly organic industrialized building in China.
Organic industrialized building is a concrete form of high-quality precast building in the future.
All localities have made some discussions on the high-quality development of precast buildings.
In the notice on standardizing the construction management of high-quality commercial housing projects (JJF [2021] No.
384), Beijing pointed out that the high-quality housing construction scheme consists of six parts: green building, precast building, ultra-low energy consumption building, healthy building, livable technology application and management mode.
In the 14th five year plan of Shanghai for precast buildings (hjbm [2021] No.
702), Shanghai pointed out: take precast buildings as the starting point, deepen the innovation, transformation and development of the construction industry, strengthen the application of information and intelligent technology, realize the upgrading and development of precast buildings from existing to excellent, and improve the project quality, safety, benefit and quality.
With the upgrading of precast buildings in China, high-quality precast buildings will continue to emerge..
