This is the prefabricated component production factory of the Shanghai Company of Yuanda Housing Industry Group, which was put into operation at the beginning of the year. Although there are only 2 assembly lines and 100 workers, the components produced each year can meet the needs of 600,000 square meters of prefabricated buildings. Since the beginning of this year, with the successive introduction of policies such as the "Shanghai Three-Year Action Plan for Green Building Development", Shanghai's prefabricated construction industry has entered the "fast lane".

Transformation and upgrading of traditional construction industry

The so-called prefabricated building is to prefabricate some components in the factory, and then transport the components to the construction site to assemble into a complete building. The principle is the same as the production of automobiles on the assembly line. Compared with traditional cast-in-place buildings, prefabricated buildings have high precision and can avoid the "common problems" of traditional buildings such as wall cracking and leakage. In addition, they have the advantages of short construction period, less pollution, saving resources and labor, and are recognized as traditional buildings. The direction of industry transformation and upgrading.

However, when BROAD Residential Engineering Shanghai Company was first established last year, the technical system it brought from the headquarters in other provinces encountered "unacceptable conditions" in Shanghai. In its original system, the wall of the prefabricated house is divided into two parts, the inner part is a 200 mm thick load-bearing shear wall, and the outer part is a 160 mm thick external wall. The external wall is similar to a "sandwich", with two layers of cement sandwiching a layer of thermal insulation material. This design has good thermal insulation and safety, but according to the relevant regulations in Shanghai, it will waste about 5% of the volume ratio. "In Shanghai, where 'an inch of land is an inch of gold', this 5% loss has become a 'stumbling block' for market promotion." Fan Yi, chairman of the company, said.

It took Yuanda Shanghai several months to adapt the original technical system, and finally produced the "Shanghai version" product. The new wall incorporates a piece of "bread" in the "sandwich" into the shear wall, the thickness of the wall is reduced to 300 mm, the loss of the volume ratio is reduced to 2%, and the thermal insulation effect is not affected, and the effective cross-sectional area of ​​the shear wall is not affected. Change.

In the second half of last year, BROAD Residential Engineering won the first prefabricated commercial residential project in Shanghai with new products - Jinhui Fengxian South Bridge Xinyuan Project, which is expected to be completed next year; since then, it has successively won prefabricated public buildings such as Lingang staff dormitory. projects, as well as prefabricated office building projects such as Pengxin Zhigu.

While the market is gradually opening, BROAD Housing has developed the sixth-generation technical system featuring "full prefabricated shear walls". This technology can increase the building prefabrication rate to 70% or even more than 80%, and the construction period is shorter and the house quality is higher. Fan Yi said, "At present, the technology is ready. After the relevant standards are released in October, an office building project built with the sixth-generation technology will be launched in Shanghai within this year."

100,000 square meters is the "critical line"

The cost of prefabricated buildings is slightly higher than that of cast-in-place buildings, which is a major obstacle to the promotion of prefabricated buildings in Shanghai in recent years. To solve this problem, we must intervene from the design source.

"At first, some architectural design institutes were not very interested in prefabricated building projects, because some ready-made atlases could not be used, so they had to redesign." Fan Yi said, but when the "Three-Year Action Plan" was issued, it was stipulated that from 2016 onwards In principle, all the new civil buildings within the outer ring will be prefabricated buildings, and these design institutes will suddenly become "enthusiastic". Taking advantage of this opportunity, some employees of BROAD Residential Industry entered the cooperative design unit as "consultants" to help designers complete the design from the perspective of industrial production.

Zhou Dongling, president of the East China Design Institute of Yuanda Housing Industry, told reporters that the cost per square meter of prefabricated buildings is 200 to 500 yuan more expensive than that of cast-in-place buildings, but if a design scheme and new technology system suitable for splitting are used, the prefabrication rate of construction is 50%. For example, when the construction area reaches 100,000 square meters, the cost can be basically the same as that of ordinary buildings.

Since the beginning of this year, BROAD Residential Industry Shanghai Company has developed rapidly. The total construction area of ​​the projects undertaken in Shanghai has reached nearly one million square meters. As a supplier of prefabricated components, it provides "rations" to many developers such as Vanke, Jinhui, and Xuhui. With the development of prefabricated buildings in Shanghai, the market demand for prefabricated components will increase significantly in the future. In this regard, BROAD Residential Industry Shanghai Company plans to build a larger and more advanced factory after the Spring Festival next year, with 10 fully automatic flexible assembly lines. The expected annual production capacity can meet the needs of 3 million square meters of prefabricated buildings, and the annual output value can reach 2.5 billion yuan.