1.

An intuitive feeling of the basic situation of visiting the PC residential project in Tai Kok Tsui, Hong Kong: there are more than 50 houses in the whole community, each of which is a 58 storey super high-rise house, and the standard house type of 8 households in each unit, all of which adopt the standard PCF exterior wall system.

Cracks and large deformation will occur during transportation, hoisting and other construction processes, so reinforcement equipment must be adopted to prevent member damage, which will increase the construction cost.

（3） Comparison of the relationship between PCF and the main body of the structure PCF in Hong Kong model is a pure external component and does not participate in the stress work of the main body of the structure, so the construction and reinforcement is relatively simple.

Specific operation measures: in the B04 plot project of Shanghai Vanke Jinli City, which was independently designed by Shanghai Zhongsen, Chinese Academy of design, the following measures were taken by integrating two PC construction methods and combining the characteristics of 90 small houses: • the main structure adopts shear wall system to make the indoor small space as complete as possible.

• In terms of the relationship between PC and the main structure, considering that PC does not participate in the main work and is purely plug-in, the project can be approved by relevant departments and legalized as soon as possible in the case of tight construction period and unable to carry out experimental inspection.

Hong Kong PC technology in order to support the implementation of housing industrialization, the Hong Kong government offers a 10% discount on the floor area ratio index of projects using PC technology compared with projects without PC system.

Except for the five parts of balcony, staircase, bay window, air conditioning board and PCF wallboard, beams, columns and floors, including the overall toilet and overall kitchen, can be used.

The pure Japanese PC structure system can not be fully used under the requirements of the existing national specifications.

(II) comparison of member reinforcement methods: the PCF members of Hong Kong model adopt ordinary straight anchor tie bars, the concrete slab has no reinforcement structure, the stiffness of precast members is small, and the strength can not be guaranteed.

PC technology has long been applied in China, but there is no corresponding technical specification and policy support at present, Therefore, how to integrate and match foreign advanced technology with China’s existing design standards, and finally cooperate with relevant departments to form industry standards, the design unit needs to make a lot of research and test work through the parts factory and construction site, so as to truly master the technology and widely apply it in domestic projects.

Therefore, the evaluation of whether Japanese buildings adopt PC does not simply refer to which components, but depends on the percentage of PC, such as 80% PC, or even 100% PC, The whole building is factory assembled.

Straight anchored reinforcement is an open tie bar with relatively simple structure, which is only suitable for non seismic areas such as Hong Kong.

There is no corresponding calculation software, checking calculation method and corresponding specifications to follow.

（4） Comparison of application scope: the Hong Kong PC model is a model that has been imitated and simplified on the basis of the Japanese model in recent years to adapt to the local situation of Hong Kong.

Comparison of application scope of PC: PC structural components in Hong Kong mainly include five parts: balcony, staircase, bay window, air conditioning board and PCF wallboard, which are mainly used in high-rise residential buildings and apartments, mostly shear wall structural system; At present, the application of PC components of beams, columns and floors is only used in a small number of frame structures such as primary and secondary schools with less than five floors.

At the same time, the Hong Kong building supervision and buildings department is specially established to carry out quality control and quality supervision on PC.

Site photos of Hong Kong PC project ▲ Tai Kok Tsui residential project 2.

The PCF of Japanese model can stack a certain thickness inside the PC with the reinforcement protective layer of structural exterior wall or frame column, so as to reduce the thickness of exterior wall and increase the available area.

Compared with the Japanese model, it is relatively rough, simple nodes, less exquisite technology than Japan, but there are no normative restrictions and strong operability.

Site photos of Japanese PC project: a rough comparison between Japanese model and Hong Kong model (I).

It is roughly estimated that the scale of the project is 2-3 million square meters of construction area.

• In terms of PC application scope, refer to the Hong Kong model, the peripheral protection system is in the form of pure PCF, and the stair flight is PC component.

There are not many restrictions on the structural components of PC in Japan.

PC technology precast concrete component technology ▼▼ through the study of customer needs and product finalization, we can realize the production mode of factory prefabrication and on-site assembly, with the purpose of improving product quality and performance, so as to improve product production efficiency.

• The thickness of PC exterior wall shall be reduced as much as possible, and the Japanese PCF’s rich calculation experience and careful reinforcement scheme shall be brought into play to reduce the original 95mm to 85mm, so as to reduce the thickness of exterior wall and increase the use space..

PC construction method has formed a complete and reliable design, production and construction process.

The truss reinforcement is a closed tie s reinforcement, which can make the precast members and the main structural members overlap more firmly, have stronger integrity and have good seismic resistance, It is suitable for earthquake resistant areas.

We cannot add a part of PCF into the calculation of the main body of the structure.

Through the investigation in Hong Kong, the thickness of PCF plate is mostly 100mm.

The PCF members of the Japanese model adopt vertical and horizontal two-way truss reinforcement, which can ensure that the precast members have sufficient stiffness and strength during film removal, transportation, hoisting and storage, and will not produce cracks and excessive deflection deformation.

Thread Swivel Eye

• At the same time, give full play to the advantages of Japanese PC construction method, with meticulous treatment of detail nodes, good safety performance, firm waterproof measures for joint joints, and more beautiful and humanized allocation of external components.

In Japan, major construction groups have perfect design and manufacturing methods, which is equivalent to industry standards; It is backed by the empirical data accumulated through the strong test base and practical projects of these construction groups; Japan is a country with many earthquakes.