Concrete technology has been successfully applied in foreign countries. The technology application is relatively mature, and it meets the requirements of environmental protection, building energy conservation, wall innovation, etc., and through factory production, it can save materials and labor, and improve construction efficiency. Shorten the construction site cycle, improve the quality of construction projects, and reduce the effect of construction waste discharge.
I. Characteristics of precast concrete component technology Most of today's domestic building structures are designed as cast-in-place concrete structures. The more common structural forms include frame structure, shear wall structure, frame shear structure, core tube structure, and tube-tube structure. The common feature is that most of the components are cast-in-place, and only a few secondary components such as door and window lintels are prefabricated. Precast concrete component technology brings a whole new topic, and it is proposed to include exterior walls in the above structural forms. The components such as stairs, kitchen and bathroom, beam and even pillars are prefabricated components, assembled together during construction and processed by nodes to form the design and construction technology of the complete building. This technology has the following characteristics:
1. The components are pre-made in the factory, which saves the material loss caused by on-site pouring and the environmental pollution caused by the construction site, and reduces the construction waste discharge.
2. The prefabricated components are saved on site to save a lot of labor compared to the cast-in-place system, which improves the construction efficiency.
3. The exterior wall decorative surface and the outer window can be completed after the prefabricated exterior wall is formed. After the site assembly, the exterior decoration and the outer window are formed. There is no need to set up the external wall scaffold during the construction, which saves the cost and reduces the safety hazard.
4. Prefabricated components are used for construction and construction through industrial production, which can effectively reduce the production cost of construction projects.
5. The prefabricated components are uniformly standardized and produced in the factory. The quality of the prefabricated components is much more stable than the uncertainties. It has a significant effect on improving the overall project quality and improving the building quality.
Second, the application of precast concrete component technology in Hong Kong and Singapore
1. Application of precast concrete component technology in Hong Kong
Hong Kong's construction industry is constantly striving to keep pace with the world's most advanced construction development research – concrete component prefabrication technology. In recent years, the Hong Kong Housing Development Agency has been actively promoting the development of mechanized precast concrete building systems in the development of public housing to meet the requirements of users, improve the quality of construction, improve construction safety and enhance environmental awareness. Looking back at the early 1990s, the Hong Kong Housing Development Agency took the lead in the use of prefabricated concrete in high-rise residential buildings, namely the introduction of precast concrete façades, semi-prefabricated slabs and prefabricated stair members to enable concrete prefabricated components throughout the building. The usage ratio has increased to nearly 20%. Recently, based on the experience of overseas and residential construction technology, the Hong Kong Housing Development Agency has developed a series of advanced concrete prefabrication and pre-assembly systems to make the amount of precast concrete components exceed 60%.
2. The precast concrete building technology uses the pre-soil component technology in Singapore.
Precast concrete component technology is very popular in Singapore, with multiple components. Its use is very wide, and prefabricated components are used in almost all parts of the building's inner and outer walls, beams, columns, floors, etc., and the prefabricated components of the single building can reach more than 75%.
Due to Singapore's special geographical location and climatic conditions, the use of prefabricated components is very beneficial. First, its high temperature and high humidity climatic conditions have greatly shortened its curing time, and it has been cured in almost one day, effectively shortening the production cycle. Secondly, due to The local area is not in the seismic zone. There is no earthquake requirement in the local area. The connection between the components and other structures is relatively simple. The long-term use of the prefabricated components makes Singapore have a mature technical system and considerable experience in node processing.