by Japan believes that precast buildings are divided into: Precast concrete (PCA) and prestressed concrete (PC).
The advantages of PCA: high strength and high-quality concrete parts; Mass production of finalized components; Advantages of PC: concrete members form preloading stress; It shall be assembled by crimping.
PC in Japan is mainly used in precast frame structure, which adopts prestressed crimping, which is a “dry node” with fast assembly speed.
Key points: Joint non shrinkage mortar; Precast and cast-in-situ composite floor slab; Mortar anchor sleeve connection of column reinforcement.
China is still in the initial stage of building industrialization and new precast structures, and its research is not very systematic and sufficient.
The following aspects need to be further studied: (1) it is an inevitable condition for industrialized production to solve the problems of standardization and modeling of precast concrete structures from the source of standards and design, This requires relevant government departments and university research units to formulate standards and promote professional and industrialized production from the strategic layout of industrialization.
(2) Prepare and improve the design, production, construction, acceptance and testing standards of cast concrete structures as soon as possible, and determine the supporting design methods, manufacturing processes, construction guidelines and acceptance standards, so as to promote the maturity and popularization of technology.
(3) Study on precast concrete structure system.
From the domestic research and engineering application, there are many kinds of prefabrication technologies, resulting in various structural forms, and a relatively unified structural system has not been formed, resulting in difficulties in research and inconvenient promotion.
(4) Industrialized production of precast concrete components.
The standardization and modularization of components need to be further solved, which also involves a series of problems such as the connection mode between components, the structure of leak proof and thermal insulation, and the setting of corresponding connecting accessories.
(5) Key technical guidance for the engineering application of precast concrete structures.
For various types of precast components and the connection between components, how to ensure the structural performance and integrity of the assembly structure, there is still a lack of corresponding technical standards or specifications in China to provide reference, which restricts its engineering application to a great extent.
(6) Relevant universities and enterprises should cooperate with each other to jointly develop relevant technologies, share resources and form a certain industrial scale as soon as possible.
While improving the quality of precast concrete components, research and develop the manufacturing technology of integration of decoration and thermal insulation.
The connection technology between precast components of precast concrete structure shall simplify the connection structure as much as possible, reduce the uncertainty in construction, and achieve unified standards, interchangeability and interoperability on the premise of ensuring the safety and integrity of the structure…
