Prefabricated Component Assembled Housing

Prefabricated component assembled housing is a form of construction that involves industrial production of building components and on-site assembly, offering advantages such as shortened construction periods and reduced pollution.

I. Definition and Types Prefabricated component assembled housing, also known as prefabricated modular construction, centers on the standardized production of building components (such as beams, slabs, walls, and columns) in factories, which are then transported to construction sites for assembly into complete structures using mechanical lifting and joining. Based on the method of component combination, there are three main types:

1. Panel-based Modular Construction: This type primarily uses prefabricated wall panels, floor slabs, and other planar components, which are assembled into spatial structures using connectors. It is suitable for multi-story residential buildings or office buildings.
2. Box-based Modular Construction: This approach uses complete spatial modules (such as bathrooms and kitchens) as units, which are directly stacked on-site. It is commonly found in standardized buildings like hotels and apartments.
3. Frame-based Modular Construction: This type employs prefabricated beams and columns to form a frame system, which is then filled with wall panels. It offers high flexibility and is suitable for large-span public buildings. The technical systems encompass prefabricated concrete structures (such as prefabricated shear walls and frames) and steel structures (such as light steel frame systems). The former relies on the strength of concrete components, while the latter utilizes the lightweight and high ductility of steel.

II. Construction Process and Characteristics The construction process is centered around industrial logic:

1. Foundation Treatment: For example, in rural villa projects, 5-ton foundation piles combined with footplates are used to ensure structural stability.
2. Component Lifting: Light cranes are employed to lift reinforced concrete walls or steel frames, with special brackets used to adjust verticality and horizontality, controlling errors to within millimeters.
3. Node Connection: Mortise-and-tenon joints are used for rapid connection between beams, while complex components like stairs are fixed using pre-embedded bolts, reducing on-site welding operations.
4. Gap Treatment: Gaps between components are grouted or filled with insulation materials to form an integrated structure, enhancing seismic resistance and airtightness. Typical cases show that the main structure can be completed in 14 days, shortening the construction period by more than 50% compared to traditional methods, while reducing construction waste by 70% and dust emissions by 30%.

III. Technological Development and Applications China's prefabrication technology originated in the 1950s and was initially used for factory and residential construction. However, it stagnated due to insufficient design standardization. In the 21st century, with rising labor costs and stricter environmental policies, the technology has experienced a resurgence:

• Vanke Group has developed a prefabricated shear wall residential structural system, increasing the prefabrication rate to over 60% and achieving full-chain collaboration in "design-production-construction".
• Policy Promotion: The Ministry of Housing and Urban-Rural Development's "14th Five-Year Plan for the Construction Industry" explicitly requires that by 2025, prefabricated buildings should account for more than 30% of newly constructed buildings, driving technological upgrades towards intelligence and greenness.

Currently, prefabricated component assembled housing has expanded from single-function buildings to complex structures, combining BIM technology and robotic construction to further break through limitations in on-site operational efficiency and precision.