Prefabricated Earthquake-Resistant Housing

Prefabricated earthquake-resistant housing is constructed by combining prefabricated building technology with seismic design standards. Its earthquake resistance is influenced by the construction era, structural type, and reinforcement measures, and can be enhanced through rational design.

Characteristics of Prefabricated Building Technology

Prefabricated buildings are produced industrially with building components assembled on-site. The main types include panel prefabrication, box prefabrication, and frame prefabrication. Modular buildings, as a more integrated model, are manufactured in factories and then assembled on-site, offering advantages such as shorter construction periods, controllable quality, and energy efficiency. For example, a public housing project in Shenzhen used 6,028 concrete modules for assembly, reducing the construction and delivery period from 2.5-3 years to just 1 year.

Factors Affecting Seismic Performance

1. Construction Era: Prefabricated panel houses built before the 1980s have lower seismic standards and can currently only withstand earthquakes of magnitude 6. Newly constructed prefabricated houses can have their seismic capacity increased to magnitude 7, but still fall short of the overall integrity of cast-in-place reinforced concrete structures.
2. Structural Types:
   • Frame-Shear Wall Structures: In multi-story and high-rise reinforced concrete buildings, shear walls are arranged to work in conjunction with the frame, significantly reducing inter-story displacements under seismic action.
   • Multi-Story Masonry Buildings: These primarily rely on transverse walls for load-bearing, with the load-bearing transverse walls also serving as lateral seismic walls.
   • Bottom-Frame Brick Buildings: Suitable for structures with different materials, strength, and stiffness discontinuities between upper and lower levels, but with strict seismic design requirements.
3. Reinforcement Measures: Overall integrity is enhanced through refined design (e.g., millimeter-level error control) and high-standard connection techniques. For example, laying steel mesh or installing seismic isolation bearings at joints can increase seismic capacity to magnitude 7.

Technical Standards and Regulations

Since issuing its first seismic design code for buildings in 1974, China has continuously revised and improved it. According to the "Seismic Design Code for Buildings" implemented in 2002, buildings in areas with a seismic intensity of 6 degrees or higher must undergo seismic design, aiming to ensure "no damage in minor earthquakes, repairable damage in moderate earthquakes, and no collapse in major earthquakes."

Practical Application Cases

Prefabricated earthquake-resistant housing has been widely used in residential projects, public housing, and overseas projects. For example, the Nanjing Jindi Yufang project adopted a prestressed prefabricated concrete assembled integral frame structure system, demonstrating the integration of prefabricated technology with seismic-resistant structures.