Construction of Concrete Prefabricated Panel Houses

The construction of concrete prefabricated panel houses requires adherence to standardized procedures, covering aspects such as construction preparation, installation, gap treatment, and roof treatment, while also considering the overall structural safety and modern alternative solutions.

1. Construction Preparation

1. Material Selection: Prioritize the use of prefabricated panels produced by reputable large manufacturers, ensuring that the steel bars are prestressed, the concrete strength is not less than C30, and the specifications and quantities of steel bars comply with national standards.
2. Appearance Inspection: The surface of the prefabricated panels must be free from defects such as cracks, honeycombs, and holes to avoid structural safety hazards caused by material issues.

2. Installation Process

1. Support Length: When placing prefabricated panels on concrete components (such as ring beams), the support length must be ≥80mm; when placing them on walls, the support length must be ≥100mm to ensure stability.
2. Gap Treatment: A gap of 20-40mm must be left between two panels. After installation, the lower ends of the panels should be grouted (filled with cement mortar) to enhance adhesion; the holes at both ends of the prefabricated panels in the wall should be filled with concrete to prevent water leakage.
3. Usage Restrictions: It is strictly prohibited to arbitrarily cut holes or slots in the prefabricated floor slabs, and they must not be used in damp areas such as kitchens and bathrooms to avoid compromising structural integrity.

3. Gap Treatment

1. Cleaning and Pouring: Debris inside the panel gaps must be thoroughly cleaned. First, pour cement mortar and vibrate it densely; if the gap is large, pour concrete on-site and cure it. It is forbidden to fill gaps with bricks to avoid affecting structural strength.

4. Roof Treatment

1. Anti-Leakage Measures: Preferably use a cast-in-place roof; if using prefabricated panels, arrange a steel bar mesh on the roof and pour 6-8mm thick crushed stone concrete to enhance water resistance.

5. Overall Structural Considerations

1. Scope of Application: Prefabricated panel houses have poor overall integrity and weak seismic performance, making them only suitable for low-rise brick-concrete houses in non-seismic areas.
2. Policy Orientation: Existing prefabricated panel houses have issues such as weak seismic resistance and poor sound and thermal insulation. Since 2022, China has implemented a policy of renovation and transformation, focusing on repairs and upgrades, and only demolishing buildings that meet the criteria for dangerous houses.

6. Modern Alternative Solutions

1. Cast-in-Place Concrete and Prefabricated Buildings: Cast-in-place concrete structures have strong overall integrity and excellent seismic performance; prefabricated buildings use factory-prefabricated components, shortening the construction period by 30% and offering better seismic resistance, gradually replacing traditional prefabricated panel houses.