Reinforcement and Renovation of Prefabricated Slab Houses

The reinforcement and renovation of prefabricated slab houses should be carried out comprehensively from multiple aspects, including structural assessment, construction reinforcement, plan customization, and functional upgrades. Details are as follows:

I. Structural Safety Assessment Before Renovation A comprehensive inspection of the old house is required, with a focus on the cracks and connection status of the prefabricated slabs:

1. Crack Detection: If the crack width at the production site of the prefabricated slab exceeds 0.3 millimeters, special treatment is required (such as grouting repair or steel plate reinforcement).
2. Connection Detection: Check the bolt connection status between the prefabricated slab and the ring beam. If the corrosion rate exceeds 30%, the bolts need to be replaced to ensure structural stability.

II. Construction Reinforcement Measures

1. Roof Renovation: Remove the original wooden roof and recast a concrete roof while maintaining the original height to improve waterproof performance and structural durability.
2. Wall Reinforcement:
   • Remove the original exterior wall tiles, repaint them, and perform steel bar planting and grouting to enhance the load-bearing capacity and tensile properties of the walls.
   • For areas with small wall cracks, grouting repair is adopted, while severe cracks require steel plate reinforcement.
3. Support System Construction: Set up steel pipe supports every 1.2 meters along the length of the prefabricated slab, and use H-shaped steel beams (with a cross-section of no less than 200*200 millimeters) for underpinning at key nodes to ensure construction safety.
4. Slab Joint Treatment: Remove the original joint filling material, implant No. 6 threaded steel bars, and pour C30 fine aggregate concrete to strengthen the slab joint connection.
5. Addition of Structural Columns: Add structural columns (with a cross-section of 240*240 millimeters) at the four corners of the house, and tie them with No. 6 and No. 8 steel bars and connect them to the floor slab to improve the overall seismic performance.
6. Demolition Principles: Adopt a phased demolition method of 'middle first, then sides', with a daily demolition volume not exceeding 30% of the total floor slab area. Monitor the stress changes in the support system in real-time, and prohibit heavy hammer impact demolition to avoid foundation damage.

III. Customization of Renovation Plans Formulate targeted plans based on the specific problems of the house:

• Unstable Foundation: Pile foundation reinforcement is required.
• Roof Leakage: Re-lay the waterproof layer.
• Overall Frame Reinforcement: For example, in the renovation case of a three-story prefabricated slab house in Zhejiang, the height was increased by 60 centimeters through frame reinforcement. After the frame solidified, the original prefabricated slabs and walls were demolished and replaced with new structures.

IV. Functional Upgrades Optimize the living experience on the basis of reinforcement:

• Sound Insulation Improvement: Use soundproof panels and double-glazed windows.
• Waterproof Optimization: Redesign the roof drainage system to ensure long-term waterproof performance.