Reinforcement of Prefabricated Slab Structure Houses

The reinforcement of prefabricated slab structure houses should comprehensively employ various methods based on the actual condition of the house to enhance structural safety and seismic resistance. The specific measures are as follows:

1. Foundation Reinforcement

Enhance the bearing capacity of the foundation by expanding its size, deepening it, or adding steel reinforcement mesh. Simultaneously, inject reinforcement agents or sealing materials to improve the foundation's seismic performance. For example, in areas with soft soil foundations, deepening the foundation can effectively reduce the risk of foundation settlement.

2. Structural Reinforcement

1. Reinforcement of Key Components: Install steel beams, columns, or plates at positions such as walls, stairs, and roofs to enhance overall strength and stiffness. If the seismic resistance of the walls is insufficient, reinforced concrete can be injected to form a composite structure.
2. Floor Reinforcement:
   • When the load increase is minimal, carbon fiber can be adhered to the bottom of hollow slabs or additional steel beams can be installed to change the stress pattern.
   • Increase the floor section: Pour a layer of reinforced concrete with a thickness of ≥40 mm on the surface and bottom of the prefabricated slab to directly enhance its bearing capacity.
   • Plate-adhered steel plate method: Suitable for flexural members, but attention should be paid to the potential for separation between the steel plate and concrete. Special adhesives should be used, and regular inspections should be conducted.

3. Frame Reinforcement

Install metal frames on the exterior walls of the house to form an overall support system. Fill the frames with reinforcement agents or sealing materials to enhance seismic resistance. This method is suitable for multi-story prefabricated slab houses and can significantly improve lateral stiffness.

4. Seismic Isolation Reinforcement

Install spring isolators, rubber isolators, or other devices in the foundation or structure to isolate seismic energy input and reduce the impact of horizontal and vertical seismic forces on the house. For example, rubber isolation bearings can reduce seismic acceleration by 30%-50%.

5. Steel Bar Reinforcement

Embed steel bars in key components such as walls, stairs, and beams and columns to form a reinforced concrete composite structure. For example, embedding Φ6 threaded steel bars in wall cracks and pouring fine aggregate concrete can effectively inhibit crack propagation.

6. Construction Process Reinforcement

1. Structural Inspection and Assessment: Focus on inspecting the crack width of prefabricated slabs (cracks >0.3 mm require treatment) and the corrosion rate of connecting bolts with ring beams (corrosion rates >30% require replacement).
2. Temporary Support System: Before construction, install steel pipe supports every 1.2 meters along the length of the prefabricated slab, and use H-shaped steel beams (section ≥200×200 mm) for support at key nodes.
3. Slab Joint Treatment: Remove the original filling material, embed Φ6 steel bars, and pour C30 fine aggregate concrete.
4. Addition of Constructional Columns: Add 240×240 mm constructional columns at the four corners of the house, using Φ6 and φ8 steel bars for binding and connecting them to the floor slab.
5. Demolition Control: Follow the principle of 'middle first, then sides,' with a daily demolition area ≤30% of the total floor slab area. Continuously monitor the support stress and prohibit demolition by heavy hammer impact.