How to Rectify Prefabricated Floor Panels in Houses
The rectification methods for prefabricated floor panels in houses should be determined based on the house safety appraisal grade and the actual situation, as follows:
If the house is appraised as Grade A or B and there are no major issues with the main structure, the approach of renovating old residential areas can be adopted. For example, for roof leakage problems, roof repairs can be carried out; for aging pipelines, new pipelines can be installed; if the fire protection does not meet the standards, fire protection rectification should be conducted; when conditions permit, elevators can also be added to improve living convenience.
If the house is appraised as a Grade C dilapidated building but still has room for repair, a maintenance and reinforcement approach is required. The reinforcement covers the strengthening of walls, beams, columns, floor panels, and foundations, as well as the improvement of seismic resistance. Specific measures include: special treatment for cracks wider than 0.3 millimeters at the production sites of the prefabricated floor panels; inspecting the connection status between the prefabricated floor panels and the ring beams, and replacing the bolts if the rust rate exceeds 30%; for the positions of panel joints detected in the structure, removing the original filling materials, implanting No. 6 deformed steel bars, and pouring C30 fine aggregate concrete; adding constructional columns at the four corners of the house, with the cross-section of the constructional columns generally being 240240 millimeters, using No. 6 and No. 8 steel bars for reinforcement and connecting them to the floor panels; during the construction preparation stage, a temporary support system needs to be erected, with steel pipe supports set every 1.2 meters along the length of the prefabricated floor panels, and H-shaped steel beams used as replacement steel beams at key nodes, with the cross-section of the steel beams being greater than or equal to 200200 millimeters.
If the house meets the conditions for expropriation and demolition, such as the need for land for road construction, subway construction, public facility construction, or the area is included in a clear demolition and reconstruction project, it may go through the expropriation procedure in accordance with the law. Three types of prefabricated panel houses will be given priority for demolition: first, those with damaged main structures of the prefabricated panel houses that cannot be repaired even through old house renovation; second, some prefabricated panel houses whose main structures are not damaged but cannot withstand natural disasters such as earthquakes and floods; third, those on land planned for municipal construction.
