House Reinforcement - Prefabricated Panels
The reinforcement of prefabricated panels for houses requires selecting appropriate methods based on specific circumstances, as not all situations are suitable for perimeter reinforcement.
Common Reinforcement Methods When the load increase on a prefabricated panel floor is relatively small, carbon fiber can be directly adhered to the bottom of the hollow panel. Carbon fiber has high strength and is lightweight. By using a specialized adhesive to attach it to the panel bottom, it can effectively enhance the panel's bending resistance, increase its load-bearing capacity, and the construction is relatively simple with minimal damage to the original structure.
Alternatively, steel sections can be installed at the four corners beneath the prefabricated panels to transform the original structure into an octagonal support. Steel sections have high strength and rigidity. Through proper arrangement and connection, they can effectively share the load of the prefabricated panels and improve the overall load-bearing capacity of the floor, which is suitable for situations where the load increase is significant or the original structure's load-bearing capacity is insufficient.
In addition, the plywood reinforcement method is also a mature technique. This method involves placing plywood on both the upper and lower surfaces of the prefabricated panels and tightly connecting them to the panels using bolts and other fasteners to form a single unit that jointly bears the load, thereby increasing the floor's load-bearing capacity and rigidity.
Situations Unsuitable for Perimeter Reinforcement For prefabricated panel floors that have been exposed to fire, early prefabricated panels often used prestressed technology. When the fire temperature exceeds 650°C, the strength of the prestressed steel bars is almost completely lost. At this point, the structural performance of the prefabricated panels is severely compromised. Even if perimeter reinforcement is carried out, it is difficult to restore their original load-bearing capacity and safety. Moreover, the reinforcement is difficult and costly, so it is generally recommended to directly demolish them.
Prefabricated panel floors with structural cracks caused by foundation settlement are also unsuitable for perimeter reinforcement. The upper reinforcement of prefabricated panels is minimal, and after settlement occurs, the entire panel is prone to break at the supports. Perimeter reinforcement can only strengthen the perimeter of the panel and cannot address the overall structural issues caused by foundation settlement. The cost of reinforcement may even approach that of reconstruction, making it not worthwhile.
