Steel Bonding Reinforcement for Prefabricated Slab Houses

Prefabricated slab houses can enhance their safety through steel bonding reinforcement under suitable conditions. Here are the details:

Principle of Steel Bonding Reinforcement: Steel bonding reinforcement is a structural reinforcement method that uses epoxy adhesives to bond steel plates to the surface of concrete members. Through the structural adhesive, the steel plate and concrete work together to bear loads, thereby improving the load-bearing capacity and stiffness of the members. For prefabricated slab houses, if only local load-bearing capacity is insufficient, steel bonding reinforcement is an effective option.

Construction Process: During construction, professional technicians use tools such as angle grinders and wire brushes to grind the surface of the floor slab base layer, removing loose layers, oil stains, and dust to ensure the base layer surface is flat, solid, and has the required roughness. Subsequently, construction personnel precisely prepare the structural adhesive, evenly apply it to the steel plates cut to the appropriate size, and quickly and accurately bond the steel plates to the predetermined reinforcement positions. When the steel plates are tightly bonded to the floor slab, they can significantly share the pressure borne by the floor slab, thereby improving its load-bearing capacity.

Applicable Conditions and Limitations:

• Not all prefabricated slab houses are suitable for steel bonding reinforcement. The load-bearing logic of prefabricated slab floors differs from that of cast-in-place floors. Most prefabricated slabs are one-way slabs, supported only at both ends, and the transverse slab joints basically do not bear transverse tensile forces. Therefore, the reinforcement plan should be formulated based on the actual safety appraisal results of the house to avoid blind reinforcement.
• If the house has been exposed to fire, early prefabricated slabs often use prestressed technology, with a steel reinforcement protective layer thickness of only 25 millimeters. When the fire temperature exceeds 650°C, the strength of the prestressed steel bars will almost completely be lost. At this time, reinforcement is difficult, costly, and the safety is difficult to guarantee. It is generally recommended to directly demolish the house.
• If structural cracking is caused by foundation settlement, the upper reinforcement of the prefabricated slab itself is very small, and the slab is prone to break at the supports after settlement occurs. Reinforcement around the perimeter cannot solve the fundamental problem, and the reinforcement cost may be close to the reconstruction cost, making it not worthwhile.