House Prefabricated Panel Splicing Methods
The splicing methods for house prefabricated panels mainly include three types: wet connection method, dry connection method, and hybrid connection system. The specific operations and key points are as follows:
Wet connection method is the most widely used approach in the splicing of prefabricated panels. During construction, a cast-in-place strip with a width of 50-100mm needs to be reserved at the joint of the prefabricated panels. A framework is formed by arranging connecting steel bars with a diameter of 8-12mm, and then micro-expanding concrete with a strength grade not lower than C30 is poured. This material can effectively compensate for concrete shrinkage and reduce the risk of cracking. After pouring, a 28-day standard curing period is required to ensure that the concrete reaches the designed strength. This method achieves rigid connections between prefabricated panels through the cast-in-place layer, offering excellent overall load-bearing performance and is particularly suitable for areas with high seismic fortification requirements.
Dry connection method includes two forms: bolt connection and welding connection. Bolt connection requires embedding M16-M24 high-strength bolts at the edges of the prefabricated panels, achieving mechanical fixation through steel connectors. During construction, a torque wrench is used to tighten the bolts to 120-150N·m to ensure connection stiffness. Welding connection is designed for galvanized steel floor panels. A 20mm welding margin needs to be reserved at the panel edges, and CO₂ gas shielded welding is used for full-penetration welding. The height of the weld must not be less than 6mm to ensure that the weld's load-bearing capacity meets the design requirements. Dry connection offers the advantages of fast construction speed and no need for a curing period, but strict control over processing accuracy and installation quality is required.
Hybrid connection system combines the efficiency of dry construction with the overall performance of wet construction. This system employs pre-stressed steel strand tensioning technology, controlling the tensioning stress at 0.7fptk (where fptk is the standard value of the steel strand's tensile strength) to create a pre-compressed stress state in the prefabricated panels, enhancing the structure's crack resistance. Simultaneously, it coordinates with cast-in-place strip construction to further strengthen node connections. This method is suitable for large-span, heavy-load prefabricated structures and can effectively coordinate deformation differences between prefabricated components.
Quality control points include: Before splicing, the flatness of the prefabricated panels must be checked, with a deviation not exceeding 3mm; In seismic fortification areas, shear-resistant steel bars or energy dissipation devices should be added according to regulations; Joints must undergo waterproofing treatment, which can be achieved by applying polyurethane waterproof coating or laying waterproof membranes; All construction processes must comply with the mandatory provisions of the "Technical Specification for Prefabricated Concrete Structures" (JGJ1-2014) to ensure structural safety and reliability.
