Large-Span Prefabricated Panel House

The following are key points about large-span prefabricated panel houses:

Characteristics of Composite Floor Slabs
Composite floor slabs commonly used in large-span prefabricated panel houses are formed by combining prefabricated panels with cast-in-place reinforced concrete layers. Their typical spans range from 4 to 6 meters, making them suitable for high-rise buildings and large-span structures. The prefabricated panels serve both as structural components and permanent formwork, while the thickness of the cast-in-place layer is determined based on the span, usually not less than 90 millimeters. This structure ensures both construction efficiency and overall structural stability through the combination of prefabrication and cast-in-place methods.

Key Points for Selecting Prefabricated Panels
For prefabricated panels with a span of 6 meters, strict selection of the panel type is essential. Ordinary cement panels are prone to bending and deformation when exceeding 3 meters, whereas prestressed panels enhance load-bearing capacity by pre-tensioning steel bars. A standard 120-millimeter-thick prestressed panel can support spans of over 7 meters. During design, professional engineers must calculate the floor slab's load-bearing capacity to ensure it is not less than 760 kilograms per square meter, with 500-megapascal high-strength steel bars used for reinforcement. During installation, the length of the prefabricated panel resting on the wall at both ends must be no less than 10 centimeters, and horse-shaped reinforcing bars should be inserted at the joints to enhance connection strength and prevent cracks or structural failure.

Application and Renovation Practices
The Beijing Changping Life Valley International Pharmaceutical Smart Manufacturing Park (Phase II) project, which commenced construction in March 2026, adopted prefabricated composite floor slab technology, demonstrating the efficient application of prefabricated panel houses in industrial buildings. In terms of renovation and upgrading, starting from 2026, safety upgrades for prefabricated panel houses will be steadily implemented: D-grade dangerous housing (overall danger) must be prioritized for demolition and reconstruction; C-grade dangerous housing (partial danger) can be reinforced, renovated, or rebuilt. The priority for renovation depends on the housing's safety condition, the degree of outdated living functions, the conditions for area renewal, and actual value, with old residential buildings that pose significant safety hazards or have severely outdated functions given priority.

Key Considerations
The design and renovation of prefabricated panel houses must strictly adhere to structural safety codes, with parameters such as span, load-bearing capacity, and material strength professionally calculated. During daily use, regular inspections of joints, resting points, and steel bar corrosion should be conducted to avoid overloading or unauthorized structural modifications, ensuring long-term safety.