Prefabricated Slab Building Structure

The prefabricated slab building structure is a residential building form that primarily uses a brick-concrete structure and employs prefabricated concrete slabs as the main floor components. The specific structural characteristics are as follows:

1. Structural Form
Prefabricated slab buildings are centered around a brick-concrete structure, with walls mostly being load-bearing brick walls. The floor slabs are factory-prefabricated concrete slabs (divided into solid and hollow types). Hollow prefabricated slabs achieve lightweighting by reducing the non-load-bearing concrete portion, but the overall structural stiffness is lower, relying on the load-bearing capacity of the walls. The prefabricated slabs are connected to the load-bearing walls through steel bars or concrete, forming an overall load-bearing system. However, the joint connection strength is weaker than that of cast-in-place structures, resulting in insufficient seismic performance (the seismic level is usually lower than that of cast-in-place structures).

2. Floor Plan Layout and Spatial Limitations
Limited by the standard dimensions of prefabricated slabs (such as a span of 3-4 meters), the floor plan design is relatively fixed, with smaller room spans and poor north-south ventilation. The floor height is usually 2.6-2.8 meters, and the spatial layout is compact, making it difficult to achieve large-span or flexibly partitioned interior designs. For example, the areas of main functional zones such as living rooms and bedrooms are limited, and since most walls are load-bearing, the flexibility for renovation is low. Removing or modifying walls may compromise structural safety.

3. Load-Bearing Method and Structural Dependency
The walls bear the main vertical loads, and the floor slabs transfer the loads through the connection between the prefabricated slabs and the load-bearing walls. This structural form results in a single load transfer path, placing high demands on the integrity of the walls. If local walls are damaged (such as cracking or removal), it may trigger a chain reaction, affecting the overall stability. In addition, prefabricated slab buildings are sensitive to uneven foundation settlement and are prone to slab cracking or wall deformation due to foundation problems.

4. Advantages, Disadvantages, and Service Life
The advantages of prefabricated slab buildings lie in their low cost and short construction period, making them suitable for rapid construction needs. However, they have defects such as poor integrity and weak seismic performance. Their service life is generally 30-50 years. Affected by factors such as material aging and updates in design standards, the later maintenance costs are relatively high. For example, the joints between prefabricated slabs are prone to cracking due to temperature shrinkage or load effects and require regular maintenance. In areas with insufficient seismic fortification, the damage risk of old prefabricated slab buildings during earthquakes is significantly higher than that of cast-in-place structures.

5. Applicable Scenarios and Renovation Limitations
Prefabricated slab buildings are commonly seen in urban residential buildings from the 1970s to the 1990s, and this technology has been gradually phased out in newly built residential buildings. If renovation is required, it is necessary to strictly follow the principle of structural safety: It is prohibited to remove load-bearing walls or make significant changes to the floor slab layout. Only local adjustments to non-load-bearing walls are allowed. Reinforcement measures (such as adding structural columns or carbon fiber cloth reinforcement) must be evaluated and implemented by professional institutions to ensure structural safety.