Brick-Concrete Prefabricated Slab House

A brick-concrete prefabricated slab house is a hybrid structural system that utilizes brick walls and reinforced concrete beams, floor slabs, and other components for load-bearing. The vertical load-bearing components are constructed from bricks or masonry blocks, while the horizontal components, specifically the floor slabs, are prefabricated.

Main Advantages:

1. Simple Construction and Low Cost: Prefabricated slabs are produced in a standardized manner in factories, allowing for efficient on-site assembly. The techniques for brick wall construction and concrete pouring are well-established, and materials such as clay bricks and sand are readily available, resulting in an overall cost lower than that of frame structures.
2. Stable Performance: Brick walls and concrete components offer good durability and superior fire resistance compared to pure wooden structures. The prefabricated slabs typically contain air layers, providing better sound insulation and thermal insulation than cast-in-place floor slabs.
3. Wide Applicability: The structural height is generally limited to six stories or less, making it suitable for low- to mid-rise residential buildings, schools, office buildings, and other civilian structures. This type of housing particularly met the needs of urban housing construction in China during the mid- to late 20th century.

Key Disadvantages:

1. Weak Seismic Performance: Prefabricated slabs are connected to walls using mortar or a small amount of reinforcement, resulting in poor overall integrity. During earthquakes, connection failures can easily lead to slab collapse or wall cracking. In the 1976 Tangshan earthquake, the damage rate for such houses exceeded 80%.
2. Heavy Self-Weight and High Wet Work: Brick walls and concrete components increase the building's self-weight, imposing high demands on foundation bearing capacity. On-site masonry and pouring require significant amounts of water and are susceptible to weather conditions, leading to longer construction periods.
3. Low Spatial Flexibility: The load-bearing brick walls limit interior layout modifications, making it difficult to meet modern architectural demands for large open spaces.

Improvements and Current Status:
To enhance safety, the addition of structural columns and ring beams can form a "confined masonry" system, improving overall integrity. After the 2008 Wenchuan earthquake, China's "Code for Seismic Design of Buildings" explicitly mandated the phasing out of prefabricated slabs in favor of cast-in-place floor slabs, which offer better integrity and seismic resistance. Currently, a large number of brick-concrete prefabricated slab houses built in the last century still exist across the country. The focus of their renovation includes:

• Seismic Strengthening: Reinforcing walls with carbon fiber sheets or adding steel supports;
• Energy Efficiency Upgrades: Applying external insulation panels and replacing windows with double-glazed units;
• Functional Upgrades: Optimizing piping layouts to enhance living comfort.

Although such houses are gradually being phased out of the new construction market, scientific renovations can extend their service life and ensure居住安全 (living safety).