Prefabricated Slab Brick-Concrete Structure House

A prefabricated slab brick-concrete structure house is a hybrid structural system where load-bearing is shared by brick walls and reinforced concrete beams and floor slabs, with the floor slabs being prefabricated hollow slabs. It features simple construction, low cost, but poor overall integrity and earthquake resistance.

Structural Composition and Characteristics
The vertical load-bearing components of a prefabricated slab brick-concrete structure house are walls constructed from bricks or blocks, while the horizontal load-bearing components are reinforced concrete beams and prefabricated hollow slabs. The prefabricated floor slabs are installed on the walls through simple overlapping, lacking effective connections between components, resulting in weak overall structural integrity. Although this design simplifies the construction process and reduces construction costs, it has insufficient lateral force resistance and is prone to damage under earthquake action.

Earthquake Resistance Deficiencies
The earthquake resistance of this structural system is poor, primarily manifested in the following aspects:

1. Weak connections of prefabricated floor slabs: The floor slabs are only fixed to the walls through simple overlapping, making them prone to displacement or detachment under horizontal forces during earthquakes.
2. Staircases as weak points: Staircases have open spaces and insufficient wall constraints, making the risk of prefabricated floor slab detachment and wall collapse during earthquakes significantly higher than in other areas. For example, in the 1976 Tangshan earthquake, such houses suffered extensive casualties due to staircase damage.
3. Inadequate structural measures: Houses built earlier generally lack seismic components such as structural columns and ring beams, further weakening the overall structural integrity. Houses built around 1978 did not even have any seismic structures, with extremely low strength in mortar and bricks; those built around 1984 saw slight improvements but still did not meet seismic requirements.

Historical Evolution and Code Updates
With in-depth research on earthquake resistance, China's building codes have gradually improved:

• Houses built around 1995 began to incorporate structural columns and ring beams at every other floor, improving earthquake resistance to some extent, but still essentially remaining prefabricated slab structures with limited quality improvements.
• After the 2008 Wenchuan earthquake, the state urgently revised seismic codes, explicitly requiring the elimination of prefabricated floor slabs and the comprehensive promotion of cast-in-place floor slab systems. Cast-in-place floor slabs form a continuous structure through integral pouring, significantly enhancing the lateral force resistance and overall integrity of houses, becoming the mainstream choice for current seismic design.