Brick-Concrete House Prefabricated Slab Floor

The floor slab of a brick-concrete house is not necessarily a prefabricated slab; it can also be a cast-in-place slab. The following provides a detailed introduction from the aspects of definition, characteristics, seismic performance, and application time:

Definition and Characteristics:

• Prefabricated Slab: It is a floor slab component pre-made in a factory according to design specifications and then transported to the construction site for direct installation. This manufacturing method allows for fast construction speed, significantly shortening the construction period. Moreover, due to mass production in the factory, the cost is relatively low. However, there are splicing gaps between the prefabricated slab sections, resulting in poor overall integrity.
• Cast-in-Place Slab: It involves directly supporting formwork at the construction site and pouring concrete into the formwork, which then forms the floor slab after curing and other processes. It can better integrate with structures such as walls, providing strong overall integrity and better load transfer and distribution capabilities.

Seismic Performance:

• Prefabricated Slab: It has poor seismic resistance. Under seismic action, the connection parts between prefabricated slabs are prone to loosening and breaking, leading to floor slab collapse. For example, during the 1976 Tangshan Earthquake, a large number of brick-concrete houses using prefabricated slabs suffered severe damage, with many floor slabs falling off, causing significant casualties and property losses. Experimental data shows that prefabricated slabs can only withstand a magnitude 6 earthquake and have relatively weak seismic resistance under the same seismic force.
• Cast-in-Place Slab: It has stronger overall integrity and better seismic performance. It can form an organic whole with the load-bearing structure of the house, better resisting seismic forces during earthquakes and reducing structural damage. Experiments indicate that cast-in-place slabs can withstand a magnitude 8 earthquake, and their seismic resistance is 2 to 3 times that of prefabricated slabs.

Application Time:

• Prefabricated Slab: It was widely used in houses built before 2003. At that time, due to limitations in construction technology and economic conditions, prefabricated slabs were widely applied because of their advantages of fast construction and low cost.
• Cast-in-Place Slab: After 2008, the country gradually phased out prefabricated slabs and promoted cast-in-place floor slabs. With the continuous progress of construction technology and the increasing requirements for the seismic performance of houses, cast-in-place slabs have gradually become the mainstream floor slab manufacturing method due to their good overall integrity and seismic performance. Nowadays, basically all newly built brick-concrete houses use cast-in-place slabs.