Are Prefabricated Panels Used for House Floors in Sichuan?

In some scenarios in Sichuan, prefabricated panels are still used, but their use for house floors is restricted.

Application Scenarios of Prefabricated Panels in Sichuan

In Sichuan, prefabricated panels find certain applications in rural self-built houses and small-scale municipal projects. For example, in places like Deyang and Guangyuan in Sichuan, many villagers use prefabricated panels for floor slabs when building new houses. These panels can bear a load of 200 - 300 kg/㎡, meeting the requirements for daily living. Small-scale municipal projects such as community fences, rural roadside ditches, and temporary sheds also commonly use prefabricated panels. Small prefabricated components (such as cover plates and stop blocks) for mountainous bridge culverts also often use prefabricated panels due to their corrosion resistance and adequate strength, which are suitable for Sichuan's mountainous and watery geological conditions.

Disadvantages of Prefabricated Panels

• Poor Seismic Performance: The floor slabs of prefabricated panel houses are composed of multiple prefabricated panels spliced together, with weak connections between the panels. During an earthquake, each panel is likely to act independently and collapse. In the Wenchuan earthquake, prefabricated panel houses suffered severe damage.
• Short Service Life: Manufacturers claim that prefabricated panels can last for 50 years, but in reality, it is good if there are no major problems after 20 years. In rainy southern regions, issues such as water leakage, steel bar corrosion, and concrete spalling may occur after about 10 years.
• Common Water Leakage and Cracking: The gaps between prefabricated panels are filled with cement mortar. Over time, due to thermal expansion and contraction and foundation settlement, cracks are inevitable at the joints.

Policies and Recommendations on the Use of Prefabricated Panels in Sichuan

The country began to gradually phase out prefabricated panels as early as 2002, and Sichuan has banned the use of prefabricated concrete panels for floor slabs since 2005. For rural self-built houses, in terms of seismic fortification intensity, most rural areas in Sichuan belong to the sixth-degree seismic fortification zone. For small-span houses with two floors or less, high-quality prefabricated panels can be used, but reinforced concrete ring beams must be set up to enhance the overall integrity. For areas with a seismic fortification intensity of seven degrees or above, it is recommended to directly choose cast-in-place slabs. In terms of room span, for ordinary bedrooms with a span of less than 3.6 meters, prefabricated panels can be barely used, but cast-in-place slabs are more stable. For living rooms and master bedrooms with a span of 3.6 to 4.8 meters, it is recommended to use cast-in-place slabs or thickened prefabricated panels with structural reinforcement. For large-span living rooms with a span of more than 4.8 meters, cast-in-place slabs must be used. In terms of budget and time balance, if the budget is ample and there is sufficient time, choose cast-in-place slabs. If the budget is limited and quality is not to be sacrificed, a compromise solution can be considered, such as using cast-in-place strips below load-bearing walls and prefabricated panels in the middle area of the floor slab.