Prefabricated Building Panels

Prefabricated building panels, also known as prefabricated slabs, were commonly used floor slabs in early 20th-century construction. They are engineering modules or panels that are still applied in some regions today.

I. Production and Definition of Prefabricated Slabs Prefabricated slabs are concrete prefabricated components produced and processed through standardized processes in prefabrication yards. During production, a hollow mold is first made using wooden planks. After reinforcing bars are arranged in the hollow part of the mold, the hollow area is filled with cement. Once dry, the wooden planks are knocked off to obtain the finished product. This industrial production method gives them the characteristics of uniform dimensions and controllable quality.

II. Types and Applications of Prefabricated Slabs There are various types of prefabricated slabs, including hollow prefabricated floor slabs, concrete load-bearing floor slabs, and reinforced concrete hollow slabs. The price range is from 12.0 yuan to 55.0 yuan, with special specifications (such as the Jingnanyuezhuo SP prestressed floor slab) being more expensive. Their application scenarios are wide-ranging. In addition to being used as building floor slabs, they can also be used as ditch covers beside highways and roof insulation layers. Although modern buildings mostly adopt frame structures or reinforced concrete structures, prefabricated slabs are still widely used in self-built houses in rural areas of some southern regions.

III. Specifications and Selection of Prefabricated Slabs for Rural Self-Built Houses The specifications of prefabricated slabs used in rural self-built houses need to be considered in combination with transportation and load-bearing requirements:

1. Length: Usually ranging from 3 meters to 4.2 meters, increasing by 30 centimeters per increment. Special customization is required for lengths exceeding 4.2 meters due to transportation limitations.
2. Width: Commonly available in two sizes: 50 centimeters and 60 centimeters.
3. Thickness: For ordinary rooms, a thickness of 12 centimeters is sufficient. For the second floor or load-bearing scenarios (such as placing heavy objects), a minimum thickness of 15 centimeters is required.

IV. Analysis of the Advantages and Disadvantages of Prefabricated Slabs

1. Advantages:
   • Low cost: The material and construction costs are significantly lower than those of cast-in-place concrete.
   • Fast construction: The prefabricated components can be directly installed, greatly shortening the construction period.
2. Disadvantages:
   • Poor durability: After about ten years of use, they are prone to cracking and water leakage due to thermal expansion and contraction or foundation settlement.
   • Weak earthquake resistance: Due to insufficient integrity, they are prone to breakage or collapse during earthquakes, posing safety hazards.

V. Usage Recommendations If prefabricated slabs are chosen, regular inspection and maintenance are required, and cracks should be repaired in a timely manner. In earthquake-prone areas or buildings that require long-term load-bearing, it is recommended to give priority to more stable structural forms such as cast-in-place concrete.