Special Prefabricated Panels for Building Houses

Special prefabricated panels for building houses were commonly used as floor slabs in early 20th-century construction. They belong to engineering modules or panels and are processed at prefabrication yards before being directly transported to construction sites for installation.

Manufacturing Process and Structural Types

When manufacturing prefabricated panels, a hollow mold is first made using wooden planks. After arranging steel bars in the hollow part of the mold, cement is poured in and allowed to dry. Finally, the wooden planks are knocked off to form the finished product. Their structures are divided into two types: solid and hollow:

• Hollow Structure: Lightweight is achieved by reducing the concrete in non-load-bearing parts. The hollow positions, which are not subjected to force, are designed to be hollow, reducing weight and saving costs.
• Solid Structure: The entire panel is filled with concrete, providing stronger load-bearing capacity but also higher weight and cost.

Application Scenarios and Historical Status

Prefabricated panels were once widely used in various scenarios:

• Infrastructure: Such as cover plates for ditches beside highways and roof insulation layers.
• House Construction: Before 1985, residential buildings in China often adopted prefabricated panel house structures, using prefabricated panels as the main components for construction.

Reasons for Obsolescence and Existing Issues

With the development of construction technology, prefabricated panels have gradually been replaced by frame structures and reinforced concrete structures for the following reasons:

• Poor Integrity: Cast-in-place structures, by pouring concrete on-site, provide better integrity and sturdiness for buildings.
• Performance Defects: Existing prefabricated panel houses generally have issues such as weak earthquake resistance and poor sound and heat insulation, with a service life of about 30-50 years.
• Policy Guidance: Since 2022, China has implemented renovation policies, focusing on repairing and renovating prefabricated panel houses and only demolishing buildings that meet the criteria for dangerous houses. Some regions have already initiated demolition work.

Market Status and Product Types

Currently, various types of prefabricated panels are still available on the market, including:

• Customized Concrete Hollow Panels: Adjustable in size and specifications according to needs.
• Prestressed Concrete Circular Hole Floor Panels: Enhanced load-bearing capacity through prestressed technology.
• Prefabricated Floor Panel Cement Reinforced Concrete Catch Basin Panels: Used for specific scenarios such as drainage systems. Prices for prefabricated panels vary among manufacturers and specifications, and selection should be based on actual needs.

As an early product of building industrialization, although prefabricated panels have gradually withdrawn from the mainstream market due to technological limitations, their characteristics of low cost and rapid installation still play a role in specific scenarios.