What is a Prefabricated Slab in House Structure

A prefabricated slab is a widely used floor form in early 20th-century architecture, referring to a building component pre-made outside the factory or construction site.

Production Process

The production of prefabricated slabs begins with the creation of a hollow mold using wooden planks. Reinforcing steel bars are then placed within the hollow section of the mold according to design requirements, followed by the pouring of concrete. After the concrete has set and reached a certain strength, the mold is removed, resulting in the final prefabricated slab. This production method allows for centralized manufacturing in factories or specialized prefabrication sites, ensuring consistent quality and dimensional accuracy of the components.

Types

Prefabricated slabs are primarily categorized into solid and hollow types. Hollow prefabricated slabs achieve structural lightness by reducing the amount of concrete used in non-load-bearing sections. This design not only lowers material costs but also reduces the building's self-weight, imposing lower demands on the foundation and saving on foundation engineering expenses to a certain extent.

Characteristics

As a concrete prefabricated component, prefabricated slabs offer the advantages of convenient construction and low cost. During construction, they can be directly transported to the site for installation, eliminating the need for complex on-site processes such as formwork erection, steel bar binding, and concrete pouring. This significantly shortens the construction period and improves efficiency. Additionally, since prefabricated slabs can be mass-produced in factories, economies of scale can be achieved, reducing the cost per unit component.

Application Scope

Prefabricated slabs were once extensively used in building floors, roof slabs, highway ditch covers, and roof insulation layers. In early multi-story residential buildings, prefabricated slab floors were a common choice, meeting basic living and usage requirements.

Limitations

However, prefabricated slabs also have some notable drawbacks. Their seismic performance is relatively poor; under earthquake action, the connection points between prefabricated slabs are prone to damage, leading to floor collapse and posing a serious threat to human life and property safety. Their overall integrity is weak; since prefabricated slabs are combined through simple connection methods, they struggle to form a unified structural system, making them prone to cracking under heavy loads or complex stress conditions. Additionally, joint leakage is a common issue; improper treatment of the joints between prefabricated slabs can easily lead to rainwater leakage, affecting the building's functionality and durability.

Due to these limitations, modern house construction has gradually phased out prefabricated slab structures in favor of frame structures or reinforced concrete cast-in-place structures to enhance building safety, integrity, and durability.