Prefabricated Concrete Floor Slab for Factory Building Roof

Prefabricated concrete floor slabs for factory building roofs typically use reinforced concrete hollow slabs or prestressed concrete circular-hole slabs, which have the characteristics of strong load-bearing capacity and convenient installation. However, it should be noted that in modern construction, prefabricated slab structures have gradually been replaced by safer frame or reinforced concrete structures.

Common Types and Prices

Prefabricated concrete floor slabs mainly fall into two categories:

1. Reinforced Concrete Hollow Slabs: These slabs reduce their self-weight through internal hollow designs while maintaining structural strength, making them suitable for factory building roofs with large spans. For example, the price of such slabs produced by Zhangqiu Bowen Flower Brick Factory is 24 yuan per meter.
2. Prestressed Concrete Circular-Hole Slabs: These slabs enhance crack resistance through prestressing technology, and the circular-hole design further optimizes material distribution, improving load-bearing efficiency. Similar products provided by Zhuozhou Penglei Trading Co., Ltd. are priced at 40 yuan per meter, and some customized models (such as those from Zhangqiu Bowen Flower Brick Factory) are also available at 24 yuan per meter.

Installation Technical Points

1. Hole Treatment and Formwork Support: The holes in the floor slabs need to be blocked with concrete blocks to prevent debris from entering. The reinforcing bars are bent upwards and then installed on the rigid formwork supports to ensure that the formwork is flush with the top surface of the beam, providing a stable foundation for subsequent pouring.
2. Reinforcing Bar Connection Strengthening: The reinforcing bars of the floor slabs need to be bent downwards at a 45-degree angle so that the reinforcing bars of adjacent slabs cross to form an integral whole. Full-length reinforcing bars are added at the crossing points and fixed by welding or binding to enhance the connection strength between the slabs and prevent local stress damage.
3. Support Distance Control: The support distance of the floor slabs on the wall is generally 8 centimeters. If the wall thickness is 240 centimeters, support is required on both sides at 8 centimeters each, leaving an 8-centimeter gap in the middle for pouring concrete to ensure coordinated stress between the wall and the floor slab.
4. Slab Joint Pouring Specifications: The slab joint spacing needs to be controlled in two parts: 2 centimeters at the bottom and 4 centimeters at the top. After the main construction is completed, high-strength concrete is used to pour the slab joints and fill them densely to prevent leakage and cracks.

Advantages and Disadvantages Analysis

• Advantages: Prefabricated slabs are produced in a standardized manner in factories, ensuring controllable quality. They can be directly installed on-site after transportation, significantly shortening the construction period, especially suitable for industrial projects with tight schedules.
• Limitations: Prefabricated slabs are integral structures with relatively weak seismic performance. Modern construction tends to adopt frame or reinforced concrete structures, forming a continuous load-bearing system through cast-in-place processes to improve overall safety.

Application Trends

Although prefabricated concrete floor slabs have been widely used in early industrial buildings, due to their structural limitations, newly built factories have gradually shifted to cast-in-place concrete or steel structure systems. Existing factories with prefabricated slabs need to regularly inspect the slab joints, support nodes, and reinforcing bar corrosion, and carry out timely maintenance to extend their service life.