Load-Bearing Capacity of the Floor in Prefabricated Slab Houses
The load-bearing capacity of the floor in prefabricated slab houses is typically 200-500 kilograms per square meter, with the specific value depending on a combination of factors such as materials, grades, dimensions, and usage scenarios. The following is an analysis from different perspectives:
Classification by National Standards: The designed load for prefabricated slabs used in ordinary residential buildings is 200 kilograms per square meter, suitable for daily living scenarios such as furniture placement and human activities. For commercial or industrial applications, the load-bearing capacity of prefabricated slabs can reach 500 kilograms per square meter, enabling them to support heavy equipment and goods, meeting higher load requirements.
Classification by Grade: Grade 1 slabs have a load-bearing capacity of approximately 400 kilograms per square meter, suitable for temporary storage and placement of light furniture. Grade 2 slabs have a load-bearing capacity of about 700 kilograms per square meter, meeting the daily living needs of general residential buildings, such as the placement of household appliances and activities involving multiple people, and are commonly used in residential construction. Grade 3 slabs have a load-bearing capacity of up to 1000 kilograms per square meter, specifically designed for heavy industrial buildings or special occasions, such as mechanical workshops and large warehouses, requiring the use of high-strength concrete and reinforced structures.
Influence of Thickness and Reinforcement: A 10-centimeter-thick prefabricated slab (with single-layer reinforcement) has a load-bearing capacity of approximately 200-300 kilograms per square meter, suitable for scenarios with small spans and light loads, such as balconies and partition walls. A 15-centimeter-thick prefabricated slab (with double-layer reinforcement) has a load-bearing capacity of about 400-500 kilograms per square meter, commonly used in floor slabs and workshop floors that require higher load-bearing capacity.
Special Scenarios and Limitations: For prefabricated slab houses built in the 1990s, the designed live load of the floor with prefabricated hollow slabs is generally 200 kg/㎡. Any floor height increase or other renovation modifications will significantly affect the remaining live load. For example, after increasing the floor height by 10 centimeters, the remaining live load may be less than 100 kilograms per square meter, but it can still meet the needs of general daily living. In addition, the load-bearing capacity is also constrained by factors such as concrete strength, span and support, and environmental influences. For example, C25 concrete is suitable for low-load scenarios, while C30 and above concrete is used in high-load areas. For every grade increase in strength, the load-bearing capacity can increase by 15%-20%. Shorter spans and continuous support (such as multi-column support) can improve the load-bearing capacity by 10%-20%. Long-term exposure to humid environments (such as basements and pools) may cause concrete carbonation, reducing the load-bearing capacity by more than 30%, necessitating waterproofing measures.
