Load-Bearing Standard for Prefabricated Houses

The load-bearing standard for prefabricated houses is influenced by multiple factors and does not have a fixed value. The common load-bearing range for prefabricated slabs is between 200 and 1000 kilograms per square meter. The specific standard needs to be comprehensively evaluated based on factors such as the type of prefabricated slab, span, reinforcement, and concrete grade. Here is a detailed explanation:

1. Classification by Prefabricated Slab Type

• Concrete Hollow Slabs: According to national standards, their load-bearing capacity is between 200 and 250 kilograms per square meter. Due to their internal hollow structure, these slabs are relatively lightweight but have limited load-bearing capacity, making them suitable for ordinary residential buildings or temporary structures with low load requirements.
• Solid Prefabricated Slabs: Their load-bearing capacity ranges from 250 to 300 kilograms per square meter. If produced by large manufacturers such as Jianhua Building Materials and China Railway 14th Bureau Group, with sufficient reinforcement and a concrete grade of C30 or higher, the load-bearing capacity can be increased to 300 kilograms per square meter, suitable for scenarios with slightly higher load requirements.
• Prestressed Prefabricated Slabs: For spans within 3 meters, the load-bearing capacity is between 300 and 400 kilograms per square meter; for spans over 4 meters, it decreases to between 250 and 300 kilograms per square meter. By using prestressed technology to improve crack resistance, their load-bearing capacity is 20% higher than that of ordinary prefabricated slabs of the same span, making them suitable for large-span buildings.

2. Classification by National Standard Grade

• Grade I Slabs: With a load-bearing capacity of 400 kilograms per square meter, they are mostly used in ordinary residential buildings to meet basic load requirements such as daily furniture and personnel activities.
• Grade II Slabs: With a load-bearing capacity of 700 kilograms per square meter, they are suitable for residential or commercial buildings with higher load requirements, such as warehouses for storing heavy items and equipment rooms.
• Grade III Slabs: With a load-bearing capacity of 1000 kilograms per square meter, they are mainly used in high-rise buildings or special industrial buildings that need to withstand extreme loads such as large equipment and heavy materials.

3. General Standard for Residential Floor Slabs The load-bearing standard for residential floor slabs is usually 200 kilograms per square meter, but a certain margin is reserved in actual design. Short-term overloading to around 300 kilograms generally does not cause structural damage. However, long-term overloading or concentrated loads (such as stacking heavy items) may lead to floor slab cracking or deformation, and such behaviors should be avoided.

Summary: The load-bearing standard for prefabricated houses needs to be determined based on the specific type, grade, and usage scenario. During design, national standards should be strictly followed, and appropriate specifications should be selected according to actual load requirements. At the same time, long-term overloading should be avoided to ensure structural safety.