Square Tube Sizes for Container Houses

The commonly used square tube sizes for container houses range from 40mm×40mm to 100mm×100mm, with specific sizes determined by load-bearing requirements, structural design, and usage scenarios. The following provides an in-depth explanation from the perspectives of structural types, selection criteria, industry standards, and common model parameters:

I. Classification by Structural Type

1. Main Frame (Columns, Beams):
   As the core load-bearing structure of container houses, the main frame typically employs galvanized square tubes measuring 60mm×60mm or 80mm×80mm, with wall thicknesses ranging from 1.5-3mm. For instance, a single-story standard container house often uses 60mm×60mm square tubes with a 2mm wall thickness to meet daily load-bearing needs. For multi-story structures or those requiring heavy equipment support (such as industrial container houses), upgrading to 80mm×80mm or even 100mm×100mm square tubes with a wall thickness increased to 3mm enhances resistance to deformation.

2. Auxiliary Structures (Door and Window Frames, Partitions):
   Non-load-bearing components like door and window frames and internal partitions can utilize 40mm×40mm or 50mm×50mm square tubes with wall thicknesses of 1.2-2mm. These structures have lower strength requirements, prioritizing cost-effectiveness and lightweight design.

II. Core Selection Criteria

1. Load-Bearing Requirements:
   For single-story container houses used solely for temporary office or living purposes, 60mm×60mm square tubes suffice. If used for storing goods or as industrial warehouses, square tubes larger than 80mm×100mm should be selected based on cargo weight. For example, when carrying 2 tons per square meter of cargo, it is recommended to use 80mm×80mm square tubes for the main frame with a wall thickness of at least 2.5mm.

2. Seismic and Wind Resistance:
   In high-wind pressure areas (such as coastal regions) or earthquake-prone zones, increasing the wall thickness of square tubes to ≥2.5mm or selecting high-strength steel (such as Q345) is necessary. For instance, in areas with a seismic intensity of 8, the wall thickness of square tubes in the main frame should be no less than 3mm to enhance structural toughness.

3. Cost Balance:
   The size of square tubes is positively correlated with material costs. For example, the price of a 100mm×100mm square tube is approximately 2-3 times that of a 50mm×50mm square tube, necessitating a comprehensive evaluation based on budget and safety considerations.

III. Industry Standards and Specifications

1. Material Standards:
   Domestically, Q235 or Q345 steel is recommended, with yield strengths of at least 235MPa (Q235) or 345MPa (Q345). For international maritime container houses, compliance with CSC certification is required, and square tube sizes must pass third-party load tests to ensure structural stability during transportation.

2. Common Model Parameters:

   • 50mm×50mm: Cross-sectional area of 6.51cm², wall thickness of 2.5mm, suitable for lightweight partitions;
   • 60mm×60mm: Cross-sectional area of 9.14cm², wall thickness of 3.5mm, commonly used for single-story main frames;
   • 80mm×80mm: Cross-sectional area of 16.61cm², wall thickness of 3.0mm, suitable for multi-story or heavy-duty structures;
   • 100mm×100mm: Cross-sectional area of 25.12cm², wall thickness of 3.0mm, used for extreme load-bearing scenarios.

IV. Adjustments for Special Scenarios
If a container house needs to be converted into a mobile unit (such as a trailer house), it is recommended to use 75mm×75mm square tubes for the main frame with a wall thickness of 3.0mm to balance strength and lightweight requirements. For permanent buildings, further optimization of square tube sizes and connection methods can be made by referring to the Steel Structure Design Standard (GB 50017-2017).