Container House Strip Foundation
When container houses use strip foundations, specific methods need to be determined based on the house type, geological conditions, and usage requirements. Common solutions include shallow strip foundation layouts, elevated strip foundations, and combinations with other foundation forms. The following provides an explanation from three aspects: applicable scenarios, structural characteristics, and construction key points.
1. Applicable Scenarios and House Types
Strip foundations are commonly used in container houses for packing containers and some light-duty fixed container houses. Packing container houses have flexible foundation requirements and can use strip foundations to simplify construction, especially suitable for sites with stable geological conditions and low load requirements. Foldable container houses and fixed residential container houses, although having relatively low foundation requirements, can also enhance stability through strip foundations in areas with soft geology or high drainage demands. For example, in the scenario of temporary dormitories on construction sites, if there is a risk of slight uneven settlement on the ground, strip foundations can disperse the load through continuous support and avoid local stress concentration.
2. Structural Characteristics and Material Selection
Strip foundations are usually reinforced concrete structures, and the cross-sectional dimensions need to be calculated and determined based on the total weight of the house, geological bearing capacity, and the depth of the permafrost layer. For light-duty container houses (such as single-story packing containers), the foundation width can be controlled between 0.3-0.5 meters, and the depth can be adjusted according to the soil quality; if the number of house floors increases or the geology is poor, the foundation dimensions need to be expanded or reinforced with steel bars. In terms of materials, the concrete strength grade should generally not be lower than C20, and the diameter and spacing of steel bars should meet the requirements for bending and shear calculations. In addition, connecting elements (such as steel plates or bolts) need to be embedded at the top of the strip foundation to facilitate fixation with the corner fittings or bottom frames of the container houses and ensure structural integrity.
3. Construction Key Points and Precautions
Before construction, a geological survey should be carried out to clarify the soil layer distribution, bearing capacity, and groundwater level to avoid foundation settlement or tilting. After foundation excavation, the base should be compacted, and a gravel cushion should be laid to improve the bearing capacity and reduce uneven settlement. During concrete pouring, it should be vibrated and compacted to avoid defects such as honeycombs and pockmarks; if the foundation is long, expansion joints should be set according to specifications (the spacing is usually 10-15 meters). After construction is completed, it should be cured until the design strength is reached before installing the container houses. In cold regions, the foundation burial depth should be lower than the permafrost layer to prevent frost heave damage. In addition, if there are drainage problems on the site, drainage ditches can be set on the outer side of the strip foundation to avoid water erosion of the foundation.
Special Scenario Optimization
In soft soil foundations or sloped sites, strip foundations can be used in combination with pile foundations (such as mini-piles or root piles). The piles penetrate the soft layer to reach the bearing layer, improving foundation stability. For temporary houses that require rapid assembly and disassembly, prefabricated strip foundations (such as prefabricated concrete beams or steel beams) can be used, enabling rapid installation and disassembly through bolt connections and reducing on-site wet work volume.
