How to Repair Under a Container House

The repair of the area under a container house requires targeted methods based on specific issues, with common repair directions including foundation reinforcement, support adjustment, structural reinforcement, drainage optimization, and floor repair, with specific operations as follows:

1. Foundation Reinforcement
If there is subsidence or soft foundation under the container house, priority should be given to addressing the foundation problem. First, excavate the soft soil layer in the subsided area and pour concrete with a strength not lower than C20 (thickness 15-20cm). The coverage should extend at least 30cm beyond the edge of the container to ensure uniform load distribution. For surface debris or loose soil, thoroughly clean it and then fill it with crushed stones and compact it to improve soil density. If the foundation is on a slope, excavate drainage slopes or set up diversion channels to prevent rainwater accumulation and secondary subsidence.

2. Adjusting Pads and Supports
The stability of the container's bottom support system directly affects the overall structural safety. If damaged pads are found, replace them with adjustable screw feet (each with a load capacity of ≥5 tons) and adjust the height by rotation to restore the container to a level state. At the same time, check if the corner bolts are loose and tighten them to a standard value of 450-500N·m using a torque wrench to prevent structural deformation caused by loose connections. If the container has a large span or high load, additional bottom support columns can be installed in the middle to disperse local pressure and enhance overall stability.

3. Structural Reinforcement
For cases of deformation or severe subsidence of the container's bottom, structural reinforcement is required. If the deformation is slight, weld channel steel or H-shaped steel (such as 100mm×50mm specifications) inside the container to increase section stiffness and enhance bottom resistance to deformation; if the deformation is severe, first use a 10-ton hydraulic jack to lift the container to a safe height, repair the foundation simultaneously, and then reset it. In addition, reinforcement plates such as steel plates or wooden boards can be laid at the bottom to disperse local loads and prevent secondary damage caused by concentrated forces.

4. Improving Drainage System
Accumulated water is a common cause of foundation damage to container houses. Excavate drainage ditches (width ≥30cm, slope 1%-2%) around the foundation to guide rainwater away from the house; if groundwater infiltration is severe, lay a waterproof membrane with a thickness of ≥0.5mm to block moisture from infiltrating the foundation. For containers in a long-term humid environment, regularly check if the drainage system is blocked to ensure smooth drainage.

5. Floor Repair
If the problem stems from floor damage or deformation of the bottom crossbeams, dismantle the floor to check the state of the bottom crossbeams. If the crossbeams are bent, restore their straightness through mechanical correction; if the floor is severely damaged, replace it directly with corrosion-resistant, high-strength materials (such as moisture-proof wooden boards or composite floors) and lay hard materials (such as rubber pads or steel plates) under the floor to reduce wear caused by foot traffic.

6. Professional Inspection and Maintenance
Regular monitoring is key to preventing problems. It is recommended to use a level to check the subsidence of the container at least once a year (allowable error ≤3mm/m), and take timely action if abnormalities are found. For container houses that have been in use for more than 5 years or have been carrying heavy loads for a long time, contact a structural engineer for a safety assessment and develop a repair or reinforcement plan based on the assessment results to ensure long-term safe use.