Container House Floor Repair

The repair of the floor of a container house requires targeted solutions based on the floor material and the extent of damage, with core steps including damage assessment, material selection, repair implementation, and quality inspection.

I. Damage Assessment and Cause Analysis
Common types of damage to container floors include:

1. Surface Wear: Long-term weight-bearing or friction causes the surface plywood layer to detach, commonly seen in logistics containers and yard storage units.
2. Structural Deformation: Overloading or external impact causes the floor to bend, possibly accompanied by deformation of the steel frame.
3. Decay/Mold: Wooden floors are subject to fungal erosion in humid environments, often found in areas without waterproofing treatment.
4. Connector Failure: Loose or corroded fixing bolts between the floor and the steel frame reduce overall stability.
   A comprehensive assessment of the damage level is required through visual inspection, tapping tests (to detect hollow areas), and load-bearing tests (simulating heavy object placement).

II. Material Selection and Suitability
Select repair materials based on the usage scenario:

1. Wooden Floors: Prioritize the use of keruing plywood (e.g., the 2400×1160×28mm specification produced by Guangzhou Guotian), which offers better wear resistance and bonding strength than ordinary poplar wood and complies with international container standards (e.g., ISO 668).
2. Steel Floors: Use Q235 steel plates (thickness ≥3mm) with anti-rust treatment (e.g., hot-dip galvanizing or epoxy coating).
3. Composite Materials: Magnesium oxide boards (Class A1 fire resistance) or fiber cement boards are suitable for scenarios with high fire and moisture resistance requirements, but their brittleness should be noted.
   Key Parameters: The load-bearing capacity of the material must be ≥120% of the original design value, e.g., the static load of a standard shipping container floor must reach 5460kg/m².

III. Repair Implementation Process

1. Pre-treatment:
   • Remove dirt and rust from the floor surface; for wooden floors, ensure thorough drying (moisture content ≤14%).
   • Hydraulically correct deformed steel frames to ensure a flatness error ≤3mm/m.
2. Local Repair:
   • Wooden Floors: Cut out the damaged area (with a 45° bevel at the edges), insert a patch of the same material, bond it with high-strength structural adhesive (e.g., epoxy resin), and secure it with stainless steel self-tapping screws (spacing ≤150mm).
   • Steel Floors: Repair cracks using CO₂ gas shielded welding, with the welds undergoing ultrasonic flaw detection.
3. Overall Reinforcement:
   • Add reinforcing ribs (e.g., L50×5 angle steel) at the connection between the floor and the steel frame, fixed with M12 high-strength bolts.
   • For frequently moved containers, spray polyurea elastomer (thickness ≥2mm) on the floor surface to enhance wear resistance.

IV. Quality Inspection Standards

1. Visual Inspection: The repaired area should have no obvious color differences or burrs, with uniform and full welds.
2. Performance Testing:
   • Load Test: Apply 1.5 times the rated load (e.g., a 20-foot container requires a static load test of 30 tons) for 24 hours, with no permanent deformation.
   • Waterproof Test: Simulate rainfall (200mm/h intensity for 1 hour) on wooden floors, with no leakage inside.
3. Documentation: Keep material certificates, welding procedure qualification reports, and test data for future maintenance reference.

V. Preventive Maintenance Recommendations

1. Regularly check that the floor drainage holes are unobstructed to prevent water accumulation and decay.
2. In humid areas, apply tung oil or water-based preservatives to wooden floors every 2 years.
3. Avoid long-term eccentric loading of containers (with a single-side load difference ≤10%) to reduce structural stress concentration.