Pouring of Concrete Prefabricated Houses

The pouring techniques for concrete prefabricated houses mainly fall into three categories: traditional prefabricated panels, prefabricated industrial pouring, and on-site assembly collaborative processes, each with distinct process characteristics and applicable scenarios.

1. Pouring Characteristics of Traditional Concrete Prefabricated Panel Houses
Traditional prefabricated panels are processed in advance in factories, where concrete members such as floor slabs and roof panels are formed by binding steel bars and pouring concrete on-site. The core process is panel splicing, but it has significant drawbacks:

• Limited Structural Safety: Panels are connected through splicing techniques, with relatively little steel bar usage, making the overall structure dependent on the quality of the splicing. In earthquake-prone areas, the splicing gaps can easily lead to collapse risks, such as the damage to some traditional prefabricated panel houses due to panel separation during earthquakes.
• Insufficient Functionality: Splicing gaps result in poor sound insulation, water leakage, and insulation performance that relies on additional materials, making it difficult to meet modern building requirements for comfort.
• Cost Advantage: Due to simplified materials and processes, its construction cost is lower than that of prefabricated houses, but long-term maintenance costs (such as waterproofing repairs) may offset the initial savings.

2. Industrial Pouring Techniques for Prefabricated Concrete Houses
Modern prefabricated houses adopt a full-frame shear wall structure, formed by one-time pouring in molds to create an integrated load-bearing system, with significant technical advantages:

• Modularization and High Strength: Each module uses C35 concrete and Φ8-Φ14 threaded steel bars, with a wall thickness of 150mm and a floor slab thickness of 100mm, achieving a compressive strength of 30MPa (1.5 times that of traditional brick-concrete structures), capable of withstanding higher loads.
• Integrated Design: Modules are pre-embedded with water and electricity pipelines and EPS insulation layers (thickness 50-100mm), with waterproof testing completed before leaving the factory, reducing on-site construction steps and minimizing human error risks.
• Outstanding Seismic Performance: Flexible connections are achieved through pre-stressed bolts and welded steel plates, with a single-point tensile strength of 20 tons, adaptable to seismic fortification intensities of 7-9 degrees (adjusted according to floor level). For example, during the 6.2-magnitude earthquake in Zhaotong, Yunnan in 2023, the main structure of the prefabricated house remained intact, with only a 0.1mm fine crack appearing on the wall.

3. Collaborative Process of On-Site Assembly and Pouring
The construction of prefabricated houses is centered around a "building block" model:

• Rapid Assembly: After prefabricated modules are transported to the site, assembly is completed within 3 days using lifting equipment, allowing occupancy after connecting water and electricity, shortening the construction period by more than 60% compared to traditional brick-concrete structures.
• Significant Environmental Benefits: On-site construction personnel are reduced by 70%, construction waste by 90%, and carbon emissions by 35%, aligning with green building development trends.

4. Reference for Cast-in-Place Process in Rural Self-Built Houses
If a cast-in-place process (non-prefabricated) is adopted, the following steps should be followed:

• Construction Sequence: Pour beams and columns first, then pour floor slabs to ensure structural integrity.
• Curing Requirements: Cover with film immediately after pouring to avoid cracks, start watering curing 3 hours later, with at least 5 times a day to control concrete shrinkage cracks.
  However, it should be noted that the cast-in-place process relies on on-site construction precision, with significant quality fluctuations, while prefabricated houses can better ensure performance consistency through standardized factory production.