Prefabricated Piles for Houses

Prefabricated piles for houses are pile foundation materials pre-made in factories or construction sites, characterized by high load-bearing capacity and fast construction speed, and are widely used in construction projects.

Types and Characteristics

The main types of prefabricated piles include solid concrete square piles, prestressed concrete pipe piles, and steel piles. Their core advantages lie in their high load-bearing capacity, enabling them to withstand significant loads while being sturdy and durable. Their construction efficiency is notably superior to that of cast-in-place piles. For example, prestressed concrete pipe piles, formed through centrifugal molding, exhibit high concrete density and excellent flexural and shear resistance. Steel piles are suitable for special geological conditions or projects with extremely high construction speed requirements.

Manufacturing Process

The manufacturing process strictly adheres to standardized steps:

1. Skeleton Assembly: Form a basic skeleton by assembling straightened and cut steel bars, wrap them with fine wire, weld them firmly, and install joint bases.
2. Mold Assembly: Place the skeleton into a mold coated with a release agent, pour concrete, manually trim the edges, close the other half of the mold, and tighten the screws.
3. Molding and Curing: Use a centrifuge to densify the concrete, cure it for a certain period, and then transfer it to an autoclave to increase strength and prevent cracking through high temperature and pressure.
4. Finished Product Treatment: After demolding, paint the joints blue, apply codes to the pile body for traceability, and finally transport it to the construction site for use.
   Key Parameters: The length of piles made on-site should not exceed 30 meters, while those made in factories should not exceed 12 meters. In terms of concrete strength, solid piles should be no less than C30, and pipe piles should be no less than C40.

Construction Methods and Procedures

Construction methods include hammering, static pressing, and vibration methods, with the core procedures being:

1. Pile Driver Positioning: Ensure the equipment is stable with a vertical deviation of ≤0.5%.
2. Pile Lifting and Stabilization: Use lifting equipment to vertically lift the pile and slowly lower it to the designed position.
3. Pile Driving and Jointing: Select the pile driving method based on geological conditions. When jointing piles, ensure the axes of the upper and lower sections are aligned, and the pile spacing is ≥3 times the pile diameter.
   Pile Driving Sequence should be flexibly adjusted according to project characteristics:

• Expanding from the center to the surroundings: Suitable for dense pile foundations, large sites, and soft soil strata.
• Advancing from one side to the other: Suitable for narrow sites or projects with obstacles on one side.
• Zonal skipping driving: Suitable for ultra-dense pile groups, soft soil foundations, or projects with strict requirements for the impact on the surrounding environment.

Industry Status and Development

China's prefabricated pile industry began with the production of RC piles in 1944 and rapidly developed after introducing Japanese PHC pile technology in the 1980s. In 2024, production reached 423 million meters, with enterprises concentrated in South China, the Yangtze River Delta, and the Bohai Rim regions. Jianhua Construction Materials and Sanhe Pipe Piles are industry representatives. The national 14th Five-Year Plan explicitly supports industry development, and the municipal quality supervision station implements full-process quality traceability through a "one pile, one code" system. Future technological directions focus on the research and development of automated production equipment and green transformation to enhance efficiency and reduce environmental impact.