Reinforcement of Prefabricated Square Piles for Buildings

For the reinforcement of prefabricated square piles in buildings, the anchor static pressure pile method can be adopted. Although the driven pile method is theoretically feasible, its application in building reinforcement is not clearly mentioned, and the anchor static pressure pile method is commonly used.

Principle of the Anchor Static Pressure Pile Method

The anchor static pressure pile method utilizes the building's own weight as counterforce. By excavating or pre-reserving pile-pressing holes in the foundation, prefabricated piles are pressed into the soil segment by segment. Then, the piles are connected to the foundation as a whole, enabling the piles to bear part of the upper structural load and achieve the purpose of foundation reinforcement. This method is suitable for various soft soil foundations, such as silt, silty soil, cohesive soil, and silt soil, and has a significant effect on reinforcing the foundation settlement of existing buildings.

Key Points of Construction for the Anchor Static Pressure Pile Method

1. Foundation Treatment: Before pile pressing, the foundation surface should be cleaned and leveled. This ensures the smooth installation of anchors and piles. If the foundation surface is uneven or contains debris, it will affect the fixation of anchors and the pressing of piles, thereby impacting the quality of the entire reinforcement project.
2. Anchor Installation: Drill holes in the foundation according to design requirements, insert anchors, and fix them firmly. The specifications, lengths, and spacings of anchors must strictly comply with design requirements, as anchors are crucial components for transferring pressure and fixing piles. The accuracy of their parameters directly affects the connection effect between piles and the foundation and the stability of reinforcement.
3. Pile Segment Pressing: Lift the prefabricated piles to the pile positions and apply pressure through anchors to press the piles into the soil segment by segment. During pile pressing, special attention should be paid to controlling the verticality of the piles, and the deviation should not be too large. If the verticality deviation of the piles is too large, it will lead to uneven stress on the piles, affecting their bearing capacity and even preventing the piles from functioning properly in reinforcement.
4. Connection between Piles and Foundation: After the piles are pressed to the designed depth, connect the piles to the foundation firmly using welding or other reliable methods. This step is crucial for ensuring the smooth transfer of loads. Only when the piles are firmly connected to the foundation can they effectively bear the upper structural loads and achieve the purpose of foundation reinforcement.