The Cement-Fly Ash-Gravel Pile, or CFG Pile, was developed as an improvement over traditional stone columns. Stone columns are often unreliable in soft soil conditions due to their relatively low confinement resistance. By combining cement, fly ash, and gravel, the resulting CFG column provides a rigid foundation, making it suitable for most soil conditions. Lean concrete with a low grade (K50) to middle grade (K300) is widely used in CFG pile applications.
CFG piles can be applied in various soil conditions, including peat soil, soft clay, fat clay,
sandy soil, and complicated layered soil, as well as hard soil conditions. They can be produced
using different material combinations, such as cement-fly ash-gravel, cement-lime-gravel, and cement-sandy
(mortar).
The bearing capacity of a CFG composite foundation can be adjusted over a wide range to
meet specific engineering requirements. It can vary from low stiffness columns (similar to deep
cement mixing columns, DCM) to high stiffness columns (comparable to spun piles).The construction of CFG piles is typically fast and cost-effective, making them an attractive solution for foundation treatment in a wide variety of projects.
