Stone Column (Vibro-replacement) is a combination of vibroflotation with a gravel backfill resulting in stone columns, which not only increases the amount of densification, but provides a degree of reinforcement and a potentially effective means of drainage. Stone columns have been widely used worldwide for several decades. Most design methods for granular columns were developed based on stone columns. The columns installed by vibro-replacement (also called the wet method) are commonly referred to as stone columns or granular piles. During the tamping process, there is some degree of displacement toward the surrounding soil. There are 2 types of stone column installation method :
- Wet Method
- Dry Method
Wet method stone column use water pressure flow through the probe to vibro-replace the soil before the granular fill material is supplied through a feeding tube and form a “stone column”. Dry method stone column is similar to wet method but instead of water, air is used to help the penetration of the probe and maintain the stability of the hole.