TOP FEED METHOD
Stone columns "Top Feed Method" is the most cost-efficient ground improvement method. It requires the use of a free hanging vibrolance that penetrates the ground thanks to the lateral vibrations emitted by its tip. During penetration, the soil is laterally compacted by displacement, allowing the vibrolance to create the hole that will contain the stone column.
When the desired depth is reached, the vibrolance is withdrawn to allow the stones to be released from the ground surface into the hole. The stone feeding is done by stages to allow a better compaction of the entire stone column.Each time the hole is filled with stones, the vibrolance goes down again to compact them. This process is repeated several times until the stones reach the surface.
BOTTOM-FEED SYSTEM
The BFS system controls the length and the diameter of the stone column, better than the Top feed system. In addition, there is no risk of soil collapse while the stone is released, because the Vibrolance is not withdrawn from the ground until the stone column is finished.
Thus, the BFS system allows the contractor to have a continuous production process that results in higher productivity and time savings.
