Advantages of the Bottom Feed Stone Column Method
- The flow of stones to the column is mechanically controlled and
automatically recorded. - The material volumes installed can be doubtlessly allocated to precise
depth levels. - Minimal soil is transported to
the surface, which results in a lower stone consumption, since the necessary lateral confining pressure around the stone column can be reached with less gravel. - No mud handling is necessary on the site.
- Surface loss of gravel is reduced to a maximum of 2%, compared to
around 5% for the wet method.
Installation Method
Penetration
The vibroflot penetrates with the help of vibration and air flushing.
Sometimes minimal water lubrication is useful to overcome high friction from the soils)
Installation
The stones are introduced via a tremie pipe along the vibroflot and the aid of pressurized air.
Completion
The vibroflot is frequently moved up and down in order to form and compact a column. Thereby, the surrounding ground is horizontally compressed and improved. The column is able to support high vertical loads.
