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 accurately 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)

 

BF1

 

Installation

The stones are introduced via a tremie pipe along the vibroflot and the aid of pressurized air.

 

BF2

Completion

The vibroflot is moved up and down repeatedly 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.

BF3