Soil improvement by means of stone columns results in the construction of cylindrical elements, cast-in-situ, consisting of gravel that is compacted by driving, or by using vibroflotation (vibro-compaction).
Construction sequence
Installation process of a stone column by bottom driving with an internal ram.
1. Construction of a gravel plug at the bottom of the cylindrical steel casing
2. Bottom driving on the plug using an internal ram (piston) causes the casing to be driven into the soil, down to the required founding level, and displace the surrounding soil laterally.
3. When the required installation depth of the column has been reached, expulsion of the plug with the cylindrical internal piston.
4. Realisation of the compacted stone column, formed by adding and expelling the required amount of gravel while simultaneously and gradually withdrawing the tube.
5. Completed gravel column