Vertical drains are applied for ground improvement in order to consolidate soft ground.
They are suitable for very soft and soft soils with a high water content.
Prefabricated plastic drains are inserted into the ground using a custom build machine called stitcher. A regular grid of drains leads to a controlled consolidation process applying a surcharge for a certain time period. After the consolidation was completed the surcharge is removed and the building of the foundations is started.