1. Positioning of the tube and forming of a plug of dry concrete to seal the bottom of the first permanent tube. Using a free-fall hammer to compact the plug that facilitates the driving of the lower tube segment into the soil.
2. Welding of the additional tube elements of limited length and continuation of the driving phase.
3. Driving to the required installation depth
4. & 5. When the required depth has been reached, additional dry concrete is poured within the slitted part of the steel tube thereby enlarging the plug, expelling it in the zone of the slots, opening the tube and forming an expanded base.
6. Placement of the reinforcement
7. Casting concrete