A combi-wall is an earth-retaining wall that, as the name suggests, is composed of different types of profiles.
First, steel tubular piles are driven into the soil. These piles are fitted with locks for inserting the sheet piles. For driving in the piles (pile driving, vibrating), a pile driving frame is used to ensure the accurate installation of the piles. Finally, the sheet piles are placed in between the tubular piles.
The main advantage of this wall is the great stiffness of the whole, which also increases its bearing strength. The combi-wall is stabilised by installing horizontal struts or anchors (e.g. MV-piles or ground anchors) in the soil behind it.