Pile foundation systems either consist of single piles (monopiles) or a group of piles which are connected to each other by a pile cap structure. Micropiles are typically used for underpinning civil structures, especially under limited space conditions or time constraints. By definition, micropiles consist of tubular steel elements with an outer diameter range of approx. 60 - 200 [mm] (2.5 - 8.0 [in]). In general, micropiles act as a passive foundation system.
DSI micropiles are installed selfdrilling, typically using a large-diameter drill bit. Installation is accomplished with rotary or rotary-percussive drilling equipment, depending on the ground conditions and intended installation length. Filling/grouting of the borehole is either performed simultaneously while drilling or afterwards. The grout serves as bonding medium which transfers the forces to the soil in terms of skin friction. A larger grout coverage also enhances the corrosion protection of the system.