A grout curtain is a barrier that protects the foundation of a dam from seepage and can be made during initial construction or during repair. Additionally, they can be used to strengthen foundations and contain spills.
A grout curtain usually consists of a row of vertically drilled holes filled with pressurized grout, a process commonly known as pressure grouting. The holes are drilled in intervals and in such a way that they cross each other, creating a curtain.
Grout is injected with grouting jets, which use a high-pressure fluid stream (i.e., slurry or water) to erode a cavity in the soil.