Compaction grouting is a process that improves the bearing capacity of foundations and underlying soils by pumping a low-slump cement mixture into the soil, under pressure.

The cement pushes aside the surrounding soil as it is pumped in, compacting the soil in the process and increasing its density, while forming a grout column or bulb. The method is thus simple in essence but requires careful planning based on a knowledge of onsite conditions to achieve best results at a given location.