Subsurface Grouting

Injection of cement grout into the soil beneath an existing building can be an effective method for stopping or reversing settlement caused by loose soils. Once a target zone is identified, placement of grout is completed through a series of perforated pipes, with the grout pumped under pressure into the pipes in a predetermined sequence.

Injection pressure and flow rate are determined by GAIA in collaboration with Golder, and are monitored in real time against predefined criteria to determine when each hole is sufficiently grouted. Building elevations are also monitored in real time to gauge the response to the grouting program.

Usually, after primary grouting is complete, “secondary” holes are installed and grouted in the same manner to ensure good distribution of the grout in the subsurface.