Compaction grouting involves the injection of a low slump, mortar grout to densify loose, granular soils and stabilise subsurface voids or sinkholes.
Process
An injection pipe is inserted, typically to maximum treatment depth, and the grout then injected as the pipe is slowly removed in lifts, creating a column of overlapping grout bulbs. The expansion of the grout bulbs displaces surrounding soils and the grouting increases the density, friction angle, and stiffness of surrounding granular soils.
You can increase effectiveness by sequencing the compaction grouting from primary to secondary to tertiary locations. In all soils, the high modulus grout column reinforces the treatment zone.
Specialist Contact | Bruce Stephenson - [email protected] - +44 (0)7918 193001
Common uses
- Suitable for rubble fills, poorly placed fills, loosened or collapsible soils, soluble rocks and liquefiable soils
- Often selected for treatment beneath existing structures because the columns do not require structural connection to the foundations
- Decrease or correct settlement
- Increase bearing capacity
- Stabilise sinkholes or reduce sinkhole potential
Advantages
- Often more economic than conventional approaches such as removal and replacement, or piling
- Can be done where access is difficult and in limited space
Quality assurance
Keller can provide complete solutions which combine compaction grouting with real-time monitoring of affected structures, and has a variety of rig types to accommodate access constraints.
Related techniques
Related solutions
Related projects
Residential
Oakapple Lane, Barming
The presence of possible solution features meant that ground improvement works on a housing site in Kent were not straightforward, especially as the site was already built-up with homes occupied. Keller's compaction grouting technique solved the problem of treating the ground with minimum disruption.
Residential
Herns Lane
An unusual treatment for a housing site which goes to prove that whatever the ground conditions, Keller has the solution.