Compaction grouting is a ground improvement technique involving the precision injection of a low slump, mortar grout to consolidate loose, granular soils and stabilise sinkholes or subsurface voids.
What is compaction grouting commonly used for?
Compaction grouting is used to stabilise and densify comprisable soils, loose or collapsed strata and rubble fills to increase bearing capacity and stabilize sinkholes and subsurface voids. The density of the soil is increased by injecting a stiff mortar under pressure through cased boreholes across the treatment area.
The degree of densification depends on the type of soil treated, secondary and tertiary treatment boreholes might be required to increase effectiveness.
Compaction grouting can also be carried out from an existing basement or locations with limited headroom, and it is possible to drill through hard material to reach the low strength strata beneath for treatment.
What are the advantages of Compaction Grouting?
- More cost effective than traditional methods such as removal and replacement or piling
- Treatment can be carried out within existing basement or locations with restricted access
- Capability to drill through dense layers to treat low strength strata at depth
Common Uses
- Decrease or correct settlement
- Increase bearing capacity
- Stabilise sinkholes or subsurface voids
- Suitable for rubble fills, poorly placed fills, loosened or collapsible soils, soluble rocks and liquefiable soils
- Used to treat solution features
