Jet Grouting

High-pressure soil treatment technology for in-situ ground improvement, cut-off walls and structural underpinning.

Overview

Jet Grouting is a ground improvement and soil treatment technology based on the injection of high-pressure cementitious grout through specially designed nozzles. The high-energy jet erodes, mixes and replaces the in-situ soil, creating cylindrical or panel-shaped soil-cement bodies with enhanced mechanical and hydraulic properties.

This method is suitable for a wide range of soils, including clays, silts, sands and heterogeneous deposits. By modifying the in-situ ground without large-scale excavation, Jet Grouting provides increased strength, reduced permeability and improved overall stability.

Depending on project requirements and soil conditions, the system can be executed as:

Single-fluid systems
Double-fluid systems
Triple-fluid systems

Jet Grouting is widely used for underpinning existing foundations, excavation support, bottom plugs, cut-off walls and liquefaction mitigation in complex urban and infrastructure projects.

How it works?

Machine positioning and drilling start

The drilling rig is positioned and advances a drill rod to the required depth.

High-pressure injection phase

Cementitious grout is injected at very high pressure through nozzles located near the drill bit.

Soil erosion and mixing

The jet energy disaggregates the soil and simultaneously mixes it with the grout, forming a homogeneous soil-cement column.

Controlled extraction and column formation

The drill rod is gradually withdrawn while rotating, ensuring uniform geometry and strength of the treated element.

Curing and strength development

The treated soil mass hardens over time, achieving the designed structural and hydraulic performance.

Advantages

✓ Applicable to a wide range of soil types
✓ Increases strength and reduces permeability
✓ Minimal vibration and disturbance
✓ Suitable for confined and urban environments
✓ Highly versatile for underpinning and excavation support

Limitations

⚠ Execution quality depends on strict parameter control
⚠ Spoil management required for excess grout-soil mixture
⚠ Performance varies depending on soil homogeneity
⚠ Requires curing time before full load activation
⚠ Ground treatment geometry and strength can be difficult to predict in highly heterogeneous soils