Jet Grouting for Soil Improvement | USA Excavation Support

If you’re looking for soil improvement technology to support the stability of excavations, foundation reinforcement, and many other soil support challenges, you’ve come to the right place. We feel that jet grouting is precisely the right choice.

This article defines jet grouting, examines the process, highlights the applications, lists the many advantages, and delves into polymer-based emulsion grouting.

What Is Jet Grouting?

Jet grouting is a specialized ground improvement technique used in geotechnical engineering to create a soil-grout mixture in situ. It is typically employed to strengthen the ground, create impermeable barriers, and control ground settlement. 

What Is the Jet Grouting Process?

The process of jet grouting consists of using high-speed fluid jets to erode the soil and mix it with a cement-based grout.

The grout is injected through small nozzles at the bottom of the drilling rods. As the rods are withdrawn, it creates a column of treated soil-cement mixture in the ground. The grout used in the process can be adjusted to meet specific project requirements, such as strength, permeability, and setting time.

There are three methods of jet grouting. They are categorized by the system fluid used in the grouting process.

  • Single fluid system: In this method, a slurry grout jet is used for the erosion and mixing of in situ soil.
  • Double fluid system: This approach involves using a slurry grout jet surrounded by an air jet for enhanced soil erosion and grout mixing.
  • Triple fluid system: This method utilizes a water jet surrounded by an air jet, with a separate grout nozzle for grout mixing.
The jet grouting process using fluid jets explained with single, double, triple system methods, alongside an operational scene.

Jet Grouting Soil Improvement Applications

Jet grouting has many applications across all types of construction projects. 

  • Ground improvement: Jet grouting is used to improve the load-bearing capacity of the soil by creating a soil-cement column that increases the overall strength and stability of the ground. This is particularly useful in areas with poor soil conditions or where the soil needs reinforcement to support heavy structures.
  • Excavation support: This can be used to provide temporary or permanent excavation support during the construction of underground structures, such as tunnels, shafts, and deep basements. The treated soil-cement columns help stabilize the excavation site and prevent collapse or soil movement.
  • Sealing and waterproofing: Jet grouting effectively creates impermeable barriers to control groundwater flow and prevent seepage. This is particularly beneficial in projects where waterproofing is crucial, such as in constructing tunnels, underground structures, and basements.
  • Retaining walls: Jet grouting can be utilized to create retaining walls, especially in areas where traditional retaining wall construction is not feasible or cost-effective. The soil-cement columns created through jet grouting provide structural support and help prevent soil erosion and slope instability.
  • Foundation support: Jet grouting is employed to strengthen the foundation of structures, such as buildings, bridges, and other infrastructure projects. It can help improve the bearing capacity of the soil, reduce settlement, and mitigate the risk of foundation failure.
  • Slope stabilization: In projects involving slopes or embankments, jet grouting can be used to stabilize the soil and prevent erosion, landslides, and other potential hazards. Creating a stabilizing mixture helps maintain the integrity of the slope and prevents soil movement.
  • Foundation Reinforcement and Underpinning. Drilling through existing foundations can provide improved load distribution under the footings. This can be used to improve the load-bearing capacity of weak or loose soils. Applications include bridges, buildings, and similar structures.
Listed uses of jet grouting in soil enhancement for ground and excavation support, with workers and equipment in the background.

Advantages of Jet Grouting for Soil Improvement

Based on the lengthy list of applications above, you can surmise that there are quite a few advantages of jet grouting for soil improvement. Here’s a broad list that can be expanded to fit your construction project’s parameters. 

  • Reduced Disruption. This approach does not require trenching, uses smaller equipment, and minimizes the vibrations that can impact any surrounding structures. The process can be carried out in limited access areas, minimizing disruption to the surrounding environment and ongoing construction activities.
  • Soil Type Versatility. Jet grouting can be applied in various soil types, including cohesive soils, granular soils, and contaminated soils, making it a versatile solution for different ground conditions.
  • Improved Load-Bearing Capacity. The resulting soil-cement columns substantially improve the soil’s load-bearing capacity. 
  • Adjustments as Needed. The nature of jet grouting allows adjustment as needed to achieve the required column shape and size. This adds a great deal of control to the soil improvement process.
Key benefits of jet grouting for soil stability are listed alongside an image of workers using grouting machinery on a surface.

Grouting Material Classifications and Properties

There are three broad classifications of grouting material: particulate, emulsion, and chemical. Particulate grouts use particulate solids suspended in a fluid. That includes cement, cement-bentonite, and soil-water grouts. Emulsion grouts contain solids or liquids dispersed in water to form minute particles. Chemical grouts contain solids or liquids that react to form a hydrogel.

The critical properties of any grout include the following:

  • Viscosity. This is the property of the grout to resist deformation under stress. It also affects the ability of the grout to flow through the soil. The lower (thinner) the viscosity, the better the penetration. 
  • Gel Time. This is the time after mixing the grout and its setting into a viscous gel.
  • Particle Size. The size of the grout’s particles determines its ability to penetrate the soil. Different soils require different particle sizes.
  • Strength. The compressive strength of the grout-treated soil needs to be matched to the particular soil type and project requirements. 
  • Durability. Freezing, thawing, extreme heat, and wet and dry conditions must be accounted for when selecting the best jet grouting material. 
  • Cohesion. Maintaining integrity between the soil and grout is critical for soil stabilization in support of excavation projects.
  • Stability. This is related to durability, where the grout soil mixture must maintain its properties despite extreme environmental conditions. 
Classification of Jet grouting materials - as particulate, emulsion, and chemical, with properties like viscosity and strength.

We Can Meet Your Soil Improvement Needs in the USA

As with any ground-breaking technology, working with the experts is best. Sovereign Hydroseal was founded over 50 years ago on safety, social responsibility, and quality principles. We bring those years of experience and our deep expertise to every project.

For further information or to explore project-specific information, please use our contact form, email us at, or call us at +1 646.649.5878, and we can get started.