Jet grouting involves the mixing and partial replacement of the in-situ soil with cement slurry as opposed to conventional grouting which involves the injection of cement slurry into the voids in the soil.  In its simplest form the process involves the ejection of cement slurry from a rotating grout tube, fitted with a nozzle, under very high pressure.  The jet cuts a path outwards from the grout tube in a radial direction. The eroded soil is rearranged and mixed with the cement suspension. The combination of rotation and gradual step-wise withdrawal enables a large diameter in-situ grout column to be formed in the ground.

Positive Features

  • A wide range of soil types can be treated
  • It is a vibration-less system
  • Noise levels are low and limited to engine noise only
  • It has features which provide unique solutions to difficult geotechnical problems
  • Large diameter columns of up to 4 meters can be formed in suitable ground conditions
  • Small rigs available for headroom restrictions and in confined working environments
  • Able to operate around underground installations in service

 Applications of Jet Grouting

  • Forming of grout columns to support structural loads
  • Forming a contiguous wall for a caisson or cofferdam
  • Forming a contiguous wall for lateral support
  • Forming cut-off walls for groundwater control
  • Forming a base seal to an excavation below the water-table
  • Under-pinning of foundations and quay walls
  • Sealing between piles on a contiguous pile wall construction