John Holland (TBM Grout Plant)



John Holland Group
Melbourne Main Sewer Replacement Project
Melbourne, Australia

20 m3/hr



  • Conceptual Design
  • Mechanical Engineering
  • Fabrication of all Equipment
  • Commissioning
  • On-Site Training & Site-Support
  • Grout Mix Design Testing


  • SD1200 Colloidal Mixer
  • 3000 litre Agitation Tank
  • Heavy Duty Framed Skid
  • Automated PLC/MCC Control System
  • Water Feed 6×5 Centrifugal Pump
  • Admixture Dosing System
  • Pneumatic System
  • Moyno Progressive Cavity Grout Pump
  • Flow and Pressure Instrumentation

The original Melbourne main sewer was built between 1894 and 1897. Due to its age and lack of capacity for current urban growth, the old sewer line was replaced under a contract awarded to the John Holland Group, effectively tripling the existing capacity. The 2.2 km segmentally lined tunnel was built using a Lovat EPB machine with a cutting diameter of 2.95m. The final lining was a 1.8 m diameter glass reinforced plastic pipe which had to be back grouted inside the tunnel.

To back grout the lining it was critically important to maintain precise control of the grout pump pressures inside the tunnel to prevent damage to plastic pipe itself. Furthermore, this operation required a significantly higher grout production rate than the TBM boring operations so the contractor was unable to use its existing bi-component TBM grout plant. Team Mixing was contracted to provide a suitable grout plant. Although the final plant was designed to fit within a high cube shipping container, the plant was flown to site to meet tight project timelines.