Otway Phase Three Stabilisation

Location: Portland – Victoria, Australia

Client: Origin Energy

Contractor: SapuraClough

Scope of Work: Provision of Articulated Concrete Mattresses

Subcon was subcontracted to SapuraClough to provide them with forty 16.5 Tonne Concrete Mattresses. These mattresses were large wide matts (0.5m x 4m x 6m) making transporting them by road difficult. Subcon mobilised its fabrication crew into the Port of Portland and utilised the port authorities €™ hard stand for the fabrication of the mattresses.

This saved the client substantially in transportation costs.

Subcon was contracted by SapuraClough on behalf of operator Origin Energy for the stabilisation.


  • The SGM1000 is safer and quieter to operate and faster to mobilise
  • Dust extractors prevented exposure of cement dust to people, equipment and the environment
  • Specially designed grout mix was provided to supply a high strength product

The project utilised Subcon’s compact SGM1000 Jet Mixers. These unique skids include an integrated recirculating jet mixer, agitator tank and a monopump. Our “single skid” philosophy minimises handling, freight, seafastening, hoses on deck and electrical wiring.

The SGM1000 is safer and quieter to operate and faster to mobilise. Dust extractor on the hood of the mixer ensured that the personnel, vessel and environment were not exposed to cement dust.

A purpose grout mix designed was developed and tested in conjunction with a leading additives supplier to provide a high early strength, low shrinkage grout with high sulphate resistivity and a 28 day strength

Subcon’s preparation, safety culture, our employees’ onsite work ethic and reliable equipment meant that each phase of the project was completed ahead of schedule.