TBM first for Australian coal seam access 06 Nov 2013
Peter Kenyon, TunnelTalk
- TBM technology is being used for the first time in Australia for excavation of a coal drift. Launch of the 8m diameter Robbins EPBM at the Anglo-American owned longwall Grosvenor Mine in Central Queensland for excavation of two 1.1km-long drift tunnels could herald further application of TBMs on other projects owned by the Australian mining giant.
8m Robbins EPBM makes Australian mining history
- "We can potentially use this TBM for our future projects - we have another longwall mine in our project pipeline: Moranbah South," Jacqui Strambi of Anglo-American told TunnelTalk from Australia.
- The machine, procured from Robbins at a cost of Aust$40 million, is recently launched on the first drive. Designed by engineering and planning consultant GHD, the tunnels feature a completed i.d. of 7m and will be segmentally lined. A steep inclination of 12.5% is specified to enable quicker and shorter access to the coal seam 160m below the surface.
- After the first drift tunnel is completed, the TBM will be disassembled and extracted, leaving the shield in place. It will then be reset in a new shield for the second drive. Once both tunnels are complete, the TBM components will be retained for use on other Anglo American projects. The first tunnel will house the conveyor system while the second will be used to transport personnel and equipment into the mine.
- "This project is very important and exciting for our team," said GHD Global Technical Leader (Energy and Resources) Richard Fechner. "We are providing a range of services from geotechnical investigations and detailed tunnel design, to reviewing the TBM specification, launch and excavation methodologies, and EPB operating pressures. This will enable Anglo American to access the coal seam in a fraction of the time a traditionally excavated drift would take and provide a maintenance-free access tunnel structure for the life of the mine, expected to be 40 years." GHD has been involved in the design of a number of Australian civil tunneling projects including Legacy Way in Brisbane, the Melbourne main sewer and Epping-Chatswood tunnel in Sydney.
EPBM at Grosvenor Mine site in Australia
- The more tradition excavation approach for the mining industry is to use road headers, but drifts constructed in this way traditionally have only a 10-year lifespan before the support structure needs rehabilitation.
- Contractor Redpath Australia, which is responsible for TBM procurement and assembly and will assist a specialist Robbins operational team for the drives, said TBM excavation technology offered a safer, quicker and more reliable excavation methodology. "The tunnel boring machine is expected to excavate drifts at least three times faster than a road header, which provides much quicker access to the coal," said Gavin Ramage, Redpath General Manager of Coal.
- "There are also a number of safety benefits associated with using the TBM, mainly from the highly stable and durable ground support required, which has a 50-year life expectancy, as opposed to the less stable support used for a road header," he added.
- Grosvenor Mine Site Manager, Greg O'Donnell, said: "I would like to make special mention of Robbins for building and operating the TBM, Redpath Australia for assembling, commissioning and supporting the TBM mining, GHD for their assistance with the geotechnical engineering, Hutchinson Contractors for their civil work around this area and Hatch for providing general engineering procurement construction management (EPCM) support at site."
- Anglo American's Head of Underground Excellence, Dieter Haage, officially launched the TBM and said this was an important milestone in the overall delivery of the Aust$1.95 billion Grosvenor Mine project, which is located next to the company's existing Moranbah North longwall mine.
- "Targeting the same Goonyella Middle Seam as our Moranbah North operation, Grosvenor will be a world class longwall mine and its delivery is a key part of our growth planned in Moranbah," said Haage. "It is exciting to reach this milestone today after almost a year-and-a-half of construction activity. The EPBM will allow us to reach the coal seam early next year, bringing us that step closer to longwall production in late 2016."
Final breakthrough for Brisbane traffic link - TunnelTalk, June 2013
In situ concrete lining on a steep slope - TunnelTalk, September 2013
Add your comment
- Thank you for taking the time to share your thoughts and comments. You share in the wider tunnelling community, so please keep your comments smart and civil. Don't attack other readers personally, and keep your language professional.