Peabody, a Brisbane-based tunnelling contractor and mining company, in JV with Japan’s Obayashi Corporation, has won a US$32 m contract from Queensland’s Brisbane Water for sewer construction in Australia. The JV will construct the 5 km long sewer through Brisbane’s CBD using two 3m diameter Robbins TBMs.
Because of variable geology,the contractor has ordered two different TBM models. A double shield machine equipped with a flat, low profile, variable speed cutterhead will bore 3.6km through the competent rock.. The remaining 1.4km length will be driven using a 3m diameter single shield machine that allows injection of foam or slurry.
The 2.5m i.d. tunnel, with an anti-corrosion liner, will be bored between 18-46m below ground and act as an overflow for the existing S1 sewer system which is 80 years old. The Peabody/ Obayashi group won the contract in early September.
The UK’s Halcrow Group designed the rock support, lining, ventilation and odour control equipment. The contractors will take extensive measures to limit the effects of construction the city.
Construction of the tunnel, which runs from North Quay to Cooksley Street, Albion, is due to finish by mid-2001.
