西部港湾隧道项目正利用两台南半球最大的隧道掘进机在悉尼港下进行挖掘作业[1]。这一价值74亿澳元的高速公路项目已完成一半以上，两台机器预计在4月至6月间突破到北岸接收室[1]。整条隧道定于2028年末开放[1]。
名为Barangaroo的隧道掘进机长137米、重4400吨，正在伯奇格罗夫下方挖掘1.5公里的隧道[1]。两台机器的切割直径均为15.71米，每条隧道宽度接近16米，足以容纳三条地铁隧道[1]。西部港湾隧道项目的孪生隧道总长6.5公里[1]。
工程面临的最大挑战是港口下200米的古老河床区域，该区域由粘土、淤泥和沙组成[1]。每台机器预计需要约6周时间通过这一最危险的古河床区域[1]。项目每天约需120辆卡车运送从伯奇格罗夫下方挖出的弃土[1]，任何时刻有最多600人在地下从事相关工作[1]。
Two massive tunnel boring machines are carving twin tunnels beneath Sydney Harbour as part of the A$7.4 billion Western Harbour Tunnel project, with operations more than halfway complete.[1] The Barangaroo machine, measuring 137 metres long and weighing 4,400 tonnes, is excavating a 1.5-kilometre stretch beneath Birchgrove, with each tunnel reaching nearly 16 metres in width—wide enough to accommodate three subway tunnels.[1] The two TBMs, the largest in the Southern Hemisphere with a cutting diameter of 15.71 metres, are expected to break through to the northern shore reception chamber between April and June, with the complete 6.5-kilometre tunnel system scheduled to open by the end of 2028.[1]
The most perilous phase of construction involves navigating a 200-metre-deep ancient riverbed, or paleo channel, composed of clay, silt, and sand beneath the harbour.[1] Each machine is anticipated to require approximately six weeks to traverse this treacherous zone.[1] The excavation operation is intensive, with approximately 120 truck loads of spoil transported daily from beneath Birchgrove, and as many as 600 workers present underground at any given time.[1]