First breakthrough in the twin bore Docklands Light Railway (DLR) extension to Woolwich, London, was achieved late December by AMEC using a 6.1m diameter Lovat EPB machine.
The 1.83km drive south under the River Thames in east London saw the TBM cut through chalk with some alluvium and terrace gravel early in the drive and bore out of Thanet Sands towards the end. The segmental concrete lining has 5.3m i.d. in an eight piece ring.
Work is underway to dismantle and remove the soft ground TBM. The machine will be moved back to the north side of the river for re-launch around early March to drive the second tube.
Amec is part of the consortium that won the 30-year concession to build the 2.5km long twin bore extension from King George V station to Woolwich (T&TI, July 2005, p10), scheduled for completion in 2009.
Separately, another Lovat TBM has completed boring a sewer tunnel in Milwaukee, Wisconsin. The breakthrough completed excavation on the Metropolitan Interceptor Sewer (MIS) System’s Menomenee River Special Tunnel Project.
The 101” diameter machine was skinned up to 2.6m diameter for the drive and bored three runs of 325m, 240m and 134m, respectively.
