Transport for London (TfL) has announced that the contractor working on the construction of the Silvertown Tunnel has completed the course of its first tunnel boring machine (TBM) bore in Greenwich.
The news comes just one day after documents from TfL’s upcoming Program and Investment Committee meeting revealed that the road tunnel project under the Thames in east London has incurred £1m of additional costs since December. and delivery is expected to be delayed.
Despite warnings, design-build-maintain-finance contractor Riverlinx, a joint venture of Bam Nuttall, Ferrovial Construction and SK Ecoplant, has reached the plan’s main milestone ahead of schedule. The early stages of tunnel excavation work were briefly halted after a fire in the debris conveying system prompted an industry-wide advisory to be issued.
The arrival of the TBM in Greenwich after 1.1km from Silvertown on the north side of the Thames triggers the start of a new engineering challenge for the Riverlinx team. The TBM’s cutting head entered a 40m diameter spindle in Greenwich and the team will now begin rotating the machine section by section within the chamber, ready to relaunch the TBM for a second trip back to Silvertown. .
The project team said NCE As of late last year, there is only “millimeters of clearance” for the rotating process, which will use “nitrogen skids” in the UK for the first time to help lift and move each part of the TBM.
Once excavation resumes, waste from the second tunnel will be fed back through the conveyor systems installed within the first tunnel to allow it to also be removed by barge from the Newham site. The second drilling is expected to be completed in late summer 2023.
Riverlinx project manager Juan Ángel Martínez described the solutions being used for the project as “firsts for the UK market”.
TfL’s Silvertown Tunnel program manager, Helen Wright, said: “The completion of the first bore of the Silvertown Tunnel is a huge milestone for the project. Work is now underway to rotate the TBM within the rotation chamber, which is an innovative and complex process so excavation of the second tunnel can begin in the coming weeks We are committed to working hard to ensure this project is delivered with minimal impact to those who live, work and visit the local area and we have extensive monitoring to ensure this continues to be the case during and after construction.”
Work on the project extends beyond the tunnel sections powered by TBM and TfL has said Riverlinx is making good progress on building the cut and covered tunnels that will bring the route to ground level before it connects. with local road networks at either end. .
In conjunction with the construction of the tunnel, TfL and Riverlinx are also actively working on designs for the walking, cycling and landscaping improvements, which will be delivered to either side of the tunnel entrances. These will see new dedicated cycle lanes and pavements, as well as ‘shared space’ and a new public realm installed at the Tidal Basin Road roundabout, which will link up with wider improvements planned by Newham Council in the Royal Docks area. Proposed landscaping around the tunnel entrances, as well as a green roof on the two tunnel portal buildings, will also form part of the plan’s commitment to environmental improvements and the promotion of biodiversity in the wider area.
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