By ashleykaren
Excavation work is currently taking place on the cut and cover sections of the Silvertown Tunnel in east London.
As reported, the work on the tunnel’s south entrance on the Greenwich peninsula has really picked up since the arrival of the tunnel boring machine (TBM) named Jill earlier this year.
Apparently, the TBM has rotated around inside a 40m chamber before being relaunched this spring for its journey back under the river to the Silvertown site in Newham.
A temporary pedestrian bridge has been erected over Millennium Way to facilitate the excavation of the cut-and-cover tunnel. The tunnel operates between the south portal and the TBM chamber, and Sheet Piling UK has constructed temporary bracing supports to allow the cut and cover section’s excavation.
Piling works and the construction of abutments were necessary for installing the bridge structure.
Presently, one concrete wall and 50% of the ground beams have been completed at the tunnel’s south entrance.
Sheet Piling UK has been working hard to install piles at the Silvertown location on the north side of the River Thames.
Reports say that the ground conditions near the river have been challenging, with a mix of London Clay, alluvium, and the Lambeth Group making things difficult for the subcontractor.
To overcome these obstacles, the company has had to do some pre-auguring of the pile line so that the sheet pile installation can be successful.
Sheet Piling UK has been employing its ABI TM20 long-reach telescopic leader rig to carry out the tricky sheet piling works. This rig is special because it can install further back from the pile line than other rigs in the market.
“This can deliver significant cost savings to projects, by avoiding the necessity of enabling works, required solely for a standard rig to reach a pile installation line,” the company described.
“Throughout the many months that we have been involved with the project, we have utilized construction plant from our own in-house fleet, with this offering firm assurances over NRMM [non-road mobile machinery] compliance and health and safety testing, as well as avoiding any delays for the client.”
Riverlinx CJV is delivering the Silvertown Tunnel scheme in east London. The joint venture is contracted by Transport for London and Riverlinx, which incorporates three civil engineering and construction companies; Bam Nuttall, Ferrovial Construction, and SK Ecoplant.
The Silvertown Tunnel is a 1.4km twin-bore road tunnel that is said to connect Newham to the Greenwich Peninsula when it opens in 2025. The second bore is expected to be finished by the end of summer 2023.
