Network Rail Infrastructure is asking the industry to come up with alternative tunnelling techniques that could reduce disruption to the railways. In the request for information (RFI) notice on the Official Journal of European Union, it is asking for industry to suggest and develop with new ways to build new tunnels and maintain its existing 693 tunnels.
Network Rail wants to build tunnel infrastructure within existing geologies prior to excavation. The authority wants to trial, with the potential to implement, a method of building a tunnel structure prior to excavation.
According to Network Rail the objective would be; to reduce the cost of constructing tunnels; reduce safety risk from constructing tunnels, by removing the need for people to work within tunnels where possible; and reduce the duration of railway closures that are required using existing methods such as tunnel boring machines (TBMs).
Suppliers would need to provide a description of the system including:
- How the solution can build a new structure without removing an existing tunnel structure first.
- What materials the structure will be constructed from.
- The design life of the constructed tunnel.
- How the solution would not disturb the geology near or surrounding the existing tunnel(s).
- How you will excavate after the tunnel structure is prepared.
Timings the extent of testing required would also need to be provided, as well key risks and the environmental impact.