The Ferrovial BEMO JV will deploy the mixshield machine to build a 2.2km tunnel under the River Thames to replace the existing tunnel constructed in the 1960s.
Herrenknecht says the TBM will work in challenging geological conditions, including very strong flintstones, water pressures of up to 4.5 bar and high ground permeability.
It will connect the two shafts constructed using the largest Herrenknecht vertical shaft sinking machine (VSM) ever produced in Germany by beginning with a complex umbilical launch.
With an inner diameter of 15m, the VSM is being used to sink both the launch and reception shafts. The TBM will start in Tilbury at a depth of more than 45m and advance towards Gravesend, where it will arrive at a depth of 45m.
The final depth at the launch shaft was reached in mid-December.
The Grain to Tilbury project in Kent is part of National Grid’s Great Grid Upgrade to strengthen the UK’s energy network.
