Tunnel boring machine Victoria being lifted into the Limmo Peninsula launch shaft. Over a distance of 8.2 kilometers it drove beneath Soho, Hyde Park and some of the most expensive real estate in the world
Highspeed in London
In London eight Herrenknecht tunnel boring machines are creating a continuous rail link through the megacity. In just three years construction crews from three UK and European consortia navigated the high-tech borers from Schwanau through the center of London.
The 14.8 billion pound project is a veritable tunnel marathon: the three contracted joint ventures are building 42 kilometers in their three sections. All of them are relying on tunnel boring machines (TBMs) from Herrenknecht: six Earth Pressure Balance Shields and two Mixshields. With millimeter tolerance they are boring through the bowels of the city, a maze of sewers, gas pipelines, building foundations, subway lines and shafts. Sometimes they almost touch the existing infrastructure – in some places the distance to the Crossrail tunnels is less than half a meter.
The new railway link crossing through Britain's capital will have a total length of 118 kilometers. When operations start as scheduled in 2018, Crossrail will create a new and lastingly efficient railway route for up to 200 million passengers a year, running from Maidenhead and Heathrow in the west to Shenfield and Abbey Wood in the east. The new route will have 41 transfer points to other rail infrastructures - an attractive offer for both commuters and tourists.
Between Royal Oak in the west and Plumstead in the east, the route will cross beneath London's city center in two parallel twin tubes along a length of two times 21 kilometers. Section C310 will cross beneath the Thames in the east. This is where the two Herrenknecht Mixshields (S-731 and S-732) will be used. They install segments to secure the tunnel which are produced using moulds from Herrenknecht Formwork GmbH. For precision targeted control all eight Crossrail machines were equipped with navigation systems from Herrenknecht subsidiary VMT.
Group partners
The cutting wheel is lifted by crane 45 m into the depths and then adjusted with millimeter precision by hand.
Record achievements through optimal cooperation
The TBMs work around the clock, seven days a week. Herrenknecht guarantees they are operational 90 percent of the time. In fact, levels of 95 percent and more are achieved.
This is possible because Herrenknecht specialists are at the side of the construction companies‘ employees with their experience. They check components and replace worn parts with new ones, which are kept in stores at the worksites. They train the operators, accompany them on the machines around the clock, give advice during the drive. Such as, how changing small parameters in the control system can make the drive even more efficient and safer. And so records like these are made possible: in mid April S-722, named “Ellie”, managed a distance of 72 meters in 24 hours.
The breakthrough of the last of the eight Herrenknecht machines on May 23, 2015 was celebrated on a large scale two weeks later on June 4, 2015. In Victoria’s target shaft (EPB Shield S-720) UK Prime Minister David Cameron said: "Crossrail is an incredible feat of engineering that will help to improve the lives of working people in London and beyond. The project is a vital part of our long term plan to build a more resilient economy by helping businesses to grow, compete and create jobs right along the supply chain."
You can find the detailed reportage about the jobsite in our All Around Online Magazine #2
| Column 0 | Column 1 |
|---|---|
| Tunnelling length |
42,240 m |
| Geology | Soft ground, Heterogeneous ground, Chalk (up to 4MPa) with flint bands (up to 800MPa), London Clay (silty to sandy clay with fine sand and silt and beds of calcareous mudstone) |
| Contractors |
Lot C300: BFK JV; BAM Nuttall Ltd., Ferrovial Agroman (UK) Ltd., Kier Construction Ltd. Lot C305: Dragados Sisk JV; Dragados S.A., John Sisk & Son (Holdings) Ltd. Lot C310: Hochtief Murphy JV; Hochtief Solutions AG, J Murphy & Sons Ltd. |
| Machine data | 6x EPB Shield: Diameter: 7,080 mm Lining method: Segmental lining Cutterhead power: 1,920 kW Torque: 9,800 kNm 2x Mixshield: Diameter: 7,080 mm Lining method: Segmental lining Cutterhead powe: 1,120 kW Torque: 3,709 kNm |
We are ready!