A dedicated team of engineers is working around the clock to install the railway systems that will transform the new tunnels and stations into the UK’s newest railway. This includes the installation of track, tunnel ventilation, power, signalling, communications and overhead line equipment.
More than 50km of new, permanent track has been installed between Westbourne Park in west London and through to Plumstead and Pudding Mill Lane in the east. The final section of track was completed in the eastbound tunnel of the new Whitechapel station in July 2017.
Tunnel fit-out in numbers
Powering the railway
The fleet of new Elizabeth line trains will be powered by overhead lines on the surface sections of the route and by an overhead catenary system in the new tunnels.
Meet the fleet
A fleet of customised machinery specially built for the Crossrail project has been used in the fit-out of the tunnels.
Four giant multi-purpose gantries – which have been specifically designed for Crossrail - will carry and locate the track in the tunnels, before it is concreted into place.
Installing the tracks
Five different types of track have been laid in the Elizabeth line tunnels:
- Standard track slab: this forms 80% of track on Crossrail’s central section
- Direct fixed track: used in the Victorian engineered Connaught Tunnel
- High attenuation sleepers: similar to standard slab, used only in a few small areas to reduce noise/vibration
- Floating track slab light: used to reduce noise and vibration underneath Soho
- Floating track slab heavy: used to reduce noise and vibration underneath the Barbican
The majority of the track in the central section is formed from standard track slab. This connects with the other track forms that will be used at specific locations. A total of 41.2 km of standard track slab has been installed on Crossrail using fibre reinforced concrete.
Over 63,000 sleepers and 51,419m of rail have been installed along with more than 800 sections of Long Welded Rail (LWR)
13,500 m3 of concrete – enough to fill several Olympic sized swimming pools – was poured by the concreting train as part of the track installation.
DIRECT FIXED TRACK
Direct fixed track has been used within Connaught Tunnel. The track bed is a concrete reinforced structure.
It allows engineers to create a flat surface on top of the significant undulations in the ground and to work within the height restrictions which are a feature of this Victorian engineered tunnel. A total of 2.6 km of direct fixed track was installed on Crossrail.
FLOATING TRACK SLAB (LIGHT)
Floating track slab (light) has been installed between Tottenham Court Road and Bond Street to minimise noise and vibration impacts from the operating railway on nearby recording studios and hotels which is a requirement of the Crossrail Act.
The track slab floats on a combination of elastomet rubber bearings and heavy duty springs. The track slab is constructed and then jacked up to accommodate the bearings and springs. A total of 1.97 km of floating track slab (light) was installed on Crossrail.
FLOATING TRACK SLAB (HEAVY)
Floating track slab (heavy) was installed in the Farringdon area due to the close proximity of the Barbican. It sits on heavy duty springs. A total of 1.34 km of floating track slab (heavy) was installed on Crossrail.
Due to the extra depth added by the spring base of the floating track, a shallower sleeper is needed. To ensure that the shallower sleeper remains durable and effectively minimises noise and vibration, an incredibly dense concrete called Magnadense is used. Magnadense is over twice as dense as normal concrete due to its natural iron ore content.