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Breakthrough! The Crossrail story, Bristol

12 January, 2016 | 18:00 - 20:00

Breaking through during the tunnelling phase of the Crossrail project.
Breaking through during the tunnelling phase of the Crossrail project.

About this event

A network of new rail tunnels have been built by eight giant tunnel boring machines, to carry Crossrail's trains eastbound and westbound. Each tunnel is 21 kilometres/13 miles long, 6.2 metres in diameter and up to 40 metres below ground.

Crossrail's tunnelling marathon under London is now complete. Tunnelling began in May 2012 and ended at Farringdon in May this year with the arrival of tunnelling machine Victoria. Over the last three years, eight 1,000 tonne tunnel boring machines (TBMs) have bored 42km or 26 miles of new 6.2 diameter rail tunnels under London.

The machines were operated by "tunnel gangs" of 20 people, working in shifts around the clock to construct the tunnels, carving out around 3.4 million tonnes of earth. The tunnels, constructed using TBMs and in stations and caverns using sprayed concrete lining methods, weave their way between existing underground lines, sewers, utility tunnels and building foundations from station to station at depths of up to 42m.

Event materials

The following materials are available for download: