Tunnel boring Florence set to dig the Chiltern Hills

https://vimeo.com/548755037

Named after Florence Nightingale, the 170m long TBM will dig the first of a pair of 10-mile long tunnels under the Chiltern Hills. A second machine - ‘Cecilia’ - will launch in June 2021 to excavate the second tunnel at the South Portal site in Hertfordshire.

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“The work has truly begun on taking HS2 northwards,” transport secretary Grant Shapps said in a statement. “The tunnels these machines dig will ensure the benefits of our new high-capacity, high-speed railway run to the great cities of the North and Midlands, forging stronger connections in our country, boosting connectivity and skills opportunities and transforming our transport links.”

The first two TBMs will be operated by HS2’s main works contractor, Align, a joint venture formed of Bouygues Travaux Publics, Sir Robert McAlpine, and VolkerFitzpatrick.

Designed for the mix of chalk and flints under the Chilterns, the identical TBMs will dig separate tunnels for north and southbound trains. The cutter head will rotate at up to 3.2rpm with the machine expected to cover 15.6m per day.