HS2 Launches Second TBM to Tunnel Under London

A second 140 metre long, 2,050 tonnes tunnel boring machine (TBM) has begun its journey across London for HS2.

This was switched on by HS2 Civils Delivery Director Mike Lyons.

HS2 launches first London tunnelling machine - Sushila
HS2 launches second London tunnel boring machine – Caroline

Named Caroline, after the first female professional astronomer Caroline Herschel, this TBM is the fifth of ten being launched by HS2 to construct the project’s railway tunnels.

Caroline’s launch closely follows that of TBM Sushila, which was switched on three weeks ago at the same West Ruislip site.

Since its launch, Sushila has already travelled 70 metres.

Caroline will be operated by a 15-strong crew from HS2’s main works civils contractor Skanska Costain STRABAG JV (SCS JV), which will work in shifts.

A further 25 workers will directly support each tunnel drive on the surface.

Travelling an average of 14 metres a day, Caroline will now dig non-stop for the next 22 months (apart from Christmas Day) to bore five miles of the twin-bore Northolt Tunnel.

A total of 4,207 8.5 tonnes tunnel segment rings will be placed to create the tunnel.

Each ring will be made of seven concrete segments, manufactured in the UK by Pacadar.

Mike Lyons, HS2 Civils Delivery Director, said:

“HS2's construction continues to gather pace, and the launch of the fifth tunnel boring machine on HS2 is another significant moment for Britain’s number one levelling-up project.”

Once Caroline and Sushila reach their destination at Greenpark Way, they will be dismantled and extracted from a 40-metre-deep shaft.

Next year two other TBMs will set off towards Greenpark Way from HS2’s Victoria Road site to build a further 3.4-mile twin-bore tunnel.

Combined, the quartet of TBMs will build 8.4 miles of twin bored tunnels between West Ruislip and the new HS2 super hub station at Old Oak Common.

Another 4.5-mile twin-bore tunnel travelling from Old Oak Common to Euston will complete HS2’s journey to its London terminus.

Get your news featured on Railway-News

Please fill in the contact form opposite. A member of the team will be in touch shortly.

    We'd love to send you the latest news and information from the world of Railway-News. Please tick the box if you agree to receive them.

    For your peace of mind here is a link to our Privacy Policy.

    By submitting this form, you consent to allow Railway-News to store and process this information.

    Follow Railway-News on LinkedIn
    Follow Railway-News on Twitter