The UK government has unveiled a preferred route for second phase of the HS2 rail project

HS2 receives deconstructed giant tunnelling machines

Image credit: PA

Giant tunnelling machines for have been shipped over to the UK from Germany, to help construct railway routes for HS2.

They are expected to run for around three and a half years in order to create 16km long tunnels in the Chiltern area. The tunnels will reach as deep as 80m below ground, in order to reduce the impact of the lines on nearby countryside.

The two 170m long machines have been transported in more than 1,000 parts, and will be reconstructed in the UK.

The tunnels will have a diameter of 9.1m, giving enough space for the trains to pass through, and for emergency walkways on either side of the track.

As well as digging, they will simultaneously line the walls of the tunnel with concrete segments as they move forward

Last month it was revealed that HS2 would incorporate robotic arms into the machines known as Krokodyl which should help to improve both the efficiency and safety of the machines.

The material dug out by the machines, made by specialist firm Herrenknecht in Schwanau, south-west Germany, will be turned into slurry and used for landscaping at the site.

After years of opposition, the Tory government led by Boris Johnson finally gave the go ahead to begin constructing HS2 early this year, with works beginning in September.

HS2 Ltd chief executive Mark Thurston said the arrival of the TBMs is “a major step forward”.

He went on: “The launch of our first tunnelling machines will be a defining moment in the history of HS2 and our work to deliver a high-speed railway that will offer a low-carbon alternative for journeys across the UK.”

Speaking to the PA new agency, senior engineer James Reilly said: “We’ve designed our machines to make sure we have enough space in there. It’s not going to be too hot in there, but it will be warmer than the outside.”

With regards to adhering to Covid-19 safety procedures, he added that the workers should be able to maintain social distancing with one-way systems set up and mandatory face masks.

In January, an inquiry found that the total cost of HS2 could reach more than £100bn despite initial estimates of just £55bn. 

Sign up to the E&T News e-mail to get great stories like this delivered to your inbox every day.

Recent articles