The Channel Tunnel
The Channel Tunnel, (French: le tunnel sous la Manche; often nicknamed
the Chunnel in English) is a rail tunnel beneath the English Channel at the
Straits of Dover, connecting Cheriton in Kent, England and Sangatte in northern
France. A long-standing and hugely expensive project that saw several false
starts, it was finally completed in 1994. It is the second longest rail tunnel
in the world, surpassed only by the Seikan Tunnel in Japan. It is operated by
Eurotunnel plc.
In 1957 the Channel Tunnel Study Group was formed. It reported in 1960 and
recommended a railway tunnel of two main tunnels and a smaller service tunnel.
The project was launched in 1973 but folded due to financial problems in 1975
after the construction of a 250 m test tunnel.
In 1984 the idea was relaunched with an Anglo-French government request for
proposals to build a privately funded link. Of the four submissions received
the one most closely resembling the 1973 plan was chosen and announced on
January 20, 1986. The Fixed Link Treaty was signed by the two governments in
Canterbury, Kent on February 12, 1986 and ratified in 1987.
The planned route of the tunnel took it from Calais to Folkestone (a route
rather longer than the shortest possible crossing) and the tunnel was to follow
a single chalk stratum (which meant the tunnel was deeper than the previous
attempt). For much of its route, the tunnel is nearly 40 m under the seafloor,
with the southern section being deeper than the northern.
Digging the tunnel took 15,000 workers over seven years, with tunnelling
operations conducted simultaneously from both ends. The prime contractor for
the construction was the Anglo-French TransManche Link, a consortium of 10 construction
companies and 5 banks of the two countries. Engineers used large tunnel boring
machines (TBMs), mobile excavation factories that combined drilling, material
removal, and the process of shoring up the soft and permeable tunnel walls with
a concrete liner. After the British and French TBMs had met near the middle,
the French TBM was dismantled while the British one was diverted into the rock
and abandoned. Almost 4 million cubic metres of chalk were excavated on the
English side, much of which was dumped below Shakespeare Cliff near Folkestone
to reclaim 90 acres (360,000 m²) of land from the sea.
The Channel Tunnel consists of three parallel tunnels: two primary rail
tunnels, which carry trains north and south, and a smaller access tunnel. This access
tunnel, which is served by narrow wheeled vehicles, is interconnected, by means
of transverse passages, to the main tunnels at regular intervals. It allows
maintenance workers access to the tunnel complex and provides a safe route for
escape during emergencies.
When the two tunnels met 40 m beneath the English Channel seabed on December 1,
1990, in what was to become one of the "crossover halls" that allow
diversion of trains from one main tunnel to the other, it became possible to
walk on dry land from Britain to mainland Europe for the first time since the
end of the last ice age, over 13,000 years ago. The British and French efforts,
which had been guided by laser surveying methods, met with less than 2 cm of
error.
The tunnel was officially opened by Queen Elizabeth II and French President
François Mitterrand in a ceremony held in Calais on May 6, 1994.
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article "Channel Tunnel". You can explore more on the Wikipedia website. The text and the images
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Questions about the text
1. The Channel Tunnel was completed in 1994.
True.
False.
We don't know.
2. It took ten years to finish the tunnel.
True.
False.
We don't know.
3. The tunnel runs 40m under the sea.
True.
False.
We don't know.
4. There are three parallel tunnels inside the
Chunnel.
True.
False.
We don't know.
5. The tunnels from both ends met in 1990.
True.
False.
We don't know.



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