Read the following text to find answers to the given the questions.

TEXT 5 PROGRESS IN TUNNEL ENGINEERING

Ex.4. Here are the answers. Write the questions.

Ex3. Complete the following sentences.

1) The English Channel is also called___. 2) Sailors know the English Channel as___. 3) People

have crossed the tunnel by___. 4) The idea of the tunnel construction___. 5) The British government

objected to___. 6) The first project of the tunnel___. 7) Ernst Beaumont was not allowed to___.

8) In 1950s a research group was set up___. 9) In 1963 the British government refused___. 10) The

Tunnel was opened for traffic___. 11) The Channel Tunnel actually consists of___. 12) If one of the

running tunnels is closed___ 13) A smaller third tunnel ___. 14) There is a roadway___. 15) The

service tunnel is linked to___. 16) In case of emergency or a train breakdown___. 17) The total

length of the Tunnel___. 18) The electric trains___. 19) A typical passenger shuttle___. 20) Freight

shuttles___. 21) Two electric locomotives are coupled___. 22) This railway is very convenient for

drivers because___. 23) The gauge of the tunnel railway___. 24) So far the project___. 25) The

Tunnel personnel___.

1) Nearly 200 years ago.

2) Albert Mathieu.

3) Because of financial difficulties.

4) On grounds of national security.

5) Only in 1988.

6) About six years.

7) On May 1994.

8) About fifty kilometers.

9) 4,000 vehicles per hour.

10) Two main single track tunnels with a service tunnel between.

a) When did people begin tunneling?

b) Where were the first tunnels built?

c) What were tunnels built for?

Tunneling is difficult, expensive and dangerous engineering work. Tunnels are built to provide

direct automobile or railway routes through mountain ranges or under rivers. Before the 19th century men had not acquired enough skill in engineering to carry out extensive tunneling. Tunnels, however, were known in ancient times. The first-known tunnel was dug in Babylon in about 2180–60 BC. It passed under the Euphrates River and connected the royal palace with a temple. An early Greek tunnel was completed in 687 BC on the island of Samos as part of an aqueduct system.

The Romans built many aqueduct tunnels throughout their vast empire. Their greatest feat was a

3.5-mile (5.6-kilometer) tunnel to drain Lake Fucino in Italy to create Fucino Basin. Few tunnels

were built during the next thousand years. Some irrigation tunnels were constructed in Spain during the early 1400s, and in about 1450 a project was begun in the Maritime Alp [Приморские Альпы] to link Nice and Genoa. This work, however, was never completed.

By the 17th century tunnels were being constructed for use as canals. During the 19th and 20th

centuries the development of railroad and, later, motor-vehicle transportation led to a tremendous

expansion worldwide in the number of tunnels and in their length.

Early tunnel-building techniques varied. The Egyptians used copper saws that were capable of

cutting soft rock, while the Babylonians constructed masonry tunnels. The Romans tunneled

through solid rock by heating the rock face with fire and then rapidly cooling it with water, causing the rock to crack. Tunnel building has always been hazardous, and often hundreds or even thousands of workers died constructing ancient tunnels. The development of modern tunneling technology has also included vast improvements in worker safety.

a) When was the first Alpine tunnel built? b) How is it called? c) What new device was

used during tunneling for the first time?

Ever since the early days of civilization in Europe the Alps have been a barrier to the movements of people. The first Alpine tunnel to be constructed was the Mont Cenus tunnel. This great project dates back to 1857. This tunnel is of great technical interest because at that time the only way to get through the rock was to use hand tools. At first the construction advanced very slowly. In fact, if it had continued at the initial pace, it would have taken 5 years to complete the tunnel! However, with compressed air drills and dynamite being introduced, progress was accelerated. Work on the Mont Cenus tunnel started in August 1857 and finished in December 1870.

a) What is the name of the second tunnel cut through the Alps? b) What is the length of

the tunnel? c) Why was it dangerous to build tunnels at that time?

The next great and extremely difficult task was the construction of the St. Gotthard tunnel.

Italian and Swiss engineers started working on this project in 1872. This tunnel 9.3 miles long was completed 9 years later as compared with 14 years required to make the Mont Cenus tunnel. It should be noted that during the period of construction no less then 800 men lost their lives because of poor ventilation. The only means of ventilating was the compressed air exhausted from the drills. It was so insufficient that the death rate among the workers was extremely great. Needless to say that the ventilation ought to have been much better.

a) What is the longest tunnel cut through the Alps? b) What was done to improve

ventilation in the course of tunneling? c) Why was a smaller bore (диаметр тоннеля)

adopted?

Both the Mont Cenus and the St. Gotthard tunnels are known to be single tunnels. But when it

was decided to bore the Simplon tunnel through the Alps, a different scheme was adopted because geological conditions in this part of the mountains were not simple. The planned length of 12.3 miles was greater than had been done before. According to the project two tunnels were cut, side by side, with transverse galleries connecting them at certain intervals. In this way ventilation was greatly improved and the removal of soil was made much easier. Each tunnel could take only one railway track, so a smaller bore was adopted. Had the tunnel been made the same size as the earlier ones, it might never have been completed. These arrangements made the construction much safer.

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