Text 2. THE HISTORY OF TUNNELING

Part 1

It is probable that the first tunneling was done by prehistoric people seeking to enlarge their caves. All major ancient civilizations developed tunneling methods. In Babylonia, tunnels were used extensively for irrigation; and a brick-lined pedestrian passage some 3, 000 feet (900 metres) long was built about 2180 to 2160 bc under the Euphrates River to connect the royal palace with the temple. Construction was accomplished by diverting the river during the dry season. The Egyptians developed techniques for cutting soft rocks with copper saws and hollow reed drills, both surrounded by an abrasive, a technique probably used first for quarrying stone blocks and later in excavating temple rooms inside rock cliffs. Even more elaborate temples were later excavated within solid rock in Ethiopia and India.

The Greeks and Romans both made extensive use of tunnels: to reclaim marshes by drainage and for water aqueducts, such as the 6th-century-BC Greek water tunnel on the isle of Samos driven some 3, 400 feet through lime-largest stone with a cross section about 6 feet square. By that time surveying methods (commonly by string line and plumb bobs) had been introduced, and tunnels were advanced from a succession of closely spaced shafts to provide ventilation. Ventilation methods were primitive, often limited to waving a canvas at the mouth of the shaft, and most tunnels claimed the lives of hundreds or even thousands of the slaves used as workers.

Because the limited tunneling in the Middle Ages was principally for mining and military engineering, the next major advance was to meet Europe's growing transportation needs in the 17th century. The first of many major canal tunnels was the Canal du Midi (also known as Languedoc) tunnel in France, built in 1666-81 by Pierre Riquet as part of the first canal linking the Atlantic and the Mediterranean.

A notable canal tunnel in England was the Bridgewater Canal Tunnel, built in 1761 by James Brindley to carry coal to Manchester from the Worsley mine. Many more canal tunnels were dug in Europe and North America in the 18th and early 19th centuries. Though the canals fell into disuse with the introduction of railroads about 1830, the new form of transport produced a huge increase in tunneling, which continued for nearly 100 years as railroads expanded over the world.

Much pioneer railroad tunneling developed in England. A 3.5-mile tunnel (the Woodhead) of the Manchester-Sheffield Railroad (1839-45) was driven from five shafts up to 600 feet deep.

COMPREHENSION CHECK

I. Decide whether the following statements are true or false according to the text:

1. The first tunnels were built by Romans.

2. In the Middle Ages tunnels were built to connect castles with churches

3. The Egyptians used advanced technologies for cutting soft rocks.

4. The Greeks and Romans widely used tunnels.

5. Ventilation methods were limited to waving a canvas at the mouth of the shaft.

6. Transportation needs greatly increased in the 17-th century in Europe.

7. The first canal tunnel was built in France to connect The Indian and the Mediterranean.

8. James Brindley built the Bridgewater Canal Tunnel to carry coal.

9. The introduction of railroads slowed the building of canal tunnels.

10. Railroad tunneling was developed mainly in England.

II. Answer the questions

1. Why did prehistoric people do the first tunneling?

2. Who developed tunneling methods?

3. How were tunnels used in ancient times?

4. What method had been introduced by the 6-th century B.C.?

5. What were ventilation methods like?

6. What were tunnels built for in Middle Ages?

7. Why were canal tunnels built in the 17-th century?

8. What canal tunnels do you know?

9. Why did the canal tunnels fall into disuse about 1830?

10. When was railroad tunneling developed?

LANGUAGE FOCUS

III. Match the words with their synonyms.

1. to look for a) extensively

2. to expand b) to connect

3. widely c) to divert

4. to link d) advance

5. to complete e) to seek

6. to draw aside f) primitive

7. approach g) to accomplish

8. simple h) to enlarge

IV. Match the words with their opposites

1. modern a) irrigation

2. drainage b) expand

3. fill up c) prehistoric

4. plain d) notable

5. source e) mouth

6. civil f) elaborate

7. obscure g) military

8. narrow h) excavate

V. Fill in the prepositions.

1) To be used … sth, 2) to connect sth … sth, 3) to make use … sth, 4) to limit … sth, 5) … the mouth, 6) to carry sth … sth, 7) with the introduction … sth, 8) to expand … the world, 9) increase … sth, 10) to fall … disuse.

VI. Insert the words from the list

preservation, dangerous, heating, sandstone, road, lining, cooling, safety, to drain, salt mine

1. Tunneling is difficult, expensive and … engineering work.

2. Temple on the Nile was built in … about 1250 B.C. for Ramses II. In the 1960’s it was cut apart and moved to higher ground for … before flooding from the Aswan High Dam.

3. Perhaps the largest tunnel in ancient times was a 4800 foot-long, 25 foot-wide, 30 foot-high … tunnel between Naples and Pozzuoli, executed in 36 B.C.

4. To save the need for a …, most ancient tunnels were located in reasonably strong rock. It was broken off by so called fire quenching, a method involving … the rock with fire and suddenly … in by dousing with water.

5. In A.D. 41 the Romans used some 30 000 men for 10 years to push a 3.5 mile (6 kilometers) tunnel … Lacus Fucinus.

6. Far more attention was paid to ventilation and … measures when workers were freemen, as shown by archaeological diggings at Hallstall, Austria, where … tunnels have been worked since 2500 B.C.

VII. Make the precis of the text

Text 2. THE HISTORY OF TUNNELING

Part 2

The great civil engineers of the nineteenth century were drawn into really grand tunneling. Two new kinds of transport created a need for tunnels. Railways had to lie on almost flat ground, and so did England's huge canal system. By the early 1800s those canals had become England's primary commercial trade network. Canals and railways, like the Roman aqueducts before them, spawned heroic tunneling through obstacles. Tunneling under rivers was considered impossible until the protective shield was developed in England by Marc Brunei, a French emigre engineer. The first use of the shield, by Brunei and his son Isambard, was in 1825 on the Wapping-Rotherhithe Tunnel through clay under the Thames River. The tunnel was of horseshoe section 22'/4 by 37'/2 feet and brick-lined. After several floodings from hitting sand pockets and a seven-year shutdown for refinancing and building a second shield, the Brunels succeeded in completing the world's first true subaqueous tunnel in 1841, essentially nine years' work for a 1, 200-foot-long tunnel. During the 19th and 20th centuries, the development of railroad and motor vehicle transportation led to bigger, better, and longer tunnels. With the latest tunnel construction technology, engineers can bore through mountains, under rivers, and beneath bustling cities. Before carving a tunnel, engineers investigate ground conditions by analyzing soil and rock samples and drilling test holes. Today, engineers know that there are three basic steps to building a stable tunnel. The first step is excavation: engineers dig through the earth with a reliable tool or technique. The second step is support: engineers must support any unstable ground around them while they dig. The final step is lining: engineers add the final touches, like the roadway and lights, when the tunnel is structurally sound. Worldwide efforts are under way to accelerate improvements in the technology of underground construction and are likely to be stimulated as a result of the 1970 OECD International Conference recommending improvement as government policy. The endeavour involves specialists such as geologists, soil- and rock-mechanics engineers, public-works designers, mining engineers, contractors, equipment and materials manufacturers, planners, and also lawyers, who aid in the search for more equitable contractual methods to share the risks of unknown geology and resulting extra costs.

COMPREHENSION CHECK

I. Decide whether the following statements are true or false according to the text:

1. The great military engineers of the 19-th century were drawn into grand tunneling.

2. The development of new kinds of transport created a need for tunnels.

3. By the early 1800s railways had become England’s primary commercial trade network.

4. The development of the protective shield made possible the construction of tunnels under rivers.

5. The first use of the shield was done by Isambard in 1825 under the Thames River.

6. The world’s first true subaqueous tunnel was completed in 1841.

7. The development of railroad and motor vehicle transportation accelerated the construction of tunnels.

8. Engineers must investigate ground conditions after the completion of the tunnel.

9. There are four basic steps in building a stable tunnel.

10. The endeav our involves a wide range of specialists.

II. Answer the questions.

1. Why were the engineers of the 19-th century drawn into grand tunneling?

2. What had become England’s primary commercial trade network by the early 1800s?

3. Who developed the protective shield?

4. When and where was the first use of the shield?

5. How much time did it take to build the world’s first true subaqueous tunnel?

6. What can engineers do using the latest tunnel construction technology?

7. How are ground conditions investigated?

8. What are the steps of tunneling?

9. When is excavation done?

10. Who is involved in tunneling?

LANGUAGE FOCUS

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