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Unit 4. Railway track construction
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Vocabulary
1) a track - железнодорожный путь, железнодорожное полотно
2) a permanent way - верхнее строение пути
3) a sleeper (a tie (Am)) - шпала
4) a subgrade - земляное полотно
5) pre-stressed concrete - преднапряженный железобетон
6) to weld - сваривать, приваривать
7) a baseplate - плита
8) a pad - подкладка, прослойка, подушка
9) resilient fastenings - упругие крепления
10) a cut spike - рельсовый костыль
11) scarce - недостаточный
12) maintenance - техническое обслуживание, путевые работы
13) axle load - осевая нагрузка
14) fishplates - стыковые накладки
15) friction - трение
The track on a railway (BE) or railroad (AE), also known as the permanent way, is the structure consisting of the rails, fasteners, railroad ties or sleepers (British English) and ballast (or slab track), plus the underlying subgrade.
Section through railway track and formation
The dominant track form worldwide includes flat-bottom steel rails supported on timber or pre-stressed concrete sleepers, which are rested on crushed stone ballast. Most railroads with heavy traffic use continuously welded rails supported by sleepers (ties) attached via baseplates which spread the load. A plastic or rubber pad is usually placed between the rail and the tieplate where concrete sleepers (ties) are used. The rail is usually held down to the sleeper (tie) with resilient fastenings, although cut spikes are widely used in North American practice. For much of the 20th century, rail track used softwood timber ties and jointed rails. Pre-stressed concrete sleepers (ties) are often used where timber is scarce and where tonnage or speeds are high. Steel is used in some applications. The track ballast comprises crushed stone, in order to support the ties and allow some adjustment of their position, while allowing free drainage.
A disadvantage of traditional track structures is the heavy demand for maintenance, particularly surfacing (tamping) and lining to restore the desired track geometry and smoothness of vehicle running. This can be overcome by using ballastless track. In its simplest form this consists of a continuous slab of concrete (like a highway structure) with the rails supported directly on its upper surface (using a resilient pad).
Rail is graded by weight over a standard length. Heavier rail can support greater axle loads and higher train speeds without sustaining damage than lighter rail, but at a greater cost. The traditional method of joining the rails is to bolt them together using metal fishplates, producing jointed track. For more modern usage, particularly where higher speeds are required, the lengths of rail may be welded together to form continuous welded rail (CWR). Because there are few joints, this form of track is very strong, gives a smooth ride, and needs less maintenance; trains can travel on it at higher speeds and with less friction. Welded rails are more expensive to lay than jointed tracks, but have much lower maintenance costs. The first welded track was used in Germany in 1924 and the US in 1930 and has become common on main lines since the 1950s.
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Read the text again and answer the questions:
1) What does the permanent way consist of?
2) What components does the dominant track have?
3) Where are pre-stressed sleepers used?
4) Traditional track structures have some drawbacks, don`t they?
5) When were the first welded tracks applied?
Exercises:
1) Find the English equivalents in the text:
1) скрепления
2) рельс
3) древесина
4) бесстыковой путь, путь из сварных рельсовых путей
5) щебень
6) распределять нагрузку
7) стыковые рельс
8) свободный водоотвод
9) сплошная плита
10) затраты, стоимость
2) Word formation. Form the adjectives from the given words using these suffixes: -ic, -al, -ous, -less, -ive:
1) In the morning they had a __________ continental breakfast. (tradition)
2) The latest ______________ research shows that our galaxy is expanding. (science)
3) She was _________ to find out what the parcel contained. (curiosity)
4) The children go to one of these ____________ schools where new educational standards has been introduced. (progress)
5) It was a ___________ night when everyone can see millions of stars in the dark sky. (cloud)
6) The room is _______________ enough to place a big Christmas tree. (space)
7) This company is offering a very ______________ salary. (attract)
3) Relative clauses. Fill in the gaps in the sentences with which, who, where, when, whose:
1) Cut spikes are large nails with an offset head ________ are used to secure rails and base plates to railroad ties in the track.
2) George Stephenson was an English engineer _________ built a successful steam locomotive “Rocket”.
3) In the 19th century most people were afraid of railways _________ they first appeared.
4) Richard Trevithick, _______ working model of a steam locomotive was demonstrated in 1808, first attempted to use the steam engine to draw passengers and freight trains.
5) The first steam locomotive in Russia was built by the Cherepanovs ________ were talented and skilled workman of their time.
6) The place _________ the ends of the rails meet in the track is known as the rail joint.
7) The railroads have a switch ________ makes the trains pass from one track to another.
8) Russia is the country ________ the uniform gauge of 1,520 mm is adopted.
Discussion Corner.
1) The evolution of railways
2) Track gauge
3) Switches and crossings
4) Famous civil engineers of the world
5) Railroad ecology
REFERENCES:
1.www.railwaygazette.com
2.www.wikipedia.com
3. The newspaper "Gudok" 16 July 2012
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