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Work in pairs. Explain the following statements.
1) One of the most important developments is the welding of rails.
2) The method of separate fastening has a number of advantages.
3) Rails are bolted to each other by means of fishplates.
4) Wooden and concrete sleepers have both advantages and disadvantages.
5) Keeping the ballast clean is essential.
Translate the following paragraph into Russian. Use a dictionary. Then compare your translation with a partner to improve.
Location and construction
Ideally, a railroad should be built in a straight line, over level ground, between large centres of trade and travel. In practice, this ideal is rarely approached. The location engineer, faced with the terrain to be traversed, must balance the cost of construction against annual maintenance and operating costs, as well as against the probable traffic volume and profit.
Graders, bulldozers, and similar equipment make it possible to dig deeper cuts through hillsides and to make higher fills where necessary to smooth out the profile of the track. Modern equipment has also helped to improve railroad roadbeds in other ways. Where the roadbed is unstable, for example, injecting concrete grout into the subgrade under pressure is a widely used technique. In planning roadbed improvements, as well as in new construction, railroads have drawn on modern soil-engineering techniques.
The track is laid on ballast, usually of crushed rock. The sleepers, or crossties, to which the rails are fastened, are embedded in the ballast. This is tightly compacted or tamped around the sleepers to keep the track precisely leveled and aligned. Efficient drainage of the ballast is critically important to prevent its destabilization. The depth of ballast depends on the characteristics of a line's traffic; it must be considerably greater on a track carrying frequent high-speed passenger trains, for example, than on one used by medium-speed commuter trains.
Read the Russian text, title and render it in English.
К нижнему строению пути относятся земляное полотно и искусственные сооружения. Земляное полотно – это фундамент ж.-д. пути.
Искусственные сооружения – это общее название таких необходимых элементов ж.д., как ж.-д. мосты, туннели, виадуки, дренажные (водопропускные) трубы, подпорные стенки и др.
Верхнее строение пути включает рельсы, рельсовые скрепления, шпалы, противоугоны, балласт, а также стрелочные переводы.
Железнодорожный путь – рельсы, уложенные на шпалы, соединены между собой и прикреплены к шпалам рельсовыми скреплениями. Это сооружение расположено на балластном слое (гравий, щебень и т.п.), который отсыпают на слой песка, покрывающий земляное полотно.
С увеличением скоростей, грузонапряженности, нагрузок на ось подвижного состава уменьшают количество стыков, устраивая бесстыковой путь из сварных рельсовых плетей (в России длиной до 800 м.)
Language spot
Passive Voice
Put the verb into the correct form
1) The track is supported on ballast. (support)
2) The track ___ by machines. (lay)
3) Rails ___ of steel. (make)
4) Periodically, ballast must ___. (clean)
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The Permanent Way | | | Assess your progress in this unit. Say which statements are true. |