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your eyes tested? 10. The speed limit is to be introduced gradually. 11. The runways are
being lengthened at all the main airports. 12. This notice has been altered. 13. The dam-
aged ship was being towed into harbor when the towline broke. 14. This scientific theory
has been proved to be false. 15. Why wasn’t the car either locked or put into the garage?
16. For a long time the Earth was believed to be flat. 17. The referee was being escorted
from the football field by a strong police guard. 18. They should have planned the expedi-
tion more carefully. 19. He watched TV when the phone rang. Very unwillingly he turned
down the sound and went to answer it. 20. When I arrived, she had lunch. She apologized
for starting without me but said that she always lunched at 12.30.
Read the text and translate it with a dictionary if necessary.
R
AILWAY TRACK
The main component parts of the modem railway track do not differ greatly from
those of a hundred or more years ago. As then, railway track consists of two parallel rails
which are supported on crossties (ties, sleepers). The sleepers hold the rails in place and at
the right distance apart and play their part in spreading the load to the subgrade. The num-
ber and spacing of the sleepers depend largely on the weight of trains passing over the
track. The sleepers are laid on ballast, and the whole structure is supported on the sub-
grade. The rails are joined to each other by fastenings. High-speed railways use now con-
tinuous welded rails instead of standard ones because jointless tracks give better riding
qualities, last longer, reduce the cost of maintenance and increase the stability of the line.
The practice now is to weld standard 60 ft rail lengths into lengths of up to a mile or more.
There are several types of rails now used on our railways, such as R60, R75. R75 type
means that the weight of one meter of rail is 75 kg.
Recently the crossties consisted almost universally of wood treated with the special
material called creosote which prevents it from decay. Now concrete sleepers are widely
used on all the railways of the world. Metal plates, known as tie plates, protect the ties
from damage due to the cutting action of the rail.
Track ballast consists almost universally of crushed stone (broken stone), but some
other materials (slag, gravel, sand, etc.) are used as well. There is usually a lower layer of
large pieces of material (three to nine inches across) and an upper layer of half inch to two
inches. On this the sleepers are laid, and loose ballast of the smaller size is fitted in be-
tween them.
Although ballast is one of the main component parts of railway track, some coun-
tries prefer laying tracks without ballast. Thus, the slab track has been adopted for all
Shinkansen lines (high-speed lines in Japan). High-speed tests on the slab track showed
that the stability of the trains is much higher.
The distance between rails is called gauge. The gauge is not the same on different
railways of the world. The gauge on most railways in Europe, including Great Britain, is
1435 mm. As for the Russian railways, their gauge is 1520 mm. Finland is the only coun-
try in the European Community that has the same gauge as Russia. High-speed passenger
and freight trains can cross the border without stopping.
To provide safe and reliable railway traffic it is important to maintain railway track
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