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12 Suggest a heading for the text given above.

13 Use the following topics for discussion:

1 The functions of ballast.

2 Materials used for ballast.

3 The depth of ballast.

Text 5в Asbestos Ballast

Read the text in 6 minutes, trying to grasp its main idea.

Railways in addition to crushed stone ballast widely use the so – called "asbestos ballast". This ballast is the residue (остаток, отход) of asbestos concentration plants where the asbestos – bearing rock – serpentinite (серпентин) is crushed in producing high – grade asbestos. Asbestos ballast has a composition of granules of a specific size (for example of grain – size). It con­siderably differs from sand and gravel ballast.

The appearance of asbestos ballast should be regarded as a new phenomenon, running counter to the usual idea that the ballast acts as a draining factor. Asbestos ballast gives protection against dam­pness (влажность, сырость) of the track formation, and prevents pollution (загрязнение) of the ballast by coal, minerals and other similar substances. This type of ballast increases the elasti­city of the track and reduces the accumulation of residual diformations of the tracks, which is less intensive and is far more evenly (равномерно) distributed as compared to broken stone ballast. Asbestos ballast protects the track formation from the destructive effect of vibrations most successfully.

It is quickly consolidating under running trains and does not require extensive throughput tonnage to stabilize.

Neither have speed restrictions for trains after reballasting to be imposed. Labour consumptions in track levelling operations with asbestos ballast is 25 to 30 per cent less, yet the accuracy is higher than with broken stone ballast.

Asbestos ballast is placed directly onto the main formation surface, no subballast layer is provided. In this case the thiokness of the asbestos ballast layer is appointed as follows: 45(50) cm for a freight traffic density a year, 50(55) cm for 25 to 50, and 55 (60) cm for a freight traffic density of over 50: the figures in parentheses (скобки ) are for reinforoed – concrete sleepers.

1 Complete the following sentences according to the text.

1 Railways in addition to crushed stone ballast...

2 This ballast is...

3 The appearance of asbestos ballast should be regarded as...

4 Asbestos ballast gives protection...

5 This type of ballast increases...

6 Asbestos ballast protects the track formation from...

7 Asbestos ballast is quickly consolidating....

8 Labour consumptions in track levelling operations with as­bestos ballast is...

9 Asbestos ballast is placed...

10 The thickness of the asbestos ballast layer is appointed …

2 Find in the text information about the advantages of as­bestos ballast.

3 Give a short summary of text 5 b.

1 Learn the following words and word combinations from the text:

2 resistance – сопротивление, стойкость, устойчивость.

3 curve – кривая.

4 shoulder – наружная призма.

5 roller – поднятие почвы, вал.

6 permanent set – остаточная деформация.

7 stress – напряжение, усилие, нагрузка.

8 binding materials binders – связующие вещества.

9 film – пленка.

10 to weave – качаться, раскачиваться.

11 rubber mat – резиновый щит /ковер/.

Read text 5 С and find answers to the following questions:

1 How do some railway administrations try to increase resis­tance of the track skeleton across the gauge?

2 In what regions is it possible to increase a shoulder of ballasted prism or to establish'a roller?

3 Why is the thickness of the crushed stone bed 5 cm greater with einforced – concrete sleepers than with wooden ones?

4 What is the thickness of the crushed stone ballast оm rail­ways of the Soviet Union?

5 What is the crushed stone layer strengthened with binding materials for?

6 What is done in order to create hydro – isolation, thermoprotection and decrease the level of road – bed vibration In low part subballast?

In order to increase resistance of the track skeleton across the gauge, which is especially necessary in sharp curves, a num­ber of railway administrations, besides increasing of a shoulder of ballasted prism behind the ends of sleepers up to 40 – 50 cm and more (Great Britain, FRG and other), establish a roller with height of 15 cm. Such a desision is acceptable if the railway is not located in snow – drift regions, it allows to ley continuous wel­ded rail In sharper curves.

The experience of Railways shows that the accumulati­on of permanent set in track on reinforced – concrete sleepers is mo­re intensive then on wooden ones; for this reason, and also to le­vel out the stress on the main surface of the formation, in the Russia and other countries the thickness of the crushed stone bed is taken 5 cm greater with ralnforced – concrete sleepers that with wo­oden ones (on railways of the Russia, the thickness of the crushed stone under sleepers in the normal type of track is 25 and 30 cm, in the heavy type – 30 and 35 cm, and in the especially hea­vy – 35 and 40 cm).

МИНИСТЕРСТВО ОБРАЗОВАНИЯ РЕСПУБЛИКИ БЕЛАРУСЬ

УЧРЕЖДЕНИЕ ОБРАЗОВАНИЯ

“БЕЛОРУССКИЙ ГОСУДАРСТВЕННЫЙ УНИВЕРСИТЕТ ТРАНСПОРТА”

Кафедра иностранных языков

И. Н. КОМИССАРУК, В. И. КОМИССАРУК

АНГЛИЙСКИЙ ЯЗЫК

Учебно-методическое пособие для студентов

строительного факультета

Одобрено методической комиссией

строительного факультета

Гомель 2008

УДК 811.111(075.8)

ББК 81.2 Англ

А64

Авторы: И. Н. Комиссарук, В. И. Комиссарук,

Р е ц е н з е н т ы: зав. кафедрой иностранных языков канд.филол.наук, доцент И.Н.Пузенко (УО ГГТУ им. П.О.Сухого); ст. преподаватель кафедры иностранных языков М.И.Дроздова (УО БелГУТ ).

А64 Английский язык : учеб.-метод. пособие для студентов строительного факультета / И.Н.Комиссарук, В.И.Комиссарук; М-во образования Респ. Беларусь; Белорус. гос. ун-т трансп. – Гомель: БелГУТ, 2008.-98 с.

Учебно-методическое пособие состоит из шести уроков, каждый из которых содержит три текста по специальности, систему предтекстовых и послетекстовых упражнений для работы над лексикой и грамматикой.

Целью данного пособия является развитие навыков чтения и перевода текстов по специальности, овладение общеинженерной терминологией, а также усвоение грамматического материала.

Пособие предназначено для студентов строительного факультета.

УДК 811.111(075.8)

ББК 81.2 Англ

© Оформление. УО «БелГУТ», 2008