2. Переведите на русский язык следующие английские словосочетания:

1. air-conditioning; 6. cleaning and circulating of air;

2. manufactu­ring processes; 7. ventilation system with fan and heater;

3. gas­eous impurities; 8. to dilute the carbon dioxide content;

4. accuracy of control; 9. a multistorey office block;

5. silencing arrangements; 10. air washer and dehumidifier

3. Найдите в тексте английские эквиваленты следующих словосочетаний:

1. кондиционирование воздуха; 6. воздухоочиститель и влагопоглотитель;

2. регулирование температуры; 7. приводить в движение;

3. производственный процесс; 8. машинное охлаждение;

4. газообразные примеси; 9. воздухонепроницаемая камера;

5. точность контроля; 10. распределение воздуха.

4. Найдите в тексте слова, имеющие общий корень с данными словами. Определите, к какой части речи они относятся, и переведите их на русский язык.

1. humidify 6. ventilate

2. distribute 7. gas­

3. arrange 8. circulate

4. enter 9. obtain

5. natural 10. investigate

5. Задайте к выделенному в тексте предложению все типы вопросов (общий, альтернативный, разделительный, специальный: а) к подлежащему, б) к второстепенному члену предложения).

6. Выполните анализ данных предложений, обратив внимание на следующие грамматические явления: формы и функции инфинитива, инфинитивные конструкции (сложное дополнение, сложное подлежащее), существительное в роли определения, функции слов one (ones), that (those), условные предложения:

1. Complete air-conditioning is known to involve the si­multaneous control of many factors.

2. Experiments led engineers to give up this theory.

3. The term air-conditioning is often used loosely to describe any ventilation system with fan and heater.

4. The downward system is often to be preferred because the cooled air naturally tends to drop after entering.

5. The term air-conditioning has been so widely and loosely used that the student should be careful in trying to under­stand its true meaning.

7. Ответьте на вопросы по тексту:

1. What does the term air-conditioning mean?

2. For what purposes is air-conditioning used?

3. What does com­plete air-conditioning involve?

4. What factors are most im­portant?

5. Formerly carbon dioxide was looked upon as a harmful element, wasn't it?

6. What is the modern concept of air-conditioning?

7. Upon what does comfort depend?

8. Составьте аннотацию к тексту (2-3 предложения).

9. Составьте реферат текста (10-15 предложений).

10. Составьте план текста и перескажите текст.

Вариант 5

1. Прочитайте и переведите текст:

PRESTRESSED CONCRETE

It was not until the end of the nineteenth century and the beginning of the present century that reinforced concrete really came into its own¹ as a structural material with a great variety of uses. Great advances have been made in the knowledge of its behaviour in structures and much experience has been gained in its use so that today it is deservedly a material of importance.

The outstanding characteristic of concrete is that it can be manufactured readily and cast in a mould to any desired shape. It can be said to combine strength with plasticity. The addition of reinforcement or the application of the more recent technique of prestressing adds to its strength and does not decrease its plasticity.

Concrete has a much higher strength when it is under compression, than it has when it is subjected to tension. In fact its tensile strength is only one-tenth of its compressive strength. Its ability to sustain shearing forces is also fre­quently inadequate. The purpose of reinforcing is to provide a material with a high tensile strength which can be cast in the concrete in such a way that it is able to take the tensile and shear stresses which would otherwise have to be taken by the concrete, and at the same time allows full advantage to be taken of the concrete's high compressive strength.

Prestressed concrete has captured the imagination of many designers for several reasons. It enables lighter construc­tion than ordinary reinforced work. This means that not only is less material required in prestressed members, but that reduced weight of the members makes for lighter columns and foundations. Less steel is required than in ordinary rein­forced concrete. The lightness of prestressed concrete also makes it particularly useful for precast work. It is not sub­ject to cracking, so that there is little danger of corrosion of prestressing wires, and the concrete will not weather easily.

Prestressed concrete depends for its reliability on first-class control of the concrete aggregates and mix proportions, the placing of the concrete, the quality of the prestressing wires or bars and the application of the precise degree of prestress to the wires. These requirements make it particularly suitable for factory production.

The idea of prestressing is an extremely simple one. If one has a material that has no tensile strength it will fracture immediately it is called on to take tension. If, however, the material is given an initial compression, then, when the tension force is applied the material will be able to withstand the tension provided it does not exceed the initial compres­sion.

The great merit of prestressed concrete is that, in giving to the concrete itself an effective tensile strength, it enables all the concrete to contribute to the strength of the member, unlike reinforced work where only the concrete in compres­sion is contributing.

Concrete. The concrete used in prestressed work is usually called high-strenth concrete to distinguish it from the ordinary strength concrete used in normal reinforced work. A cube crushing strength¹ of 4,500 Ib per sq in at 28 days would be reasonable minimum requirements. A prestressed member will not normally be removed from its casting bed until af­ter the prestress has been applied. This means that for econom­ical operation the concrete must gain sufficient strength to allow the prestressing to be done as early as possible, so a high early strength is very often an important requirement. Rapid hardening cements are often used for this purpose.

High early strengths can also be induced by a curing (выдержка бетона) process known as steam curing. This is es­sentially a factory operation and involves curing the cast concrete in a chamber containing steam at certain tempera­tures. The rate of gain of strength can be increased consider­ably by steam curing, the rate depending largely on the tem­perature.

Getting the Best from Prestressed Concrete. Although prestressed concrete is increasingly used for buildings, its full potentialities have not yet been realized.

There must be full co-operation between architect, engi­neer and contractor if full advantage is to be taken of pre­stressed concrete. The most interesting and successful build­ings in recent years have been those in which all three have collaborated¹ closely from the start.

The practical, economical and aesthetic benefits of pre­stressed concrete for buildings are evident. From the practi­cal viewpoint, it permits large spans with relatively shallow-section members even when heavy loads are required. This means fewer columns, more unrestricted floor space and, of course, a reduction in weight and floor-to-floor heights.

Economically, prestressing means a saving in materials. It is particularly economical where large spans or heavy loads, or both, are involved by prestressed concrete. The advantages of large uninterrupted spans from the aesthetic point of view are self evident, as are the canopies and canti­levers that prestressing makes possible.

For the framed multistorey block, prestressing is most useful where the open flexible plan is required. Large spans and the minimum of internal columns are necessary, and prestressed beams and floors can provide an efficient and attractive solution.

An interesting development in prestressed concrete re­cently has been its popularity for multistorey car parks, where unobstructed space for parking manoeuvring is essential. One of the most successful multistorey car parks houses some 800 cars on six floors, many more similar car parks being planned.