7. Ответьте на вопросы по тексту:

1. What are concrete blocks made from?

2. What is a very common building material for the load-bearing walls of buildings?

3. Why are exposed surfaces generally given a decorative finish of stucco, brick, paint or siding?

4. What can be made virtually any color and, with integral water repellents?

5. What are cinder blocks made from?

6. When was AAC first developed by a Swedish engineer?

7. What can be coated with a stucco compound or plaster against the elements?

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

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

10. Составьте план текста и перескажите текст.

Вариант 9

1. Прочитайте и переведите текст:

Some problems of the design of structures

From the beginning of recorded time mankind has designed and erected structures of great size and beauty. The gigantic pyramids in Egypt still stand today and are a proof of the great engineering skill of the ancient inhabitants of the Nile valley. Similarly, the impressive marble-columned Parthenon on top of the Acropolis in Athens shows what great artists the ancient Greeks were. Built in the fourth century before our era, its classic beauty still delights numer­ous tourists every summer. There are many other examples of the engineering and architectural structures of ancient times that have more or less successfully withstood the ruinous effect of time throughout centuries.

However, it is only in relatively modern times that the design of structures or machines has become a science rather than an art. It is the application of the rational principles of the science of Strength of Materials which provides the fundamental basis for all machine and structural design.

The great technological developments of the twentieth century — in structures such as skyscrapers and in machines such as airplanes, automobiles — have placed great demands and responsibilities upon design and structural engineers. Yet every day demands arise for structures and machines of still greater strength at less weight and with greater econ­omy. The designer must also constantly remember of safety, and should failure occur before the expected life of the ma­chine or structure is at an end, it is he who will be held re­sponsible. Such failures are indeed rare, but when one does take place, it calls attention to the great responsibilities of the design engineers.

The design of residential areas. The term "design" in connection with residential areas means the arrangement of the various parts (the houses, roads, and so on) in such a way that they function properly, can be built economically and give pleasure to look at. The appearance of the area develops from its function and the way it is built, and is not something which is applied after the scientific, constructional and economic problems have been solved. These latter problems which are at the root of design, have received a fair share of attention in technical publications, and judging by results, are better understood than those concerned with appearance.

The term "residential area" is commonly taken to mean an area of urban development in which the majority of build­ings are dwellings and from which conflicting buildings are excluded. It has now become generally accepted that an area of dwellings, however well designed, is not by itself suffi­cient to meet the needs of the inhabitants. Schools, shops, playing fields, a meeting hall and other communal facilities are necessary to meet these needs, and an area which contains them is generally called "a neighbourhood". There may be very wide variations in size and shape between one neighbourhood and another, depending on the structure of the town as a whole and on the topography.

There is a strong aesthetic argument for subdividing the neighbourhood into housing units. An area of some two or three thousand dwellings is likely to be exceedingly dull in appearance, simply because there is little visual relief from bricks and mortar. Even a variety of dwellings will not help matters, because a general impression of the same kind will remain. If, on the other hand, the area is subdivided into a series of areas, each having its own characteristics (so that it is distinguished from the others), and if all of them are held together by the structure of the neighbourhood plan, there will be variety through the contrasts of each area and unity within the neighbourhoods as a whole.

New factory sets an example to its own customers. The new 130,000 sq ft factory making heating and ventila­tion equipment, provides more than 100, 000 sq ft of working area and has enabled to bring research and development ac­tivities under the same roof as all production facilities. The site also allows for further expansion to double the present size of the factory.

Of the overall design, a major share of attention was given to the roof. The umbrella roof, with main spans of 105x40 ft, is supported by only 11 free-standing columns, excluding those in the crane bays.

To provide full protection against overheating in summer, the roof is double-glazed and has anti-sun glass on the south side. A pneumatically-controlled ventilation scheme was installed to carry away the unwanted heat. Roof sheeting was selected for its low U-value and the interior was lined with acoustic board supporting an inch of loosely-packed glass fibre. Thus, heat insulation in summer, cold insulation in winter and general noise insulation were all accounted for simultaneously.

Although the choice of roofing materials have to some extent minimized the effects of summer overheating, a com­prehensive ventilation scheme has been installed. The pro­duction area has 50 ventilators, all pneumatically controlled; 30 intake units are each capable of supplying 4,000 cu ft/min of fresh air, partially or fully recirculated air.

Three powered roof extract ventilators, individually con­trolled, have been installed above the welding bay to main­tain a slight negative pressure so that welding fumes cannot penetrate the main production area.

Heating is by oil-fired heaters sited around the wall of the working area.

The entire factory is covered by automatic fire ventila­tion technique in which a fusible link is incorporated into each ventilator.

The factory is fronted by the office building and adjoins the research and development laboratory. There are two can­teens, the larger of the two being designed for use as a lecture and dance hall and cinema.

Research is regarded as one of the most important activi­ties at the new factory. Three wind tunnels are in daily use for the testing of all products and certain items of heating equipment. An acoustic cell 40x15x18 ft high has been built to rest the sound level of heaters and powered venti­lators and a modern frequency analyser is in use, along with gas sampling equipment and precision recorders.

Tests are carried out on the noise level and power con­sumption of electric motors, ventilation control systems and thermostatic controls. Basic flame characteristics and com­bustion chemistry, the flow of gases, and the characteristics of fans and motors are some of the aspects studied in heat research, while in ventilation, the laboratory is constantly examining the whole field of aerodynamics and its relation to the movement of air.