1. Find the correct headings of the paragraphs.

1. The main characteristics of concrete.

2. The chief principles of plastics classification.

3. Factors that influence mass production of prefabricated large-size concrete and reinforced-concrete structural elements.

4. New tendencies in the choice of building materials.

5. The advantages of reinforced concrete.

2. Read the text again and answer the following questions.

1. For what types of construction are reinforced concrete structures and elements used?

2. What new materials have come into use both in industry and building?

3. In what industrial fields are plastics used?

3. Read the following sentences and divide them into three groups ‘Concrete’, ‘Brick’ and ‘Plastics’.

1. There are some kinds of structural materials that have appeared comparatively recently, sometimes they consist of one polymer. But in building industry some complex materials consisting of a polymer and other components are used.

2. In many cases bricks too are very satisfactory for use in the construction.

3. There are some kinds of materials which are brittle and cannot withstand tensile stress.

4. If steel is introduced into some kind of material it changes its property.

5. Some building materials offer a good resistance to compressive loads.

6. In respect of physical and mechanical properties these materials are divided into rigid, semi-rigid and soft.

4. Choose the one best answer a, b, c to the statements.

1. Using prefabricated or precast elements ...

a) depends only on the kind of load to which it is subjected.

b) builders perform a considerable amount of building work not in site but at a factory.

c) made possible mass production of large-size structural elements.

2. Reinforced concrete is a building material in which ...

a) such properties as small volume weight and high thermal conductivity are combined.

b) physical and mechanical properties at a normal temperature of 20°C make it semi-rigid and soft.

c) the joint functions of concrete and steel are advantageously utilized.

3. Bricks generally present a pleasing appearance and ...

a) they are light-weight building materials.

b) cannot be used in structures subjected to tensile stresses.

c) can be obtained with various qualities, colors and textures.

Text 3. Advanced Composite Materials

Match the following words and translations.

1. composite material 2. potentiality 3. plywood panel 4. light-weight honeycomb structures 5. consumption 6. emergence 7. to outperform 8. conventional material 9. sparingly 10. exception

A. звичайний матеріал B. фанерна плита C. легкі пористі структури D. потенційна можливість E. витрати F. поява G. виключення H. перевершувати I. композитний матеріал J. з розрахунком

Composite materials are among the oldest and newest of structural materials. Men discovered early that when two or more materials are used together as one, the combination often behaves better than each of the materials alone. Following this principle they combined clay and straw to make bricks. Then with some notable exceptions, the further potentialities of composite materials remained virtually untapped for centuries while monolithic materials, such as iron and copper, served the major needs of an advancing technology. Even in the more recent times with the coming of reinforced concrete, linoleum, plasterboard and plywood panels were somewhat out of mainstream of materials development and technology.

During the 1930’s and 1940’s, however, light-weight honeycomb structures, machine parts made from compressed metal powders and plastic reinforced with glass fibers became commercial realities. These developments marked the beginning of the modern era of composite engineering materials. The use of composite materials has been steadily growing. The consumption of the fiber reinforced plastics, for example, has been increasing at the phenomenal rate of 25 per cent annually. Nevertheless, the emergence of a strict discipline and technology of composite materials is barely 20 years old.

There are two major reasons for the current interest in composite materials. The first is simply the demand for materials that will outperform the traditional monolithic materials. The second, and the more important in the long run, is that composites offer engineers the opportunity to design totally new materials with the precise combination of properties needed for a specific task. Although the new composites are usually more costly than conventional materials, they can be used more sparingly, because of their superior qualities.