II. Learn the following words and word combinations to the text :

concrete [`kOnkri:t] – бетон, бетонировать

dense [dens] – плотный

heat-insulating – теплоизоляционный

heat-resistant – жаростойкий

fast-hardening – быстротвердеющий

high-strength – высокопрочный

lime concrete – силикатный

setting [`setiŋ] – схватывание

hardening [`ha:dniŋ] – твердение

cellular [`seljula] – ячеистый

acid-resistant [`Æsid] – кислотостойкий

fire-resistant [faiƏ] – огнестойкий

building site [`sait] – строительная площадка

monolithic = in-situ [in­'saitju:] – монолитный

precast [pri`kast] – сборный

to influence [`influens] – влиять на, воздействовать

water-cement ratio [`rei∫iou] – водоцементное отношение

quality [`kwOliti] – качество

supporting elements [sƏ`po:tiŋ] – опорные элементы

slab [slæb] – плита

hydraulic engineering structures [hai`dro:lik] – гидротехнические сооружения

channel [t∫ænl] – канал

road surfaces [`sƏ:fisiz] – дорожные покрытия

base – основание

marine concrete  [mƏ`r i:n] – гидротехнический бетон для морских сооружений

 

III. Give the synonyms to the following words and translate them into Russian.

 

Model:to use = to utilize - использовать

 

To construct, to vary, different, aim, material, ordinary, man-made, to classify, to apply, general, to make, rapid, to resist, to speak, special.

 

IV. Read and translate the text

 

CONCRETE

Concrete is one of the constructive building materials which led to great innovations: reinforced concrete and prestresssed concrete.

It was used by the Egyptians, Greeks and Romans in the construction of roads, tunnels, bridges, aqueducts, town walls and even underwater structures. Some of them have survived for example the Pantheon. This famous concrete building was conctructed by Roman hands. Today it stands in the business district of Rome – much as it was built some 18 centuries ago.

As cement was not known in those times, concrete was made of clay and later of gypsum and lime.

At present concrete is made by mixing water, cement and aggregates usually sand, gravel and crushed stone.

There are four stages in producing concrete: 1) preparing the raw materials 2) their mixing, 3) forming and 4) hardening. The resulting material is strong, durable, hard, heavyweight or lightweight, acid-, air-, water-, gas-, heat-, fire-, and corrosion-resistant.

There are different kinds of concrete: dense, lightweight, super-heavy, extra-lightweight, cellular, heat-resistant, high-strength. For special purposes acid and heat-resistant superheavy concrete is used.

The kind of concrete depends on the aggregates used.

There are different methods in producing concrete. It may be prepared right at the building site and is called monolithic or in-situ concrete. It may be prepared at a factory and is called precast.

The strength of any concrete is influenced by the following factors:

· the activity of cement;

· the water-cement ratio;

· the quality of aggregates;

· the hardening conditions.

Concrete today is widely used in construction:

1) for supporting elements of buildings: beams, floors, slabs, panels, columns;

2) for hydraulic engineering structures dams, facing of channels;

3) for road surfaces and bases.

Concrete is one of the main constructive building materials in the world.

 

V. Put in the correct prepositions.

1. Concrete is one … the constructive building materials.

2. Concrete is a mixture... water, cement and aggregates.

3. There are four stages... producing concrete.

4. Concrete may be prepared right... a building site.

5. It may also be prepared... a factory.

6. The kind of concrete depends... the aggregates used.

7. Concrete has many advantages... other building materials.

8. The strength of any concrete is influenced... many factors.

9. Concrete is widely used... construction... supporting elements.