Improve your skills in English:

Play a situation with these idioms

1. I want to speak my mind today (say exactly what I think)

2. To be long winded (say things in a long, indirect way)

3. To talk rubbish (say stupid things)

4. To talk sense (say intelligent/reasonable things)

5. To wrap up the discussion (finish the discussion)

Lesson 9 reinforced concrete

Tasks before reading:

1. Find correct translation of English words. Make your own sentences with them

tensional property rigid durable fire resistant compressive property moisture exsposure fragile consideration homogeneous dense thorough obtain undergo shrinkage restraining medium induce resultant distribute cracking render innocuous guantity

свойство на сжатие хрупкий тщательный однородный подвергаться рассмотрение долговечный безвредный плотный усадка сдерживающий элемент жесткий направлять распределять трескающийся свойство растяжения подвергание исполнять, штукатурить количество результирующая доставать, получать огнестойкость влага

2. Compose correct word combinations. Guess their meaning

elastic tensional economic fire compressive restraining reinforced tensile resultant shrinkage

resistant concrete stress shrinkage properties medium quantity

3. Read the text. Find sentences having the main idea in each paragraph Reinforced concrete

Reinforced concrete is a combination of two of the strong-' est structural materials, concrete and steel, either of which is used separately. Consequently, the resulting material has the advantages of both.

Concrete has poor elastic and tensional properties, but it is rigid, strong in compression, extremely durable under and above ground, and in the presence or absence of air and water, it increases in strength with age, it is fire resistant, and suitable for any architectural or engineering forms.

Steel has great tensional, compressive and elastic prop­erties but is not durable below ground or if exposed to moisture, it loses its strength with age or exposure to high temperature. Steel is also fragile in appearance, giving an impression of weakness rather than strength. When strength is the most important consideration great care must be taken to produce a concrete that will be homogeneous and as dense as possible. Homogeneity is not possible without thorough mixing. To obtain strength and density, the aggregate must be sand and gravel, or crushed rock clean and free from or­ganic matter, and carefully graded from the smallest to the largest particles.

For general work the most suitable proportions of cement and aggregate are: 1 part cement, 2 parts sand, and 4 parts gravel or crushed rock.

Let us consider what is the effect of the addition of steel reinforcement to a concrete.

Steel is a material which does not undergo shrinkage on drying, and therefore the steel acts as a restraining medium in a reinforced concrete member; shrinkage causes tensile stresses in the concrete which are balanced by compressive stresses in the steel. Now the steel itself deforms under the induced stresses so that there must be a resultant shrinkage moment in a reinforced concrete member.

An economic quantity of steel, however, can be so disposed as to distribute the cracking under shrinkage stresses and thus render it innocuous. This is the problem for the designer of a reinforced concrete building, and it demands careful consideration on a proper design basis, both of the quantity and of the distribution of the reinforce­ment.

Tasks after reading:

4. Compare your variant of key-sentences to each paragraphs with these ones. Choose the best variant and prove your point of view. Add some more missing statements

1. Reinforced concrete is a combination of concrete and steel with advantages of both.

2. Steel adds properties that concrete has not got, but for homogeneity it is important to put some more aggregates into mixing.

3. Being restraining medium steel causes tensile stresses in the concrete which are balanced by compressive stresses in steel.

5. Finish these sentences. Add some more information from the text

1. Concrete has poor elastic and tensional properties but…

2. Steel has great…but it is not…

3. To obtain strength and density …

4. The steel deformes under the induced stresses…

5. The problem for the designer of a reinforced concrete building is…

6. Using statements from ex.4 and 5 speak briefly about reinforced concrete

Tasks before reading:

7. Find correct translation of Russian words. Explain their meaning in English

единицы балка монтировать, устанавливать перевернутый склад уменьшение скошенный резиновый стержень, брус сборный демонтирование каркас сваривать обеспечивать гладкий, ровный желоб, паз ребро балка тавровая ребристый плавить, выливать, отливать плиты заполнитель предварительно напряженный прут заанкеровать мастерская, склад отлитый на месте строительства фланец инвертировать, изменять пустой, полый гладкий желоб, паз наполненный воздухом отделять балка двутавровая скалывание ,срез сердцевина стержень стропило, балка, брус воспринимающий изгибающий момент

moment precast ribbed channel hollow i-beam slabs units core cast-in-place inverted filler beams assemble prestressed warehouse plain reduction smooth sloped groove inflated rubber dismantling bar cage shear rob weld anchor web cast flange invert shop secure detach joist t-section