The Properties of Building Materials
1.Materials that are used for structural purposes should meet several requirements. In most cases it is important that they should be hard, durable, fire-resistant and easily fastened together.
2.The most commonly used materials are steel, concrete, stone, wood and brick. They differ in hardness, durability and fire-resistance.
3.Wood is the most ancient structural material. It is light, cheap and easy to work. But wood has certain disadvantages: it burns and decays.
4.Stone belongs to one of the oldest building materials used by man. Its properties are mechanical strength, compactness, porosity, sound and heat insulation and fire-resistance.
5.Bricks were known many thousands of years ago. They are the examples of artificial building materials.
6.Concrete is referred to as one of the most important building materials. Concrete is a mixture of cement, sand, crushed stone and water. Due to its durability it is widely used in underwater structures.
7. Steel has come into general use with the development of industry. Its manufacture requires special equipment and skilled labour.
8.Plastics combine all the fine characteristics of building materials with good insulating properties. It is no wonder that the architects and engineers have turned to them to add beauty to modern homes and offices.
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9.All building materials are divided into three groups: 1) Main building materials such as rocks and artificial stones, timber and metals. 2) Binding materials such as lime, gypsum and cement. 3) Secondary or auxiliary materials which are used for interior parts of buildings.
10.We use main building materials for bearing structures. Binding materials are used for making artificial stone and for joining different planes. For interior finish of buildings we use secondary materials.
Пояснения к тексту
1.crushed stone – щебень
2.It is no wonder that – Неудивительно, что
3.turn to – обратиться
4.interior finish – внутренняя отделка
6. Перепишите вопрос и выберите правильный ответ.
What are main building materials used for?
1.for interior finish
2.for bearing structures
3.for making artificial stone.
Вариант 3
1. Перепишите и устно переведите следующие условные предложения. Напротив каждого из них напишите тип условия (реальное, маловероятное, нереальное.) Подчеркните предложение, для которого верно утверждение “The children played football at a distance from the house.”
1.The children will break the window if they don’t play football at a distance from he house. 2.The children wouldn’t have broken the window if they had played football at a distance from the house. 3.The children would have broken the window if they hadn’t played football at a distance from the house.
2. Перепишите предложения и переведите, обращая внимание на различные значения should, would.
1.You should work harder if you want to pass your exam. 2.It would be useful to have juice instead of coffee but I like it so much.3. He would sit for hours on the shore looking at the water.
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3. Перепишите предложения и переведите их, принимая во внимание, что инфинитивные и причастные обороты соответствуют придаточным предложениям.
1.A new type of crane having been tested, the builders put it into operation. 2.Unless treated, the water cannot be used for drinking and domestic purposes.
3. This is the branch of building engineering to be taken into consideration 4. The bearing capacity of the ground was too low for the builders to start the construction work of a tower block (высотный дом).
4. Перепишите предложения и переведите, обращая внимание на различные значения подчеркнутых слов.
1.The chief engineer is either at the office or at the laboratory. 2. As soon as you finish your calculations, we shall begin the tests. 3.All the calculations were made by means of an electronic computer. 4.In order to protect the surface from heat and cold it was covered with special substance. 5. The engine didn’t operate because of the bad fuel.
5.Прочитайте и устно переведите весь текст. Перепишите и письменно переведите 1-3 абзацы.
Reinforced Concrete
1.Reinforced concrete is a combination of two of the strongest structural materials, concrete and steel.
2.This term is applied to a construction in which steel bars or heavy steel mesh are properly embeded in concrete. The steel is put in position and concrete is poured around and over it, then tamped in place so that the steel is completely embeded. When the concrete hardens and sets, the resulting material gains great strength. This new structural concrete came into practical application at the turn of the 19th century. The first results of the tests of the reinforced concrete beams were published in 1887. Since that time the development of reinforced concrete work has made great progress. And the reasons of this progress are quite evident. Concrete has poor elastic and tensional properties, but it is rigid, strong in compression, durable under and above ground and in the presence or absence of air and water, it increases its strength with age, it is fireproof.
3.Steel has great tensional, compressive and elastic properties, but it is not durable being exposed to moisture, it loses its strength with age, or being subjected to high temperature. So, what is the effect of the addition of steel reinforcement to concrete?
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4.Steel does not undergo shrinkage or drying but concrete does 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. For getting the best from reinforced concrete the following consideration should be kept in mind:
1. For general use the most suitable proportions of cement and aggregate are: 1 part cement, 2 parts sand and 4 parts of gravel.
2. Only fresh water free from organic matter should be used for reinforced work. Sea water is not allowed.
3. Homogeneity of the concrete is a very important requirement. Steel constructions with reinforced concrete have become the most widely used building materials invented in centuries.
Пояснения к тексту
1. put in position – укладывать, устанавливать
2.the resulting material – полученный в результате материал
3.at the turn of the century – в конце века
4.restraining medium – сдерживающая среда (средство)
5.keep in mind – помнить
6.fresh water – пресная вода
7. free from – не содержащий
6. Перепишите вопрос и выберите правильный ответ.
Why do we add steel to reinforced concrete?
1.to balance tensile stresses in the concrete.
2.because concrete loses its strength with age.
3.because it doesn’t undergo drying.
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СОДЕРЖАНИЕ
1. Программа ……………………………………………………………………..1
2. Образцы выполнения заданий ……………………………………………….2
3.Контрольное задание №1………………………………………………………3
4.Контрольное задание №2 ……………………………………………………...9
5.Контрольное задание №3 ……………………………………………………...14
6.Контрольное задание №4 ……………………………………………………...20
7.Контрольное задание №5………………………………………………………25
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