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THE MOST IMPORTANT AND WIDELY USED BUILDING MATERIALS



Warming - up

1. Discuss the following:

• What materials are used in building construction?

2. Try to guess, the meaning of the following words. Use the dictionary if you need:

• physical properties of material

• a building

• a technology

• a construction

• a measure

• a proportion

• a component

• concrete

• cement

• a stone

3. Make up your own sentences with the words from Ex 2.

4. Read the text and find new words from the text.

   5. Find and translate all the sentences containing the following words:

· concrete

· component measuring

· construction

· technology

· proportion

· building

6. Reading for general meaning. Read and answer the following questions to the text:

• What is a modern technology?

• What materials' forms are very important in all masonry structures?

• What factors must the civil engineer consider?

• What can you tell something about the most accurate method of measuring proportions?

• What kind of material is the most widely used for the purpose of binding together masonry units such as a stone and a brick?

• What material is also known to be the most important com­ponent of concrete?

• What kind of material may be considered an artificial conglomerate of crushed stone?

• What can you tell about an important class of cement?

• What is high aluming cement?

• What materials are mostly used in Kazakhstan?

• What can you tell about building technology in Kazakhstan?

7. Read the text once more and complete the spidergram:

Building materials are very important in the construction. But it is more important for any designer to select and adapt such building materials of construction that will give the most effective result by the most economical means. In this choice of materials for any work of constructions many factors must be considered by the civil engineer. These factors include availability, cost, physical properties of materials and others.

Practically, all buildings materials have their advantages and disadvantages. That's why some materials are used most widely in building construction for the purpose of binding together masonry units. Among them are lime, gypsum and cement. Last material forms very important elements in all masonry structures, such as stone, a brick. Since the time of its introduction a gradual improvement of Portland cement quality has led to the elaboration of rapid hardening Portland cement, or «high early strength». Portland cement like other materials can be modified to suit a particular application. Later developments include low heat and sulphateresisting cements. The scope for such purpose - made cements has led to the development of an increasing variety such as high alumina cement, blast-furnace slag. They may be also white and coloured cements. Alumina cement has an extremely high rate of strength increase. Portland blast-furnace cement has greater resistance to some forms of chemicals.

So, cement is the most important component of concrete. Concrete is even less uniform than many other materials. Concrete may be considered an artificial conglomerate of "crushed stone, or similar inert material with a mortar". A mortar is a mixture of sand, screenings or similar inert particles with cement mid water. It is very important to know everything about proportions. The most accurate method of measuring proportions is to weigh the required quantities of each material. This may be done whether the proportions are based upon volumes or weights. This method is being extensively used in road construction and in many central mixing and in central proportioning plants. It is also widely used in large building constructions. Sometimes timber, steel and concrete are all vary over considerable ranges in the properties desired by the engineer. Even steel varies considerably in its microstructure.

8. Read the text again and complete the following sentences:

• Timber, steel and concrete all vary, sometimes over considerable ranges in the properties desired by...

• ...is even less uniform than many other materials.

• The designer must be able to select and... materials of construction that will give the most effective result by the most...

• The gradual improvement in... from the time of its introduction led to the elaboration of

• High alumina cement is a...

• It has an extremely...

• The most important building materials may now be considered to...

• A... of sand, screenings or similar...

• ...is a specific characteristic of this material.

 

9. Read the following statements and say whether they are true or false. Correct the false statements:

Lime, gypsum and cement are not the three materials most widely used in building construction for the purpose of binding together masonry units, such as stone, brick and as constituents of wall plaster.

• Cement is not the most important component of concrete.

• It has an extremely high rate of strength increase which is owing to the violence of the chemical reaction, accompanied by a considerable evolution of heat.

• The most important building materials are steel and concrete.

• Concrete may be considered an artificial conglomerate of "crushed stone, gravel or similar inert material with a mortar".

• A mixture of sand, screenings or similar inert particles with cement and water which has the capacity of hardening into a rocklike mass is called mortar.

• Timber, steel and concrete all vary, sometimes over considerable ranges in the properties desired by the engineer.

• Portland blast-furnace cement has greater resistance to some forms of chemicals.

Lesson 35-36

THE CHOICE OF MATERIAL

Warming - up

1. Discuss the following:

• What types of material do you know?

• What kind of material is used in Kazakhstan?

2. Try to guess the meaning of the following words. Use the dictionary you need:

• ordinary brick

• mechanical properties

• mass production

• reinforced concrete elements

• volume weight

• properties of the materials

• diverse properties

3. Match the following words with their Russian equivalents:

• mass production                • растягивающее напряжение

• reinforced concrete elements • хрупкий

• compressive loads             • теплопроводность

• bending loads                    • жесткий

• brittle                                • смола

• thermal conductivity           • сжимающие нагрузки

• volume weight                    • изгибающие нагрузки

• rigid                                     • железобетонные элементы

• wide application                 • приятный внешний вид

• construction site                  • широкое применение

• mechanical properties         • строительная площадка

  4. Read the text and find new words from the text.

  5. Reading for specific information. Read the text, choose a right word.

6. Read and translate about reinforced concrete.

Which {material, part) can be used to the best advantage for a particular part of the (building, hospital) depends on the kind of load to which it is subjected and on the shape of the part. The {development, increase) of the metallurgical and machine-building industries made possible (mass, water) production of prefabricated large-size concrete and reinforced concrete structural elements. It is the most advantageous to employ reinforced (concrete, floor) in such structural elements. Using prefabricated or precast elements, (builders, teachers) perform a considerable amount of building work at a factory where highly organized and mechanized {technological, mechanical) processes of production are practiced.

Reinforced concrete is a building (material, window) in which the joint functions of concrete and steel are advantageously utilized. Being brittle, concrete cannot withstand pensile stresses, and it cannot therefore be (used, cleaned) in structures subjected to tensile stresses under load. But if steel is introduced into concrete it changes the property of the (monolith, desk). Like any other (stone, light) material, concrete offers a good resistance to compressive loads.

In service two oppositely directed stresses appear in (reinforced, difficult) elements fully withstand bending loads. There are two kinds of reinforced concrete: with ordinary reinforcement and [concrete, paper) with pressed reinforcement. To reinforce ordinary concrete {structures, ideas) is to introduce steel rods in stretched zones of concrete elements. (Reinforced-concrete, easy) structures and elements are widely used both for residential houses and industrial {buildings, machines). Depending on the application of reinforced-concrete structures all kinds of (concrete, flag) such as heavy, light and heat insulating may be employed.

In many cases bricks are very satisfactory for using in the и (construction, school). (Bricks, doors) generally present a pleasing appearance and can be obtained with various qualities, (colours, meter s) and textures. Being of a high volume weight and high thermal conductivity, ordinary brick is not always satisfactory in a {building, medicine) practice. There are other kinds of bricks which are more effective, they are (light-weight, high volume weight) building bricks, hollow or porous bricks. Light-weight building bricks differ from ordinary clay bricks in a lower {volume weight, cost) Hid lower thermal conductivity, and are more economical than ordinary bricks.

One of the most significant {facts, children), dealing with both industries of synthetics and plastics. (Plastics, water) has appeared comparatively recently but, owing to their inherent valuable and diverse properties, has found a wide application in many industrial {fields, boxes) (machine-building, radiation, textile industry, etc.). ( Application, force) of plastics in the building field widens from year to year. In respect to physical and mechanical properties at a normal temperature of 20 °C all (plastics, bricks) are divided into rigid, semi-rigid, soft. In respect to the number of constituents plastics may be classified as simple and complex. (Plastics, things) Consisting of one polymer are referred to as simple. Thus, organic glass (plexiglass) consists of one synthetic resin. But in the building field we usually deal with (complex, metal) plastics, e.g. plastics consisting of a polymer and other components.

7. Read the text again and find the main idea of each paragraph.

8. Read the text once more. Recognize all the sentences, relating to a particular paragraph.

• The main characteristics of concrete.

• The chief principles of plastics classification.

• Factors that influence mass production of prefabricated large-side concrete and reinforced-concrete structural elements.

• New tendencies in the choice of building materials.

• The advantages of reinforced concrete.

9. Reading for general meaning. Read the text and answer the following questions to the text:

• Which material can be used to the best advantage for a particular part of the building?

• Is reinforced concrete a building material in which the joint functions of concrete and steel are advantageously utilized?

• Are there two (finds of reinforced concrete?

• Can you tell anything about one of the most significant facts about both industry land building?

• What are simple plastics?

 

Lesson 37-38

PROPERTIES OF MATERIALS

Warming -up

1. Discuss the following:

• The development of the metallurgical and machine-building industry made possible mass production of materials, did not it? Prove your own point of view.

• What advantages do all materials have?

2. Match the following words with their Russian equivalents:

• ensity                    • вес

• weight                    • количество

• a volume               • объем

• an amount             • плотность

• stiffness                  • жесткость

• rigidity                    • твердость

• a force                   • сила

• strength                 • прочность

3. Make up your own sentences with the following words:

density (плотность), weight (вес), volume (объем), stiffness (же сткость), to yield strength (поддерживать опору) fracture ( предел текучести), break (перелом, излом), ductility (ковкость) brittle(хрупкий), toughness (прочность), resistance (сопротивление), crack (трещина), creep resistance (устойчивость к ползучести), gradual (постепенный), permanent (постоянный), engine (двигатель).

4. Find a right word:

X S T I F N E S S I
Uu D E F O R M S T D
W I Z U R O O A R G
P E E R C W   Y L E
X I S T E E L O G H
W Y O O L L A Z I G
S S E N H G U O T N
f r a C t u r e h s

 

5. Read the text and find пет words from the text.

6. Read the text. Find and translate all the sentences, containing the flowing words:

• engine

• permanent

• change

• shape

• crack

• creep

• resistance

• gradual

• toughness

• brittle

• ductility

7. Reading for specific information. Read the text, choose a right world

8. Reading for general meaning. Read the text and answer the following questions to the text:

• Is density (specific weight) the amount of mass in a unit volume?

• Is it measured in kilograms per cubic meter?

• Is density important in any application where the material must not be heavy?

• Is stiffness (rigidity) a measure of the resistance to deformation such as stretching or bending?

• Is strength the force per unit area (stress) that a material can support without failing?

• Is toughness the resistance of a material to breaking when there is a crack in it?

• Is creep resistance the resistance to a gradual permanent change of shape?

Density (specific weight) is the amount of (mass, quality) in a unit volume. It is measured in (kilograms, distances) per cubic meter The density of water is 1000 kg/m3 but most (materials, kinds) have a higher density. Aluminium alloys, with typical densities around 2800 kg/m3 are considerably less dense than steels, which have typical densities around 7800 kg/m3. (Density, class) is important in any application where the material must not be heavy.

Stiffness (rigidity) is a (measure, glass) of the resistance to deformation such as stretching or bending. The Young modulus is a measure of the resistance to (simple, different) stretching or compression. It is the ratio of the applied force per unit area (stress) to the fractional elastic deformation (strain). (Stiffness, Density) is important when a rigid (structure, house) is to be made.

Strength is the (force, column) per unit area (stress) that a material can support without failing. The units are the same as those of stiffness, but in this case the (deformation, local) is irreversible. The yield strength is the (stress, point) at which a material first deforms plastically. For a (metal, water) the yield strength may be less than the fracture strength. It is the (stress,

metal) at which it breaks. Many materials have a higher (strength, work) in compression than in tension.

Ductility is the ability of a (material, column) to deform without breaking. One of the great (advantages, styles) of metals is their ability to be formed into the (shape , part) that is needed, such as car body parts. Materials that are not ductile are brittle. Ductile materials can absorb energy by (deformation, assignation) but brittle materials cannot. ■

Toughness is the (resistance, deformation) of a material to breaking when there is a crack in it. For a material of given toughness, the stress at which it will fail is inversely proportional to the square root of the size of the largest (defect, form) present. (Toughness, importance) is different from strength. For example, the toughest steels are different from the ones with the highest tensile strength. (Brittle, easy) materials have low toughness. For example, glass can be broken along a chosen line by first scratching it with a diamond. Composites can be designed to have considerably greater (toughness, flexible) than their constituent materials. The example of a very tough composite is (fiberglass, idea) that is very flexible and strong.

Creep resistance is the (resistance, part) to a gradual permanent change of a shape, and it becomes especially important at higher (temperatures, speeds). A successful research has been made in (materials, classes) for machine parts that operate at high temperatures and under high tensile forces without gradually extending. For example, they can be the {parts, ways) of plane engines.

9. Read the text and complete the spidergram:

10. Read the text again and complete the following sentences:

• Aluminium alloys, with typical densities around...are considerably less dense than steels, which have typical densities around...

• ...is important in any application where the material must not be heavy.

• The Young modulus is a... to simple stretching or compression.

• It is the ratio of the applied force per unit area (stress) to the...

• The yield strength is the stress at which a ...

• For a metal the yield strength may be which the stress at which it breaks is; many materials have a... tension.

• One of the great advantages of metals is... such as car body parts.

• Materials that are not ductile are...

• Toughness is the... of a material to breaking when there is a crack in it.

• ...is a measure of the resistance to deformation such as stretching or bending.

11. Read the following statements and say whether they are true or false. Correct the false statements:

• Density (specific weight) is not the amount of mass in a unit volume.

• Aluminium alloys, with typical densities around 3000 kg/m are considerably less dense than steels, which have typical densities around 7800 kg/m3.

• Density is not important in any application where the material must not be heavy.

• The Young modulus is a measure of the resistance to simple stretching or compression.

• It is the ratio of the applied force per unit area (stress) to the fractional elastic deformation (strain).

• Strength is the force per unit area (stress) that a material can support without failing.

• Many materials have not a higher strength in compression than in tension. Ductility is the ability of a material to deform without breaking.

• Toughness is the resistance of a material to breaking when there is a crack in it.

• It is measured in a kilogram per cubic meter.

12. Match the parts of the following sentences:

•Density                 • is the resistance of a material to breaking

                                  when there is a crack init.

• Stiffness             • is the amount of mass in a unit volume.

• Strength              • is a measure of the resistance to

                                      deformation such as stretching or bending.

•Ductility               • is the resistance to a gradual permanent

                                    change of shape.

•Toughness            • is the ability of a material to deform

                                      without breaking.

•Creep resistance      • is the force per unit area that a material

                                    can support without failing.

Lesson 39-40


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