ROAD BUILDING MATERIALS

lents to the following words without a dictionary. Make up your own word-combinations or sentences with them.

Mechanical, physical, technological, chemical, compression, constant, process, correct, laboratory, experimental, industrial, real, initial, re-

3. Find the synonyms of these words in the text below.

Capability, intended, to be implemented, proper, use, deep, to gain, to condition, an aim.

4. Translate the following words keeping in mind their suffixes and prefixes. Define their part of speech.

Conduct, conductance, conducting, conduction, conductive, conductivity, conductor.

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Utilize, utilizable, utilization, utilize, utilitarian, utility, utilized, utilizing, reutilize.

Character, characteristic, characterization, characterize, characterizer, characterless, uncharacteristic.

5. Analyze the models of word formation. Read and translate the

of this material to resist the action of outer mechanicalИforces. Under the influence of mechanical forces the material in road structures undergoes compression, shear, bending, tension and torsion.

Physical Properties of the material are determined by the physical constants. Physical properties include weight, compactness, water properties, weather resistance, heat conductivity, fire-resistance, sound conductivity etc.

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Technological properties are such properties which stipulate the attitude of the material towards the technological processes.

Chemical qualities of the material define the ability of the material to the chemical interaction with other substances.

The quality and durability of the road revetment depend to the consid- Сerable extent upon the correct choice of the road building materials.

To make a correct choice of the road-building material it is not only

necessary to know its properties but also to have a notion of how these properties will remain for some time under a given traffic density of the road and in such natural conditions in which the structure will work.

haveиthe judgment about the capability of the material to resist the influence of natural factors and alongside with this it is important to know about how this material can save money. Usually the defining of the technical properties of the road-building material destined for some or other structure is done by means of the corresponding tests, which may be fulfilled under field conditions, in a laboratory and on the experimental road.

Besides the durability in the true sense of this word it is necessary to

Naturalбstone materials are the oldest representatives of the building materials, but the rationalАutilization of stone for different building purposes became possible only from the second half of the XIX century as a result of numerous scientific researches and the studying of the industrial experience of the utilizing of stone materials in different natural regions.

granite was very often imported fromДSweden, marble - from Italy and so on. Only later the prospecting of minerals and researching of stone materials began being developed.

The works of N. A. Bolelyubsky on the research of frost resistance of stone materials, the works of professors I. H. Maluga, N. K. Lakhtin and

others were of extremely great importance.

In tsarist Russia the knowledge of natural riches of the country was

quite insignificant. This is proved at least by the fact that such material as И

Thanks to the works of academicians D.S. Belyankin, F.U. Levinson - Lessing, V. A. Obruchev and other scientists now we know and utilize our riches of stone materials.

Stone materials are characterized by comparatively great strength and durability. Stone materials are widely used in road and bridge building;

they are also used for making stone elements of artificial structures, for constructing stone road surfacing, they serve as a stone frame for the ma-

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jority of cement-concrete and asphalt-concrete mixtures; stone material is used for draining facilities and many other road structures.

Natural stone material is nothing else as rocks, which are organic part of the crust from the upper layers of which they are obtained in the form of solid, massive boulders of unequal size and shape or in the form of loose accumulation of disintegrated rock formations of different size. In order to become the real building material the massive rocks undergo mechanical

СIn the process of manufacturing artificial articles the initial raw stuff undergoes more or less profound changes and acquires some new technical

treatment.

Artificial rock materials are produced at the mills of the raw stuff of

the natural origin or of the factory waste.

properties.

Out of numerous artificial stone articles road paving brick, common

pavement and sidewalk surfacing, floors, foundations, hydrotechnical,

1.What technical properties of road-buildingИmaterials do you know?

2.What is necessary to make a correct choice of the road-building materials?

3.Where may the defining tests of the road-building material be ful-

filled?

4.What are the oldest representatives of the building materials?

5.Where are stone materials widely used?

6.What artificial stone articles are used in road building?

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7. Complete the sentences using information from the text.

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9. Learn to recognize international words. Give Russian equivalents to the following words without a dictionary.

Natural, ceramic, material, characteristic, gravel, mineral, massive, granite, technical, silicate, local, method, mechanization, economize, front,

Сcentralized, role, rational, transportation, utilize.

10. Find the word with the most general meaning in each line.

Brick, material, gypsum, glass, metal.

Clays, loamy soils, grounds, sandy soils.

Cement, bitumen, tar, lime, binder.

Bridge, culvert, road structure, surface.

Road building materials

Road buildings need great amount of different materials which are necessary for constructing the road subgrade, revetment, artificial constructions, technical and civil road buildings and etc.

The most principal road materials are grounds, stone material and

Sands are used for making the underlayer of the foundation of road surface, for drainage facilities. Sand is also used as a component in groutings, cement and asphalt concrete.

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Stone materials (natural and artificial) having the leading role are used for making road surfaces, bridges, culverts and other road structures.

Wood materials are used mainly for constructing artificial structures, different buildings etc.

Besides this, road building widely uses organic binders (bitumen, tar), Сmineral binders (cements, lime), metals and other materials.

Bitumen with using organic binders is generally used for making road surfacing.

and partially for road-bridge construction.

Brick, gypsum, slag material, paints, glass, roofing material and others areиalso used for constructing different technical and civil road buildings

The cost of material, mainly its haulage makes the principal part of expenditure for the road building (about 60% or even more). Hence it becomes clearбhow important the rational using of the materials and reduction of haulage expenditure are and how necessary it is to utilize the local materials wherever possible.

Maximum mechanization of getting materials, their transportation, mechanization of building jobs, application of perfect road constructions, advanced methods of work with utilization of local building materials on large scale are the main ways of reducing the road building cost.

As to the origin and method of getting road building materials are di-

give material the necessary size and shape, and sometimes only some definite state.

Artificial materials are such materials which are specially made of raw staff having the natural origin or of factory waste by mechanical or chemical influence. According to the origin, methods of obtaining, characteristics and application road building materials may be divided into the following groups:

1)ground materials: clays, loamу soils, sandy soils, etc.;

2)natural stone materials: a) massive granite, sandstone, limestone and others; crushed materials – broken natural stone; grinded material - stone powder; b) loose material – sand, gravel;

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3) artificial stone materials: a) ceramic materials (articles of burnt clays) paving brick, tiles, agricultural pipes etc; b) silicate articles: brick, blocks, c) slag materials and clay articles – stones, broken stone, blocks, d) stone casting;

4) mineral binders: cements, lime, gypsum etc; С5) concretes using mineral binding materials – cement-concrete, con-

crete articles (slabs, blocks, etc.);

6) organic binders – bitumen, tar, etc;

7) concretes, using organic binding materials – asphalt concrete, tar concrete and concrete articles;

8) materials and articles of wood;

9) metals and metal alloys: a) metallic materials: cast iron, steel, non-

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14. Translate these words depending on their part of speech. Which of them were used in the text?

A cost – to cost; free – to free; the ground – to ground; a state – to state.

СMake up your own word-combinations and sentences with these words.

15. Complete the sentences using the text.

и1. The grounds serve as … of the road to be built.

2. Bitumen with using … is generally used for making road surfac-

ing.

3. The cost of material, mainly its … makes the principal part of expenditure forбthe road building.

4. As to the origin and method of getting road building materials are divided into … and … .

5. Natural materials may be used for building purposes without … . 6. Building materialsАto be found in the place of construction and ob-

tained to satisfy construction needs are called … .

16. Answer the questions.

1.What are the most principal road materials?

2.Where are sands used?

3.What advantage does utilizing the local materials give?

4.What are the main ways of reducing the road building cost?

5.How may road building materials be divided?

6.What natural and artificial stone materials are used in road construction? Д

17. Make up a dialogue on the topic. OneИof the partners is a highway engineer. He answers the questions of the other dialogue participant, who is a student trying to get as much information as possible. Use the following conversational formulas:

a) For a student:

Good morning! (Good afternoon! Hello!)

Let me introduce myself. My name is ______.

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constructions (in concrete).

Representatives of mineral binders, known to the mankind from the ancient times, are clay, gypsum and lime.

Mineral binders are such materials which while mixing with water are capable of hardening, turning from liquid or paste state into hard stone-like state, most of them increasing their durability in the course of time.

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Binding materials in most cases are manufactured at plants and are being turned out in the form of powder.

Depending on the conditions of the hardening all the binding materials may be divided into two large groups:

1) such binding materials which after mixing with water are capable Сof hardening only in the air are called air binders; the characteristic repre-

sentatives of this group are air lime and gypsum;

2) such binding materials which after mixing with water are capable of hardening not only in the air but underneath water as well are called hy-

draulic binders.

иFor road surfacing in Russia we use ordinary silicate cement «400» and «500» trade mark cement, but in this case the silicate cement must have minimumбslump while hardening and minimum expansion while being moistened (swelling), it must have sufficient mechanical durability not only when in compression but when in tension and bending as well.

Typical representatives of this group are silicate cement and other ce-

ments.

Except this, such cement must resist rubbing out to a definite extent and possess little permeabilityАto water.

It must also be capable of changing the volume evenly while drying. Satisfying these requests is achieved by regulating mineralogical

composition while manufacturing silicate cement.

stances, consisting of the mixture ofДvarious hydrocarbon combinations. The function of organic binding material in the road surfacing is to

Organic Binders

The principal representatives of organic binders are natural and petro-

leum bitumens and tars.

envelop and bind separate stone or ground particles to make monolith of them.

These materials represent black viscous liquid and plastic-hard sub- И

Bitumen and tar materials impart to the road-surfacing plasticity and great resistibility to different atmospheric and mechanical influences side by side with the properties of solidity and impermeability to water which are generally characteristic to road surfacing treated with binders.

Thus organic binders differ from other materials by some important technical properties, and that is the reason of the organic materials being widely used in road construction.

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Road surfacing plasticity conditioned by bitumen and tar material reduce surfacing wear caused by the influence of transport and thus raises the term of surface service. Besides this the availability of such materials in road surface softens the surface vibration and reduces the communication of the oscillatory movements resulting from the dynamic stresses to the adjacent structures.

The general drawback of organic binding materials lies in the fact that they change their binding properties depending on temperature which makes the mechanical properties of the road surfacing unstable.

20. In the text “Organic binders” find the nouns made from adjectives by means of the suffix -(i)ty. Translate them. What is their

21. Are the sentences belowДtrue or false? Correct wrong statements. Begin your answers with these expressions:И

That’s right. Exactly so. Precisely so. I agree with it. I’m afraid that/s not correct. Nothing of the kind. No, that’s not right.

1.Mineral binders are such materials which while mixing with water turn into liquid or paste state.

2.Depending on the conditions of the hardening all the binding materials may be divided into three large groups.

3.Hydraulic binders are capable of hardening underneath water.

4.The difference of organic binders from other materials by some important technical properties is the reason of their limited using.

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5. The general drawback of organic binding materials lies in the fact that they are unable to change their binding properties depending on temperature.

6. Road surfacing plasticity conditioned by bitumen and tar material reduces the term of surface service.

С22. Read and study the following words, make up your sentences with them.

aggregate – заполн тель, инертный материал; совокупность beamи– балка

fluctuation – коле ан е freeze – замерзать

humidity – влажность impact – толчокобъем, удар

reinforced concrete – армированный железобетон resist – сопрот вляться

23.In each line Аfind the word with the most general meaning

1.Foundation, girder, floor, construction,Дarch, pillar. .

2.Sand, aggregate, cement, water, gravel.

3.Bending, force, settling, tension, friction.

24.Find nouns with suffixes -tion, -sion,И-ion in the text.

25.Learn to recognize international words. Give Russian equiva-

lents to the following words without a dictionary. Make up your own word-combinations or sentences with them.settle – усаж ваться, уменьшаться в е

Specially, rationally, construction, silicate, temperature, general, dispersion, atmospheric, factor, service, stress, compact, deformation.

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26. Read the text and answer the questions after it.

Cement Concrete

The specially and rationally selected, consolidated and hardened mixture of broken stone (or gravel), sand and cement paste is called concrete.

СBefore consolidating and hardening the aggregate of broken stone, sand, cement and water bears the name of concrete mixture.

Concrete is widely used in building for making foundation, reinforced concrete constructions, columns (pillars), girders (beams), floors, arches and bearing constructions.

иThe concrete for road surfacing is made with application of silicate concrete only.

In contradiction to ordinary concrete and reinforced concrete constructions, the concrete of the road surfacing is in the most difficult conditions of work: it бfeels the repeated impact influence from vehicle movement, suffers wear because of friction etc.

The concrete in the road surfacing undergoes also the bending force. In case of settling or changing the temperature and humidity the concrete undergoes the tension Аforce too.

Uneven humidity of the concrete slab as far as the thickness is concerned, drying out on top and moistening from below, create the additional stresses within the concrete.

The general peculiarity of theДconcrete work in the road surfacing is the dispersion of action of forces in the great number of places. At last the direct influence of atmospheric factors (moistening and drying out, the repeated freezing and thawing out, fluctuation of temperature etc.) create the most unfavourable conditions of service for the road concrete.

To be capable of resisting the forces arisingИin the road surfacing at the time of speedy movement of automobiles and when heavy loads are carried along the road, cement concrete must possess high compression, tensile and bending strength, it must be significantly hard to resist wear, must possess toughness to resist influence of impacts and at last it must be as compact as possible to ensure its frost resistance; besides this the concrete must possess properties ensuring the least degree of settling and temperature deformations.

1.What does concrete consist of?

2.What concrete is used in road surfacing?

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3. Why is the concrete of the road surfacing in the most difficult conditions of work?

4. What forces does the concrete of the road surfacing undergo? 5. What properties must the cement concrete possess?

С27. Study the following words.

cast – литой, отлитый curb – бордюр

float – глад лка, мастерок fluctuationи– колебан е hydroinsulating – г дро золяционный levelling – выравн ван е

petroleum – нефть

putty – замазкаб slipperiness – скользкость

solution – раствор

tenacious – вязк й, прочный, крепкий

viscous – вязкий, липкийА waterproofness – водонепроницаемость

28. Learn to recognize international words. Give Russian equivalents to the following words withoutДa dictionary. Make up your own word-combinations or sentences with them.

Limits, mastic, stability, elastic, bitumen, asphalt, special, character, plastic, absorb, amplitude, compactness, consistence, organization, mechanization, classify, cylinder. И

the text.

30. In what meaning are the following words used in the text?

Composition:

–a piece of writing undertaken as an academic exercise in grammatically acceptable writing; an essay;

–the parts of which something is composed or made up; constitution.

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ing of stresses of different character and of different amount within the material. That is why the concrete must offer sufficient resistance to compression, tension, rubbing and besides this it must possess plastic and elastic properties, absorbing these stresses and causing no damage to the surfacing.

СMechanical properties of asphalt concrete may change depending on temperature. That is why it is necessary that at given amplitude of fluctua-

tion of temperature the change of mechanical property is within the certain limits, in other words it is necessary that asphalt concrete possesses sufficient temperature stability. Simultaneously with the mechanical influences the asphalt concrete in the road surfacing undergoes destructive influence of atmosphere factors (water, air etc.).

quality.и

To achieve the minimum influence of these factors asphalt concrete is to possess sufficient compactness and to consist of materials of proper

mixtures is distributingбthem in a layer of uniform thickness over the road bed foundation and consolidatingАthem with the help of rollers (rigid type) or levelling with the help of a wood float (cast type of mixture). According to the chosen method of treatment the mixtures must be of proper consist-

The necessary technological property of asphalt concrete mixtures is easiness of treating these mixtures. The main method of treating asphalt

ence at the operating temperature. Thus the most principal technical properties of asphalt concrete are mechanical durability, compactness and easiness of treating.

In some cases asphalt road surfacingДis required to be more rough than usual to reduce slipperiness or to have definite colour for the purpose of making disjunctive strips, curbs, etc.

Except above mentioned properties which are considered to be the main properties some special qualities are sometimes required of asphalt

concrete. И

Cost of asphalt concrete mixture must be low. It depends on the com-

ponents cost (especially on the expenditure of the most expensive materials of the mixture - bitumen and mineral powder). and on the production factors. Utulizing local materials, rational work organization, full mechanization of production process, advanced methods of work are the ways of reducing the asphalt concrete mixture unit cost.

Cold asphalt concrete mixtures differ from hot ones because they may be applied at the normal temperature (15° – 25°) without being heated.

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Cold asphalt mixtures are classified according to the nature of the component materials and the method of preparation.

Depending on the nature of binder cold mixtures may be asphalt mixtures (with application of bitumen) and tar mixtures (with application of tars).

СWhen utilizing asphalt rocks it is possible to get natural cold asphalt materials. Artificial mixtures are produced by means of the application of crushed stone materials and liquid bitumen, and tars or emulsions.

Mechanical properties of cold fine-grained asphalt depend on binder viscosity, thickness of enveloping film, properties of stone frame and mixture compactness. Mechanical properties of cold asphalt mixtures are determined according to resistance the cylinder shaped patterns of h = 50 mm, d = 50 mm offer to compression.

coherency – связность, сцепление ground asphalts – грунт–асфальт loamy – глинистый

powdered soil – пылеватый грунт saturate – насыщать, пропитывать

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34. Explain the name of this building material, then read the text and check your explanation.

Ground asphalt

Ground asphalts are asphalt mixtures which comprise natural soils as Сmineral materials sometimes with the addition of sand or gravel and bitu-

men or tar as a binder.

Utilisation of natural (clayey) loamy and powdered soils as road building materials for making road surfacings is difficult because their mechanical properties are not constant under variable humidity and sand is inconvenient to use because it possesses no coherency.

Some soils are very unstable, grinding to dust easily when dry or quickly turning to mud when wet and hence the roads are difficult to maintain.

36. Translate the following words keeping in mind their suffixes and prefixes. Define their part of speech.

Mix, mixable, mixed, mixer, mixing, mixture, premix, unmixed.

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Stable, stability, stabilize, stabilized, stabilizing, unstable, unstabilized.

Vary, varying, variable, variability, variant, varied, unvarying.

37. Read the text to answer the question “What are the main

Сdom of tar concrete are slabs, chesses and pipes. Slabs and chesses are used as building materials for paving the roadways, streets, bridges, surfacing between tram rails, and sidewalks. For making the asphalt concrete

kinds of articles made of asphalt concrete?”

Asphalt concrete articles

The principal kinds of articles made of hot asphalt concrete and sel-

tumenиexcluding, must be chosen in the accordance with such technical requirements as for common asphalt concrete used in hot state.

slabs only fine-grained asphalt concrete and sand asphalt are used. The ma-

terials composing the asphalt concrete mixture used for making slabs, bi-

slabs it is necessaryбto take into consideration the peculiarities of making (moulding) slabs and their work in surfacings.

While choosing the properties of bitumen used for asphalt concrete

А 1. a) The road was in a pure stateД.

38. Read the sentences, define the initial form of the words in

bold and their part of speech. Then find relevant meanings of these words in a dictionary.

b) The former colony became an independent state.

b) Bridges and sidewalks are often paved by chess.

3. a) The principal of our school is a rather young man.

b) The principal sphere of our activity is development of new building materials.

4. a) This article was published in “The Times”.

b) The shop sells articles of clothing.

5. a) Many plants have medicinal properties.

b) The police found some stolen property hidden in the thief’s house.

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39. Complete the sentences using information from the text.

1. Slabs and chesses are used as building materials for paving … .

2. Only fine-grained asphalt concrete and sand asphalt are used for making … .

С3. The peculiarities of moulding asphalt concrete slabs must be taken into consideration while choosing … .

4. Slabs, chesses and pipes are seldom made of … .

40. Read the additional text and give its short summary. Try to

making.иAt present wood is one of the most widespread building materials in different fields of national economy. The total area of woods in Russia occupies 30% of the whole territory of the country.

guess when this text was written. Why do you think so?

Use of wood

Except the materials already described we also use wood -for road

Great reservesбof wood, the comparatively simple method of exploiting large forests, easyАmachinability of wood and the significant development of the technique of wood working are the main reasons of wood being widely used in engineering. Wood as building material possesses some valuable properties. Being highly resilient and durable, easily worked wood has little volumeritrical weight which makes transportation easier and conditions the low weight of wooden constructions. But these advantages may be reduced to some extent by some negative properties char-

depending on humidity; some speciesДof trees have also insufficient hardness; when dry wood can produce cracks; wood undergoes rotting and damage by insects; wood catches fire easily.

acteristic for wood.

Wood is used for making bridges, pipes, blocks for road surfacing. Buildings and other structures may also be made of wood.

The main defects of wood are: the changing of mechanical properties И

41. Roads from coffee grounds? Is it a myth or reality? Watch the video http://www.ccinnovations.ca/clearinghouse/1149/roads-from- coffee-grounds/ and express your opinion.

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