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For ensuring the motor-traffic the road pavement must possess the following qualities:

1)durability of entire construction for avoiding sags and breaks under the pressure of wheels;

2)durability of the upper layer for avoiding its quick wear;

3)smoothness of the pavement necessary for the rolling of motor-car without impacts and swinging of the automobile body, with the minimum resistance to rolling;

4)the roughness of the surface for the higher value of the coefficient of cohesion of the wheel with the surface;

5)the quality to produce no dust (dustlessness).

For the sake of the traffic safety and comfort the cross-section of the roadway surface is desired to approach horizontal lines as much as possible. Nevertheless, for the transversal drainage the sufficient cross-section of the pavement surface is necessary.

The (outline) form of a roadway and its cross-section must satisfy both requirements. The firmness of the vehicle on the sloping (inclined) roadway surface depends upon the cross-section value, condition of the pavement surface and traffic speed. On the pavement with the considerable cross-section vehicles tend to occupy the middle of the pavement where thus the traffic concentrates. This promotes wear of the middle part of the pavement.

56.Look through the text and find –ing forms used for describing different processes concerning highway pavement.

57.Find the synonyms to the following words in the text:

influence, plan, deformation, mark out, driving, whole, frail, tread, below.

58.Find the antonyms to the words below (they are in the text). Slow, firm, underneath, lower, dry, increase, unpleasant.

59.Form the words denoting different qualities of the pavement. List the suffixes used for it.

Durable, smooth, to distort, to press, to resist, to compress, plastic, dustless.

60. Match these descriptions with the names of different road layers.

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2.How do you understand the term wear?

3.Why is the determination of the possible wear in the course of the time important?

Road Surfacing Wear

When the road is in service there takes place the influencing of different factors upon the road surfacing and this causes the surfacing getting gradually thinner. The first factor causing the decrease of surfacing thickness is the influence of traffic, and the second factor is the influence of atmosphere.

The loss of the material of the road surface while in service and the decrease of its thickness is termed wear. The surface wear is uneven on the surface area.

The weakest sections which had different defects in the process of constructing or repairing are the most quickly worn out. As a result of the unevenness of the wear there appear some roughness and potholes on the road. The most even wear is observed with the black surfaces.

The determination of the possible wear in the course of time is rather important for the proper organization of the exploitation of the road because such determination gives the possibility to fix: 1) the amount of work and the quantity of materials necessary for ordinary repairs; 2) the terms of the average and capital repairs, which may appear necessary for restoring the evenness of the surfacing.

The determination of standards or the creating of formulas of wear requires systematic studying of service of the exploited roads during the long period of time.

surfacing – 1) выравнивание поверхности; 2) обработка поверхности; 3) покрытие дорожной одежды

wear – износ

wear out – изнашиваться, истираться

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

A cause – to cause; an influence – to influence; a decrease – to decrease; wear – to wear; a surface – to surface; repair – to repair.

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

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1)the necessity of draining the water which can penetrate into the trough if the revetment is permeable;

2)the easiness of the dirt being carried, from the roadsides to the revetment.

The sickle shaped profile has also its own advantages and defects.

Principal Constructive Layers of Road Revetment. There are two groups of constructive layers in a road revetment – surfacing and artificial foundation.

The surfacing may consist of one or more layers sometimes of material of different character and durability.

The layers are directly subjected to traffic and must defend all the construction from the influence of climate factors and from penetrating water first of all. In the consequence with this any surfacing must have smooth, but not slippery, dustless and impervious surface, stable enough to resist the influence of the load in any period of time.

carriage way – проезжая часть revetment – одежда (дорожная) road side – обочина, боковая полоса sickle-shaped – серповидный subgrade – земляное полотно trough profile – корытный профиль permeable – (водо)проницаемый

68.Word construction. Translate the following words keeping in mind their suffixes and prefixes.

Strong, strongly, strength, strengthen, strengthened, strengthening. Construct, constructive, construction, constructor, constructing, constructible, reconstruction.

Permeate, permeating, permeation, permeable, permeability.

69.What constituents does this compound word consist of? Give other examples of compound words, using these and other roots.

sickle-shaped

70. Look through the text and find the words formed from these ones.

What parts of speech do derivative words belong to?

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type of construction and on the contrary it is necessary to choose types of surfacing and to design constructions, taking into account the specific properties of the materials, projected for the utilization. That is why the problem of providing the construction with the road building materials is to be put to one of the first places while building the road revetment.

There appears the necessity of creating the industry of road building materials: mainly the broken stone, different mineral material mixed with organic binders (black, cold asphalt, mastic etc.) and binders themselves - mineral binders (cement, lime) and organic binders (bitumen, tar, emulsion of tar).

The quality and economy of the work greatly depend upon the proper selection of mechanisms and upon the proper organization of work.

The great problems standing before the motor highway constructors will appear unfeasible without mechanization of all the processes requiring much labour expenditure.

But equipping the roadbuilding with the necessary perfected machinery is not sufficient if the latter is not rationally utilized, or if there is no co-ordination in the efficiency of different mechanisms. It will not give the desirable effect if there is no systematic daily control of the utilized materials, ready-made constructions and without the exact following of the fixed technological process.

Only following all the above mentioned conditions will make it possible to secure the high quality of the road revetment with minimum expenditure for its construction and to put it into operation in the shortest time possible.

72. Answer the questions:

1.What is the percentage of cost of road revetment in the whole cost of highway?

2.What must be taken into consideration while determining the class of road revetment?

3.What factors influence the durability of surface and economy of road revetment construction?

4.What is necessary to do for the road construction requiring the large amount of the transportation work?

5.How may the high quality of the road revetment be achieved with minimum expenditure?

73. Translate the following words taking into consideration the meaning of the prefixes:

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impossible, irrational, predetermine, redistribution, reconstructed, irrespective, unfeasible.

74. Word construction. Translate the following words keeping in mind their suffixes and prefixes.

Provide, provided, provision, provident.

Necessity, necessary, necessarily, necessitate.

Utilize, utilization, utilizable, utilizer, utilized, utilizing.

Quality, qualitative, qualify, qualification, qualified.

75. Complete the following sentences, using the information from the text:

1.Choosing the type of surface and construction of the road revetment for the new road as for the reconstructed one it is necessary to realize … .

2.The durability of the foundation to some extent … .

3.Proper placing the grounds in the subgrade body and their proper consolidating are … .

4.The great problems standing before the motor highway constructors will appear unfeasible without … .

5.One must take into account the redistribution of moisture which occurs as a result of … .

6.But equipping the road building with the necessary perfected machinery is not sufficient if … .

76. What types of surfaces are there? Read the text and check your answer.

Road Surfaces in the USA and Canada

There are concrete highways in parts of the US, especially the Interstates. Canadian highways are asphalt/blacktop/tar/whatever you want to call it. Reason is that concrete expands and contracts to such a degree that it'd self-destruct during a Canadian winter.

The joins between the slabs of concrete often cause a rhythmic thump as you drive which does the tyres and suspension no good at all.

The vast majority of roads in the USA and Canada are paved. However, there are some unpaved minor roads.

Most car rental companies include clauses in their rental agreements prohibiting the use of their vehicles on unpaved roads.

Unpaved roads are usually clearly marked on maps, often by dashed lines. Unpaved roads may also be referred to as gravel roads, dirt roads or

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