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the roadway or adjacent property. In areas where land use is changing from agricultural to residential or commercial, peak flows will increase notably as the surrounding area is covered with roofs and paving.

Safety requires that water be rapidly removed from the pavement surface. In urban areas, the water runs into shallow gutters and thence into the inlets of underground drains. In rural areas, surface water flows beyond the shoulders to longitudinal drainage ditches, which have flat side slopes to enable vehicles leaving the pavement to recover without serious incident. Cut-off surface drains are used to prevent water from flowing without restriction down the slopes of cuttings and embankments.

Vertical drainage layers, formed from single-sized aggregate or special sheets called geofabrics and geomembranes, are used to prevent groundwater from seeping laterally into the pavement structure. In addition, a horizontal drainage layer is often inserted between base course and natural ground in order to remove water from the pavement structure and stop upward capillary movement of any natural groundwater. Underground drains can also be used to lower the groundwater level by both preventing water entry and removing water that does enter the pavement structure.

81. Give Russian equivalents to the following words without a dictionary. Use the words in the sentences and let your groupmates translate them.

82. Look through the text. Find the synonyms to the words below. Make up word combinations with the words.

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

Design; designedly; designee; designer; designing; designed.

Water; watered; waterer; watering; wateriness; waterless; watery; unwater. Layer; lay; layered; layering; laying; unlay; inlay.

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1.What features of the terrain interfere with good visibility for a

driver?

2.What is a minimum sight distance? What is one for the modern traf-

fic?

3.How may the night traffic safety be improved on the curves?

86.Translate the following words keeping in mind their suffixes and prefixes. Define their part of speech. Make up some wordcombinations using these words.

Vision, visible, visibly, visibility, visionally, visional, invisible, prevision.

Suffice, sufficient, sufficiency, sufficiently, insufficient. Safe, safely, safety, unsafe, unsafeness, save, saving, saver.

87.Find four different modal verbs used in the text. What is their meaning? Use them in your own sentences.

88.Fill in the correct preposition from the list below, then choose any three items and make sentences.

In, at, on, than, for, in, on, by, for.

… the road; … the maximum speed; … front of sb/sth; depending … the traffic speed; less … 1.500 m; to be ample … the vehicles; located … the cut; to improve … installing sth; an obstacle … good visibility.

89. Read these words and find them in the text below. Make your own sentence using 5 words from the list.

addition – добавка

adjoining land – прилегающая полоса земли curb – бордюр

dimension – размер, величина ditch – канава

drain – дренировать

drainage – дренаж, отвод воды edge – край

lorry – грузовик

normal – перпендикулярный

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outline – контур, очертание, схема plane – плоскость

roadway – проезжая часть дороги riding surface – ездовая поверхность road bed – дорожное полотно

road side – обочина, боковая полоса side track – разъезд

subgrade – земляное полотно surface – поверхность, покрытие traffic – уличное движение

traffic capacity of the lane – пропускная способность полосы traffic density – интенсивность движения

traffic lane – полоса движения

Roadway

The roadway is the name given to a part of a subgrade surface directly subjected to the traffic of vehicles. The roadway surface may be also called the riding surface. The roadway is directly joined to by the two roadsides. The roadway may be composed of natural ground, of the ground improved (strengthened) by different additions and forces or of a layer of different, mostly rock, materials, making the pavement. The roadway is separated from the roadsides by the curbs.

If there is no pavement, the roadway forms one monolithic structure with the roadsides.

The roadway together with the roadsides forms a road bed. The road bed is limited by the slopes on both sides. The lines separating the roadsides from the slopes are called the edges of the road bed. Beyond the limits of the roadway side drainage ditches may be situated. The side ditches are separated from the adjoining land by the outer edges of the ditches.

The cross-section of a highway is the intersection of its surface by a plane normal to its centre line. While designing the roadway it is first of all necessary to determine the width of the roadway, the kind of a road surface and its outline.

The width of a roadway depends upon the number of traffic lanes and the width of each of them.

The roadway consists of two traffic lanes and, serving two-way traffic, is mostly used on the motor highways. Each of the two traffic lanes is des-

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tined for the traffic in one direction only. The number of traffic lanes in its turn depends on traffic density.

Traffic density is a number of vehicles passing a definite section of the highway during a given unit of time. Maximum quantity of transport vehicles passing through one traffic lane of a roadway during a given unit of time (hour) is known to be a traffic capacity of the lane. Traffic capacity depends upon the rate and regime of traffic, type and condition of surfacing. Considering the destined designed traffic speed and the supposed maximum density per hour it is possible to design the number of necessary traffic lanes. The necessity often appears to have some traffic lanes in one direction when the traffic includes not only motor-lorries but cars with high speeds peculiar for them as well. In case one traffic lane serves the traffic in both directions the meeting and passing of the vehicles may be exercised by moving the vehicles out to a road side with one wheel, the speed being decreased by this. With one traffic-lane roadway and narrow road bed the side tracks are necessary.

The side tracks are made in the form of widening the roadside, road bed and the roadway. On the roadway having two traffic lanes with intensive traffic passing is exercised with some difficulties too. The high-speed motor-car has to exercise passing very often and thus its trajectory becomes very winding. That is why the designing of fouror six-traffic-lane roadways is necessary with intensive traffic and with different rate traffic flow. The four-traffic-lane-roadway ensures the comfort and traffic safety for high-speed motor-cars with more slowly moving motor-lorries available on the neighboring lane. There being no passing allows developing high speed and economizes fuel. The width of the traffic lane depends upon the dimensions of vehicles and their speed. The continuous developing of motor-traffic and the traffic rate (speed) called for the width of one traffic lane on trunk highways to be equal 3.5 – 3.75 m.

90. Look through the text and find answers to the following questions:

1.What is a roadway?

2.What materials may a roadway be composed of?

3.What does the width of a roadway depend on?

4.How is it possible to design the number of necessary traffic lanes?

5.When does the necessity appear to have some traffic lanes in one direction?

6.How wide is a traffic lane becoming nowadays?

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the fills the side ditches also remove water from the road bed and while constructing the road the earth from the ditches is used for making the fills.

The depth and the area of the cross-section of the ditch are determined depending on the amount of the water to be removed. With the little pervious soils by which the water is absorbed weakly the side ditches must be deeper than with the sandy loam soils absorbing considerable part of water.

Besides this side ditches may also drain the ground water partly if the water level is high and the bottom of the side ditch is placed below the water level. The depth of the side ditch considerably depends on the soil type of the road bed and at the same time the depth of the side ditch is considerably influenced by the width of the road bed since upon this depends the amountof water entering the ditch.

The depth of the side ditch is measured from the edge of the subgrade to the bottom of the side ditch.

The form of the cross-section of the side ditch depends on ground and hydrological conditions. The trapezoidal ditch with the inner slope of 1: 1.5 and the width of the bottom of 0.4 – 0.5 m is considered to be normal.

The trapezoidal ditches are made in the localities with the intensive surface water flow, with the ground water level near to the surface and in the impervious grounds.

The availability of the side ditches reduces the safety of the motor-car traffic essentially. The automobile got into a deep side ditch even at a low speed is wrecked. The usefulness of deep ditches in all the cases of subgrade structure is rather doubtful.

For the safety of motor-traffic the side ditch should be shallow and the slope into it must be comparatively flat with the simultaneous reducing of the depth to the amount necessary according to the ground and hydrological conditions.

97. Find the appropriate variants of translation for the following word-combinations from the text.

A.Along the sides of the road bed; the simultaneous reducing of the depth; in the cuts and small fills; from the edge of the subgrade; the depth of the side ditch; to drain the ground water; the form of the cross-section.

B.Дренировать грунтовую воду, в выемках и небольших насыпях, одновременное уменьшение глубины, параллельно краям дорожного

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полотна, глубина кювета, форма поперечного профиля, от границы земляного полотна.

98. Answer the questions.

1.What purpose do the side ditches serve in the fills? In the cuts?

2.Where are the trapezoidal ditches made?

3.Are deep ditches also useful?

4.What conditions influence the depth of the side ditches?

5.What is the relation between the absorbing properties of soils and the depth of the side ditches?

99.What new information have you learned from the text? Use the key words.

100.Read the text and answer the question:How does intersection influence road capacity?

Pic. 25

Intersections

Intersections reduce the capacities of the roads involved. Crossing traffic interferes with the free movement on either; road. On roads of the same dimensions the maximum capacity of the intersection for crossing

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traffic is theoretically equal to that of either road. Cross movements cannot be made at the same rate as direct movement, therefore the capacity of each road is less than 50 per cent, probably never more than 45 per cent, of the total capacity, or the total capacity of the intersection is not over 90 per cent of that of either one of two roads.

If the intersection is small, turning traffic will still reduce the capacity. The capacity of intersections is further effected by traffic regulations.

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

Peak, to lessen, through (adj), even (adj), joint, order, little.

102.Find adverbs in the comparative degree in the text. What subject do they refer to?

103.What facts from the text are given figures related to: 90; 55; 45.

104.Find in the text English phrases equivalent to the following ones.

Таких же размеров; регулируется правилами дорожного движения; движение в поперечном направлении; пропускная способность перекрестка; на такой же скорости; вовлеченных дорог.

105. What is the purpose of disjunctive strips? Read the text and check your answer.

Pic. 26

Disjunctive Strips

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On the trunk highways designed for the traffic with high speeds and on the roads with dense traffic it is necessary to take special measures for the safe meeting and passing of the motor-cars. The making of disjunctive strips is one of the essential measures taken with the purpose.

The principal purpose of this disjunction is not to allow any occasional moving of the motor-car out to the traffic lane of the opposite direction. The width of the disjunctive strip is destined from 1 to 5 m. For the designed speed of 120 km per hour the width of such a strip must be 3.0-3.5 m.

106.Find the Past Participles in the text and state their syntactic func-

tion.

107.Find the antonyms to the following words in the text.

Feeder (highway), light, common, dangerous, optional, direct.

108. Word construction. Translate the following words keeping in mind theirsuffixesandprefixes.Definetheirpartof speech.

Dense, densely, denseness, density, densify, densifier, densification. Junction, juncture, disjunctive, disjunctively, disjunction.

Oppose, opposing, opposed, opposite, opposition, oppositely.

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

Roadsides

The roadsides serve the following purposes:

1)to be the side stop for the pavement to avoid moving pavement material aside under the action of traffic;

2)to be safety lane between the pavement and the edge of the road bed to prevent the break downs at the time of the occasional moving of the automobile out of the pavement;

3)to be the place for the forced stop of the rolling stock in case of dis-

repair;

4)to be the place for the temporary disposition of materials for repairing the pavement;

5)to be the lane for the footpaths and bicycle-paths when the traffic is not dense;

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