Renewed, multilayer, stresses, loads, roughness, roadbed, porous
1. The pavement is designed in the form of ________ structure.
2. The ________ induced in the pavement attenuate with the depth.
3. A wearing course is periodically ________ as it wears out.
4. Surface treatment is used for increasing the ________ of polished surfacing.
5. The pavement base is a strong bearing layer of stony materials which distributes the wheel ________ over the sub-base.
6. ________materials are introduced in the sub-base which drains away excess water.
7. The subgrade comprises the thoroughly compacted upper layers of the ________.
Language focus
7. Match the words with their synonyms:
a). operation, to induce, to determine, rigid, impact, to comprise, to protect, section, to satisfy the requirements, agent, to term, thoroughly, to occur, to regard, to employ.
b). tough, substance, to decide, work, to consider, to cause, to meet the requirements, to use, to defend, stretch, to involve, carefully, influence, to take place, to call.
8. Match the words with their antonyms:
a). upwards, external, roughness, heterogeneous, reduce, fine.
b). internal, increase, smoothness, coarse, homogeneous, downwards.
9. Form nouns from the following words:
to treat-…..; rough-…..; to penetrate-…..; to resist-…..; to drain-…..; to compact-…..; to distribute-…..; smooth-…..; stable-……
10. Fill in the correct prepositions:
1. to consist … sth (something); 2. to subject … sth; 3. … accordance … sth; 4. to treat … sth; 5. to depend … sth; 6. … addition; 7. … the same time; 8. to be designed … sth.
11. Fill in the blanks with English equivalents:
1. The surfacing provides (гладкость поверхности и высокий коэффициент сцепления). 2. (Слой износа) is not taken into account in calculations. 3. The surfacing which is made of weak materials (обрабатываeтся) with organic (вяжущими). 4. To make the surfacing (водонепроницаемым) it is covered with a thin (защитным слоем). 5. (Основание дорожной одежды) is designed (чтобы распределить нагрузку колёс) over the sub-base. 6. The pavement base (может быть насыщено) by water drawn upwards from the roadbed. 7. (Подстилающий слой устойчив к влаге), it is designed of (пористых материалов). 8. The sub-base is also termed (дренажный или морозозащитный слой). It is done from (гравия, шлака или грунта) treated with binders. 9. (Грунтовое основание) comprises thoroughly compacted upper layers of the roadbed. It receives all (нагрузки транспорта) and therefore is considered to be a very important element of pavement structure.
Translate from Russian into English.
1. Дорожная одежда является одним из важнейших и дорогостоящих элементов автомобильной дороги. Её стоимость составляет 50-60% от общей стоимости дороги.
2. Дорожная одежда – многослойная конструкция, состоящая из нескольких конструктивных слоёв, уложенных на тщательно спланированном и уплотнённом земляном полотне.
3. Дорожная одежда должна отвечать определённым требованиям. Она должна быть прочной, шероховатой и ровной, обеспечивающей высокий коэффициент сцепленияю.
4. Слои дорожной одежды проектируются с применением материалов различной прочности в соответствии с величиной действующих напряжений.
5. Местные материалы широко используются чтобы уменьшить стоимость строительства и сократить срок строительства.
Speaking
13. Comment on the pavement and its structural layers:
a). the surfacing c). the sub-base
b). the pavement base d). the subgrade
Writing
14. Write the summary to the text in English.
UNIT X. CONSTRUCTION
Pre-reading tasks
1. Translate the following words and memorize them:
| to blast removal alignment | seal to spread marking | settling to strip to stockpile |
2. Match the equivalents:
1. continuous right-of-way a) до некоторой степени
2. bearing ratio b) непрерывная (сплошная) полоса отвода
3. in-situ c) как только
4. motorized grader d) защитное покрытие
5. to some extent e) показатель плотности грунта
6. once f) напоминать выпуклость
7. to import g) начинать
8. commence h) световозвращающий отражатель
9. seal i) слегка выступать
10. retroreflector j) ограждение (установленное на раздел. полосе или на обочине)
11. to feature camber k) на месте
12. to protrude slightly l) вносить, вводить
13. crash barrier m) автогрейдер
Reading task
3. Read the text carefully and do the tasks that follow:
Road construction requires the creation of a continuous right-of-way, overcoming geographic obstacles and grades low enough to permit vehicle travel. Removal of earth and rock by digging or blasting, construction of embankments, bridges and tunnels, and removal of vegetation (this may involve deforestation) are often needed. A variety of road building equipment is employed in road building.
Once these activities are completed, construction of the pavement can begin.
Firstly the longitudinal and vertical alignment of the road is set out by a surveyor. The alignment of the road will be marked with control pegs. The pegs will have level markings as a control mechanism to ensure the road is constructed according to design levels.
Construction of the road commences with the stripping of the topsoil, within the road reserve. The topsoil is usually stockpiled nearby for the construction of embankments along the road. The in-situ ground will be removed, using a heavy motorised grader to a level specified by the civil engineer. This is considered as the roadbed level. It will be compacted using a heavy vibratory road roller. Once the roadbed has been compacted to the required density (as will be specified by the engineer), the pavement layers can now be imported.
The first layer to be imported is the selected subgrade. This is usually a gravel type material. Once placed the material is leveled off by a grader. It will be compacted to a required density, using a road roller.
The next layer to be imported is the sub-base. The subbase material is of a higher quality than the selected sub-grade. It is usually a gravel type
material with a high bearing ratio. While the material is worked Asphalt layer and roller
by a grader, it is mixed with water to aid compaction. Once the subbase layer has been compacted to its required density, the importation of the final layer can commence.
The final layer of a road is the base course consisting of gravel or crushed stone. The base course will be leveled of and compacted. Sometimes (usually for roads that will experience heavy loads) portland cement will be added to it, to ensure adequate strength of this layer. On top of the base course is placed a surface course which typically consists of asphalt concrete or a seal consisting of a mixture similar sized small stones, bitumen and portland cement. This surface course strengthens the pavement structure by spreading out the vehicle loads applied to the subgrade. It also provides a smooth and high-friction surface for vehicles to drive on.
Two important factors in road construction are ensuring adequate compaction of the pavement layers and ensuring quality control over the use of materials in the pavement layers.
Each layer should be compacted such that the density of the layer is relatively close the maximum dry density of that specific material. For road construction the density required is usually greater than 95% of the materials maximum dry density. This limits the possibility of the pavement layers from settling and therefore preventing any undulations and holes in the road surface.
Modern roads, and indeed many ancient ones, such as those built by the Romans, feature camber. This is designed to allow water to drain away from the road to its edges. Modern roads that carry motor traffic also employ camber in curves to aid traffic stability by allowing them to "bank into" the bend to some extent.
On the side of the road there may be retroreflectors on pegs, rocks or crash barriers, white toward the direction of the traffic on that side of the road, and red toward the other direction. In the road surface there may be cat's eyes: retroreflectors that protrude slightly, but which can be driven over without damage.
Road signs are often also made retroreflective. For greater visibility of road signs at daytime, sometimes fluorescence is applied to get very bright colors.
Comprehension check
4. Answer the following questions:
1. What does road construction require?
2. Who sets out the longitudinal & vertical alignment of the road?
3. What road building equipment is used during road construction?
4. What is the difference between the materials used in the subgrade & in the subbase?
5. What is the purpose of mixing the materials of the sub-base with water?
6. What does the final layer consist of?
7. Asphalt concrete or a seal is used in a surface course, isn’t it?
8. Can you name the important factors in road construction?
9. What does the low density of each layer lead to?
10. What is camber designed for?
11. Are there any special devices on the side of the road? What is their purpose?
12. What is added to road signs to make them brighter at daytime?
5. Decide whether these statements are true or false:
1. Removal of earth and rock by digging or blasting, building embankments, bridges and tunnels are often needed when the road is constructed.
2. The longitudinal and vertical alignment of the road is set out by road planners.
3. The removed topsoil is usually stockpiled nearby for rehabilitation of newly constructed embankments along the road.
4. A heavy motorized grader is used to remove the in-situ ground.
5. The first pavement layer to be imported is the selected sub-base.
6. The sub-based material is usually a gravel type material which is worked by a grader and mixed with water to aid compaction.
7. The base course is the final layer of a road.
8. The density of each layer shouldn’t be close the maximum dry density of the specific material to prevent any undulations and holes in the road surface.
9. Modern roads feature camber.
10. Road signs are not retroreflective.
Vocabulary practice
6. Choose the right translation of the word:
1. уклон a) level b) shoulder c) grade
2. взрывать a) to blast b) to penetrate c) to compact
3. удаление a) development b) removal c) reduction
4. колышек a) mark b) peg c) barrier
5. складировать a) to keep b) to remove c) to stockpile
6. плотность a) density b) location c) quality
7. грунтовое основание a) subsoil b) pavement base c) subgrade
8. слой износа a) surface course b) wearing course c) base course
9. распространение a) digging b) blasting c) spreading
10. оседание a) overcoming b) settling c) alignment
7. Match the words with their definitions:
1. right-of-way a) is a mixture of bitumen and stone
2. asphalt b) movements of people and vehicles along roads and streets
3. pavement c) is a mixture of cement and stone
4. traffic d ) central part of the road used by wheeled traffic
5. subbase e) the land needed for road pavement, shoulders, ditches, side slopes
6. carriageway f) is a rigid or semi-rigid upper layer of the surface of the road
7. concrete g) is a thoroughly compacted upper layer of the roadbed
8. gravel h) a self-propelled wheeled machine with a steel blade used to level roads, hills and cuts
9. road i) to put flat stones, bricks, etc. on a path, a road, etc.
10. motor grader j) specially prepared way between places for the use of pedestrians, riders, vehicles
11. to pave k) small stones with coarse sand
12. subgrade l) is a layer resistant to moisture, which is made of gravel, slag, soil treated with binders
8. Choose the right verb:
1. When constructing a road builders should carry away | exclude | overcome| overtake different obstacles.
2. Builders sometimes compact | add | place | level Portland cement to the base course to ensure adequate strength of this layer.
3. The surface course spreads out the vehicle loads and at the same time strengthens | involves | cuts | compacts the pavement structure.
4. A borrow pit (source for obtaining fill, gravel, and rock) and a water source should be divided | located | used | indicated near or in reasonable distance to the road construction site.
5. Old road surfaces, fences, and buildings may need to be blasted | removed | allocated | erased before construction can begin.
Language Focus
9. Match the words with their synonyms:
a) to commence, to employ, to strip, to permit, to introduce, to aid, to select, bend, to specify.
b) to remove, to import, turn, to choose, to begin, to determine, to apply, to help, to allow.
10. Arrange the words according to the parts of speech:
| Noun | Verb | Adjective |
Variety, creative, import, selection, remove, select, creation, vary, importation, survey, selective, continue, create, removable, continuous, surveyor, various, strengthen, removal, strength, spread, reflect.
Speak on:
11. Speak about road construction stages, using the following clichés:
First, the author discusses … .
Attention is drawn to the fact that … .
Further it should be noted that … .
A detailed description of … is given.
The author emphasizes the fact that … .
The final part of the article reports on … .
UNIT XI. MAINTENANCE
Pre-reading tasks
1. Translate the following words and memorize them:
| pothole trash to deteriorate to patch to schedule | edge snow fence snowdrift snowplow sealing |
2. Match the English words with their Russian equivalents:
1. traffic facilities a) бульдозер с прямым отвалом
2. drain clearing b) ремонт выбоин (ямочный)
3. emergency maintenance c) разрушенные участки
4. pothole patching d) по крайней мере
5. to scatter salt e) накапливать
6. major failure f) очистка дренажных канав
7. routine maintenance g) серьёзное разрушение
8. worn spots h) разбрасывать соль
9. straight-blade dozer i) текущий ремонт
10. at least j) транспортные сооружения
11. to pile up k) срочный текущий ремонт
Reading task
3. Read the text carefully and do the tasks that follow:
The life of a road structure depends on the quality of its maintenance and minor renovation. Maintenance keeps the roadway safe, provides good driving conditions, and prolongs the life of the pavement, thus reducing the road investment. Maintenance consists of activities concerned with the condition of the pavement, shoulders, drainage, traffic facilities, and right-of-way. It includes the prompt sealing of cracks and filling of potholes to prevent water entering through the surface, the removal of trash thrown on the wayside by the traveling public, and the care of pavement markings, signs, and signals. In rigorous winter climates, substantial effort is required to remove snow and ice from the pavement, to scatter salt for snow and ice removal, and to spread sand for better traction.
In many countries an increasing share of road budgets is being allocated to rehabilitation and maintenance of existing roads, rather than new road construction.
Routine maintenance refers to activities such as grading, grass cutting, drain clearing, pothole patching, and shoulder repairs, which are performed at least yearly if not more frequently. Periodic maintenance activities are typically scheduled over periods of several years and include resurfacing and bridge repairs. Rehabilitation involves more substantial intervention to strengthen a road, repair structural defects, and restore the road to its initial condition, often after it has deteriorated to an "unmaintainable" standard. Rehabilitation sometimes also includes changes or improvements to previous characteristics, for instance, by widening, making small alignment changes, or providing footpaths.
Other maintenance activities include seasonal maintenance, such as snow clearing and flood repairs, emergency maintenance to restore roads after major failures, and the regular maintenance of road signs.
Repairing damage and resurfacing. Gravel and other similar type roads have to be smoothed quite often. Surfaces and edges of bituminous materials are repaired by patching with new material where worn spots develop from travel or because of weak spots in the ground underneath. Every 10 or 15 years many roads with bituminous surfaces are resurfaced completely.
Workers repair concrete pavements by digging out broken sections and putting in new concrete. They often repair cracks by filling them with asphalt. Many older concrete pavements must be resurfaced completely.
Deteriorated pavements can be reconstructed in several ways:
- the surface can be treated to improve its characteristics;
- the existing course can be overlaid;
- the damaged layers can be removed and replaced;
- the existing wearing course can be remixed with additional materials.
Clearing ice and snow. Most roads and highways must serve the year around. So they must be kept free from snow and ice in winter. In some places, snow fences are put up. These are thin pickets wired together and placed parallel to the road, on the side from which the storm winds usually blow, and about 50 to 100 feet (15 to 30 meters) from the road. Snowdrifts then do not pile up on the road.
V-shaped or straight-blade dozers clear the roads when it snows. In deep drifts, special snowplows are needed.
Often roads and highways that are slippery from ice and snow must have salt, chemicals, sand, or cinder spread on them to keep them passable.
Comprehension check
4. Answer the following questions:
1. What does the life of the road structure depend on?
2. What does maintenance include?
3. It is better to maintain and rehabilitate existing roads than construct new ones, isn’t it?
4. What types of maintenance are there?
5. What are the ways of reconstruction of deteriorated pavements?
6. What means of protection from snow do you know?
7. What kinds of machines are used to protect roads from snowdrifts?
8. Do most of roads and highways meet the requirements of modern traffic?
Vocabulary practice
5. Choose the right translation of the word:
1. to prevent a) насыщать b) предотвращать с) сохранять
2. binder a) покрытие b) маршрут с) вяжущее вещество
3. to spread а) улучшать b) распределять с) обрабатывать
4. to reduce a) регулировать b) уменьшать с) насыпать
5. to penetrate a) проникать b) размещать с) противостоять
6. alignment a) конструкция b) трасса с) устойчивость
7. to deteriorate a) удалять b) ухудшать с) улучшать
6. Match the words in A with an appropriate ending in B:
| A | involves | B |
| 1.Routing maintenance 2.Periodic maintenance 3. Rehabilitation 4.Seasonal maintenance 5.Emergency maintenance | a) resurfacing and bridge repairs scheduled over periods of several years. b) restoration of the road to its initial condition and sometimes widening, making small alignment changes or providing footpaths. c) grading, grass cutting, drain clearing, pothole and shoulder repairs which are carried frequently. d) restoring roads after major failures and repairing of road signs. e) snow clearing and flood repairs. |
7. Fill in the blanks using the words below and translate the sentences:
to suit, slippery, to clear, conditions, caused, bends
Driving in bad weather _______ creates extra difficulties. An early indication of likely weather conditions allows motorists to change their driving _______ those conditions. Statistics also show that such early warnings (предупреждения) have saved lives, particularly at dangerous ______. For example, in Finland where most travel is by road, and where one in four accidents are ______ by speeding on icy roads warning of coming snow or ice is essential. This allows road workers _______snow and prevent ________ surfaces, thus preventing many accidents.
Language focus
8. Read and translate the following words paying attention to the prefix “re-”:
resurface, reconstruct, restore, replace, remove, remix.
9. Form nouns from the following verbs and translate them:
to care - . . .; to improve - . . .; to repair - . . .;
to treat - . . .; to wire - . . .; to deteriorate - . . .;
to attach - . . .; to align - . . .; to strengthen - . . .;
to protect - . . , to remove - . . , to smooth - . . . ..
10. Match the words with their synonyms:
a) to continue, shoulder, to spread, to plan, to connect, damage, traction.
b) failure, wayside, to prolong, adhesion, to schedule, to scatter, to wire.
11. Match the words with their antonyms:
a) to improve, to destroy, to narrow, restoration, final, under.
b) initial, to rehabilitate, failure, above, to widen, to deteriorate.
Speaking
12. Speak on:
1. The significance of maintenance for the life of a road.
2. The main types of maintenance activities.
3. Ways of repairing damage and resurfacing.
4. Maintenance activities in winter.
UNIT XII. ROAD JUNCTIONS AND INTERSECTIONS
Pre-reading tasks 1
1. Translate the following words and memorize them:
| junction intersection | collision pedestrian | flyover to weave |
2. Match the equivalents:
1. overpass a) затор (в движении транспорта)
2. to drop speed b) сквозной проезд
3. underpass c) пересечение в форме клеверного листа
4. segregation d) площадь кругового движения
5. safeguards e) снижать скорость
6. clover-leaf junction f) сближение, схождение в одной точке
7. roundabout g) путепровод под дорогой, подземный переход
8. convergence h) разделение потоков движения
9. congestion i) путепровод над дорогой; эстакада
10. through route j) меры безопасности
Reading task 1
3. Read the text carefully and do the tasks that follow:
A road junction, as the term is generally used, is the point at which one road meets another; an intersection is the point at which two or more roads cross each other. Both junctions and intersections are, of course, the worst danger spots in a road system.
The problems of reducing danger at these points are those of cost and space. If junctions and intersections are such that all classes of traffic meet each other at the same level, there is a danger of collision, not only between cars of the same class but between those of different classes. Almost complete segregation of different classes can be achieved, and the need for users of the same class to cross traffic streams, the most dangerous process of all, can be avoided.
The perfect example of complete segregation of different classes of traffic and of the avoidance of crossing traffic streams is the clover-leaf junction, at which no collision can occur between vehicles if the drivers of those leaving the junction can manage to avoid those already on the road which they are approaching - which is a difficult thing.
All forms of road junction can be classified into three groups: multi-level junctions, roundabouts and flyover-junctions.
a) Multi-level junctions. The clover-leaf, the most typical of these, has already been mentioned. There is need for multilevel intersections where three conditions are fulfilled:
1. only a small percentage of the traffic must turn to left or right, and;
2. the major volume of traffic is travelling on a fast through route;
3. the volume of traffic would otherwise be sufficient to justify the provision of a roundabout.
b) Roundabouts. Unlike multi-level intersections, roundabouts do not enable traffic to cross without dropping speed but pedestrians and cyclists cannot be segregated unless costly over- or under-passes are constructed.
The success of a roundabout depends greatly upon the ease with which vehicles using it can "weave" or pass from one traffic lane to another. The greater the length of the road in which the weaving can be carried out and the smaller the angle of approach of converging streams of traffic, the more easily can weaving be performed. The angle should not be greater than 30 degrees. The greater the diameter of the island, the smaller the angle of convergence.
c) Flyover-junctions. These have been developed chiefly at places where there are no pedestrians (and cyclists are few, if any). These "flyovers", which enable high speeds to be maintained, are extremely expensive, costing about ten times as much as a roundabout, so it is much better to have ten roundabouts at ten dangerous junctions than a single flyover at a single junction.
Comprehension check
4. Answer the following questions:
1. What are the most dangerous spots in a road system?
2. What problems are connected with the problems of reducing danger of these points?
3. How can complete segregation of different classes of traffic be achieved?
4. What types of road junctions do you know?
5. What does the success of a junction depend on?
6. What can you say about the angle of approach of converging streams of traffic?
7. Where have flyover-junctions been developed?
5. Choose the best variant to complete the sentences:
1. There is a danger of collision between vehicles of the same class and those of different classes if...
a) ...there is no need for drivers to cross traffic streams;
b) ...there is a clover-leaf junction;
c) ...all classes of traffic meet at the same level at intersections.
2. Multi-level intersections are adopted when...
a) ...only a small percentage of traffic travels on a through road;
b) ...the traffic must cross the street necessarily dropping speed;
c) ...the major volume of traffic is travelling on a fast through route without dropping speed when passing the junctions.
3. A roundabout is considered successful if...
a) ...the angle of approach of converging streams of traffic is very large; b) ...the vehicles using it can easily reach different exits as directly as possible passing smoothly from one traffic lane to another at a small angle of convergence;
c) ...the road for the vehicles to pass from one traffic lane to another is too short.
4. Flyover junctions are not very widely used as...
a) ...they do not enable high speeds to be maintained;
b) ...they cost ten times as much as a roundabout and are designed for roads where pedestrians and cyclists are excluded;
c) ...they are manageable only on roads which accommodate pedestrians and pedal cyclists.
Vocabulary practice
6. Choose the right translation of the word in bold:
1.perfectexample a) совершенный b) идеальный c) законченный
2. to pass from one lane to another a) передавать b)проезжать c) обгонять; двигаться; переходить
3. to maintain high speeds a) обслуживать b)ремонтировать c) сохранять
4. ten times as much as a roundabout a) время, раз b) сколько c) так же много, как, столько же, больше
5. to be of great value a) математическая величина b) ценность, значение c) стоимость
Follow up activity
7. Read the text in 2 minutes and answer the question:
How can the problem of safety be solved?
Roads appeared in the far-off times and were first in the form of pedestrian tracks. Then, as civilization progressed, they became routes along which horse-drawn traffic and finally vehicles moved.
Roads have always had a dual function: as traffic routes and as a means of approach to dwellings and other buildings. But since the growth of transport these functions have been seriously in conflict with each other. Today this conflict is extremely great and leads to great danger.
Any town so planned that its citizens are killed in great numbers is an ill-planned town. The layout of all newly developed areas must be made dependent on the safety factor. Pedestrians and fast motor traffic will never and can never mix - they must be isolated.
Pre-reading task 2
8. Match the equivalents:
1. pedestrian subway a) одностороннее движение
2. urban b) переулок
3. flow c) обочина; бордюрный камень
4. directional control d) двустороннее движение
5. peak hours e) контроль за направлением движения
6. signposting f) гужевой транспорт
7. carrying capacity g) встречный поток движения
8. one-way traffic h) часы пик
9. opposing traffic i) городской
10. kerb k) система знаков и указателей
11. side street l) пропускная способность дороги
12. two-way traffic m) пешеходный тоннель
13. horse-drawn vehicles n) поток
Reading task 2
9. Read the text carefully and do the tasks that follow:
Traffic Control
1) It is obvious that in existing urban areas much of the congestion is due to narrow streets and junctions which are incapable of taking peak-hour traffic. The solutions to this problem are costly. They include adequate roundabouts and street widening, and the segregation of traffic by means of flyover roads, underpasses, bridges, and pedestrian subways.
(2) Much of the congestion in urban areas is due to traffic which has no business in the area but is only passing through. There is a tendency for drivers to keep to the well-lit shopping streets. If they can be made to use less important streets and those not occupied by shops, then conditions are improved not only for the through traffic but also for the local traffic.
(3) Signposting is, of course, a directional control and a very effective one. In fact it is important for all signs and symbols used on the roads to be seen, well in advance, by drivers approaching at normal speed. Directional control cannot increase the capacity of the highway system but it can avoid local congestion.
(4) One-way traffic is a special kind of directional control which is very effective in maintaining the traffic flow in congested areas.
(5) A major cause of congestion in towns is the interruption to the free flow of traffic by cross traffic at junctions. But if the need for traffic streams to cross each other can be avoided then the movement of vehicles will be much easier. This easier movement of traffic can often be achieved by making traffic move in one direction only along certain streets and by prohibiting incoming vehicles from side streets from crossing the main stream. The streets may be either one-way or two-way according to local conditions of traffic or width of carriageway, and traffic at the junctions can be guided by constructing suitably-shaped islands. Besides one-way traffic can also be introduced where the carriageway width is inadequate for two opposing lines of traffic.
(6) The disadvantages of a one-way traffic system are that it increases the distance travelled by some vehicles, that it makes it more difficult for strangers to find their way about. The true aim of a one-way system is to eliminate cross traffic, and under conditions of continuous flow on crossing streets the introduction of a properly designed one-way scheme can double the carrying capacity of the highways.
(7) The two main objections to street intersections are that they are a cause of accidents and that they interrupt the flow of traffic. The best thing to do with intersections is to get rid of them. If that is not possible they may be improved and made safer but they will always remain a source of danger and delay.
(8) Many accidents are caused because traffic streams of different types, or traffic streams travelling in different directions, are using the same carriageway, and these accidents can be avoided either by reservations between traffic lanes, or by vertical (or "grade") separation.
(9) In many cities in America and in Europe segregation of traffic is achieved by means of flyovers or underpasses; at some junctions there are even three different levels. Each has its advantages and disadvantages according to the circumstances. Flyover structures are not always 1.9 km long Flyover at Khilgaon Rail & aesthetically pleasing while Road Intersection in Dhaka City, Bangladesh
an underpass may be more expensive to construct. The separation of fast and slow traffic from the heavier and faster traffic is most desirable not only in the interests of freedom of traffic movement, but also of safety. This ideal is not easy to achieve.
(10) Urban traffic control will be of benefit to the general public in the district concerned and will result in greater comfort for road users of all classes, as well as bringing economic advantages to the community as a whole.
Comprehension check
10. Group the following sentences according to the topics:
A. The problems created by motor traffic growth.
B. Ways of solving the traffic congestion problem.
C. Advantages of a one-way traffic scheme.
1. A great intensity of traffic makes it necessary to lower the average speed of vehicles. 2. The problem of avoiding traffic congestion is one of the most important. 3. Under conditions of continuous flow on intersecting streets a properly designed one-way scheme can double the carrying capacity of the highways. 4. The extraordinary growth of motor traffic has created traffic difficulties demanding new designs and planning. 5. Roundabouts, streetwidening and the segregation of traffic by means of flyover roads, pedestrian subways, underpasses are possible solutions of the congestion problem though they are costly and demand space. 6. A special kind of directional control—one-way traffic—obviates the necessity for traffic streams to cut across each other. 7. Narrow streets and junctions are incapable of taking peak-hour traffic. 8. Directing the traffic stream to less important streets may improve both the through and local traffic. 9. With the carriageway width inadequate for two opposing lines of traffic a one-way scheme is advantageous though it increases the distance travelled by vehicles.
11. Match the sentences with the paragraphs of the text. Put them in order according to the text:
1. The importance of signs in the control of direction choice.
2. The advantage of having one-way streets.
3. Segregation of different types of traffic is an ideal not easy to achieve.
4. The necessity of introducing grade separation.
5. The roads where congestion in town takes place.
6. The danger of having street intersections.
7. Drivers themselves may bring about congestion.
8. The disadvantages of one-way traffic.
Speaking
12. Speak about traffic control using the following clichés:
This text deals with …
The author pays great attention to the …
Advantages and disadvantages of the … are discussed.