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into place, and a wearing course of massive stone blocks, set and bedded in mortar. Many such roads are still in existence after almost 2000 years.

With the fall of the Roman Empire, road building became a lost art. It was not until the 18th century that Tresaguet (1716-1796) in France developed

improved construction methods that at a later time, under Napoleon, made possible a great system of French roads. Highway development in England Сfollowed soon after that in France. Mac. Adam (1756 - 1836) in particular

made use of crushed stone as a road-surfacing material in a manner that is still widely used with some modifications. Both in France and in England the problem was chiefly to produce a road surface usable under all conditions of weather.

иroads were the real cause of the Whisky Rebellion in western Pennsylvania in 1794 (the farmers of this area objected to a tax on the whisky that they were

Few roads were constructed during the history of the United States.

Most early settlements were located along bays or rivers, and transportation

was largely by water, on foot or horseback. Roads development was

“CumberlandбАroad” from Cumberland to wheeling was financed by the Federal government and was Дoriginally toll-free. It was authorized by Congress in 1806, and was completed 10 years later. It was 20ft in width, and

extremely slow for a time after the Revolutionary War’s end in 1783. Poor

making from grain). Construction of the Philadelphia-Candcaster Turnpike resulted from this incident. It was a toll road 62 miles long, surfaced to a width of 24ft with hand-broken stone and gravel.

Between 1795 and 1830 numerous other turnpikes, particularly in the

northeastern states, were built. For example, the “Old National Pike” or

consisted of a 12-in. bottom and a 6-in. top course of hand-broken stone. Some 20 more years elapsed before the road was completed to St. Louis.

The extension of turnpikes in the United States was abruptly halted by the development of the railroads. At the endИof the century, approximately 300 years after the first settlement, the United States could claim little distinction because of the character of its roads and turned to the countries of Europe for information of seeking knowledge on road-building methods. There were strong demands for rural road improvement although great improvements were made in city streets. After that the state highways continued to expand more than 2 decades.

Organization which coordinates the work concerning highways is called American Association of State Highway Officials (AASHO). It was established in 1914. Among other duties it prepares specifications, manuals, standards and publishes a quarterly magazine “American Highways”, which reports on current highway subjects.

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11. Complete the sentences from the text with omitted words.

1. ... of early roads have been found which antedate recorded history.

2. The Romans bound their empire together with an extensive system of roads radiating in many ... from Rome.

3. First a trench was excavated to such a ... that the finished surface would be at ground level.

4. Both in France and in England the problem was chiefly to produce a road

... usable under all conditions of weather.

5. The Philadelphia-Candcaster Turnpike was a ... road 62 miles long,

13. Complete the table using information from the text «Early roads» (ex. 10).

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14. Read the text on highway economy and answer the questions.

What is the role of roads in society? What economical benefit can they bring?

What aspects constitute highway construction cost?

СHighways are constructed because they provide benefits to society as a

whole or as individuals. Good transportation facilities raise the level of the entire economy by providing for ready transportation of goods; they are of assistance in problems of national defense; they make easier the provision of community services like police and fire protection, medical care, schooling, and delivery of the mails; they open added opportunities for recreation and travel.

иHighways benefit the landowner because ready access makes his property more valuable. They benefit the motor-vehicle user through reduced cost of

money invested.бА

vehicle operation, savings in time, reduction in accidents, and increased comfort and ease of driving. On the other hand, road improvements take money that might be used for other productive purposes by individuals or by government. They can be justified only if the benefits exceed the costs entailed in providing them, including some allowance for return on the

The total cost of motor transportationДis the essential consideration in long-term planning for highways. For many years attention was focused

largely on the relative economy of various types of road surfacing, and later on the costs of motor-vehicle operation. The direction in highway economics includes the following: cost of motor-vehicle operation; cost of motor-fuel consumed, oil consumption, tire costs, vehicleИrepair and maintenance, depreciation, stopping and starting an automobile costs, accidents costs.

15. Give a talk on your speciality (highway engineering, highway economy).

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II.BRIDGE ENGINEERING

1.Read the words and study them by heart.

Bridge, general, grade, alignment, highway, engineer, aiming, design, rigid, carrying, stage, right, angle, large, opening, building, rigid, loading, along, longer, weight, straight, stringer, slightly, length, greatly, advantage, wing.

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BRIDGE ENGINEERING

иsuperstructures carrying the roadway between these supports. Types of bridges include slab, truss, arch, and suspension bridges, each with a

Bridge engineering is one of the oldest specialities of our academy. Highway bridge engineers use the same analytical tools as other structural

engineers. Principal differences are in clearance and loading requirements.

alignment.бАSometimes there may be sharp turns at the approaches because the most favourable bridge site was theДsole criterion for the location. Today the general policy is to determine the proper highway location and require the

Bridges consist of substructures of abutments and piers under

distinctive form of superstructure. Rigid frames are bridges in which the substructure and superstructure are rigidly joined. A further distinction is made in terms of materials, the most common of which are reinforced concrete, steel, and timber.

The important construction for the bridge structure is the approach

bridge engineer to furnish structures for it. This of course results in more expensive crossings, for skew bridges cost more than rightangle ones, and the

introduction of horizontal and vertical curvature into large bridges creates serious design and construction problems. However,Иthe end result is a better

roadway. When the approximate location is fixed, there must be a complete and extensive report and special survey for the site. It should include accurate data on the channel or waterway for all stages of water, the foundation conditions, and the stream character.

The form and proportion of the structures are varied considerably in different situations and are matters for cooperative determination. Arch and rigid-frame-type bridges with stone masonry walls have been commonly accepted on many parkways as appropriate for the short span over a highway and over small streams. The concrete iron bridge has also been popular along parkways, because of its lower costs. Today there is a tendency for highway bridgework to be a beam-type open-deck structure, supported by columns and with little emphasis on abutments.

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