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Поставьте глаголы в скобках в нужную форму.
1. The highway engineering faculty (to train) the students in several qualifications. 2. The road structure (to consist) of the subgrade, subbase, drainage layer and pavement. 3. For building the road various building materials (to use). 4. The road pavement (to make) usually of asphalt-concrete or cement-concrete. 5. Various artificial structures also (to belong) to the road construction. 6. The curriculum of the faculty (to induce) a lot of specialized subjects. 7. The most part of transportation (to employ) by means of roads. 8. The highway development policy (to induce) the construction, maintenance and operation. 9. The designing of roads also (to study) at the faculty. 10. The economic analysis (to be) the most important factor in road construction. 11. The highway economy (to include) two main elements. 12. The sum of two cost elements (to constitute) the highway transportation cost. 13. The motor vehicles (to influence) the roadway condition. 14. The damage of the pavement (to cause) by the motor vehicle loads. 15. The traffic safety (to provide) by many factors of road maintenance.
8. Ответьте на вопросы.
1. What qualifications are trained at the faculty?
2. What are the main elements of the road?
3. What artificial structures belong to the road?
4. What specialized subjects do the students of the faculty study?
5. What is the main purpose of highways?
6. Why is knowing the properties of road-building materials important?
7. What is the corner-stone of highway design?
8. What economical factors are essential in road-building?
9. What is the highway transportation cost?
10. What causes the damage of the pavement?
11. What does repair of the road involve?
12. What is the final aim of the proper highway maintenance?
9. Прочитайте и переведите отрывки, дополняющие информацию из текста. Ответьте на вопросы.
What aspects of highway policy should each engineer take into account? What can the applied loads cause? What is the maintenance of the road? What factors should be avoided during road designing?
1. Each highway engineer has unavoidable contact with three broad aspects of highway policies: development, operational and regulatory. The development policy deals with the construction, maintenance and operation of the highways. The operational policy concerns operation of the vehicles, because it greatly results in planning and design of the roads. The regulatory policy mainly concerns general regulation of transportation.
2.The roadway structure is the subject to the wheel loads of motor vehicles, which result in deflection of the surface and the underlying layers. The applied loads cause roughening and cracking of the pavement and in some cases can lead to the failure of road structure. In such cases the repair is needed. But it is much better to maintain the road properly.
3. Highway maintenance involves patching, filling ruts, removing surface corrugations, pouring cracks, blading surfaces, cleaning ditches and culvets, repairing bridges and fighting floods. It also includes operation of the highway as a safe, efficient and pleasing link in the nation’s highly important transportation system. This adds such duties as erecting signs and traffic control, painting traffic stripes, mowing grass and weeds, clearing away trash, removing snow, spreading cinders and other services which the public has come to expect.
4.The students of the faculty also study the designing of roads. The key-stone of modern highway design is to make the suitability of the highway for vehicle and driver as nearly perfect as possible. The designing of roads should be directed to eliminating accidents. The alignment should be the best obtainable when topography and urban development are considered. Sharp horizontal curvature should be avoided at the end of long tangents where surprise factor would cause many accidents. It is axiomatic that the longer the tangents, the flatter should be the connecting curve.
Прочитайте текст об истории развития дорожных сетей.
Mediterranean Sea – Средиземное море
Mayan – майя
Aztec – ацтеки
Incan – инки
Appia – город Апиа
Tresaguet – Трезeге (фамилия)
turnpike road – главная магистраль
Cumberland – Камберленд
ft -foot – фут
in- inch – дюйм
Traces of early roads have been found which antedate recorded history. The first hard surfaces appeared in Mesopotamia soon after discovery of the wheel about 3500 B.C. On the island of Crete in the Mediterranean Sea a stone-surfaced road constructed before 1500 B.C. was found. The direction in the Bible “make straight in the desert a high road“ refers to a road constructed soon after 539 B.C. between Babylon and Egypt. In the western Hemisphere evidence exists of extensive road systems constructed by the Mayan, Aztec, and Incan people of Central and South America. The Romans bound their empire together with an extensive system of roads radiating in many directions from Rome. The Appian Way, constructed southward about 312 B.C. illustrates the elaborate procedures that the Romans employed. First a trench was excavated to such a depth that the finished surface would be at ground level. The pavement was placed in three courses: a layer of small broken stones; a layer of small stones mixed with mortar and firmly tamped 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 followed 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.
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 extremely slow for a time after the Revolutionary War’s end in 1783. Poor roads 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 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 “Cumberland road” from Cumberland to wheeling was financed by the Federal government and was originally toll-free. It was authorized by Congress in 1806, and was completed 10 years later. It was 20ft in width, and 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 end of 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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