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10.03.2022 08:02

Английский язык

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On laying out a new road certain general principles have to be kept in mind. motive power is economized by easy gradients; at the same time it is not desirable to deviate much from the direct route between the fixed points (towns and villages) through which the road must pass since excavation works are expensive; these must be as small as possible. a careful survey of two or three trial lines should be made before the route is finally decided upon; this involves also an examination of the geological features of the district and of streams which have to be crossed by bridges. in fact, the formation of an extended line of road involves the construction of bridges, viaducts and other important works which require the greatest engineering skill. it is important to be well acquainted with the nature of the country which is to be traversed whether flat or hill. it is equally important to consider the weather conditions. to make tunnels, cuttings, embankments, foundations for bridges, constructing canals or roads it is most necessary to know the character of the rock met with, especially whether hard or soft and whether permeable or not to water. one must also know what rocks are obtainable and suitable for roads metal. every kind of road serves its own purpose. according to their technical characteristics roads can be classified as follows: primitive roads. these are natural roads where no road construction work has been made. to these belong the natural rural roads and tracks. only the lowest speeds are possible here as a rule. such roads are only passable for a part of the year. seasonal roads are roads having a specially constructed carriageway, proper drainage must be made. in favourable seasons great speeds are possible here. these roads are not passable in certain parts of the year. there exist seasonal cart-roads, tractor roads and motor roads. permanent roads of local transport. these roads have a specially constructed stable carriage-way, adequate drainage facilities and adequate road surfacing securing traffic all the year round. with proper maintenance high speeds are possible on these roads. permanent motor car roads or motorways, having a specially constructed stable carriageway with a road surface of an improved type. these roads are constructed for high-speed traffic. all superhighways of first class roads are roads of this kind. they usually cover long distance and are constructed according to strict technical regulations. these roads are constantly being improved so as to meet all the requirements of comfortable driving. they are equipped with special maintenance facilities, repair shops, gasoline stations, etc. such a highway for example has been laid from moscow to the crimea. there is a filling station at every hundred kilometers and a hotel at every three hundred kilometers. people from different central cities are able to travel to the black sea in buses or cars of their own. every kind of road we are building has a definite purpose in view, all of them working for the great purpose of the people’s welfare according to the plans of economy development.