外文翻译--道路设计VIP免费

外文翻译 -- 道路设计附录 A 外文翻译原文Road Design History of Road Design Firstly let me apologise for this page. It is largely text based due to the nature of it and if reading is difficult then I am sorry. This is due solely to the material covered and is the only page in the series. This is not typical as the rest have graphics or images to keep you amused. Secondly this page is very much a history of road building in the United Kingdom( The first road builders of any significance in Western Europe were the Romans, who saw the ability to move quickly as essential for both military and civil reasons. It is from the Romans that the term highway comes as all their roads were elevated 1m above the local level of the land. This was to minimise the risk of an ambush, as was the best known characteristic of the roads, their lack of corners. The standards set by the Romans in terms of durability far exceeded anything achieved after the fall of the empire. The Roman approach to road design is essentially the same as that in current use. The roads were constructed of several different layers, increasing in strength from the bottom. The lowest layer was normally a rubble, intermediate layers were made of lime bound concrete and the upper layer was a flag or lime grouted stone slabs. The thickness of the layers was varied according to the local ground conditions. After the fall of the Roman Empire the road system fell into a state of disrepair and by the end of the middle ages, there was in effect no road system in the country. The only routes available were unpaved tracks, muddy and impassable in winter and dusty and impassable in summer. Diversions around particularly poor ...