CHAPTER SIX RAILWAY AND TRANSPORT6.1 Evolution of the Railway
6.1.1 Historical Outline a sketchy summary of the main points of an argument or theory
Since the dawn of human activity, the quick and safe transportation of people and goods has been a constant goal of every organized society. It is generally acknowledged, that the foundation innovations in the development of transportation included the discovery of the wheel, the railway and the airplane. Railway trains in their present form first made their appearance at the beginning of the 19th century in British mines. Their main characteristic is the guided movement of wheels by the track through metal-to-metal contact.
However, the forerunners of the railway appeared much earlier than the 19th century. Movement of carriages四轮马车 or wagons用运货马车运输货物 on metal guides is illustrated in a 1550 gravure（影印版a printing plate used in the process of gravure） found in Basel（巴塞尔a city in northwestern Switzerland）, Switzerland, which shows transportation methods employed in the mines of Alsace （a region of northeastern France famous for its wines）, The guided movement of carriages in general was already known in Roman times, as witnessed by grooves细槽，凹槽 carved雕刻 in the stone pavement to facilitate and speed up the movement of carriages.
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Railway and Other Competing Transportation Means Times has changed,
however, what was impressive in the early 20th century, was the reduced satisfaction with railways. Airplanes and private cars私家车；私人小汽车 have been offering transportation alternatives at every scale, which has given the pressure of competition, the railway had to modernize and improve, especially as regards speed ，reduction of
transportation costs and better organization and improvement of the services offered. Hence, we come to the era of high-speed trains (Fig. 6. I, Fig. 6. 2) operating at
250~~300km/h (a speed of 515km/h was attained by French Railway in 1990 in test runs), combined transport (combined rail-road transportation) and high- volume transport for both passengers (commuter service) and freight (bulk loads).
Fig. 6. 1 The Japanese Shinkansen high-speed Fig. 6. 2 The French TGV high-speed train
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Nevertheless, in parallel with the conventional railways (which are based on metal-to-metal contact), experimental development proceeded since the mid-1970s with techniques which, although using guided vehicle travel (like railways), avoid any contact between the moving vehicle and bearing sub-structure. These are the areotrain (Fig. 6. 3) and the magnetic levitation磁悬浮train, or maglev (Fig. 6. 4), which, in test runs试运转, has attained speeds of 422km/h for the areotrain in 1969 and 600km h for the maglev in 1991。 magnetic levitation high-speed rail technology; train is suspended on a magnetic cushion above
a magnetized track and so travels free of friction
6.2.1 The Application of High-speed in Railways
High-speed trains (with V>200km/h) represent railway making response to the transport market requirement for reduced travel times行程时间a period of time spent traveling. High speeds were pioneered by two railway networks:
The Japanese network, with the 1964 commissioning试车；试运转the act of granting authority to undertake certain functions of the \top speed of 210km/h.
1. The French Railway, by inauguration in 1981 the \巴黎至里昂间高速火车
（Train a Grande Vitesse）
high-speed train between Paris and Lyons, with a top speed of
260km/h, increasing to 270km/h in 1983 and to 300km/h in 1989.
Both lines were built on heavily traveled routes旅运路线 showing signs of saturation
饱和
. Faced with improving existing infrastructures
下部构造；基本建设
or
building a new high-speed line, the latter was chosen. High-speed lines were constructed in the 1980s in West Germany (Hannover-Wurzburg and Mannheim-Stuttgart), in Italy (Rome-Florence), in Spain (Madrid-Sevilla), in France ( \(through Channel Tunnel).
Two approaches to high speeds can be distinguished.
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In the first, only passenger（客运列车a train that carries passengers） trains run on high-speed lines, with low loads per axle, very small tolerance on track defects and large gradients（渐变，梯度 (up to 35%). This approach was implemented执行 in the Paris-Lyons line and presupposed预设的 the high passenger train traffic could make the construction and operation of the new line cost-efficient（有成本效益的；合算的productive relative to the cost）
In the second, the new high-speed lines are run by both passenger and freight trains, the coexistence (existing peacefully together) of which entails higher maintenance costs and retires lower values of longitudinal gradient纵向坡度. Most high-speed lines are currently designed for mixed traffic (both passenger and freight trains).
6.2.2Impact of High Speeds on the Reduction of Rail Travel Times :
The reduction of travel time was a constant goal of the railways, as can be seen from | Table 6.1. Only with high-speed trains, however, were the railway able to achieve 400— 700km routes, by which the travel times equal to or better than air travel Train travel time reduction on certain routes Table 6.1
Indeed,high-speed railways have the advantage to reach city centres and thus make travel times from the centre of a city to the centre of another far shorter tha for automobiles and even* in many cases, shorter than for airplanes (Table 6. 2)
Comparison of travel times from the centre of a city to the centre of another for high-speed trains, airplanes and automobiles Cease of the Paris-Lyons route) Table 6.2 TGV travel time access Automo TGV travel time AirplaneC 1) (on highway at a top time to railway station 1 h50min 2h30min 2h30min—3h 2. 3.
The time indicated is the sum of the flight time飞行时间；飞越时间, travel time
from the city centre to the airport and check in报到，记录 time.
The time indicated is the time from the centre of a city to the centre of
another, i.e. it takes into account the time necessary (about 30min) for a car to reach the highway from the city centre.
6. 3 Aerotrain and Maglev悬浮列车；高速铁道
磁力悬浮火车
6.3.1 The Aerotrain
The technologies of areotrain and magnetic levitation磁悬浮train are based on guided vehicle transport (like conventional trains), but avoid any contact of the moving vehicle with the bearing structure on which transport is taking place, whereas railways rely on the metal (wheel) to metal (track) contact.
The areotrain ( Fig. 6. 3 ) is a vehicle running on a concrete bearing substructure in with shape of an inverted being in such a position that top and bottom are reversed \
Propulsion推进；推进力is achieved without any wheel system, by a compressed air cushion blown between the vehicle and the bearing substructure. The areotrain thus replaces the adhesion forces, necessary to conventional trains, by compressed air layer.
The technology was developed in the 1960s in France and in 1969 had achieved the impressive speed of 422km/h.
Even though there were various plans for areotrain construction (e.g. Paris- Orleans where 18km of bearing substructure had even built, Brussels-Luxembourg, etc. ), abandoned in the 1970s for various reasons. The main ones are: (1) The new technique is not compatible with conventional railways.
civil-engineering-(土木工程概论英文课件)CHAPTER-SIX-RAILWAY-AND-TRANSPORT
