Rail transport refers to the land transport of passengers
and goods along railways or railroads. A railway (or railroad) track consists
of two parallel rail tracks, formerly of iron now of steel, generally
mounted upon cross beams (termed "railroad ties" (US) or "sleepers"
(UK) ) of timber, concrete or steel. The underlying support maintains
the rails at a fixed distance (gauge) apart. Usually vehicles running
on the rails are arranged in a train (a series of individual powered or
unpowered vehicles linked together). The cars move with much less friction
and the locomotive that pulls the train uses much less energy than is
needed to pull wagons. In the 20th century longer and longer trains were
devised so that labor costs are minimized.
General
Rail transport is an energy efficient means of mechanised land transport.
The rail tracks provide very smooth and hard surfaces on which the wheels
of the train may roll with a minimum of friction. As an example, a typical
rail car can hold up to 125 tons of freight with this and the weight of
the car on two four-wheel bogies. Fully loaded, the contact between each
wheel and the rail is the space of about one U.S. ten-cent piece. This
can save energy compared with other forms of transportation, such as road
transport which depends on rubber wheels on pavement. Trains also have
a small frontal area in relation to the load they are carrying, which
cuts down on air resistance and thus energy usage. In all, under the right
circumstances, a train needs 50-70% less energy to transport a given tonnage
of freight (or given number of passengers), than does road transport.
Furthermore, the rails and sleepers distribute the weight of the train
evenly, allowing significantly greater loads per axle/wheel than in road
transport, leading to less wear and tear on the right of wail transport
makes highly efficient use of space: a double-tracked rail line can carry
more passengers or freight in a given amount of time than a four-laned
road.
As a result, rail transport is often the major form of public transport
in many countries. In Asia, for example, many milliomercially, rail transport
has had a mixed record. Most rail systems, including urban metro/subway
systems, are highly subsidised and have never or rarely been profitable;
however, their indirect benefits are often great. For example, despite
a well-developed network consisting of four grades of trains and a widespread
urban rail network in Seoul and Pusan, Korean National Rail is a nationalized
organization that has never come close to having receipts equal costs.
Further information: Transportation in South Korea
Similarly, passenger rail in all countries is dependent on government
subsidies. As a result levels of rail transport have in some times and
places been reduced in order to save money.Further information: Beeching
Axe
Conversely, US freight railways have consolidated and become more efficient
in their progress toward profitability. The East Japan Railway Company
has taken an innovative and creative marketing stance and have achieved
profitability as a resirements for security in the face of recent terrorism
incidents, for instance the Madrid train bombings of 11 March 2004. Securing
railways is often more difficult than other modes of transport because
stations are designed with easy access and high capacity as their primary
goals rather than security; because most trains make many stops, rendering
any sort of passenger screening difficult; and because securing the tracks
as they run through cities and the countryside is impractical.
Operations
A rail transport system consists of several necessary elements, and should
be viewed from a system-wide perspective when planning, constructing and
maintaining it. Some locomotives may be wonderfully aesthetic constructions,
but they will not work unless they are given an appropriate system on
which to run. This system includes infrastructure such as tracks, railroad
switches or points,nto which the permanent way is built. Next are the
requirements of the system – what was it built for? For carrying
cargo, commuters, medium or long-distance travellers? Has that requirement
changed over time and left the system to adape of system? Is it light
rail or rapid transit, high-speed or industrial rail? To what gauge is
it built? In a broader sense, rail transport includes monorail, rubber-tyred
metros and maglev, since the cars also run in a guided path. (The term
"guideway" describes the non-traditional modes better.)
Trains require a propulsion mechanism: horses, or steam, diesel or electric
locomotives. The last of these options, the most energy-efficient, requires
electrification of the system. To be electrified, a means of supplying
electricity to the train is needed. This can be done witha single track
used by trains in both directions; on rail lines like these, "crossovers",
"passing loops" or "passing sidings", which consist
of short stretches of double track, are provided along the line to allow
trains to pass each other, and travel in opposite directions. Alternatively,
there may be longer sections of the line that are double track - effective
timetabling can allow train travel up and down a partially double-track
line equivalent to travel on full double tracks. Conversely, double tram
track is sometimes interlaced at narrow passages (see tram tracks). Single-track
lines are cheaper to build, but can handle only a limited amount of traffic
and are consequently mainly used on branch lined freight in the 1960s,
rail and ship transportation have become an integrated network that moves
bulk goods very efficiently with a very low labor cost. An example is
that goods from east Asia that are bound for Europe will often be shipped
across the Pacific and transferred to trains to cross North America and
be transferred back to a ship for the Atlantic crossing.Major cities often
have metro and/or light rail/tram systems. For a tram on the road the
terms streetcar track, tram track or tramway are used, rather than railway
or railroad.LevelUsually railways are at ground level. However, in hilly
terrain and mountains, to avoid large slopes, the railway is at some places
elevated, on an embankment or bridge / viaduct, and at some places in
a cutting (ditch / trench) or tunnel. The same are also used for non-level
crossings. In the case of many crossings, such as in a city, a longer
stretch may be elevated or underground.
Safety and railway disasters
Train wreck, 1907, in Canaan, New HampshireTrains can travel at very high
speed, are heavy, are unable to deviate from the track and require a great
distance to stop. Possibilities for accidents include jumping the track
(derailment), head-on collision with another train coming the opposite
way and collision with an automobile at a level crossing (also called
a grade crossing). Level crossing collisions are relatively common in
the United States where there are several thousand each year killing about
500 people - although the comparable figures in Britain are 30 and 12.
For information regarding major accidents, see List of rail accidents.The
most important safety measure is railway signalling. Train whistles warn
others of the presence of a train, trackside signals maintain the distances
between trains. In Britain, vandalism is thought responsible for about
half of rail accidents.Railroad lines are zoned or divided into blocks
guarded by combinations of block signals, operating rules, and automatic-control
devices so that at most one train may be in a block at any time . Such
traffic control is done in a similar way to air traffic control.
Compared to road travel, railways remain relatively safe. Annual death
rates on roads are over 40,000 in the United States & about 3000 in
Britain, compared with a thousand passenger fatalities on railways in
the United States and under 20 in Britain. (Sources: U.S. Department of
Transportation and U.K. Health & Safety Executive).
History
Main articles: History of rail transport, and Heritage railway, and [[]],
and [[]], and [[]]
The Diolkos was a 6-km long railway that transported boats across the
Corinth isthmus in Greece in the 6th century BC. Trucks pushed by slaves
ran in grooves in a limestone track. The Diolkos ran for over 1300 years,
until 900 AD.
The first horse-drawn wagonways appeared in Greece, Malta, and parts
of the Roman Empire at least 2000 years ago, using cut-stone track. They
began reappearing in Europe from around 1550, usually operating with crude
wooden track.
In the late 18th century iron rails began to appear: British civil engineer
William Jessop designed edge rails to be used with flanged wheels for
use on a scheme in Loughborough, Leicestershire in 1789 and subsequently
opened an iron-works to produce more rails. In 1802, Jessop opened the
Surrey Iron Railway in south London - arguably the world's first public
railway, albeit a horse-drawn one.The first steam locomotive to operate
on rails, built by Richard Trevithick, was operated in 1804 in Wales.
It was not financially successful, with Trevithick ending bankrupt. In
1806 a horse-drawn railway was built between Swansea and Mumbles. In 1807
this railway started carrying fare-paying passengers - the first in the
world to do so.In 1811 John Blenkinsop designed the first successful and
practical railway locomotive[1].He patented (No 3431), a system of moving
coals by a rack railway worked by a steam locomotive, and a line was built
connecting the Middleton Colliery to Leeds. The locomotive was built by
Matthew Murray of Fenton, Murray and Wood.
It had double-acting cylinders and, unlike the Trevithick pattern, no
flywheel. The cylinders drove a geared wheel which engaged under the engine
with the rack. This design was quickly superseded following the discovery
the railroad tracktion properties by George Stephenson during construction
of the Stockton and Darlington Railway.
In 1812 the Middleton Railway which had been built to carry coal from
the pits to Leeds became to first railway to successfully use steam locomotives
on a commercial basis.The Stockton and Darlington Railway, ran in northern
England in the 1820s. This was soon followed by the Liverpool and Manchester
Railway, which proved the viability of rail transport, with George Stephenson's
famous Rocket steam locomotive. Railways soon spread throughout Britain
and through the world, and became the dominant means of land transport
for nearly a century, until the invention of aircraft and automobiles,
which prompted a gradual decline in railways.
Twin diesel locomotives of the Union Pacific refueling at Dunsmuir, CaliforniaThe
first railroad in the United States may have been a gravity railroad in
Lewiston, New York in 1764. The Leiper Railroad in Pennsylvania was the
first permanent railroad, opened in 1810, and the Granite Railroad in
1826 may have been the first to evolve through continuous operations into
a common carrier. The Baltimore and Ohio, opened in 1830, was the first
ton: Oldest railroads in North AmericaThe use of overhead wires conducting
electricity, invented by Granville T. Woods in 1888, amongst several other
improvements by Woods, led to the development of electrified railways,
the first of which was operated at Coney Island from 1892. Diesel and
electric trains and locomotives replaced steam in many countries in the
decades after World War II.Many countries since the 1960s have adopted
high-speed railways.On 24 August 2005 the Qingzang Railway became the
highest railway track in the world, when track was laid through the Tanggula
Mountain Pass at 5072 meters above sea level. [2]
Rail tracks
End of the single track, unelectrified line at Bad Radkersburg, Styria,
Austria, quite close to the Slovenian border.Main articles: Rail terminology,
and
In Britain and other Commonwealth of Nations countries the term railway
is used in preference to railroad, while in the United States the reverse
is true. However, railroad was used in Britain concurrently with railway
until the 1850s when railway became the established term. Furthermore
a number of American companies have railway in their names instead of
railroad, the BNSF Railway being the most pre-eminent modern example.
Further information: Usage of the terms railroad and railway
In Britain the term railway often refers to the complete organisation
of tracks, trains, stations, signalling, timetables andthe operating companies
that collectively make up a coordinated railway system, while permanent
way or p/way refers to the tracks alone.Rail transport in the United Kingdom
Subways, metros, elevated lines, trolley lines, and undergrounds are all
specialized railways. Further information:International railroad terminologyRail
transport by countryMain articles.
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