Rail transport

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Rail transport is the conveyance of passengers and goods by means of wheeled vehicles running along railways (railroads). Rail transport is part of the logistics chain, which facilitates international trade and economic growth.

Typical railway tracks consist of two parallel rails, normally made of steel, secured to crossbeams, termed sleepers (U.K., Commonwealth nations and Australia) or crossties or ties (U.S. and Canada). The sleepers maintain a constant distance between the two rails, a measurement known as the "gauge" of the track. To maintain the alignment of the track it is either laid on a bed of ballast or secured to a solid concrete foundation. The whole is referred to as permanent way (U.K. and Australia) or right-of-way (North America).

Railway rolling stock, which is fitted with metal wheels, moves with low frictional resistance when compared with road vehicles. Locomotives and powered cars normally rely on the point of contact of the wheel with the rail for traction and adhesion (the part of the transmitted axle load that makes the wheel "adhere" to the smooth rail). This is usually sufficient under normal conditions, but adhesion can be reduced or lost through the presence of unwanted material on the rail surface, such as moisture, grease, ice or dead leaves.^[1] To counteract such reduction of adhesion, many locomotives have devices which blow fine sand on the rail ahead of the wheels.

Contents 1 General 1.1 Incidence 1.2 Terminology 2 History 2.1 Stone rails 2.2 Wooden rails 3 Iron plate rail 3.1 Edge rail 3.2 Wrought iron and steel 4 Motive power 4.1 Steam locomotives 4.2 Dieselisation 4.3 Electrification 4.4 Miscellaneous 5 Operations 5.1 Rolling stock 5.2 Signalling 5.3 Right of way 5.4 Safety and railway disasters 6 Trackage 6.1 Track components 6.2 Points (turnouts or switches) 6.3 Maintenance 7 Terminology 8 Rail transport by country 9 See also 10 Footnotes 11 References 12 Further reading

[edit] General

Rail transport is an energy-efficient ^[3] and capital-intensive means of mechanised land transport and is a component of logistics. Along with various engineered components, rails constitute a large part of the permanent way. They provide smooth and hard surfaces on which the wheels of the train can roll with a minimum of friction. As an example, a typical modern wagon can hold up to 113 tonnes of freight on two four-wheel bogies or trucks. The contact area between each wheel and the rail is tiny, a strip no more than a few millimetres wide, which minimizes friction. The track distributes the weight of the train evenly, allowing significantly greater loads per axle and wheel than in road transport, leading to less wear and tear on the permanent way. This can save energy compared with other forms of transportation, such as road transport, which depends on the friction between rubber tires and the road. Trains have a small frontal area in relation to the load they are carrying, which reduces air resistance and thus energy usage, although this does not reduce the effects of side winds.

[edit] Incidence

Due to these benefits, rail transport is a major form of passenger and freight transport in many countries. In Asia, many millions use trains as regular transport in India, China, South Korea and Japan. It is widespread in European countries. Freight rail transport is widespread and heavily used in North America, but intercity passenger rail transport on that continent is relatively scarce outside the Northeast Corridor, although a number of major U.S. and Canadian cities have heavily-used local rail-based passenger transport systems or light rail or commuter rail operations.^[4]

Africa and South-America have some extensive networks such as in South Africa, Morocco-Algeria-Tunisia, Egypt, Brazil and Argentina; but some railroads on these continents are isolated lines connecting two places. Australia has a generally sparse network befitting its population density, but has some areas with significant networks, especially in the southeast. In addition to the previously existing east-west transcontinental line in Australia, a line from north to south was recently constructed. The highest railroad in the world is the line to Lhasa, Tibet, partly running over permafrost territory. In Western-Europe, the region with the highest railroad density in the world, most possible connections seem to have been made, but major projects continue to be realized, such as the Channel Tunnel between Britain and France, new dedicated high-speed lines, the Betuweroute for freight from the port of Rotterdam in Holland to Germany and the tunnel under Brussels. Western Europe nevertheless remains a technically and organisationally fragmented region with the Trans Europe Express being one of the few exceptions.

[edit] Terminology

The vehicles travelling on the rails, collectively known as rolling stock, are arranged in a linked series of vehicles called a train, which can include a locomotive if the vehicles are not individually powered. A locomotive (or "engine") is a powered vehicle used to haul a train of unpowered vehicles. In the U.S. individual unpowered vehicles are known generically as cars. These may be passenger-carrying or used for freight. For passenger-carrying vehicles the term carriage or coach is used, while a goods or freight-carrying vehicle is known as a freight car in the U.S. and a wagon or truck in the U.K. An individually-powered passenger vehicle is known as a railcar or a power car; when one or more as these are coupled to one or more unpowered trailer cars as an inseparable unit, this is called a railcar set or multiple unit. All rolling stock is fitted with standardized couplings (North America: couplers) to connect cars and locomotives together. In some countries, rolling stock is fitted with buffers to reduce the effect of hitting another car. Most rolling stock have brakes that can be operated remotely from the locomotive cab.

A station is the place where trains stop to load and unload, mostly referring to passengers. A railroad yard is an assembly of tracks for the purpose of storing rolling stock and assembling trains, or maintaining and repairing them, also called a shunt yard. Shunting (North America: switching) is arranging rolling stock in a yard, mostly performed by small locomotives called shunters (switchers or switching locomotives). Points or switches are the term used for changeable connections of two rails. The movement of trains is controlled by signals that may consist of lights or (movable) signs, manually or automatically operated. A tramway mostly refers to a passenger railway in the streets.

[edit] History

[edit] Stone rails

The earliest evidence of a railway is the 6-kilometre (3.7 mi) Diolkos wagonway, which transported boats across the Corinth isthmus in Greece during the 6th century BCE. Trucks pushed by slaves ran in grooves in limestone, which provided the track element, preventing the wagons from leaving the intended route. The Diolkos ran for over 1300 years, until 900 AD.^[5] The first horse-drawn wagonways also appeared in ancient Greece, with others on Malta and various parts of the Roman Empire, using cut-stone tracks. An example of stone track still exists on Dartmoor, England, where the Haytor Granite Tramway was built in 1820 using grooved granite blocks.

[edit] Wooden rails

Railways began reappearing in Europe after the Dark Ages following the collapse of the Roman Empire. The earliest known record of a railway in Europe from this period is a stained-glass window in the Minster of Freiburg im Breisgau dating from around 1350.^[6] By 1550, narrow gauge railways with wooden rails were common in mines in Europe.^[7] The first railways in the U.K. (also known as wagonways) were constructed in the early 17th century, mainly for transporting coal from mines to canal wharfs where it could be transferred to a boat for onward shipment. The earliest recorded examples are the Wollaton Wagonway in Nottinghamshire and the Bourtreehill - Broomlands Wagonway in Irvine, Ayrshire. Other examples were in Broseley in Shropshire, where wooden rails and flanged wheels were utilised, as on a modern railway. The rails were prone to wear out under the pressure, and had to be replaced regularly.

The earliest recorded railway in America was an inclined wooden tramway built by John Montresor (1736-1799), a British military engineer, in 1764. Called "The Cradles" and "The Old Lewiston Incline," loaded carts were pulled up wooden rails by rope. It facilitated the movement of goods over the Niagara Escarpment in present-day Lewiston, New York.^[8]

[edit] Iron plate rail

In 1768, the Coalbrookdale Iron Works laid cast iron plates on top of the wooden rails, providing a more durable load-bearing surface. These were later used by Benjamin Outram at his foundry in Ripley, Derbyshire, the first time standardised components were produced. It was these that led to the name "platelayer" for workers on the permanent way. The advantage was that a considerable variation in wheel spacing (gauge) could be accommodated. However, wheels would bind against the upright part of the plate, and mud and stones would accumulate. On the Little Eaton Gangway in 1799, where Outram used passing loops on the single track, moveable plates called "pointers" were provided, which became shortened to "points".^[9]

[edit] Edge rail

From the late 18th century, iron "edge rails" began to appear. The British civil engineer William Jessop designed smooth iron edge rails, which were used in conjunction with flanged iron wheels, introducing them on a route between Loughborough and Nanpantan, Leicestershire, as an adjunct to the Charnwood Forest Canal, in 1793-4.^[10] In 1803, Jessop opened the Surrey Iron Railway in south London, arguably the world's first horse-drawn public railway.^[11] Being of cast iron these rails were short, around three feet long, of a "fish-bellied" design. They had a foot at each end by means of which they were fastened to stone blocks in the ground.

[edit] Wrought iron and steel

Cast iron is a brittle material and the short lengths meant that they soon became uneven. However, developments in the process of hot rolling iron meant that longer length rails could be produced. In 1805, the first wrought iron rails were produced at Bedlington Ironworks near Durham. The first steel rails were produced by Robert Forester Mushet and laid at Derby station in 1857.^[10] Modern railways still use steel rails, typically welded together to form lengths of continuous welded rail; these remove the additional wear and tear on rolling stock caused by the tiny differences in rail surface height at the joints between rails.

[edit] Motive power

A locomotive is the part of the train that provides the power to move the load, whether it is freight or passenger cars. The railroad engineer or driver of the train controls the locomotive or other power cars. The locomotive is usually, but not always, the first car. In contrast, some trains have several powered, payload-carrying cars, and these may be referred to as multiple units, motor coaches or power cars. Their development was possible thanks to the rise of the electric or diesel engine that are small enough to build in or under a coach. This form of traction is increasingly common for passenger trains, but rare for freight trains.

[edit] Steam locomotives

The first locomotive to haul a train of wagons on rails was designed by Cornish engineer Richard Trevithick and was demonstrated in 1804 on a plateway at Merthyr Tydfil, South Wales.^[12] Although the locomotive successfully hauled the train, the rail design was not a success, partly because the locomotive's weight broke a number of the brittle cast-iron plates. Despite this setback, another area of South Wales pioneered rail operations when, in 1806, a horse-drawn railway was built between Swansea and Mumbles: the Swansea–Mumbles railway started carrying fare-paying passengers in 1807 – the first in the world to do so.^[13]

In 1811 John Blenkinsop designed the first successful and practical railway locomotive.^[14] He patented a system of moving coals by a rack railway worked by a steam locomotive (patent no. 3431), and a line was built connecting the Middleton Colliery to Leeds. The locomotive (The Salamanca) was built in 1812 by Matthew Murray of Fenton, Murray and Wood.^[15] The Middleton Railway was the first railway to successfully use steam locomotives on a commercial basis. It was also the first railway in Great Britain to be built under an Act of Parliament. Blenkinsop's engine had double-acting cylinders and, unlike the Trevithick pattern, no flywheel. Due to previous experience with broken rails, the locomotive was made very light in weight and this brought concerns about insufficient adhesion; so instead of driving the wheels directly, the cylinders drove a cogwheel through spur gears, the cogwheel providing traction by engaging with a rack cast into the side of the rail.

In Scotland, the Kilmarnock and Troon Railway was the first railway constructed, in 1811, authorised by Act of Parliament in 1808.^[16][17][18] The civil engineer leading the project was William Jessop, and it was the first railway in Scotland to use a steam locomotive, and the only line in Scotland for 14 years.^[19] Its representation appeared in the Coat of Arms of the Burgh of Troon.^[19] The line was intended to carry coal for the Duke of Portland; and ran services between Kilmarnock and Troon Harbour.^[16][17][18] The line began life as a 9.5 mile (16 km), double-track 4 ft 0 in (1,219 mm) gauge horse-drawn waggonway. It was built using cast iron plate rails with an inner flange. A George Stephenson-built locomotive, his second one from Killingworth Colliery, was tried on the main line in 1817, but the weight of the locomotive broke the cast iron plate rails. It worked better when wooden rails were used, and it remained in use until 1848.

The Stockton and Darlington Railway opened in northern England in 1825^[20] to be followed five years later by the Liverpool and Manchester Railway,^[21] considered to be the world's first inter-city line. The gauge was that used for the early wagonways, and had been adopted for the Stockton and Darlington Railway. The 4 ft 8½ in (1,435 mm) width became known as the international "standard gauge", used by about 60% of the world's railways. The Liverpool and Manchester Railway proved the viability of rail transport when, after organising the Rainhill Trials of 1829, Stephenson's Rocket successfully hauled a load of 13 tons at an average speed of 12 miles per hour. The company worked its trains from its opening entirely with steam traction. Railways soon spread throughout the U.K. and 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.

The first railroad in the U.S. may have been a gravity railroad in Lewiston, New York in 1764. The 1810 Leiper Railroad in Pennsylvania was intended as the first permanent railroad,^[22] and the 1826 Granite Railway in Massachusetts was the first commercial railroad to evolve through continuous operations into a common carrier. The Baltimore and Ohio, opened in 1830, was the first to evolve into a major system. In 1867, the first elevated railroad was built in New York. In 1869, the symbolically important transcontinental railroad was completed in the United States with the driving of a golden spike at Promontory, Utah.^[23] The development of the railroad in the United States helped reduce transportation time and cost, which allowed migration towards the west. Railroads increased the accessibility of goods to consumers, thus allowing individuals and capital to flow westward. Railroads created national markets characterized by the 'law of one price' by lowering difference in price charged for commodity between suppliers and demanders. Railroads increased social savings, and were the largest contributors of any innovation before 1900.

The first South American railway opened in 1854, when a line was laid between the Chilean towns of Caldera and Copiapo. The first concerted trans-Andine attempt between Argentina and Chile did not occur until the 1870s, due to the financial risks involved in such a project. It was not until 1887 that the Argentinians began to construct their part of the enterprise, with the Chileans beginning construction in 1889, though by 1893 work had ceased due to financial constraints. In 1896, the Transandine Railway Company was created in London to purchase the existing railways and construct a continuous line between Argentina and Chile that would improve transport and communication links in South America. This was finally completed in 1908, when the Argentine and Chilean stretches of track were joined.

[edit] Dieselisation

Dieselisation was the replacement of the steam locomotive with the diesel-electric locomotive (often referred to as a diesel locomotive), a process which began in the 1930s and is now substantially complete worldwide.

Dieselisation took place largely because of the reduction in operating costs it allowed. Steam locomotives require large pools of labour to clean, load, maintain and run. They also require extensive service, coaling and watering facilities. Diesel locomotives require significantly less time and labour to operate and maintain.

After World War II, dramatically increased labour costs in the Western World made steam an increasingly costly form of motive power. At the same time, the war had forced improvements in internal combustion engine technology that made diesel locomotives cheaper and more powerful. The post war world also re-aligned the business and financial markets, as did world geo-politics as in the Cold War (1947-1953).

[edit] Electrification

Robert Davidson started to experiment with an electrical railway car in Scotland in 1838. By 1839 he had completed and presented a 4.8 m long carriage that weighed six tons, including batteries. It reached a maximum speed of 6.4 kilometres per hour.

William Atcheson Traill built a hydro-electric generating station at Walkmill Falls, Bushmills for the Giant's Causeway tramway installing water turbines to produce the electrical power for his line. Because of legal problems over water rights, erection of the Bushmills turbines was delayed and when the first section of the tramway, from Portrush to Bushmills, was opened on 29 January 1883 the timetabled passenger traffic was handled by steam tram engines which were in any case necessary on the town section in Portrush where it was impossible to provide electric power since this was originally fed to the trains via an elevated third rail which ran alongside the line. The ceremonial opening, using electric traction, took place on 28 September 1883 although a full scheduled electric service did not begin until 5 November of that year.

Magnus Volk opened his electric railway in Brighton in 1883.

The use of overhead wires to conduct electricity, invented by Granville T. Woods in 1888, among several other improvements, led to the development of electrified railways, the first of which in the U.S. was at Coney Island in 1892. Richmond, Virginia had the first successful electrically-powered trolley system in the U.S. Designed by electric power pioneer Frank J. Sprague, the trolley system opened its first line in January 1888. Richmond's hills, long a transportation obstacle, were considered an ideal proving ground. The new technology soon replaced horse-powered streetcars.

Sweden got the perhaps first fully electrified developed railway that efficiently transported commuters as well as goods, in 1895. At the time it ran from central Stockholm to the newly founded suburb of Djursholm. It is a narrow gauge railway (3 Swedish ft/891 mm) that is partly still in use, and is now part of Roslagsbanan.

[edit] Miscellaneous

In the USSR the phenomenon of children's railways was developed in the 1930s (the world's first opened on 24 July 1935). Fully operated by children, they were extracurricular educational institutions, where teenagers learned railway professions. A lot of them are functioning in post-Soviet states and Eastern European countries.

Many countries since the 1960s have adopted high-speed railways. On 3 April 2007, a French TGV with a modified engine and wheels set a new train speed record of 574.8 km/h (357.2 mph). The record took place on the new LGV Est line between Paris and Strasbourg using a specially equipped TGV Duplex train. The overhead lines had been modified for the attempt to carry 31 kV rather than the normal 25 kV.^[24][25] On 24 August 2005 the Qingzang railway of China became the highest railway line in the world, when track was laid through the Tanggula Mountain Pass at 5072 m above sea level in the Tanggula Mountains in Tibet.^[26]

[edit] Operations

A railway can be broken down into two major components: the items which "move", also referred to as the rolling stock, which include locomotives, passenger carrying vehicles (or coaches) and freight carrying vehicles (or goods wagons); and the "fixed" components, usually referred to as the infrastructure, including the permanent way and ancillary buildings for railway functions.

[edit] Rolling stock

A locomotive is the vehicle that provides the motive power for a train. A locomotive has no payload capacity of its own, and its sole purpose is to move the train along the tracks. Usually, locomotives pull trains from the front, which gives better visibility to the driver, and allows faster speed.

A railroad car is a vehicle used for the haulage of either passengers or freight. Most cars carry a "revenue" load, although "non-revenue" cars exist for the railroad's own use, such as for maintenance-of-way purposes.

[edit] Signalling

Railway signalling is a system used to control railway traffic safely to prevent trains from colliding. Being guided by fixed rails, trains are uniquely susceptible to collision since they frequently operate at speeds that do not enable them to stop quickly or, in some cases, within the driver's sighting distance.

Most forms of train control involve movement authority being passed from those responsible for each section of a rail network (e.g., a signalman or stationmaster) to the train crew. The set of rules and the physical equipment used to accomplish this control determine what is known as the method of working (UK), method of operation (U.S.) or safeworking (Aus.). Not all methods require the use of signals, and some systems are specific to single track railways. The signalling process is traditionally carried out in a signal box (or interlocking tower (U.S.)), a small building that houses the lever frame required for the signalman to operate switches and signal equipment. These are placed at various intervals along the route of a railway, controlling specified sections of track. More recent technological developments have made such operational doctrine superfluous, with the centralization of signalling operations to regional control rooms. This has been facilitated by the increased use of computers, allowing vast sections of track to be monitored from a single location.

[edit] Right of way

Railway tracks are laid upon land owned or leased by the railway. Owing to the requirements for large radius turns and modest grades, rails will often be laid in circuitous routes. Public carrier railways are typically granted limited rights of eminent domain (U.K.:compulsory purchase). In many cases in the 19th century, railways were given additional incentives in the form of grants of public land. Route length and grade requirements can be reduced by the use of alternating earthen cut and fill, bridges, and tunnels, all of which can greatly increase the capital expenditures required to develop a right of way, while significantly reducing operating costs and allowing higher speeds on longer radius curves. In densely urbanized areas such as Manhattan, railways are sometimes laid in tunnels to minimize the effects on existing properties (see condemnation).

[edit] Safety and railway disasters

Trains can travel at very high speed, but they are heavy, are unable to deviate from the track and require a great distance to stop. Although rail transport is one of the safest forms of travel, there are many possibilities for accidents to take place. These can vary from the minor derailment (jumping the track), a head-on collision with another train and collision with an automobile or other vehicle at a level crossing/grade crossing. Level crossing collisions are relatively common in the United States where there are several thousand each year killing about 500 people (the comparable figures for the United Kingdom are 30 collisions and 12 casualties). For information regarding major accidents, see List of rail accidents.

The most important safety measures are railway signalling and gates at level/grade crossings. Train whistles warn of the presence of a train, while trackside signals maintain the distances between trains. In the United Kingdom, vandalism or negligence is thought responsible for about half of rail accidents.^{[citation needed]} Railway lines are zoned or divided into blocks guarded by combinations of block signals, operating rules, and automatic-control devices so that one train, at most, may be in a block at any time.

Historically, when a railway wished to construct a rail line that crossed an existing railway, an interlocking tower had to be constructed and manned, equipped with semaphore signals and derails controlled by rods and linkages. In this way a major accident could be avoided by signalling or derailling.^[27]

Compared with road travel, railways are safe. Annual death rates on roads are over 40,000 in the U.S., about 3,000 in the U.K. and 900 in Australia, compared with 1,000 rail-related fatalities in the U.S., under 20 in the U.K. and 10 in Australia.^[28][29] (These figures do not account for differences in passenger-miles traveled by mode; see e.g. Transportation safety in the United States.

[edit] Trackage

A typical track consists of two parallel steel (or in older networks, iron) rails, generally anchored perpendicular to members called crossties or sleepers of timber, concrete, or steel to maintain a consistent distance apart, or gauge. The rails and crossties (sleepers) are usually then placed on a foundation made of compressed earth on top of which is placed bed of ballast to distrubute the load from the crossties and to prevent the track from buckling (bending out of its original configuration) as the ground settles over time under the weight of the vehicles passing above. The vehicles traveling on the rails are arranged in a train; a series of individual powered or unpowered linked vehicles, displaying markers. These vehicles (referred to, in general, as cars, carriages or wagons) move with much less friction than do vehicles riding on rubber tires on a paved road, and the locomotive that pulls the train tends to use energy far more efficiently as a result.^{[citation needed]}

Trackage, consisting of railroad ties (sleepers) and ties and rails, may be prefabricated or assembled in place. Rails may be segments welded or bolted, and may be of a length comparable to that of a railcar or two or may be many hundreds of feet long.

On curves the outer rail may be at a higher level than the inner rail. This is called superelevation or cant. This reduces the forces tending to displace the track and makes for a more comfortable ride for standing livestock and standing or seated passengers. This will be effective at a limited range of speeds, however.

[edit] Track components

Railways are highly complex feats of engineering, with many hours of planning and forethought required for a successful outcome. The first component of a railway is the route, which is planned to provide the least resistance in terms of gradient and engineering works. As such, the track bed is heavily engineered to provide, where possible, a level surface. As such, embankments are constructed to support the track and to provide a compromise in terms of the route's average elevation. With this in mind, sundry structures such as bridges and viaducts are constructed in an attempt to maintain the railway's elevation, and gradients are kept within manageable constraints. Where such structures are not always justified, such as in hilly terrain where routes may require long detours to avoid such features, a cutting or tunnel is dug or bored through the obstacle. Once the sundry engineering works are completed, a bed of stone (ballast) is laid over the compacted track bed to enhance drainage around the ties and evenly distribute pressure over a wider area, locking the track-work in place. Crushed stone is firmly tamped to prevent further settling and to lock the stones. Minor water courses are channeled through pipes (culverts) before the grade is raised

The base of the trackage consists of treated wood, concrete or steel ties (sleepers). These ensure the proper distance between the rails (known as the track's "gauge"). Traditional US practice with wood sleepers is to anchor the rail structure to the road bed through the use of baseplates. These are attached to the top of the ties to provide a secure housing for the flat bottomed rails. After placement of the rail atop the plate, spikes are driven through holes in the plate and into the tie where they are held by friction. The top of the spike has a head that clamps the rail. As an alternative, lag bolts can be used to retain the clamps, which is preferred since screws are less likely to loosen. Traditional practice in the UK was to screw cast iron 'chairs' to wooden sleepers. These chairs loosely hold bullhead rail which is then secured by a wood or steel 'key' wedged between the side of the rail and the chair. With concrete or steel sleepers fixings are built into the sleeper to which flat bottom rail is attached with sprung steel clips.

The space between and surrounding the ties is filled with additional ballast to stabilize the rail assembly.

[edit] Points (turnouts or switches)

Points (U.K.) or switches (U.S.), technically known as turnouts, are the means of directing a train onto a diverging section of track, for example, a siding, a branch line, or a parallel running line. Laid similar to normal track, a point typically consists of a frog (common crossing), check rails and two switch rails. The switch rails may be moved left or right, under the control of the signalling system, to determine which path the train will follow.

[edit] Maintenance

Spikes in wooden ties can loosen over time, while split and rotten ties may be individually replaced with a new wooden tie or concrete substitute. Concrete ties can also develope cracks or splits, and can also be replaced individually. Should the rails settle due to soil subsidence, they can be lifted by specialized machinery and additional ballast tamped down to form a level bed. Periodically, ballast must be removed and replaced with clean ballast to ensure adequate drainage. Culverts and other passages for water must be kept clear lest water is impounded by the trackbed, causing landslips. Where trackbeds are placed along rivers, additional protection is usually placed to prevent erosion during times of high water, while bridges are another important item requiring inspection and maintenance. Besides general bridge maintenance, when a heavy train crosses a bridge at high speed, it can put a large surge of stress on the bridge in a short period of time, so bridges have to be inspected regularly for cracks and other stress damage.

[edit] Terminology

In the U.K. and most other Commonwealth countries the term railway is used, not the U.S. term railroad. In Canada railway and railroad are interchangeable, although in law railway is the usual term. ^[30] Railroad was used in the U.K. concurrently with railway until the 1850s when railway became the established term. Several American companies have railway in their official names instead of railroad, including two of major modern railroads, BNSF Railway Company and Norfolk Southern Railway Company.

In the U.K. the term railway often refers to the whole organization of tracks, trains, stations, signalling, timetables and the operating companies that collectively make up a coordinated railway system, while permanent way or p/way refers to the tracks alone (this terminology is not common outside of the railway industry or those who take a keen interest in it).

Rapid transit systems (subways, metros, elevated lines, and undergrounds) and trolley lines are all specialized railways.

[edit] Rail transport by country

Of 236 countries and dependencies, 143 have rail transport (including several with very little), of which about 90 have passenger services.^{[citation needed]}

[edit] See also

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This box: view • talk • edit

• List of rail transport topics

• Economy of Earth (Transportation section)
• High-speed rail
• Hillclimbing (railway)
  • Rack railway (Cog railway or Rack and pinion railway)
  • Funicular
  • Gravity railroad
  • Spiral (railway)
  • Zig Zag (railway)
• Industrial railway
• Infrastructure
• Intermodal freight transport
• Intermodal passenger transport
• Land speed record for railed vehicles
• List of heritage railways
• List of named passenger trains
• List of people associated with rail transport
• List of railway companies
• List of railway companies in Switzerland
• List of suburban and commuter rail systems
• Maglev train
• Plateway
• Private railroad
• Private transport
• Public transport
• Rail adhesion
• Railcar (self propelled transport)
• Rail gauge
• Rail Inspection
• Rail tracks
• Rail transport in fiction
• Rail transport modelling
• Railroad ecology
• Railroad police
• Railroad-related periodicals
• Railway car
• Railway electrification system
• Railway ferry
• Railway Mail Service
• Railway signal
• Railway signalling
• Rapid transit

[edit] Footnotes

[edit] References

• Cannon, John (Ed.): Oxford Companion to British History (Oxford: Oxford University Press, 2002) ISBN 0198608721

[edit] Further reading

• John H. Armstrong. Railroad: What It Is, What It Does 5th Edition (2008)
• Rainer Fremdling, "Railways and German Economic Growth: A Leading Sector Analysis with a Comparison to the United States and Great Britain," The Journal of Economic History, Vol. 37, No. 3. (September 1977), pp. 583-604.
• Leland H. Jenks, "Railroads as an Economic Force in American Development," The Journal of Economic History, Vol. 4, No. 1 (May 1944), 1-20.
• Lewis, M. J. T., "Railways in the Greek and Roman world", in Guy, A. / Rees, J. (eds), Early Railways. A Selection of Papers from the First International Early Railways Conference (2001), pp. 8–19 (10-15)
• John Marshall, The Guinness Railway Book (Enfield, 1989)
• O. S. Nock, ed. Encyclopedia of Railways (London, 1977), worldwide coverage, heavily illustrated
• Frederick Smeeton Williams, Our Iron Roads: Their History, Construction and Social Influences (1852) (available through google books).
• Patrick O’Brien. Railways and the Economic Development of Western Europe, 1830-1914 (1983)
• Jack Simmons and Gordon Biddle (editors), The Oxford Companion to British Railway History: From 1603 to the 1990s (2nd edition 1999)
• Skelton, Oscar D. (1916). The Railway Builders. Glasgow, Brook, & Company, Toronto. 
• John Stover, American Railroads (2nd ed 1997)
• James W. Ely Jr "Railroads & American Law" (2001) University Press of Kansas