Tramway track

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"Tram track" redirects here. For the medical usage of the term, see Tram track (medicine).
Track gauges
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Graphic list of track gauges

Minimum
  Fifteen inch 381 mm (15 in)

Narrow
  Two foot and
600 mm
597 mm
600 mm
603 mm
610 mm
(1 ft 11 12 in)
(1 ft 11 58 in)
(1 ft 11 34 in)
(2 ft)
  750 mm,
Bosnian,
Two foot six inch,
800 mm
750 mm
760 mm
762 mm
800 mm
(2 ft 5 12 in)
(2 ft 5 1516 in)
(2 ft 6 in)
(2 ft 7 12 in)
  Swedish three foot,
900 mm,
Three foot
891 mm
900 mm
914 mm
(2 ft11 332 in)
(2 ft 11 716)
(3 ft)
  Metre 1,000 mm (3 ft 3 38 in)
  Three foot six inch,
Cape, CAP, Kyōki
1,067 mm (3 ft 6 in)
  Four foot six inch 1,372 mm (4 ft 6 in)

  Standard 1,435 mm (4 ft 8 12 in)

Broad
  Russian,
Five foot
1,520 mm
1,524 mm
(4 ft 11 2732 in)
(5 ft)
  Irish 1,600 mm (5 ft 3 in)
  Iberian 1,668 mm (5 ft 5 2132 in)
  Indian 1,676 mm (5 ft 6 in)
  Brunel 2,140 mm (7 ft 14 in)
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Conversion (list) · Bogie exchange · Variable gauge
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North America · South America · Europe
World map, rail gauge by region

Tramway track is used on tramways or light rail operations. Grooved rails (or girder rails) are often used to provide a protective flangeway in the trackwork in city streets. Like standard rail tracks, tram tracks consist of two parallel steel rails.

Tram rails can be placed in several surfaces, such as with standard rails on sleepers like railway tracks, or with grooved rails on concrete sleepers into street surfaces (pavement) for street running. Another environmentally friendly or ecologically friendly alternative is to lay tracks into grass turf surfaces; this is known as grassed track (or track in a lawn), first used in Liverpool in 1924.

History[edit]

The first tramways were laid in 1832 in New York by John Stephenson, to assist horses pulling buses through dirt roads, especially in wet weather when muddy. By laying rails, a horse could easily pull a load of 10 tonnes rather than 1 tonne on a dirt road. The evolution of street tramway tracks paralleled the development from horse power to mechanical, especially electric power. In a dirt road, the rails needed a foundation, usually a mass concrete raft. Highway authorities often made tramway companies pave the rest of the road, usually with granite or similar stone blocks, an extra cost.

The first tramways had a rail projecting above the road surface, or a step set into the road, both of which were apt to catch the narrow tyres of horse-drawn carriages. The invention by Alphonse Loubat in 1852 of grooved rail enabled tramways to be laid without causing a nuisance to other road users, except unsuspecting cyclists, who could get their wheels caught in the groove.

Electrification[edit]

Electrification needed other developments, most notably heavier rails to cope with electric tramcars weighing 12 tonnes rather than the 4 tonne horse-drawn variety; switching points, as electric trams could not be pulled onto the correct track by horses; and the need for electrical connections, to provide the return path for the electric current, which was usually supplied through an overhead wire.

Cable haulage[edit]

Prior to the universal introduction of electric power, many tramways were cable hauled[citation needed], with a continuous cable carried in a conduit under the road, and with a slot in the road surface through which the tram could clasp the cable for motion. This system can still be seen in San Francisco in California as well as the system of the Great Orme in Wales. These needed a rather more substantial track formation.

Conduit and stud systems[edit]

In some cities where overhead electric cables were deemed intrusive, underground conduits with electrical conductors were used. Examples of this were New York, Washington DC, Paris, London, Brussels and Budapest. The conduit system of electrical power was very expensive to install and maintain, although Washington did not close until 1962. Attempts were made with alternative systems not needing overhead wires. There were many systems of “surface” contact, where studs were set in the road surface, and energised by a passing tram, either mechanically or magnetically to supply power through a skate carried under the tram. Unfortunately these systems all failed due to the problem of reliability and not always turning off after the tram had passed, resulting in the occasional electrocution of horses and dogs[citation needed]. In the last five years[when?] a new system of surface contact has been installed in the Bordeaux tramway by Alstom.

Grooved rail[edit]

See also Grooved rail
Cross-section of LR55 rail
Cross section of a grooved tram rail
Difference in form and profile of the wheel and the rail of a train (left, blue) and a tram (right, green).

A grooved rail, groove rail, or girder rail is a special rail with a groove designed for tramway or railway track in pavement or grassed surfaces (grassed track or track in a lawn). This was invented in 1852 by Alphonse Loubat, a French inventor who developed improvements in tram and rail equipment, and helped develop tram lines in New York City and Paris.

Other tram track profiles[edit]

An alternative to the conventional girder profiled grooved track is the LR55 profile. This is considerably cheaper and easier to install and maintain than conventional girder rail as it requires a smaller footprint foundation and existing utility services need not be disturbed.[1] There is also grooved block rail.[2]

Track gauge[edit]

Gallery[edit]

Grassed track 
Light rail tracks with concrete railroad ties (sleepers) 
Laying tram tracks on Sydney's original tram network 
Grooved rail gauntlet track 
Joining tram tracks using an exothermic weld 
A rough exothermic weld after removal of the mould 

See also[edit]

References[edit]

External links[edit]