Tramway track

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

Track gauge

By transport mode
Tram Rapid transit Miniature Scale model
By size (list)
Minimum   Minimum   Fifteen inch 381 mm (15 in) Narrow   600 mm Two foot Two foot three inch 600 mm 610 mm 686 mm (1 ft 11+5⁄8 in) (2 ft) (2 ft 3 in)   750 mm Bosnian gauge Two foot six inch 750 mm 760 mm 762 mm (2 ft 5+1⁄2 in) (2 ft 5+15⁄16 in) (2 ft 6 in)   Swedish three foot 900 mm Three foot Italian metre 891 mm 900 mm 914 mm 950 mm (2 ft 11+3⁄32 in) (2 ft 11+7⁄16 in) (3 ft) (3 ft1+13⁄32 in)   Metre 1,000 mm (3 ft 3+3⁄8 in)   Three foot six inch 1,067 mm (3 ft 6 in)   Four foot 1,219 mm (4 ft)   Four foot six inch 1,372 mm (4 ft 6 in)   1432 mm 1,432 mm (4 ft 8+3⁄8 in)   Standard 1,435 mm (4 ft 8+1⁄2 in) Broad   Italian broad gauge Dresden gauge 1,445 mm 1,450 mm (4 ft 8+7⁄8 in) (4 ft 9+3⁄32 in)   Leipzig gauge 1,458 mm (4 ft 9+13⁄32 in)   Toronto gauge 1,495 mm (4 ft 10+7⁄8 in)   1520 mm Five foot 1,520 mm 1,524 mm (4 ft 11+27⁄32 in) (5 ft)   Pennsylvania gauge Pennsylvania gauge Five foot three inch 1,581 mm 1,588 mm 1,600 mm (5 ft 2+1⁄4 in) (5 ft 2+1⁄2 in) (5 ft 3 in)   Baltimore gauge 1,638 mm (5 ft 4+1⁄2 in)   Iberian gauge Five foot six inch 1,668 mm 1,676 mm (5 ft 5+21⁄32 in) (5 ft 6 in)   Six foot 1,829 mm (6 ft)   Brunel 2,140 mm (7 ft 1⁄4 in)
Change of gauge
Break-of-gauge Dual gauge Conversion list Bogie exchange Variable gauge
By location
North America South America Europe Australia

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 on 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. Tram rails in street have the disadvantage that they pose a risk to cyclists. An 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

Tramway tracks are in existence since mid-16th century. Earlier they were made up of wood, but later during late 18th century iron and later steel came into use prominently.

The first street tramways were laid in 1832 in New York by John Stephenson to assist horses pulling buses on dirt roads, especially when the roads were muddy from wet weather. The rails enabled a horse to easily pull a load of 10 tonnes compared to 1 tonne on a dirt road. The evolution of street tramway tracks paralleled the transition from horse power to mechanical and 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, at 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.

Grooved rail

See also: Rail profile § Grooved rail

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). The rail has the railhead on one side and the guard on the other. The guard provides accommodation for the flange. The guard carries no weight, but may act as a checkrail.

Grooved rail 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. The invention 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. The grooves may become filled with gravel and dirt (particularly if infrequently used or after a period of idleness) and need clearing from time to time, this being done by a "scrubber" tram. Failure to clear the grooves can lead to a bumpy ride for the passengers, damage to either wheel or rail and possibly derailing.

Girder guard rail

The traditional form of grooved rail is the girder guard section illustrated below. This rail is a modified form of flanged rail and requires a special mounting for weight transfer and gauge stabilisation. If the weight is carried by the roadway subsurface, steel ties are needed at regular intervals to maintain the gauge. Installing these means that the whole surface needs to be excavated and reinstated.

Block rail

Block rail is a lower profile form of girder guard rail with the web is eliminated. In profile it is more like a solid form of bridge rail with a flangeway and guard added. Simply removing the web and combining the head section directly with the foot section would result in a weak rail, so additional thickness is required in the combined section.

• 
  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)

Track gauge

Main article: List of tram track gauges

Electrification

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.

Conduit and stud systems

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. In the last five years a new system of surface contact has been installed in the Bordeaux tramway by Alstom.

Cable haulage

Prior to the universal introduction of electric power, many tramways were cable hauled, 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.

Gallery

• 
  Grooved rail gauntlet track
• 
  Grassed track
• 
  Light rail tracks with concrete railroad ties (sleepers)
• 
  Joining tram tracks using an exothermic weld
• 
  A rough exothermic weld after removal of the mould
• 
  An intersection with the pavement removed, as workers repair the tracks for the Toronto streetcar system.

See also

• Difference between train and tram rails
• Grade (slope)
• Minimum railway curve radius
• Rail profile
• Railroad switch (points)
• Reserved track
• Street running
• Track transition curve
• Tram track gauge
• Tramway (industrial)

External links

Media related to Tram tracks at Wikimedia Commons

• LR55 Track System Full details
• LR55 track suppliers and advisers
• European Girder Guard Rail Sections and Tram/Street Car Grooved BLOCK Rail without Web
• Testing Girder Rail on the MBTA.
• Wirth Girder Rail
• Grooved or girder rail
• MRT Track & Services Co., Inc / Krupp, T and girder rails, scroll down.
• Block rails
• ThyssenKrupp grooved rail
• Hilton, George W.; Due, John Fitzgerald (1 January 2000). The Electric Interurban Railways in America. Stanford University Press. ISBN 978-0-8047-4014-2. Retrieved 10 June 2014. {{cite book}}: Cite has empty unknown parameter: |1= (help)