Tramway track
Encyclopedia
Tramway track is used on tramways or light rail
Light rail
Light rail or light rail transit is a form of urban rail public transportation that generally has a lower capacity and lower speed than heavy rail and metro systems, but higher capacity and higher speed than traditional street-running tram systems...

 operations. Grooved rails (or girder rails) are often used in order to make street running feasible. Like standard rail tracks, tram tracks consist of two parallel
Parallel (geometry)
Parallelism is a term in geometry and in everyday life that refers to a property in Euclidean space of two or more lines or planes, or a combination of these. The assumed existence and properties of parallel lines are the basis of Euclid's parallel postulate. Two lines in a plane that do not...

 steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

 rails
Rail profile
The rail profile is the cross sectional shape of a railway rail, perpendicular to the length of the rail.In all but very early cast iron rails, a rail is hot rolled steel of a specific cross sectional profile designed for use as the fundamental component of railway track.Unlike some other uses of...

.

Tram rails can be placed in several surface
Surface
In mathematics, specifically in topology, a surface is a two-dimensional topological manifold. The most familiar examples are those that arise as the boundaries of solid objects in ordinary three-dimensional Euclidean space R3 — for example, the surface of a ball...

s, such as with standard rails
Rail profile
The rail profile is the cross sectional shape of a railway rail, perpendicular to the length of the rail.In all but very early cast iron rails, a rail is hot rolled steel of a specific cross sectional profile designed for use as the fundamental component of railway track.Unlike some other uses of...

 on sleepers
Railroad tie
A railroad tie/railway tie , or railway sleeper is a rectangular item used to support the rails in railroad tracks...

 like railway tracks, or with grooved rails on concrete
Concrete
Concrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...

 sleepers into street surfaces (pavement
Pavement (material)
Road surface or pavement is the durable surface material laid down on an area intended to sustain vehicular or foot traffic, such as a road or walkway. In the past cobblestones and granite setts were extensively used, but these surfaces have mostly been replaced by asphalt or concrete. Such...

) for street running. Another environmentally-friendly
Environmentalism
Environmentalism is a broad philosophy, ideology and social movement regarding concerns for environmental conservation and improvement of the health of the environment, particularly as the measure for this health seeks to incorporate the concerns of non-human elements...

 or ecologically-friendly
Ecology
Ecology is the scientific study of the relations that living organisms have with respect to each other and their natural environment. Variables of interest to ecologists include the composition, distribution, amount , number, and changing states of organisms within and among ecosystems...

 alternative is to lay tracks into grass
Grass
Grasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base. They include the "true grasses", of the Poaceae family, as well as the sedges and the rushes . The true grasses include cereals, bamboo and the grasses of lawns ...

 turf
Sod
Sod or turf is grass and the part of the soil beneath it held together by the roots, or a piece of thin material.The term sod may be used to mean turf grown and cut specifically for the establishment of lawns...

 surfaces; this is known as grassed track (or track in a lawn
Lawn
A lawn is an area of aesthetic and recreational land planted with grasses or other durable plants, which usually are maintained at a low and consistent height. Low ornamental meadows in natural landscaping styles are a contemporary option of a lawn...

), first used in Liverpool in 1924.

History

The first tramways were laid in 1832 in New York by John Stephenson
John Stephenson (coachbuilder)
John G. Stephenson , an American coachbuilder, invented and patented the first streetcar to run on rails in the United States. On 26 November 1832, the New York and Harlem Railroad was formally opened...

, 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
Alphonse Loubat
Alphonse Loubat was a French inventor who developed improvements in tram and rail equipment, and helped develop tram lines in New York City and Paris....

 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

Electrification
Electrification
Electrification originally referred to the build out of the electrical generating and distribution systems which occurred in the United States, England and other countries from the mid 1880's until around 1940 and is in progress in developing countries. This also included the change over from line...

 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
Overhead lines
Overhead lines or overhead wires are used to transmit electrical energy to trams, trolleybuses or trains at a distance from the energy supply point...

.

Cable haulage

Prior to the universal introduction of electric power, many tramways were cable
Wire rope
thumb|Steel wire rope Wire rope is a type of rope which consists of several strands of metal wire laid into a helix. Initially wrought iron wires were used, but today steel is the main material used for wire ropes....

 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
Cable car (railway)
A cable car or cable railway is a mass transit system using rail cars that are hauled by a continuously moving cable running at a constant speed. Individual cars stop and start by releasing and gripping this cable as required...

 can still be seen in San Francisco
San Francisco cable car system
The San Francisco cable car system is the world's last permanently operational manually operated cable car system, in the US sense of a tramway whose cars are pulled along by cables embedded in the street. It is an icon of San Francisco, California...

 in California as well as the system
Funicular
A funicular, also known as an inclined plane or cliff railway, is a cable railway in which a cable attached to a pair of tram-like vehicles on rails moves them up and down a steep slope; the ascending and descending vehicles counterbalance each other.-Operation:The basic principle of funicular...

 of the Great Orme
Great Orme Tramway
The Great Orme Tramway is a cable-hauled gauge tramway in Llandudno in north Wales.This is Great Britain's only remaining cable operated street tramway and one of only three surviving in the world . It takes passengers from Llandudno Victoria Station to just below the summit of the Great Orme...

 in Wales. These needed a rather more substantial track formation.

Conduit and stud systems

In some cities where overhead electric cables were deemed intrusive, underground conduits
Conduit current collection
Conduit current collection is a system of electric current collection used by electric trams, where the power supply is carried in a channel under the roadway, rather than located overhead.-Description:...

 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
Stud contact system
The Stud Contact System is a once-obsolete ground-level power supply system for electric trams. Power supply studs were set in the road at intervals and connected to a buried electric cable by switches operated by magnets on the tramcars. Current was collected from the studs by a "skate" or "ski...

 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
Ground-level power supply
Ground-level power supply, also known as surface current collection and Alimentation par Sol is a modern method of third-rail electrical pick-up for street trams. It was invented for the Bordeaux tramway, which was constructed from 2000 and opened in 2003. Until 2011, this is the only place it is...

 has been installed in the Bordeaux tramway by Alstom.

Grooved rail

A grooved rail, groove rail, or girder rail is a special rail designed for tramway or railway track in pavement or grassed surfaces (grassed track or track in a lawn
Lawn
A lawn is an area of aesthetic and recreational land planted with grasses or other durable plants, which usually are maintained at a low and consistent height. Low ornamental meadows in natural landscaping styles are a contemporary option of a lawn...

). This was invented in 1852 by Alphonse Loubat
Alphonse Loubat
Alphonse Loubat was a French inventor who developed improvements in tram and rail equipment, and helped develop tram lines in New York City and Paris....

, 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

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.

Gallery

See also

  • Difference between train and tram rails
    Difference between train and tram rails
    A railroad or railway is a track where the vehicle travels over two parallel steel bars, called rails. The rails support and guide the wheels of the vehicles, which are traditionally either trains and trams. Modern light rail is a relatively new innovation which combines aspects of those two...

  • Grade (slope)
  • History of Trams
    History of Trams
    Tram, streetcar or trolley systems were common throughout the industrialized world in the late 19th and early 20th centuries, but they disappeared from many cities in the mid-20th century. In recent years, they have made a comeback...

  • Minimum railway curve radius
    Minimum railway curve radius
    The minimum railway curve radius, the shortest design radius, has an important bearing on constructions costs and operating costs and, in combination with superelevation in the case of train tracks, determines the maximum safe speed of a curve. Superelevation is not a factor on tramway tracks...


  • Rail profile
    Rail profile
    The rail profile is the cross sectional shape of a railway rail, perpendicular to the length of the rail.In all but very early cast iron rails, a rail is hot rolled steel of a specific cross sectional profile designed for use as the fundamental component of railway track.Unlike some other uses of...

  • Railroad switch
    Railroad switch
    A railroad switch, turnout or [set of] points is a mechanical installation enabling railway trains to be guided from one track to another at a railway junction....

     (points)
  • Reserved track
    Reserved track
    In tram transport terminology reserved track is track on ground exclusively for trams. Unlike track on streets and roads, reserved track does not need to take into account the transit of other wheeled vehicles, pedestrians, bicyclists or horses...


  • Street running
    Street running
    On-street running or street running is when a railroad track or tramway track runs directly along city streets, without any separation. The rails are embedded in the road....

  • Track transition curve
    Track transition curve
    A track transition curve, or spiral easement, is a mathematically calculated curve on a section of highway, or railroad track, where a straight section changes into a curve. It is designed to prevent sudden changes in centripetal force...

  • Tramway (industrial)
  • Tram tracking
    Tram tracking
    Tram tracking is a phrase used to describe findings in medical conditions that bear some resemblance to tramway tracks.-Pulmonology:Tram tracking is a radiologic sign seen with pulmonary edema due to congestive heart failure and in Bronchiectasis...



External links

  • ThyssenKrupp handbook ( only and registration required to view) (Besides Vignoles rails it shows special grooved girder rail for tramway tracks in pavement
    Pavement (material)
    Road surface or pavement is the durable surface material laid down on an area intended to sustain vehicular or foot traffic, such as a road or walkway. In the past cobblestones and granite setts were extensively used, but these surfaces have mostly been replaced by asphalt or concrete. Such...

    ). This website no longer provides the dimensional tables it used to provide.
  • LR55 Track System Full details
  • LR55 track suppliers and advisers
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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