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Tramway track is used on tramways or light rail operations. As with standard rail tracks, tram tracks have two parallel steel rails, the distance between the heads of the rails being the track gauge. When there is no need for pedestrians or road vehicles to traverse the track, conventional flat-bottom rail is used. However, when such traffic exists, such as in urban streets, grooved rails are used.
Tram rails can be placed on several surfaces, such as on ground over which track ballast topped by sleepers (US: ties) and flat-bottom rails are laid – as with railway tracks – or, for street running, with grooved rails usually embedded into a concrete pavement. In some places, tracks are laid into grass turf surfaces; they are known as green track , grassed track or track in lawn .
Tramway tracks have been in existence since the mid-16th century. They were made of wood, but during the late 18th century iron and later steel came into use and then predominated.
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.
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 head on the right-hand side of the rail bears the vehicle's weight. The guard on the left-hand side, which has ample room for wheel flanges, carries no weight but serves to minimize the chance of derailment if the wheel were to be deflected from its normal position in which the flange is not laterally constrained.
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.
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 is a lower profile form of girder guard rail, where 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. [1]
A modern version of the grooved block rail has a lower mass and is inserted into a prefabricated spanning concrete girder such as the LR55 [2] without web but fully supported by noise reducing polyurethane grout or a girder rail such as P-CAT City Metro [3] is embedded. The prefabricated units if used with ultra light trams can be embedded into existing road base with possibly a reduced requirement for underground services diversions.
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.
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 ] Since 2003, a new system of surface contact has been installed in the Bordeaux tramway by Alstom.
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.
Rail transport is a means of transport using wheeled vehicles running in tracks, which usually consist of two parallel steel rails. Rail transport is one of the two primary means of land transport, next to road transport. It is used for about 8% of passenger and freight transport globally, thanks to its energy efficiency and potentially high speed.
A tram is a type of urban rail transit consisting of either individual railcars or self-propelled multiple unit trains that run on tramway tracks on urban public streets; some include segments on segregated right-of-way. The tramlines or tram networks operated as public transport are called tramways or simply trams/streetcars. Due to their close similarities, trams are commonly included in the wider term light rail, which also includes systems separated from other traffic.
A railway track or railroad track, also known as a train track or permanent way, is the structure on a railway or railroad consisting of the rails, fasteners, railroad ties and ballast, plus the underlying subgrade. It enables trains to move by providing a dependable surface for their wheels to roll upon. Early tracks were constructed with wooden or cast iron rails, and wooden or stone sleepers; since the 1870s, rails have almost universally been made from steel.
A third rail, also known as a live rail, electric rail or conductor rail, is a method of providing electric power to a railway locomotive or train, through a semi-continuous rigid conductor placed alongside or between the rails of a railway track. It is used typically in a mass transit or rapid transit system, which has alignments in its own corridors, fully or almost fully segregated from the outside environment. Third-rail systems are usually supplied from direct current electricity.
The railway track or permanent way is the elements of railway lines: generally the pairs of rails typically laid on the sleepers or ties embedded in ballast, intended to carry the ordinary trains of a railway. It is described as a permanent way because, in the earlier days of railway construction, contractors often laid a temporary track to transport spoil and materials about the site; when this work was substantially completed, the temporary track was taken up and the permanent way installed.
Ground-level power supply, also known as surface current collection or, in French, alimentation par le sol, is a concept and group of technologies whereby electric vehicles collect electric power at ground level from individually-powered segments instead of the more common overhead lines. Ground-level power supply was developed for aesthetic reasons, to avoid the presence of overhead lines in city centres.
Conduit current collection is an obsolete system that was used by some electric tramways to pass current to streetcars via a "conduit", a small tunnel under the roadway. Modern systems fall under the term ground-level power supply.
A horsecar, horse-drawn tram, horse-drawn streetcar (U.S.), or horse-drawn railway (historical), is an animal-powered tram or streetcar.
Trams in India were established in the late 19th century. Horse-drawn trams were introduced in Kolkata in 1873; in Mumbai, trams began operations in 1874; in Nashik in 1889; electric trams began in Chennai in 1895, and trams were also introduced in Kanpur and Delhi. They were discontinued in all Indian cities between 1933 and 1964, except for Kolkata.
The Great Orme Tramway is a cable-hauled 3 ft 6 in gauge tramway in Llandudno in north Wales. Open seasonally from late March to late October, it takes over 200,000 passengers each year from Llandudno Victoria Station to just below the summit of the Great Orme headland. From 1932 onwards it was known as the Great Orme Railway, reverting to its original name in 1977.
A rut is a depression or groove worn into a road or path by the travel of wheels or skis. Ruts can be formed by wear, as from studded snow tires common in cold climate areas, or they can form through the deformation of the asphalt concrete, pavement or subbase material. In modern roads the main cause is heavily loaded trucks. These heavy loaded trucks imprint their tire impressions on roads over time, causing ruts. Rut is a common pavement distress and is often used in pavement performance modeling.
Tramways are lightly laid industrial railways, often not intended to be permanent. Originally, rolling stock could be pushed by humans, pulled by animals, cable-hauled by a stationary engine, or pulled by small, light locomotives. Tramways can exist in many forms; sometimes simply tracks temporarily placed on the ground to transport materials around a factory, mine or quarry. Many use narrow-gauge railway technology, but because tramway infrastructure is not intended to support the weight of vehicles used on railways of wider track gauge, the infrastructure can be built using less substantial materials, enabling considerable cost savings.
The rail profile is the cross sectional shape of a railway rail, perpendicular to its length.
The history of trams, streetcars, or trolleys began in the early nineteenth century. It can be divided up into several discrete periods defined by the principal means of motive power used.
The stud contact system is an 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 collector" under the tramcar. The system was popular for a while in the early 1900s but soon fell out of favour because of the unreliability of the magnetic switches, largely due to friction and rapid corrosion affecting its cast iron moving components.
Trams in France date from 1837 when a 15 km steam tram line connected Montrond-les-Bains and Montbrison in the Loire. With the development of electric trams at the end of the 19th century, networks proliferated in French cities over a period of 15 years. Although nearly all of the country's tram systems were replaced by bus services in the 1930s or shortly after the Second World War, France is now in the forefront of the revival of tramways and light rail systems around the globe. Only tram lines in Lille and Saint-Étienne have operated continuously since the 19th century; the Marseille tramway system ran continuously until 2004 and only closed then for 3 years for extensive refurbishment into a modern tram network. Since the opening of the Nantes tramway in 1985, more than twenty towns and cities across France have built new tram lines. As of 2024, there are 28 operational tram networks in France, with 3 more planned. France is also home to Alstom, a leading tram manufacturer.
Baulk road is the name given to a type of railway track or 'rail road' that is formed using rails carried on continuous timber bearings, as opposed to the more familiar 'cross-sleeper' track that uses closely spaced sleepers or ties to give intermittent support to stronger rails.
A railway or railroad 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 or trams. Modern light rail is a relatively new innovation which combines aspects of those two modes of transport. However fundamental differences in the track and wheel design are important, especially where trams or light railways and trains have to share a section of track, as sometimes happens in congested areas.
Old Cleveland Road Tramway Tracks is a heritage-listed tramway along Old Cleveland Road in Camp Hill and Carina, adjoining suburbs in the City of Brisbane, Queensland, Australia. It was built in 1948 by Brisbane City Council. It is also known as Belmont Electric Tramway. It was added to the Queensland Heritage Register on 24 March 2000.
Green track is a type of railway track in which the track bed and surrounding area are planted with grass turf or other vegetation as ground cover. It is a popular way of making railways more visually appealing, particularly for trams and light rail, and providing additional urban green space. Aside from the visual improvement, the vegetation provides a number of positive effects, such as noise reduction, less air pollution, rainwater runoff mitigation, and reduced urban heat island effect.
Media related to Tram tracks at Wikimedia Commons