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Standard gauge
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The standard gauge (also named the Stephenson gauge after George Stephenson, or Normal gauge) is a widely-used rail gauge. Approximately 60% of the world's existing railway lines are built to this gauge (see the list of countries that use the standard gauge). The distance between the inside edges of the rails of standard gauge track is .
ailways developed and expanded one of the key issues to be decided was that of the rail gauge (the distance, or width, between the inner sides of the rails) that should be used.
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Encyclopedia
The standard gauge (also named the Stephenson gauge after George Stephenson, or Normal gauge) is a widely-used rail gauge. Approximately 60% of the world's existing railway lines are built to this gauge (see the list of countries that use the standard gauge). The distance between the inside edges of the rails of standard gauge track is .
History
As railways developed and expanded one of the key issues to be decided was that of the rail gauge (the distance, or width, between the inner sides of the rails) that should be used. The eventual result was the adoption throughout a large part of the world of a "standard gauge" of , allowing inter-connectivity and the inter-operability of trains.
In England some early lines in colliery (coal mining) areas in the north east of the country were built to a gauge of ; and in Scotland some early lines were (Scotch gauge). By 1846, in both countries, these lines were widened to standard gauge. Parts of the United States rail system, mainly in the northeast, adopted the same gauge because some early trains were purchased from Britain. However, until well into the second half of the 19th century Britain and the USA had several different track gauges. The American gauges slowly converged as the advantages of equipment interchange became more and more apparent; the destruction of much of the South's broad gauge system in the American Civil War hastened this trend.
Origins
A popular legend traces the origin of the gauge even further back than the coalfields of northern England, pointing to the evidence of rutted roads marked by chariot wheels dating from the Roman Empire. This legend has been debunked. The historical tendency to place the wheels of horse-drawn vehicles approximately apart probably derives from the width needed to fit a carthorse in between the shafts. In addition, while road-traveling vehicles are typically measured from the outermost portions of the wheel rims (and there is some evidence that the first railroads were measured in this way as well), it became apparent that for vehicles travelling on rails, it was better to have the wheel flanges located inside the rails, and thus the distance measured on the inside of the wheels (and, by extension, the inside faces of the rail heads) was the important one.
There was no standard gauge for horse railways, but there were rough groupings: in the north of England none were less than 4ft. Wylam colliery's system, built before 1763, was 5 ft 0 in; as was John Blenkinsop's Middleton Railway, the old 4ft plateway was relaid to 5ft so that Blenkinsop's engine could be used. Others were 4 ft 4 in Beamish or 4ft 7.5in (Bigges Main and Kenton and Coxlodge).
The English railway pioneer George Stephenson spent much of his early engineering career working for the coal mines of County Durham. He favoured 4 ft 8 in for waggonways in Northumberland and Durham and used it on his Killingworth line. The Hetton and Springwell waggonways also used the gauge.
Stephenson's Stockton and Darlington railway (S&DR) was built primarily to transport coal from several mines near Shildon to the port at Stockton-on-Tees. The S&DR's initial track gauge of was set to accommodate the existing gauge of hundreds of horse-drawn that were already in use on the wagonways in the mines. It was built and used at this gauge for fifteen years before being changed to gauge.
The beginnings of the 4ft 8½in gauge
George Stephenson used the gauge (with an extra half-inch of free movement to reduce binding on curves) for the Liverpool and Manchester Railway, authorised in 1826 and opened 30 September 1830. The success of this project led to George Stephenson and his son Robert being employed to engineer several other larger railway projects. However, the Chester and Birkenhead Railway, authorised on 12 July 1837, was ; the Eastern Counties Railway, authorised on 4 July 1836, was ; London and Blackwall Railway, authorised on 28 July 1836, was 5 ft 0 in; the London and Brighton Railway, authorised on 15 July 1837, was 4 ft 9 in; the Manchester and Birmingham Railway, authorised on 30 June 1837, was 4 ft 9 in; the Manchester and Leeds Railway, authorised on 4 July 1836, was 4 ft 9 in the Northern and Eastern Railway, authorised on 4 July 1836, was 5 ft 0 in. The 4 ft 9 in railways were intended to take gauge vehicles and allow a running tolerance.
The influence of the Stephensons appears to be the main reason that the gauge became the standard, and its usage became more widespread than any other gauge. .
The Royal Commission
In the United Kingdom of Great Britain and Ireland, a Royal Commission in 1845 reported in favour of a standard gauge. In Great Britain, Stephenson's gauge was chosen as the standard gauge on the grounds that lines built to this gauge were eight times longer than that of the rival gauge, adopted principally by the Great Western Railway. The subsequent Gauge Act ruled that new passenger-carrying railways in Great Britain should be built to a standard gauge of ; and those in Ireland to a standard gauge . It allowed the broad gauge companies in Great Britain to continue repairing their tracks and expanding their networks within the Limits of Deviation and the exceptions defined in the Act. After an intervening period of mixed-gauge operation (tracks were laid with three running-rails), the Great Western Railway finally converted its entire network to standard gauge in 1892.
Pioneer lines
John Whitton, the longest serving engineer of the New South Wales Railways, was always being pressured to cut costs on new construction, by using horses or by using a narrower gauge. He resisted as much as possible so as to avoid any wasteful breaks-of-gauge, but did eventually introduce so-called pioneer lines for more remote and lightly trafficked areas to reduce costs. These lines eliminated extravagances like fencing, used half-round sleepers, light rails and replaced metal ballast with earth or ash. Speeds and axleloads and train loads were thus limited.
Only if traffic increased would these lines be upgraded to normal standards of construction. Indeed as the country was developed, many lines including those not of the pioneer type have seen their rail weights increase to allow heavier axleload, heavier engines and heavier and faster trains, all of which can be done progressively and incremenatlly without any need to change the gauge.
See also
Further reading
External links
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