Horseshoe curve (railway)
Encyclopedia
A horseshoe curve is a tight curve in a railway or a road
, through an angle in excess of 180 degrees. A horseshoe curve is a means to lengthen the passage of an ascending or descending grade, so as to reduce the maximum gradient of ascent or descent. The horseshoe refers to the U shaped bypass of a straight route. The straight route would be too steep to climb, so instead the route takes a more circuitous route. In the case of roads, such curves, if tight enough, are typically called hairpin turn
s.
The route deviation thus undertaken greatly lengthens the actual distance travelled, and by so doing, it allows the difference in altitude to be averaged over a much longer track length. This is similar to the way a spiral
works. However, a horseshoe curve does not involve the track crossing over itself, and the three main curves are only a part of a horseshoe, whereas a spiral is generally a continuous curvature. Another reason for a horseshoe curve is where the straight-ahead route involves bridging a deep gully. The deviation might allow the gully to be crossed at a more favourable location to one side.
Horseshoe curves are a common feature of railway lines in steeply graded or hilly country, where effective means have to be found to achieve an acceptable grade or construction cost of a line. Like spirals, the main limitation of the horseshoe is keeping the radius of the curvatures at or above a desirable minimum. Sharp curvatures will limit the speeds at which trains can run on a line.
Road
A road is a thoroughfare, route, or way on land between two places, which typically has been paved or otherwise improved to allow travel by some conveyance, including a horse, cart, or motor vehicle. Roads consist of one, or sometimes two, roadways each with one or more lanes and also any...
, through an angle in excess of 180 degrees. A horseshoe curve is a means to lengthen the passage of an ascending or descending grade, so as to reduce the maximum gradient of ascent or descent. The horseshoe refers to the U shaped bypass of a straight route. The straight route would be too steep to climb, so instead the route takes a more circuitous route. In the case of roads, such curves, if tight enough, are typically called hairpin turn
Hairpin turn
A hairpin turn , named for its resemblance to a hairpin/bobby pin, is a bend in a road with a very acute inner angle, making it necessary for an oncoming vehicle to turn almost 180° to continue on the road. Such turns in ramps and trails may be called switchbacks in American English, by analogy...
s.
The route deviation thus undertaken greatly lengthens the actual distance travelled, and by so doing, it allows the difference in altitude to be averaged over a much longer track length. This is similar to the way a spiral
Spiral (railway)
A spiral is a technique employed by railways to ascend steep hills.A railway spiral rises on a steady curve until it has completed a loop, passing over itself as it gains height, allowing the railway to gain vertical elevation in a relatively short horizontal distance...
works. However, a horseshoe curve does not involve the track crossing over itself, and the three main curves are only a part of a horseshoe, whereas a spiral is generally a continuous curvature. Another reason for a horseshoe curve is where the straight-ahead route involves bridging a deep gully. The deviation might allow the gully to be crossed at a more favourable location to one side.
Horseshoe curves are a common feature of railway lines in steeply graded or hilly country, where effective means have to be found to achieve an acceptable grade or construction cost of a line. Like spirals, the main limitation of the horseshoe is keeping the radius of the curvatures at or above a desirable minimum. Sharp curvatures will limit the speeds at which trains can run on a line.
America
- Cascade TunnelCascade TunnelThe Cascade Tunnel refers to two tunnels at Stevens Pass through the Cascade Mountains, approximately to the east of Everett, Washington. The first Cascade Tunnel was a 2.63-mile long single track railroad, built by the Great Northern Railway in 1900 to avoid problems caused by heavy winter...
has a gully on the western approaches that is an unnamed horseshoe curve. - Chorro, California near San Luis Obispo.
- Dunsmuir, CaliforniaDunsmuir, CaliforniaDunsmuir is a city in Siskiyou County, California, United States. The population was 1,650 at the 2010 census, down from 1,923 at the 2000 census. It is currently a hub of tourism in Northern California as visitors enjoy fishing, skiing, climbing, or sight-seeing...
has a pair of horseshoe curves nearby. Map - Horseshoe Curve (Pennsylvania)Horseshoe Curve (Pennsylvania)Horseshoe Curve is a famous railroad horseshoe curve in central Pennsylvania, near Altoona in the United States. Called an "engineering marvel", it was completed in 1854 by the Pennsylvania Railroad...
, at Kittanning GapKittanning GapKittanning Gap is a gap at the summit of Allegheny Ridge in central Pennsylvania in the United States. It is located in Logan Township, approximately 5 mi west of Altoona.-History:...
Asia
- Kamaishi LineKamaishi LineThe is a railway line operated by the East Japan Railway Company which runs 90.2 km between Hanamaki and Kamaishi in Iwate Prefecture, Japan.-Stations:All stations are in Iwate Prefecture.-See also:...
of East Japan Railway CompanyEast Japan Railway Companyis the largest passenger railway company in the world and one of the seven Japan Railways Group companies. The company name is officially abbreviated as JR East in English, and as in Japanese. The company's headquarters are in Yoyogi, Shibuya, Tokyo....
in JapanJapanJapan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
, has a horseshoe curve from Kamiarisu Station down to Rikuchū Ōhashi Station ("down" on the elevation and registration of direction of the line).
Australasia
- Picton railway station, New South WalesPicton railway station, New South Wales-Transport links:Picton Buslines runs seven routes to and from Picton railway station:*900 - to Campbelltown*901 - to Wilton and Douglas Park*911 - to Buxton and Bargo*912 - to Bargo and Yanderra*913 - to Buxton and Thirlmere...
, turns back on itself at about 225 degrees. - The Raurimu SpiralRaurimu SpiralThe Raurimu Spiral is a single-track railway spiral, starting with a horseshoe curve, overcoming a 132 m height difference, in the central North Island of New Zealand, on the North Island Main Trunk Railway. It is a notable feat of civil engineering, having been called an 'engineering masterpiece'...
in New Zealand has a horseshoe curve as the first part of the climb.
Europe
- DovrebanenDovrebanenThe Dovre Line is the main line of the Norwegian railway system between Oslo and Trondheim. The 64 km section south of Eidsvoll has been replaced by the Gardermo Line, the only high-speed line in the country. The line between Eidsvoll and Dombås is from old times the Eidsvoll–Dombås Line. The line...
, the main line of the Norwegian railway network, has a horseshoe from DombåsDombåsThe village of lies in the Dovre municipality and serves as an administrative center in the upper Gudbrandsdal, Norway. It lies at an important junction of roads: south leading to the current capital of Norway, Oslo, west via Lesja leading to Åndalsnes on the sea and north to the old capital,...
and up to the DovreDovrefjellDovrefjell is a mountain range in central Norway that forms a natural barrier between Eastern Norway and Trøndelag, the area around Trondheim. As a result, it has been heavily trafficked during and probably preceding historical times...
plateau. - FlåmsbanaFlåmsbanaThe Flåm Line is a long railway between Myrdal and Flåm in Aurland, Norway. As a branch line of the Bergen Line, it runs through Flåmsdalen and connects the mainline with Sognefjord. The line's elevation difference is . The line has ten stations, twenty tunnels and one bridge. It has a maximum...
, Norway, has a double horseshoe, one inside a tunnel, one in the open, few kilometres below top station. - GrybówGrybówGrybów is a town in the Nowy Sącz County, in Lesser Poland Voivodeship of Poland, with 12,409 inhabitants . It is located in the heartland of the Doły , and its average altitude is 370 metres above sea level, although there are some hills located within the confines of the city, Grybów has the...
, Poland has a horseshoe curve 2,5 km west of the town. - KaliszKaliszKalisz is a city in central Poland with 106,857 inhabitants , the capital city of the Kalisz Region. Situated on the Prosna river in the southeastern part of the Greater Poland Voivodeship, the city forms a conurbation with the nearby towns of Ostrów Wielkopolski and Nowe Skalmierzyce...
, Poland has a double horseshoe curve leading the tracks from a flat plateau down to the valley of ProsnaProsnaThe Prosna is a river in central Poland, a tributary of the Warta river , with a length of 217 kilometres and the basin area of 4,925 km2 .-Towns:*Gorzów Śląski*Praszka*Wieruszów*Grabów nad Prosną*Kalisz...
river. - Between Jelenia GóraJelenia Góra----Jelenia Góra is a city in Lower Silesia, south-western Poland. The name of the city means "deer mountain" in Polish, Czech and German. It is close to the Krkonoše mountain range running along the Polish-Czech border – ski resorts such as Karpacz and Szklarska Poręba can be found...
and Szklarska PorębaSzklarska PorebaSzklarska Poręba is a town in Jelenia Góra County, Lower Silesian Voivodeship, in south-western Poland. The town has a population of around 7,000...
in Poland there is a five-times, elongated horseshoe curve (50°51′19"N, 15°34′17"E). Map - The Rhein-Ruhr S-BahnRhein-Ruhr S-BahnThe Rhine-Ruhr S-Bahn is a polycentric S-Bahn network covering the Rhine-Ruhr Metropolitan Region in the German federal state of North Rhine-Westphalia. This includes most of the Ruhr , the Berg cities of Wuppertal and Solingen and parts of the Rhineland...
in GermanyGermanyGermany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
has a horseshoe curve in Neviges, VelbertVelbertVelbert is a town in the district of Mettmann, in North Rhine-Westphalia, Germany. Langenberg, a district of Velbert, is well known as the location of the Sender Langenberg transmitter site.-Geography:...
on the route between EssenEssen- Origin of the name :In German-speaking countries, the name of the city Essen often causes confusion as to its origins, because it is commonly known as the German infinitive of the verb for the act of eating, and/or the German noun for food. Although scholars still dispute the interpretation of...
and WuppertalWuppertalWuppertal is a city in North Rhine-Westphalia, Germany. It is located in and around the Wupper river valley, and is situated east of the city of Düsseldorf and south of the Ruhr area. With a population of approximately 350,000, it is the largest city in the Bergisches Land...
, known as the Prince William railway.