Hillclimbing (railway)
Encyclopedia
While railways have a great ability to haul very heavy loads, this advantage only really applies when the tracks are fairly level. As soon as the gradients stiffen, the tonnage that can be hauled is greatly diminished.
Where a railway has to cross a range of mountains, it is important to lower the summit as much as possible, as this reduces the steepness of the gradients on either side. This can be done with a summit tunnel or a deep summit cutting.
A summit tunnel
can lower the summit even more, and paradoxically, the steeper the hill, the shorter the tunnel tends to be; tunnels cost the same no matter how much overburden there is, while cuttings tend to increase in cost with the square of the overburden.
Care had to be taken with summit tunnels in the early days of steam with designs that suffered from problems with smoke and slippery rail.
of a section of railway line between two major stations is the gradient of the steepest stretch. The ruling gradient governs the tonnage of the load that the locomotive can haul reliably.
was built at a time when choice between locomotive and cable haulable was not clear cut. Therefore all hill climbing (1 in 100) sections was concentrated in one place where cable haulage by stationary engines could be used if necessary, while the rest of the line was engineered to be so gently graded (say 1 in 2000) that even primitive locomotives would have a chance of succeeding. As it turned out at the Rainhill Trials
of 1829, locomotives proved capable of handling the short 1.6-km length of 1 in 100 gradients on either side of the Rainhill level.
Since the early trains had primitive brakes, it was also necessary to have very gentle gradients to reduce the need for strong brakes. Sudden changes in gradients would have also overstressed the primitive coupling
s between the carriages.
The gentle 1 in 2000 gradients were made possible by very substantial earthworks and bridges.
also opened in 1830 but had gradients so steep - 1 in 8 - that cable haulage was essential. It hauled mainly coal.
http://www.wirksworth.org.uk/CHPR.htm
, a narrow gauge route across the Cornish peninsula (planned in 1818, opened in 1825) used a significant incline to access the harbour at Portreath
, which like many in Cornwall
sits in a steep valley.
(L&CR) of 1847 a deep cutting was cut at the Shap Summit. This cutting was cut through rock, about 0.5 mile (800 m) in length, and is between 50-60 feet (15-20 m) deep.
has the steepest gradient on any British railway at 1 in 17 (5.88%). A zig zag stripe has been welded to the rail surface to allow trains to gain a satisfactory grip, and prevent slipping.
Techniques to overcome steep hills
Some of the techniques that can be used to overcome steep hills include:- dividing the loadCargoCargo is goods or produce transported, generally for commercial gain, by ship, aircraft, train, van or truck. In modern times, containers are used in most intermodal long-haul cargo transport.-Marine:...
or splitting the trainTrainA train is a connected series of vehicles for rail transport that move along a track to transport cargo or passengers from one place to another place. The track usually consists of two rails, but might also be a monorail or maglev guideway.Propulsion for the train is provided by a separate...
, which requires a siding at the summit. - attaching additional banking engine(s)Bank engineA bank engine or helper engine or pusher engine is a railway locomotive that temporarily assists a train that requires additional power or traction to climb a grade...
. - replacing the engineLocomotiveA locomotive is a railway vehicle that provides the motive power for a train. The word originates from the Latin loco – "from a place", ablative of locus, "place" + Medieval Latin motivus, "causing motion", and is a shortened form of the term locomotive engine, first used in the early 19th...
with a more powerful heavier engine for the duration of the steep grade. - strengthening the track on or approaching the steep grade, allowing higher speeds, and allowing the train a run at the gradient.
- using two-in-one articulated locomotiveArticulated locomotiveArticulated locomotive usually means a steam locomotive with one or more engine units which can move independent of the main frame. This is done to allow a longer locomotive to negotiate tighter curves...
s such as the FairlieFairlieA Fairlie is a type of articulated steam locomotive that has the driving wheels on bogies. The locomotive may be double-ended or single ended...
, GarrattGarrattA Garratt is a type of steam locomotive that is articulated in three parts. Its boiler is mounted on the centre frame, and two steam engines are mounted on separate frames, one on each end of the boiler. Articulation permits larger locomotives to negotiate curves and lighter rails that might...
or Mallet locomotiveMallet locomotiveThe Mallet Locomotive is a type of articulated locomotive, invented by a Swiss engineer named Anatole Mallet ....
. - using a Booster engineBooster engineA booster engine for steam locomotives is a small two-cylinder steam engine back-gear-connected to the trailing truck axle on the locomotive or, if none, the lead truck on the tender. A rocking idler gear permits it to be put into operation by the engineer...
, though this is usually limited to starting the heavy train. - Zig ZagsZig Zag (railway)A railway zig zag, also called a switchback, is a way of climbing hills in difficult country with a minimal need for tunnels and heavy earthworks. For a short distance , the direction of travel is reversed, before the original direction is resumed.A location on railways constructed e.g...
- SpiralsSpiral (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...
- Horseshoe curvesHorseshoe curve (railway)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...
- Rack railwayRack railwayA rack-and-pinion railway is a railway with a toothed rack rail, usually between the running rails. The trains are fitted with one or more cog wheels or pinions that mesh with this rack rail...
- Fell mountain railway systemFell mountain railway systemThe Fell system uses a raised centre rail between the two running rails on steeply-graded railway lines to provide extra traction and braking, or braking alone. Trains are propelled by wheels or braked by shoes pressed horizontally onto the centre rail, as well as by means of the normal running...
- ElevatorElevatorAn elevator is a type of vertical transport equipment that efficiently moves people or goods between floors of a building, vessel or other structures...
s, cableCable railwayA cable railway is a steeply graded railway that uses a cable or rope to haul trains.-Introduction:...
railways, or funicularFunicularA 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...
railways driven by stationary engineStationary engineA stationary engine is an engine whose framework does not move. It is normally used not to propel a vehicle but to drive a piece of immobile equipment such as a pump or power tool. They may be powered by steam; or oil-burning or internal combustion engines....
s (cable haulage up and down inclines). - Geared steam locomotiveGeared steam locomotiveA geared steam locomotive is a type of steam locomotive which uses reduction gearing in the drivetrain, as opposed to the common directly driven design....
s such as a Shay locomotiveShay locomotiveThe Shay locomotive was the most widely used geared steam locomotive. The locomotives were built to the patents of Ephraim Shay, who has been credited with the popularization of the concept of a geared steam locomotive... - Atmospheric railwayAtmospheric railwayAn atmospheric railway uses air pressure to provide power for propulsion. In one plan a pneumatic tube is laid between the rails, with a piston running in it suspended from the train through a sealable slot in the top of the tube. Alternatively, the whole tunnel may be the pneumatic tube with the...
- Cable car (railway)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...
- Rail surface treatment
- CompensationCompensation (engineering)In engineering, compensation is planning for side effects or other unintended issues in a design. The design of an invention can itself also be to compensate for some other existing issue or exception....
for curvature - the gradient is slightly eased on sharpest curves so that the tractive effort to pull the train is uniform.
History
Early tramways and railways were laid out with very gentle grades because locomotive and horse haulage were so low in tractive effort. The only exception would be with a line that was downhill all the way for loaded traffic. Brakes were very primitive at this early stage.Where a railway has to cross a range of mountains, it is important to lower the summit as much as possible, as this reduces the steepness of the gradients on either side. This can be done with a summit tunnel or a deep summit cutting.
A summit tunnel
Tunnel
A tunnel is an underground passageway, completely enclosed except for openings for egress, commonly at each end.A tunnel may be for foot or vehicular road traffic, for rail traffic, or for a canal. Some tunnels are aqueducts to supply water for consumption or for hydroelectric stations or are sewers...
can lower the summit even more, and paradoxically, the steeper the hill, the shorter the tunnel tends to be; tunnels cost the same no matter how much overburden there is, while cuttings tend to increase in cost with the square of the overburden.
Care had to be taken with summit tunnels in the early days of steam with designs that suffered from problems with smoke and slippery rail.
Ruling gradient
The ruling gradientRuling gradient
The term "ruling grade" is usually used as a synonym for "steepest climb" between two points on a railroad. But if the steepest climb is, say, a quarter-mile of 2% upgrade preceded and followed by 1.5% grade the "ruling grade" can only be defined arbitrarily....
of a section of railway line between two major stations is the gradient of the steepest stretch. The ruling gradient governs the tonnage of the load that the locomotive can haul reliably.
Liverpool and Manchester Railway
The pioneering Liverpool and Manchester RailwayLiverpool and Manchester Railway
The Liverpool and Manchester Railway was the world's first inter-city passenger railway in which all the trains were timetabled and were hauled for most of the distance solely by steam locomotives. The line opened on 15 September 1830 and ran between the cities of Liverpool and Manchester in North...
was built at a time when choice between locomotive and cable haulable was not clear cut. Therefore all hill climbing (1 in 100) sections was concentrated in one place where cable haulage by stationary engines could be used if necessary, while the rest of the line was engineered to be so gently graded (say 1 in 2000) that even primitive locomotives would have a chance of succeeding. As it turned out at the Rainhill Trials
Rainhill Trials
The Rainhill Trials were an important competition in the early days of steam locomotive railways, run in October 1829 in Rainhill, Lancashire for the nearly completed Liverpool and Manchester Railway....
of 1829, locomotives proved capable of handling the short 1.6-km length of 1 in 100 gradients on either side of the Rainhill level.
Since the early trains had primitive brakes, it was also necessary to have very gentle gradients to reduce the need for strong brakes. Sudden changes in gradients would have also overstressed the primitive coupling
Coupling (railway)
A coupling is a mechanism for connecting rolling stock in a train. The design of the coupler is standard, and is almost as important as the railway gauge, since flexibility and convenience are maximised if all rolling stock can be coupled together.The equipment that connects the couplings to the...
s between the carriages.
The gentle 1 in 2000 gradients were made possible by very substantial earthworks and bridges.
Cromford and High Peak Peak Railway
The Cromford and High Peak RailwayCromford and High Peak Railway
The Cromford and High Peak Railway in Derbyshire, England, was completed in 1831, to carry minerals and goods between the Cromford Canal wharf at High Peak Junction and the Peak Forest Canal at Whaley Bridge -Origins:...
also opened in 1830 but had gradients so steep - 1 in 8 - that cable haulage was essential. It hauled mainly coal.
http://www.wirksworth.org.uk/CHPR.htm
Redruth and Chasewater Railway
The Redruth and Chasewater RailwayRedruth and Chasewater Railway
The Redruth and Chasewater Railway, otherwise called the Redruth and Chacewater Railway using modern spelling, was a very early industrial railway line in Cornwall, England, UK that opened in 1825 and closed in 1915...
, a narrow gauge route across the Cornish peninsula (planned in 1818, opened in 1825) used a significant incline to access the harbour at Portreath
Portreath
Portreath is a civil parish, village and fishing port on the north coast of Cornwall, United Kingdom. The village is situated approximately three miles northwest of Redruth....
, which like many in Cornwall
Cornwall
Cornwall is a unitary authority and ceremonial county of England, within the United Kingdom. It is bordered to the north and west by the Celtic Sea, to the south by the English Channel, and to the east by the county of Devon, over the River Tamar. Cornwall has a population of , and covers an area of...
sits in a steep valley.
Lancaster and Carlisle Railway
On the Lancaster and Carlisle RailwayLancaster and Carlisle Railway
The Lancaster and Carlisle Railway was a British railway company authorised on 6 June 1844 to build a line between Lancaster and Carlisle in North-West England...
(L&CR) of 1847 a deep cutting was cut at the Shap Summit. This cutting was cut through rock, about 0.5 mile (800 m) in length, and is between 50-60 feet (15-20 m) deep.
Docklands Light Railway
The entrance to the tunnel from the original London and Blackwall railway viaduct to the tunnel to BankBank and Monument stations
Bank and Monument are interlinked London Underground and Docklands Light Railway stations that form a public transport complex spanning the length of King William Street in the City of London. Bank station, named after the Bank of England, opened in 1900 and is served by the Central, Northern and...
has the steepest gradient on any British railway at 1 in 17 (5.88%). A zig zag stripe has been welded to the rail surface to allow trains to gain a satisfactory grip, and prevent slipping.
See also
- Funicular railway
- Grade (slope)
- Lickey InclineLickey InclineThe Lickey Incline is the steepest sustained main-line railway incline in Great Britain and is situated south of Birmingham, in England. The climb is a gradient of 1-in-37.7 for a continuous distance of two miles ....
- Mountain railwayMountain railwayA mountain railway is a railway that ascends and descends a mountain slope that has a steep grade. Such railways can use a number of different technologies to overcome the steepness of the grade...
- Rack railwayRack railwayA rack-and-pinion railway is a railway with a toothed rack rail, usually between the running rails. The trains are fitted with one or more cog wheels or pinions that mesh with this rack rail...
- Ruling gradientRuling gradientThe term "ruling grade" is usually used as a synonym for "steepest climb" between two points on a railroad. But if the steepest climb is, say, a quarter-mile of 2% upgrade preceded and followed by 1.5% grade the "ruling grade" can only be defined arbitrarily....
- SlopeSlopeIn mathematics, the slope or gradient of a line describes its steepness, incline, or grade. A higher slope value indicates a steeper incline....