Ebraheem Abdulrahman Alaman
Civil and Environmental Department, College of Engineering, Majmaah University, Kingdom of Saudi Arabia
On this report the history of railways and how it is beginning, the investigation and survey to create a new line and suitable earth depending on the level and configuration , the earthwork has two types cutting or embankment, important parts for railways they are rails and sleepers which carry the load an transfer it to the earth they are consistent from different material, G1 rails and sleepers are connected together each one has its function, Requirements, and types . G2 G3
History of railways. 4
Railways survey. 5
reasons for creating a new railway line:G4 5G5 G6
Factors influencing the proposed route: 5
Usual forms of cross-sections: 6
Features of railroad bed level: 6
Functions of Rail: 7
Requirements of an ideal rail: 7G7
Types of rail sections. 8
Functions of Sleepers: 9G8
Requirements of a good Sleeper: 9G9
Types of Sleepers: 10G10
Railways in KSA. 10
Figure 1 the first railway in IndiaG11 ….. 4
Figure 2 Rails. 7
Figure 3Type of rails section. 8
Figure 4 sleepers. 9
Table 1 standard width of formation. 6
The railway or rail line is called a rail line, made up of a parallel slab of steel bars installed on transverse elements called beams, placed over a well-grounded layer of plastic, in addition to its basic components such as station buildings, Electric equipment, change-direction equipment, and moving and mobile tools necessary for the operation and safety of trainsG12
Railways were known in G13 1804, in this year the start of a change in transport for trading and travel, until now the development increaseG14 , about the capacity and the speed by using a different type of energy and material.G15
Railways is consist of several components and each one has its function and purpose , in this report the survey of a new railway and construction why we created , reasons and types of survey , earthwork for railways its depends on the topography and G16 train level , rails and sleepers they are the route of train their function and Requirements and types , railways in KSA started since 1900 and connect Damascus to Medina , from this year the history begins to reach high development until this days .G17
History of railways
the history of railways is closely linked The first railway line in India was opened in 1853. The first train, consisting of one steam engine and four coaches, made its maiden trip on 16 April 1853, when it traversed a 21-mile stretch between Bombay (now Mumbai) and Thane in 1.25 hours, A British engineer, Robert Maitland Brereton, was responsible for the expansion of the railways from 1857 onwards. The Allahabad-Jabalpur branch line of the East Indian Railway had been opened in June 1867 , In 1951 the systems were nationalised as one unit, the Indian Railways, becoming one of the largest networks in the world , create basic change in the world , today the lengths World Railways Network reach 1.3 m km , maybe the speed reach to 320 kmh recently . G18
Figure 1 the first railway in India G19
The construction of a new railway line is a capital-intensive project and each kilometer of a new railway line costs in the range of G20 Rs 6 to 10 million depending upon the topography of the area, the standard of construction, and such other features. It is, therefore, natural that a lot of thought be given when making a final decision as to whether a new railway line is at all necessary or not.G21
reasons for creating a new railway G22 line : G23
1. Strategic consideration: Sometimes it becomes essential to join two points by a railway line for strategic purposes so that in case of emergency, the army can be transferred from one point to the other.
2. Linking of trade centersG24 : Two trade centersG25 may not be linked up by a railway line. In such cases, a new railway line is proposed between two such trade centersG26 .G27 G28 G29
3. Connecting port with the interior of the country: A port is sometimes not connected with the interior of the country. In such cases, it becomes essential to have a new railway line joining the port and the trade centersG30 of the interior of the country.G31
Factors influencing the proposed route:
– Cost: Should be minimum, Is composed of ( capital cost of the project + maintenance cost + renewal expenditure + working expenses), The route should be so selected as to bring the sum of all these costs to a minimum.
– Safety: The available passenger and goods traffic should be transported safely, Route should be so laid as to have minimum chances of train accidents
– Speed: Route should be so selected as to have the reasonable speed of trains.G32
In order to have a proper and satisfactory new route, various surveys are carried out:
1- Reconnaissance Survey 2- Preliminary Survey 3- Location Survey
1- Reconnaissance Survey: It is the first engineering survey, It is carried out in territory which has not been previously surveyed for the purpose of laying a new railway line. The main objects are as follows: To obtain a general knowledge of theG33 whole territory, and, To obtain information regarding the salient features of the territory.
2- Preliminary Survey: To conduct the survey work along the alternative routes found out by reconnaissance survey and, to determine with greater accuracy the cost of the railway line along these alternative routes.
3- 3. Location Survey: To carry out the detailed survey along the route which has been found and fixed as the most economical route from the data of the preliminary survey, It establishes the center-line of the actual track to be laid. G34 , As soon as the location survey is completed, the construction work is started.G35
The formation may be in an embankment or a cutting depending upon the rail level and general contour of the area. A formation in an embankment is normally preferred from the point of view of good drainage. The height of the embankment also depends on the high flood level of the area and a reasonable freeboard is provided above this level
Table 1 standard width of formation
Usual forms of cross-sections:
1- The naturally occurring soil is known as the subgrade and when it is prepared to receive the ballast and track, it is called the formation.
2- When the formation is raised on the bank of earth, it is called an embankment. G36
– When it is made after cutting the ground below ground level, it is called in cutting.
– In case of cutting, the line is laid below ground level and hence, the required portion is to be excavated.
Features of railroad bed level:
When the formation is to be made on embankment or cutting, various features should
be carefully considered.
1. The width of formation:G37 G38
The width of formation will depend on:
– the number of tracks,
– a gauge of tracks, G39
– center to G40 center distance between the tracks,G41 G42 G43
– Width of ballast layer
– The width of trenches to drain off the water, if necessary.G44 G45 G46
– The width of formation is normally kept sloping from the center for drainage purposes.G47 G48
2. Slopes of sides:
– The stability of the earthwork depends mainly on two factors, namely, cohesion and friction.
– For temporary stability, cohesion is useful and reliable,
-But permanent stability is achieved only by friction which keeps the slopes at the natural angle of repose of the material.
– The slopes to be provided to the sides of the formation should be slightly flatter than the angle of repose of the material.
– The slopes in cuttings vary from nearly vertical to 1.5 to 1 or steeper.
– The accumulation of water reduces the friction in all sorts of soils.
– In case of embankments, the rainwater is easily drained off. But in case of cuttings, drains are to be provided.
– The side drains are constructed along the track at a depth of about 1200 mm from the rail level.
– The size of drains will depend on the quantity of water to be drained.
– Sometimes, pipes of stoneware or concrete are laid in a trench with open or half open joints and covered with porous material.
Rails are the members of the track laid in two parallel lines to provide an unchanging, continuous, and level surface for the movement of trains. To be able to withstand stresses, they are made of high-carbon steel.
Figure 2 Rails
Functions of Rail:
– To provide a continuous and level surface for movement of the train.G49 G50
– To provide a smooth pathway so that friction between rail and wheel become less.
– Serve as a lateral guide for the running of wheels.
– Transferring the load into the sleeper.
– To bear the stresses developed in the track due to temperature changes and loading patterns.
– To resist breaking forces caused due to stoppage of trains.
Requirements of an ideal rail :
The main requirements of an ideal rail section are as under:
– The section of the rail should be such that the load of eh wheels is transferred to the sleepers without exceeding the permissible stresses.
– The section of the rail should be able to withstand the lateral forces caused due to fast-moving trains.G51
– The underside of the head and top of the foot of the rail section should be of such a slope that the fishplates fit snugly.
– The center of gravity of the rail section should preferably coincide the center of the height of the rail so that maximum tensile and compressive stresses are nearly equal.
– The web of the rail section should be such that it can safely bear the vertical load without buckling.
– The head of the rail should be sufficiently thick for an adequate margin of vertical wear.G52
– The foot of rail should provide sufficient bearing area on the underlying sleepers so that the compressive stresses on the timber sleeper remain within permissible limits.
Types of rail sections
1. Double-headed railsG53
2. Bullheaded rails
3. Flat footed rails.
Figure 3Type of rails section
Length of rails :
The most common length for BG rails is 13m (42’8”), although double-length rails (26m, 85’4”) are seen in some places, MG rails are usually 12m (39’4”) in length, NG rails vary, but the commonest length is 9m (29’6”).
Factors governing length of rails:-
– Manufacturing cost
– Transportation facility
– Lifting and handling operation
Welding of rails Purpose of welding To increase the length of the rails, To to repairG54 the worn out or damaged rails, To build up worn out points and rails on the sharp curves
Sleepers are the transverse ties that are laid to support the rails. They have an important role in the track as they transmit the wheel load from the rails to the ballast.
Figure 4 sleepers
Functions of Sleepers :
– To hold the rails t proper gauge in all situations. i.e. exact gauge along straights and flat curves, slightly loose on sharp curves and slightly tight in diamond crossings.
– To support the rails firmly and evenly throughout.
– To distribute the load transmitted through rails over the large area of ballast underneath or to the bridge G55 girders as the case may be.
– To hold the rails to the proper level in turnouts and crossovers, and at 1 in 20 inward slopes along straight tracks. G56 G57
– To provide an elastic medium between the rails and ballast and also to absorb the vibrations caused due to moving axle loads. G58
– To maintain proper alignment of the track. On curves, proper cant is provided by raising the outer rail and tamping he required a quantity of ballast below G59 G60 the rails.G61 G62
Requirements of a good Sleeper :
A good sleeper should meet the following requirements
– The initial cost and the maintenance cost of the sleepers should be low.
– The fittings required for fixing the rails on to the sleepers should be simple which can be easily adjusted during the maintenance.G63
– The crushing strength of the sleepers should be more with moderate weight.
– They should be able to maintain a perfect alignment, gauge, and levels of the rails and should afford efficient adjustment and maintenance.G64
– They should provide sufficient bearing area to hold the rail seats and for the ballast to be supported on, to resist the crushing due to movement of heavy axle loads.
– They should be capable to resist the shocks and vibrations caused due to fast moving vehicles at high speeds.
Types of Sleepers :
1- Sleepers based on the materials :
– Timber sleepers
– Steel sleepers
– Cast iron sleepers
– R.C.C sleepers
– Pre-stressed concrete sleepers.
2- Sleepers depending on the location :
– Longitudinal sleepers
These are earlier form of sleepers which are not in use nowadays, It consists of slabs or pieces of timber placed parallel to the rails, To maintain the correct gauge cross pieces were provided, These sleepers were costly, Noise created by the track is considerable
– Transverse sleepers
Also knows as cross sleepers, Placed at right angles under the rails, Eliminated the inconvenience of longitudinal sleepers.
Railways in KSA
The first railway in the Arabian peninsula was the 1050mm gauge Hejaz Railway from Damascus to Medina. Construction started in 1900, and the line reached Al Madinah (Medina) in 1908. It was proposed to continue the line to Makkah (Mecca), but this section was never constructed. Ostensibly a line to carry pilgrims on the Hajj, commentators have seen its real purpose as a political tool to bring the Hejaz region more closely within the Ottoman fold. Whatever the facts, the southern section of the railway was largely destroyed during the First World War (not least owing to the actions of Arab tribesmen led by T E Lawrence – better known as Lawrence of Arabia). The line south of what was to become the Jordanian border never reopened. A few derelict sections of track remain; stations at Madinah and Mada’in Saleh are preservedG65 as museums, each having some locomotives and rolling stock from the original railway.
The country remained without railways until 1951, when a 15km standard (1435mm) gauge line opened between the port of Dammam and warehouses at Dhahran. This was later extended to Riyadh, a distance of 450km. In 1985, another line was opened on a longer but more easily graded route between Riyadh and Al Hofuf, from where it paralleled the existing line to Dammam, a total distance of 556km. This line is used exclusively for freight services, high-quality passenger services continue to operate on the original route.G66
Ambitious projects for major new railways were put in hand in the early part of the 21st century. The 1400km North-South Railway from Al G67 Jalamid in the north of the country to Ras Al G68 Khair on the Gulf coast opened in 2012. Passenger services commenced in 2016. Various extensions to this line are under construction, including one which will link to the existing network at Riyadh. The G69 Haramain High-Speed Line is under construction between Makkah and Madinah, serving Jeddah, Jeddah Airport, and King Abdullah Economic City. Studies are on hand for the G70 G71 G72 Landbridge, a 945km railway from Jeddah to Riyadh, for a high-speedG73 line between Riyadh and Dammam, and for various other long-term projects. International links are proposed with Jordan, Kuwait, Qatar and the United Arab Emirates.G74 G75 G76 G77 G78 G79
Saudi Arabia starts a new vision to be a great G80 nation, the railways will be an important part and economic of transportG81 . However, the survey should provide Strategic consideration and Linking of trade centers , survey should consider the speed, safety, and cost G82 , to have a proper and satisfactory new route, various surveys are carried out: Reconnaissance Survey, Preliminary Survey and Location Survey, train level should be selected by studies of topographic, soils and a point of good drainage, in earth work preferred embankment from the point of view of good drainage , the rails and sleepers they should select from a good material and look for a good type to suitability the climate and loading , rails should provide a smooth pathway, resist breaking forces caused due to stoppage of trains and provide continuous and level surface for movement of train , sleepers should hold the rails t proper gauge in all situations, provide and elastic medium between the rails and ballast and absorb the vibrations caused due to moving axle loads. G83 G84 G85
This report has identified five topics of railways such as survey depend on uses of the train by some steps Reconnaissance G86 Survey, Preliminary Survey, Location Survey and more. earthwork is the formation may be in an embankment or a cutting depending upon the rail level and general contour of the area, should
be carefully considered various features as Width of formation, sloped sides and drains , rails G87 are the members of the track To provide continuous and level surface for movement of train rails has types by sections Double headed rails , Bullheaded rails and Flat-footed rails, increase the length of the rails by welding . G88 However sleepers the transverse load andG89 laid to support the rails. They are important in the track to transmit the wheel load from the rails to the ballast, they are under the rails Placed at right angles, they depending on the material and location . on this report a small information there is more about railways the load the select depend climate soils selection the stations and more, this report we should improve it about the tunnel, bridges, equipment, stations, and platforms, the new modern railways, the electric rails are the futures G90 and magnetic railways they are developed and will be in the future .
– SATISH G91 CHANDRA, M.M.AGRWAL, RAILWAY ENGINEERINGG92 , Published by Oxford University Press.G93 G94
– Clifford F. Bonnett, Practical Railway Engineering (2nd Edition), published by Imperial College Press. G95 G96
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