This document discusses various aspects of railway track design and maintenance. It covers topics like alignment surveys, track gauges, stresses in tracks, rail selection, wear testing, corrugation and creep of rails, rail joints, welding of rails, and types of rail sections. Permanent way requirements include uniform gauge, proper rail leveling, strength against lateral forces, well-designed curves and gradients, minimum tractive resistance, and facilities for drainage and repairs. Coning of wheels is described as well as different rail gauges used in India like broad, meter and narrow gauge. Rail functions and requirements for an ideal section are also outlined.

1. UNIT 02
PART 01
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2.  Alignment survey
 Requirement
 Gauges
 Track section
 Coning of wheels
 Stresses in railway track
 Selection for rails
 Test on rail wear and defects
 Corrugation and creep of rails
 Rail joints
 Welding of panels
 Rails types and functions
PERMANAT WAY
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3. Permanent Way
The combination of rails, fitted on sleepers with the help of
fixtures and fastenings and resting on ballast and subgrade
is called the railway track or permanent way.
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4. REQUIREMENTS OF AN IDEAL PERMANENT WAY
The following are the principal requirements of an ideal
permanent way or of a good railway track :-
1. The gauge of the permanent way should be correct and uniform.
2. The rail should be in proper level in straight portion. Proper
amount of super elevation should be provided to the outer rail
above the inner rail on curved portion of the track.
3. The permanent way should be sufficiently strong against lateral
forces.
4. The curves, provided in the track, should be properly designed.
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5. 5. An even and uniform gradient should be provided through out
the length of the track.
6. The tractive resistance of the track should be minimum.
7. The design of the permanent way should be such that the load of
the train is uniformly distributed on both the rails so as to
prevent unequal settlement of the track.
8. All the components parts such as rails, sleepers, ballast, fixtures
and fastenings, etc. should satisfy the design requirements.
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6. 9. All the points and crossings, laid in the permanent way,
should be properly designed and carefully constructed.
10. It should be provided with proper drainage facilities so as to
drain off the rain water quickly away from the track.
11. It should be provided with safe and strong bridges coming in
the alignment of the track.
12. It should be so constructed that repairs and renewals of any
of its portion can be carried out without any difficulty.
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7. July 22, 2017 7

8. Track Cross-section
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9. Rail Gauges
1. Rail gauge is the distance between the inner sides of the two
parallel rails that make up a single railway line
2. Rail gauge is the distance between two rails of a railroad.
3. Sixty percent of the world's railways use a 4 feet 8½ inch (1435
mm) gauge, which is known as standard gauge or international
gauge.
4. Rail gauges larger than standard gauge are called broad gauge,
and rail gauges smaller than standard are called narrow gauge.
5. A dual gauge railway has three or four rails positioned so that
trains of two different gauges can use it.
6. A place where different gauges meet is called a break of gauge.
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10. Types of Rail Gauges
The different gauges prevalent in India are of the following these types
• Broad gauge (1676 mm)
• Metre gauge (1000 mm)
• Narrow gauge (762 mm & 610 mm).
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11. a. When the clear horizontal distance between the inner
faces of two parallel rails forming a track is 1676mm the
gauge is called Broad Gauge (B.G)
b. This gauge is also known as standard gauge of India and is
the broadest gauge of the world.
c. The Other countries using the Broad Gauge are Pakistan,
Bangladesh, Sri Lanka, Brazil, Argentine,etc.50% India’s
railway tracks have been laid to this gauge.
Broad Gauge
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12. Suitability
Broad gauge is suitable under the following Conditions
1. When sufficient funds are available for the railway project.
2. When the prospects of revenue are very bright.
3. This gauge is used for tracks in plain areas which are densely
populated.
4. For routes of maximum traffic, intensities and at places which
are centers of industry and commerce.
5. Suitable for high speed
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13. a. When the clear horizontal distance between the inner faces of two
parallel rails forming a track is 1000mm, the gauge is known as
Metre Gauge (M.G)
b. The other countries using Metre gauge are France, Switzerland,
Argentine, etc. 40% of India’s railway tracks have been laid to this
gauge.
Suitability
1. When the funds available for the railway project are inadequate.
2. When traffic efficiency is moderate.
3. When the prospects of revenue are not very bright.
4. This gauge is used for tracks in under-developed areas and in
interior areas
Meter Gauge
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14. a. When the clear horizontal distance between the inner faces of two
parallel rails forming a track is either 762mm or 610mm, the gauge is
known as Narrow gauge (N.G)
b. The other countries using narrow gauge are Britain, South Africa, etc.
10% of India’s railway tracks have been laid to this gauge.
Suitability
1. For low speed movement
2. When the construction of a track with wider gauge is prohibited due
to the provision of sharp curves, steep gradients, narrow bridges and
tunnels etc.
3. When the prospects of revenue are not very bright.
4. This gauge is used in hilly and very thinly populated areas.
Narrow Gauge
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15. CONING OF WHEELS
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16. Coning of Wheels
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17. 1. The flanges of wheel is never made flat, but they are in the
shape of cone with a slope of 1 in 20. (Sloping of the wheel
from the vertical axis)
2. The coning of wheels is mainly done to maintain the vehicle
in the central position with respect to the track.
3. It is done to maintain the vehicle in the central position with
respect to the track.
Advantages of coning
a. Reduce the wear and tear of wheel flanges and rails.
b. To provide possibility of lateral movement of the axle with its
wheels.
c. To prevent the slipping of wheels.
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18. RAILS
• General
Rail is similar to steel girders. These are placed
end to end to provide continuous and level
surface for the trains to move
On Indian Railways the standard lengths are
the following:
• Length = 12.80 meter for BG (say 13 m)
• Length = 11.89 meter for MG (say 12 m)
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19. Functions of Rail
1. To provide continuous and level surface for movement of train.
2. To provide a smooth pathway so that friction between rail and wheel
become less.
3. Serve as a lateral guide for the running of wheels.
4. Transferring the load into the sleeper.
5. To bear the stresses developed in the track due to temperature changes
and loading patterns.
6. To resist breaking forces caused due to stoppage of trains.
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20. Requirements of an ideal rail
The main requirements of an ideal rail section are as under
1. The section of the rail should be such that the load of eh wheels is
transferred to the sleepers without exceeding the permissible
stresses.
2. The section of the rail should be able to withstand the lateral forces
caused due to fast moving trains.
3. 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.
4. 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.
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21. 5. The web of the rail section should be such that it can safely bear the
vertical load without buckling.
6. The head of the rail should be sufficiently thick for adequate margin
of vertical wear.
7. 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.
8. The section of the rails should be such that the ends of two adjacent
rails can be efficiently jointed with a pair of fish plates.
9. The surfaces for rail table and gauge face should be sufficiently hard
to resist the wear.
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22. Types of rail sections
1. Double headed rails
2. Bull headed rails
3. Flat footed rails
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23. Double headed rails
a. These were the rails which were
used in the beginning, which were
double headed and consisting of a
dumb-bell section.
b. The idea behind using these rails
was that when the head was worn
out in course of time, the rail can
be inverted and reused.
c. But as time passed indentations
were formed in the lower table due
to which smooth running over the
surface at the top was impossible.
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24. Bull headed rails
• In this type of rail the head was made a little thicker and stronger
than the lower part by adding more metal to it, so that it can
withstand the stresses
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25. Flat footed rails
a. These rails are also called as vignole's rails.
b. Initially the flat footed rails were fixed to the sleepers directly and
no chairs and keys were required.
c. Later on due to heavy train loads problems arise which lead to steel
bearing plates between the sleeper and the rail. at rail joints and
other important places these are the rails which are most
commonly used in India.
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26. Rail Joints
a. Supported Rail Joint
b. Suspended Rail Joint
c. Bridge Joint
d. Base Joint
e. Welded Rail Joint
f. Staggered or Broken Joint
g. Square or Even Joint
h. Compromise Joint
i. Insulated Joint
j. Expansion Joint

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28. Insulated Joint

29. July 22, 2017 29
Expansion Joint

30. Creep of Rails
Creep is defined as the longitudinal movement of the rail with
respect to the sleepers.

31. Theories of creep
1. Wave action or wave
theory:
Wave motion is set up
by moving loads of
wheels.
The vertical reverse curve
ABC is formed in the rail
ahead of wheels, resulting
from the rail deflection
under the load.

32. ✓ Backward thrust on driving wheels of locomotive of train push the
rail off track backward.
✓ Mean while other wheel of locomotive and vehicles push the rail in
the direction of travel.
✓ Since drag effect is more as explained in Wave Action Theory
resultant creep of rails in forward direction.
Percussion Theory
This theory states that the creep is due to impact of wheels at the
rail end ahead at joints. Hence as and when wheel leave the trailing
rail and strike the facing rail end at each joint it pushes the rail in
forward direction resulting in creep
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Drag (or) Dragging theory

33. Factors effecting the magnitude & direction of creep.
• Alignment of track: Creep is more on curves than on tangent
tracks.
• Grade of track: More in case of steep curves, particularly
while train moving downward with heavy loads.
• Type of rails: older rail have more tendency than new one.
• Direction of heaviest traffic: In heavier load moving
direction occurs more creep.

34. Effects of creep
• Most serious effect of creep is being buckling of track.
• Sleepers move out of square and out of position, affects the gauge and
alignment of track. As sleepers move surface is disturbed results
uncomfortable riding.
• When joints are opened out beyond the permissible stress in bolts and fish
plates tendency to occurrence of failure in them.
• Its difficult to fix the removed rail at proper position during repair works
since the time gap becomes too short or too long due to creep.
• Smashing of fish plates, bolts, bending of bars, kinks at joints of rails and
forging of ballast ahead, common effects of creep.

35. Contd..
• Points and crossings get distorted, its too difficult to set them to
correct gauge and alignment. Movement of switches is made
difficult and interlocking is thrown out of gear.

36. Remedies of creep
1. Pulling back the rails
✓ pull back the rail to its original position. By means of crow bars and
hooks provided through the fish bolts wholes of rails
✓ By considering the position of joints relative to sleepers and both
rails should be in respective position.
2. Provision of anchors :
✓ By use of anchors and sufficient crib ballast.
✓ For creep 7.5 cm-15 cm 4 anchors per rail
✓ For creep 22.5 to 25 cm 6 anchors.
3. Use of steel sleepers:
✓ Sleepers should be made up of good material with proper fitting.
Sleepers should provide good grip with ballast to resist the
movement of sleepers. Increase in no. of sleepers.

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Provision of Anchors

38. Rail Wear
• Due to the passage of moving loads and friction between the rail
and the wheel, the rail head gets worn out is known as wear
Causes
• The impact of moving loads,
• The effect of the forces of acceleration, deceleration, and braking
of wheels
• Abrasion due to rail–wheel interaction
• The effects of weather conditions such as changes in
temperature, snow, and rains, the presence of materials.
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39. Type of Wear on Rails
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On the basis position of wear
1) on top of the rail head (vertical wear)
2) on the sides of the rail head (lateral wear)
3) on the ends of the rail (battering of rail ends)
On the basis of location
1) On sharp curves
2) On gradients
3) On approach to stations