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Civil Engineering Railway Engineering Lectures| Lecture Notes|Traffic and Highway

Engineering Class Notes

What is Rails Definition and Types of Rails \| Double Headed Rails, Bull Headed and Flat Footed Rails (pdf )
Definition of Rails A rail is a steel bar extending horizontally between supports which is used as a track for rail road, cars or other vehicles. Types of Rails Rails can be divided in three types Double Headed Rails Bull Headed Rails Flat Footed Rails 1. Double Headed Rails These rails indicate the early stage of development. It essentially consists of three parts, Upper Table Web Lower Table Both the upper and lower tables were identical and they were introduced with the hope of double doubling the life of rails. When the upper table is worn out then the rails can be placed upside down reversed on the chair and so the lower table can be brought into use. But this idea soon turned out to b wrong because due to continuous contract of lower table with the chair made the surface of lower table rough and hence the smooth running of the train was impossible. Therefore, this type of rail is practically out of use. Nowadays, these rails vary in lengths from 20 – 24. A 100 lb double headed rail is shown in the figure.

What is Rails Definition and Types of Rails | Double Headed Rails, Bull Headed and Flat Footed Rails (pdf )

Definition of Rails

A rail is a steel bar extending horizontally between supports which is used as a track for rail road, cars or other vehicles.

Types of Rails

Rails can be divided in three types

Double Headed Rails
Bull Headed Rails
Flat Footed Rails

1. Double Headed Rails

These rails indicate the early stage of development. It essentially consists of three parts,

Upper Table
Web
Lower Table

Both the upper and lower tables were identical and they were introduced with the hope of double doubling the life of rails. When the upper table is worn out then the rails can be placed upside down reversed on the chair and so the lower table can be brought into use. But this idea soon turned out to b wrong because due to continuous contract of lower table with the chair made the surface of lower table rough and hence the smooth running of the train was impossible. Therefore, this type of rail is practically out of use. Nowadays, these rails vary in lengths from 20 – 24. A 100 lb double headed rail is shown in the figure.

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2. Bull Headed Rails This type of rail also consists of three parts, The Head The Web The Foot These rails were made of steel. The head is of larger size than foot and the foot is designed only to hold up properly the wooden keys with which rails are secured. Thus, the foot is designed only to furnish necessary strength and stiffness to rails. Two cast iron chairs are required per each sleeper when these rails are adopted. Their weight ranges from 85lb to 95lb and their length is up to 60 ft.

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2. Bull Headed Rails

This type of rail also consists of three parts,

The Head
The Web
The Foot

These rails were made of steel. The head is of larger size than foot and the foot is designed only to hold up properly the wooden keys with which rails are secured. Thus, the foot is designed only to furnish necessary strength and stiffness to rails. Two cast iron chairs are required per each sleeper when these rails are adopted. Their weight ranges from 85lb to 95lb and their length is up to 60 ft.

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3. Flat Footed Rails These rails were first of all invented by Charles Vignoles in 1836 and hence these rails are also called vignols rails. It consist of three parts The Head The Web The Foot The foot is spread out to form a base. This form of rail has become so much popular that about 90% of railway tracks in the world are laid with this form of rails.

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Flat footed rails has the following advantages They do not need any chair and can be directly spiked or keyed to the sleepers. Thus they are economical. They are much stiffer both vertically and laterally. The lateral stiffness is important for curves. They are less liable to develop kinks and maintain a more regular top surface than bull headed rails. They are cheaper than bull headed rails. The loads from wheels of trains are distributed over large number of sleepers and hence larger area which results in greater track stability, longer life of rails and sleepers, reduced maintenance, costs, less rail failure and few interruptions to traffic. Wear of Rails The separation or cutting of rail due to friction and abnormal heavy load is called wear. There are three types of wears of rail Read More Wear of Rails on top OR Head of Rail Wear at the End of Rails Wear at the side of head of Rails Methods for Reducing Wear of Rails The following methods are adopted for reducing wear of rails. Read More Use of Special Alloy Steel Good Maintenance of Track Reduction of Expansion Gap Exchange of Inner and Outer Rails on Curves Use of Lubricating Oil Coning of Wheels The rim or flanges of the wheels are never made flat but they are in the shape of a cone with a slope of about 1 to 20. This is known as coning of wheels. Read More

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Flat footed rails has the following advantages

They do not need any chair and can be directly spiked or keyed to the sleepers. Thus they are economical.
They are much stiffer both vertically and laterally. The lateral stiffness is important for curves.
They are less liable to develop kinks and maintain a more regular top surface than bull headed rails.
They are cheaper than bull headed rails.
The loads from wheels of trains are distributed over large number of sleepers and hence larger area which results in greater track stability, longer life of rails and sleepers, reduced maintenance, costs, less rail failure and few interruptions to traffic.

Wear of Rails

The separation or cutting of rail due to friction and abnormal heavy load is called wear. There are three types of wears of rail Read More

Wear of Rails on top OR Head of Rail
Wear at the End of Rails
Wear at the side of head of Rails

Methods for Reducing Wear of Rails

The following methods are adopted for reducing wear of rails. Read More

Use of Special Alloy Steel
Good Maintenance of Track
Reduction of Expansion Gap
Exchange of Inner and Outer Rails on Curves
Use of Lubricating Oil

Coning of Wheels

The rim or flanges of the wheels are never made flat but they are in the shape of a cone with a slope of about 1 to 20. This is known as coning of wheels. Read More

What is Creep in Rail Railway Engineering Notes ( pdf )
What is Creep in Rail Creep in rail is defined as the longitudinal movement of the rails in the track in the direction of motion of locomotives. Creep is common to all railways and its value varies from almost nothing to about 6 inches or 16cm. Causes of Creep The causes of creep in rail can be broadly classified into two categories Major Causes o Creep Minor Causes of Creep Major Causes of Creep Major causes of creep also known as principal causes of creep. Follows are the major causes of creep in rail 1. Creep may be developed due to forces that come into operation when the train is starting or stopping by application of brakes. Increase of starting the wheels pushes the rail backward and hence the direction of creep is in backward direction

What is Creep in Rail Railway Engineering Notes ( pdf )

What is Creep in Rail

Creep in rail is defined as the longitudinal movement of the rails in the track in the direction of motion of locomotives. Creep is common to all railways and its value varies from almost nothing to about 6 inches or 16cm.

Causes of Creep

The causes of creep in rail can be broadly classified into two categories

Major Causes o Creep
Minor Causes of Creep

Major Causes of Creep

Major causes of creep also known as principal causes of creep. Follows are the major causes of creep in rail

1. Creep may be developed due to forces that come into operation when the train is starting or stopping by application of brakes. Increase of starting the wheels pushes the rail backward and hence the direction of creep is in backward direction

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When brakes are applied then the wheels of the vehicles push the rails in forward direction and hence the creep is in forward direction.

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2. Creep is also developed due to wave motions. When the wheels of the vehicles strikes the crests, creep is developed.

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3. Another reason creep develops because of unequal expansion and contraction owing to change in temperature. Minor Causes Creep Some of the minor causes of creep in rail are below: Rails not properly fixed to sleepers Bad drainage of ballast Bad quality of sleepers used Improper consolidation of formation bed Gauge fixed too tight or too slack Rails fixed too tight to carry the traffic Incorrect adjustment of super elevation on outer rails at curves Incorrect allowance for rails expansion Rail joints maintained in bad condition Magnitude and Direction of Creep Creep is not constant over a given period, it is not continue in one direction or at uniform rate. Both the rails of the track may creep in same direction, perhaps both the rails reverse the direction of creep or one rail creep in opposite direction to that of other. Read More Results and Consequences of Creep Following are some of the undesirable consequences of creep 1. The most serious effect of creep is the buckling of track in lateral directions. If unattended and not properly removed then it causes derailments which leads to accidents. Read More Correction of Creep\|Methods against Creep There are two methods used for the correction of creep. These are Pulling back Method Use of Creep Anchors / Anti Creepers Read More

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3. Another reason creep develops because of unequal expansion and contraction owing to change in temperature.

Minor Causes Creep

Some of the minor causes of creep in rail are below:

Rails not properly fixed to sleepers
Bad drainage of ballast
Bad quality of sleepers used
Improper consolidation of formation bed
Gauge fixed too tight or too slack
Rails fixed too tight to carry the traffic
Incorrect adjustment of super elevation on outer rails at curves
Incorrect allowance for rails expansion
Rail joints maintained in bad condition

Magnitude and Direction of Creep

Creep is not constant over a given period, it is not continue in one direction or at uniform rate. Both the rails of the track may creep in same direction, perhaps both the rails reverse the direction of creep or one rail creep in opposite direction to that of other. Read More

Results and Consequences of Creep

Following are some of the undesirable consequences of creep

1. The most serious effect of creep is the buckling of track in lateral directions. If unattended and not properly removed then it causes derailments which leads to accidents. Read More

Correction of Creep|Methods against Creep

There are two methods used for the correction of creep. These are

Pulling back Method
Use of Creep Anchors / Anti Creepers Read More

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Coning of Wheels Railway Engineering Notes ( pdf ) Coning of Wheel The rim or flanges of the wheels are never made flat but they are in the shape of a cone with a slope of about 1 to 20. This is known as coning of wheels. The coning of wheels is manly done to maintain the vehicle in the central position with respect to the track. When the vehicle is moving on leveled track then the flanges of wheels have equal circumference. But when the vehicle is moving along a curved path then in this case the outer wheel has to cover a greater distance then that of inner wheel. Also as the vehicle has a tendency to move sideways towards the outer rail, the circumferences of the flanges of the inner wheel and this will help the outer wheel to cover a longer distance than the inner wheel. In this ways smooth riding is produced by means of coning of wheels. Coning Wheels Disadvantages Coning wheels has the following disadvantages: In order to minimize the above below disadvantages the tilting of rails is done. i.e. the rails are not laid flat but tilted inwards by using inclined base plates sloped at 1 in 20 which is also the slope of coned surface of wheels. The pressure of the horizontal component near the inner edge of the rail has a tendency to wear the rail quickly. The horizontal components tend to turn the rail outwardly and hence the gauge is widened sometimes. If no base plates are provided, sleepers under the outer edge of the rails are damaged. In order to minimize the above mentioned disadvantages the tilting of rails is done. i.e. the rails are not laid flat but tilted inwards by using inclined base plates sloped at 1 in 20 which is also the slope of coned surface of wheels. Advantages of Tilting of Rails It maintains the gauge properly. The wear at the head of rail is uniform. It increases the life of sleepers and the rails.

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Coning of Wheels Railway Engineering Notes ( pdf )

Coning of Wheel

The rim or flanges of the wheels are never made flat but they are in the shape of a cone with a slope of about 1 to 20. This is known as coning of wheels. The coning of wheels is manly done to maintain the vehicle in the central position with respect to the track. When the vehicle is moving on leveled track then the flanges of wheels have equal circumference.

But when the vehicle is moving along a curved path then in this case the outer wheel has to cover a greater distance then that of inner wheel. Also as the vehicle has a tendency to move sideways towards the outer rail, the circumferences of the flanges of the inner wheel and this will help the outer wheel to cover a longer distance than the inner wheel. In this ways smooth riding is produced by means of coning of wheels.

Coning Wheels Disadvantages

Coning wheels has the following disadvantages:

In order to minimize the above below disadvantages the tilting of rails is done. i.e. the rails are not laid flat but tilted inwards by using inclined base plates sloped at 1 in 20 which is also the slope of coned surface of wheels.
The pressure of the horizontal component near the inner edge of the rail has a tendency to wear the rail quickly.
The horizontal components tend to turn the rail outwardly and hence the gauge is widened sometimes.
If no base plates are provided, sleepers under the outer edge of the rails are damaged.
In order to minimize the above mentioned disadvantages the tilting of rails is done. i.e. the rails are not laid flat but tilted inwards by using inclined base plates sloped at 1 in 20 which is also the slope of coned surface of wheels.

Advantages of Tilting of Rails

It maintains the gauge properly.
The wear at the head of rail is uniform.
It increases the life of sleepers and the rails.


Wear of Rails Transportation Engineering Notes ( pdf ) What is Wear of Rail The separation or cutting of rail due to friction and abnormal heavy load is called wear. There are three types of wears of rail 1. Wear of Rails on top OR Head of Rail The metal from the top of rail flows and forms projections which are known as burns. The causes of such types of wear are: Rails are worn out on top due to abrasion of the rolling wheels over them. The heavy wheel loads are concentrated on very small areas. Impact of heavy loads Corrosion of metal of rails Due to slipping action of wheels during starting and when brakes are applied to the moving trains, the metal of top of rail burns.

Wear of Rails Transportation Engineering Notes ( pdf )

What is Wear of Rail

The separation or cutting of rail due to friction and abnormal heavy load is called wear. There are three types of wears of rail

1. Wear of Rails on top OR Head of Rail

The metal from the top of rail flows and forms projections which are known as burns. The causes of such types of wear are:

Rails are worn out on top due to abrasion of the rolling wheels over them.
The heavy wheel loads are concentrated on very small areas.
Impact of heavy loads
Corrosion of metal of rails
Due to slipping action of wheels during starting and when brakes are applied to the moving trains, the metal of top of rail burns.

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2. Wear at the End of Rails This wear of rails takes place at the ends of rails and is found to be very much greater than the wear at the top of rails. At the expansion gap, the wheels of the vehicle have to take a jump and during this jump, they impart a blow is the ends of the rails. This blow is the main cause of wear of rails at ends. Due to successive blows, the ends of the rails are battered.

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2. Wear at the End of Rails

This wear of rails takes place at the ends of rails and is found to be very much greater than the wear at the top of rails. At the expansion gap, the wheels of the vehicle have to take a jump and during this jump, they impart a blow is the ends of the rails. This blow is the main cause of wear of rails at ends. Due to successive blows, the ends of the rails are battered.

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3. Wear at the side of head of Rails This is the most destructive type of wear and occurs on the rails laid on curves. The various causes of this type of wear are:

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Due to centrifugal force along the curvature, the grinding action of wheel flanges on the inner side of the head of the rails is caused. The vehicles do not bend to the shape of the curvature while moving over a curve. This results into the biting of the inner side of the head of outer rail by wheel flanges. The wear on the inner side of the head of inner rail is mainly due to the slipping action of wheel on curve. Outer wheels have to cover a longer distance than inner wheel as “pq” is greater than “rs”. But due to rigid connection between two wheels, they cover the same distance and hence then inner wheel slips over the inner rail, resulting in the wear of inner side of head of inner rail.

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Due to centrifugal force along the curvature, the grinding action of wheel flanges on the inner side of the head of the rails is caused.
The vehicles do not bend to the shape of the curvature while moving over a curve. This results into the biting of the inner side of the head of outer rail by wheel flanges.
The wear on the inner side of the head of inner rail is mainly due to the slipping action of wheel on curve. Outer wheels have to cover a longer distance than inner wheel as “pq” is greater than “rs”. But due to rigid connection between two wheels, they cover the same distance and hence then inner wheel slips over the inner rail, resulting in the wear of inner side of head of inner rail.

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Railway Survey \| Survey for New Railway Line ( pdf ) To construct anything haphazardly is not engineering. Prior to survey the available maps of proposed area are studied. This helps in fixing suitable alignment facilitate various surveys work. The various engineering surveys which are carried out for the choice of route of a new railway line can broadly be divided in to three categories. 1. Reconnaissance Survey 2. Preliminary Survey 3. Location Survey 1. Reconnaissance Survey A reconnaissance survey is the first engineering survey which is carried out in territory which has not been previously surveyed for the purpose of laying a new railway line. The main objects of reconnaissance survey are as follows: To obtain a general knowledge of the whole territory and To obtain information regarding the salient feature of the territory. Importance of Reconnaissance Survey By reconnaissance survey, a number of possible alternative routes between two points can be worked out. This information becomes useful at a later stage in the selection of best possible route between two points. The successful conduct of the reconnaissance survey entirely depends on the personal qualities and abilities of engineers such as training and experience, capacity of observation and interpretation of the features of the territory etc. Reconnaissance Survey and Information Gathered The information are generally gathered in the following two categories Traffic Reconnaissance Survey Engineering Reconnaissance Survey Traffic Reconnaissance Survey This consists of collection of the information regarding the following: General character of the country and extent of cultivation Local industries and religious festivals The general conditions such as prosperity of people in the locality and density of population and its distribution The probable amount of traffic to be served by a new railway line The probable new traffic lines to be opened up to join large trade centers Nature and volume of exports and their destination and origin The amount of imports and centers of their distribution Possibilities of development of new industries and irrigation schemes as a result of new railway lines Engineering Reconnaissance Survey Engineering Reconnaissance Survey, the following information is collected Physical features of a country The surface formation of the ground Nature of soil Streams and rivers in the area especially those likely to be crossed by the track, their direction of flow, approximate width and depth Positions of hills and lakes Instruments Used in Reconnaissance Survey Aneroid Barometer Prismatic Compass Binocular telescope Pedometer 2. Preliminary Survey The object of preliminary survey is To conduct the survey work along the alternative routes (found out by reconnaissance survey) with the help of theodolite and leveling instruments To determine the greater accuracy the cost of railway line along these alternative routes involving cost of removing obstruction, construction of bridges etc To decide the most economical and efficient route Importance of Preliminary Survey The preliminary surveys decide the final route and recommend only one particular route in preference to other alternative routes. Thus, the preliminary survey should be carried out with greater precision as the alignment of final route depends on it. Works of Preliminary Survey The x-sections of all representative points along the route and feature of the country are marked. The cross sections are taken at 500ft interval normally. Similarly where the route crosses a river, the river is surveyed in detail for about one mile on either the upstream and downstream sides. The detail maps are prepared and the cost of different alternatives is calculated accurately to select the most economic routes. Instrument Used in Preliminary Survey Dumpy level Prismatic compass Tachometer Plane table Appropriate helping instruments 3. Location Survey It is the final survey used to locate the centre line of the railway line the main object of this survey is to carry out the detaile3d survey along the route which has been fixed as the most economical route from the data of preliminary survey. Importance of Location Survey The location survey established the center line of actual track to be laid and hence as soon as the location survey is completed, the construction work is started. Work of Location Survey The location survey is carried out in two stages Paper Location Field Location Paper Location The final route selected is put up on paper and details such as gradient, curves, contours etc are worked out. The long sections and formation levels are sorted out and working drawings are prepared for all small and large structures. Field Location The field location transfers the paper location to the ground to have a good profile as in paper location. It also gives the requirements of the construction engineer such as benchmarks, levels, measurements etc. The centre line pegs are driven at every 1000 ft or 300 m along the centre line of the track. Every change in direction, the beginning and end of a curve and the intersection of tangents are clearly marked. Sufficient benchmarks are established at a distance not more than ½ miles along the alignment to which levels can be referred and gradients can be transferred. The centre line and other pegs are surrounded by stone masonry or concrete pillars on which the changes and levels are marked. The centre lines of culverts, bridges, tunnels, stations buildings, yards, signal cabins etc should also be fixed. The construction work should also be possible after completion of location survey. Instruments Used in Location Survey Theodolite Precise Level Steel Tape

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Railway Survey | Survey for New Railway Line ( pdf )

To construct anything haphazardly is not engineering. Prior to survey the available maps of proposed area are studied. This helps in fixing suitable alignment facilitate various surveys work. The various engineering surveys which are carried out for the choice of route of a new railway line can broadly be divided in to three categories.

1. Reconnaissance Survey

2. Preliminary Survey

3. Location Survey

1. Reconnaissance Survey

A reconnaissance survey is the first engineering survey which is carried out in territory which has not been previously surveyed for the purpose of laying a new railway line. The main objects of reconnaissance survey are as follows:

To obtain a general knowledge of the whole territory and
To obtain information regarding the salient feature of the territory.

Importance of Reconnaissance Survey

By reconnaissance survey, a number of possible alternative routes between two points can be worked out. This information becomes useful at a later stage in the selection of best possible route between two points. The successful conduct of the reconnaissance survey entirely depends on the personal qualities and abilities of engineers such as training and experience, capacity of observation and interpretation of the features of the territory etc.

Reconnaissance Survey and Information Gathered

The information are generally gathered in the following two categories

Traffic Reconnaissance Survey
Engineering Reconnaissance Survey

Traffic Reconnaissance Survey

This consists of collection of the information regarding the following:

General character of the country and extent of cultivation
Local industries and religious festivals
The general conditions such as prosperity of people in the locality and density of population and its distribution
The probable amount of traffic to be served by a new railway line
The probable new traffic lines to be opened up to join large trade centers
Nature and volume of exports and their destination and origin
The amount of imports and centers of their distribution
Possibilities of development of new industries and irrigation schemes as a result of new railway lines

Engineering Reconnaissance Survey

Engineering Reconnaissance Survey, the following information is collected

Physical features of a country
The surface formation of the ground
Nature of soil
Streams and rivers in the area especially those likely to be crossed by the track, their direction of flow, approximate width and depth
Positions of hills and lakes

Instruments Used in Reconnaissance Survey

Aneroid Barometer
Prismatic Compass
Binocular telescope
Pedometer

2. Preliminary Survey

The object of preliminary survey is

To conduct the survey work along the alternative routes (found out by reconnaissance survey) with the help of theodolite and leveling instruments
To determine the greater accuracy the cost of railway line along these alternative routes involving cost of removing obstruction, construction of bridges etc
To decide the most economical and efficient route

Importance of Preliminary Survey

The preliminary surveys decide the final route and recommend only one particular route in preference to other alternative routes. Thus, the preliminary survey should be carried out with greater precision as the alignment of final route depends on it.

Works of Preliminary Survey

The x-sections of all representative points along the route and feature of the country are marked. The cross sections are taken at 500ft interval normally. Similarly where the route crosses a river, the river is surveyed in detail for about one mile on either the upstream and downstream sides. The detail maps are prepared and the cost of different alternatives is calculated accurately to select the most economic routes.

Instrument Used in Preliminary Survey

Dumpy level
Prismatic compass
Tachometer

Plane table
Appropriate helping instruments

3. Location Survey

It is the final survey used to locate the centre line of the railway line the main object of this survey is to carry out the detaile3d survey along the route which has been fixed as the most economical route from the data of preliminary survey.

Importance of Location Survey

The location survey established the center line of actual track to be laid and hence as soon as the location survey is completed, the construction work is started.

Work of Location Survey

The location survey is carried out in two stages

Paper Location
Field Location

Paper Location

The final route selected is put up on paper and details such as gradient, curves, contours etc are worked out. The long sections and formation levels are sorted out and working drawings are prepared for all small and large structures.

Field Location

The field location transfers the paper location to the ground to have a good profile as in paper location. It also gives the requirements of the construction engineer such as benchmarks, levels, measurements etc. The centre line pegs are driven at every 1000 ft or 300 m along the centre line of the track. Every change in direction, the beginning and end of a curve and the intersection of tangents are clearly marked. Sufficient benchmarks are established at a distance not more than ½ miles along the alignment to which levels can be referred and gradients can be transferred. The centre line and other pegs are surrounded by stone masonry or concrete pillars on which the changes and levels are marked. The centre lines of culverts, bridges, tunnels, stations buildings, yards, signal cabins etc should also be fixed. The construction work should also be possible after completion of location survey.

Instruments Used in Location Survey

Theodolite
Precise Level
Steel Tape

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Methods for Reducing Wear of Rails ( pdf ) The following methods are adopted for reducing wear of rails 1. Use of Special Alloy Steel At places where, wear of rail is considerable, special alloy steel rails are used. The cost of such rail is more but considerable reduction of wear of such rails justifies the extra cost. 2. Good Maintenance of Track The track should be carefully looked after and joints should be tightened if they become loose. A well maintained track would definitely result in less wear of rails. 3. Reduction of Expansion Gap If the expansion gap has increased beyond a certain limit, it should be reduced by packing the sleepers at the joints and tightening fish bolts. This will result in the reduction of wear of end of rails. 4. Exchange of Inner and Outer Rails on Curves Mostly on curves, where there is heavy wear at the top of head of inner rail and heavy wear of the side of head of outer rail then the top wear rail is exchanged with the side wear rail and thereby life of rail is increased. 5. Use of Lubricating Oil The wear of rails can also be reduced by applying lubricating oil on curves on the side of head of rails. The lubrication of rails can be carried out manually or by mechanical equipment attached to locomotive for rail.

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Methods for Reducing Wear of Rails ( pdf )

The following methods are adopted for reducing wear of rails

1. Use of Special Alloy Steel

At places where, wear of rail is considerable, special alloy steel rails are used. The cost of such rail is more but considerable reduction of wear of such rails justifies the extra cost.

2. Good Maintenance of Track

The track should be carefully looked after and joints should be tightened if they become loose. A well maintained track would definitely result in less wear of rails.

3. Reduction of Expansion Gap

If the expansion gap has increased beyond a certain limit, it should be reduced by packing the sleepers at the joints and tightening fish bolts. This will result in the reduction of wear of end of rails.

4. Exchange of Inner and Outer Rails on Curves

Mostly on curves, where there is heavy wear at the top of head of inner rail and heavy wear of the side of head of outer rail then the top wear rail is exchanged with the side wear rail and thereby life of rail is increased.

5. Use of Lubricating Oil

The wear of rails can also be reduced by applying lubricating oil on curves on the side of head of rails. The lubrication of rails can be carried out manually or by mechanical equipment attached to locomotive for rail.

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Magnitude and Direction of Creep Railway Engineering (pdf ) What is Creep Creep is not constant over a given period, it is not continue in one direction or at uniform rate. Both the rails of the track may creep in same direction, perhaps both the rails reverse the direction of creep or one rail creep in opposite direction to that of other. In other words, the direction and magnitude of creep cannot be predicted. Following are some of the items governing the direction and magnitude of creep 1. Alignment of Track Creep is found to be greater on curves than on straights. 2. Grade of Track Rails normally creep in the direction of downgrade through the creep in reverse direction i.e. upgrade is also possible. 3. Direction of Heavy Traffic If heavy or loaded vehicles run in one direction and the empty train move in opposite direction then the creep is founded to be in the direction of loaded trains. Results and Consequences of Creep Following are some of the undesirable consequences of creep The most serious effect of creep is the buckling of track in lateral directions. If unattended and not properly removed then it causes derailments which leads to accidents. Sleepers do not remain at fixed position and then gauges of the track are disturbed. The alignment and rail level is also disturbed. This causes bad running of trains. It becomes difficult to fix the rails with creep. It is found either too short or too long due to creep. The gaps are widened at some places while closer at some places. This causes undue stresses. The location of points and crossings is disturbed and it is difficult to keep correct gauge and the alignment. The interlocking mechanism is also disturbed due to creep in rails.

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Magnitude and Direction of Creep Railway Engineering (pdf )

What is Creep

Following are some of the items governing the direction and magnitude of creep

1. Alignment of Track

Creep is found to be greater on curves than on straights.

2. Grade of Track

Rails normally creep in the direction of downgrade through the creep in reverse direction i.e. upgrade is also possible.

3. Direction of Heavy Traffic

If heavy or loaded vehicles run in one direction and the empty train move in opposite direction then the creep is founded to be in the direction of loaded trains.

Results and Consequences of Creep

Following are some of the undesirable consequences of creep

The most serious effect of creep is the buckling of track in lateral directions. If unattended and not properly removed then it causes derailments which leads to accidents.
Sleepers do not remain at fixed position and then gauges of the track are disturbed. The alignment and rail level is also disturbed. This causes bad running of trains.
It becomes difficult to fix the rails with creep. It is found either too short or too long due to creep.
The gaps are widened at some places while closer at some places. This causes undue stresses.
The location of points and crossings is disturbed and it is difficult to keep correct gauge and the alignment.
The interlocking mechanism is also disturbed due to creep in rails.

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Reasons for New Railway Line Railway Engineering Notes Why New Railway Line A new railway line is required for the following purposes: Strategic Consideration. Sometimes it becomes essential to join two points by a railway line for strategic purposes so that incase of emergency, army can be transferred from one point to other quickly. Linking of Trade Centers. Two Trade centers are linked to each other by laying a new railway line for economic reasons. Connection of Port to Interior of Country. Port is an important component of nations’ economy. They are connected to the trade centers of the interior of the country by laying new railway lines. Shortening Existing Route. Sometimes an existing track of railway line is longer than a short track is to be laid to decrease the distance between two points. Laying of a Branch Line. Branch lines are laid from main lien to link certain cities with other parts of the country and to develop it. Factors Influencing the Proposed Railway Track The following factors should be taken into account while selecting a proposed railway line: Cost Safety Speed Cost The cost of laying the railway line should be minimum. The cost of the railway line is composed of capital cost of the project, the maintenance cost, the renewal expenditure and the working expenses. The different alternatives should be worked out and the one giving the minimum cost and fulfilling all other requirements should be selected. Safety The safe transportation of goods and passengers should be the top priority of a railway project. The new railway track should be so laid that there are minimum chances of accidents. The topography of the area should be thoroughly studied and the proposed route should pass from line having allowable gradient, less shock and in a straight line to avoid curves thus increasing the safety of passengers and goods. Speed The route should be selected in such a way to allow for reasonable speed of trains i.e. it should avoid steep gradients, upgrade curves etc, which tends to decrease the speed of train. The route should be in straight line. Least Distance The route of the railway track should select in such a manner to provide all the three parameters within least possible distance to decrease the time of travel.

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Reasons for New Railway Line Railway Engineering Notes

Why New Railway Line

A new railway line is required for the following purposes:

Strategic Consideration. Sometimes it becomes essential to join two points by a railway line for strategic purposes so that incase of emergency, army can be transferred from one point to other quickly.
Linking of Trade Centers. Two Trade centers are linked to each other by laying a new railway line for economic reasons.
Connection of Port to Interior of Country. Port is an important component of nations’ economy. They are connected to the trade centers of the interior of the country by laying new railway lines.
Shortening Existing Route. Sometimes an existing track of railway line is longer than a short track is to be laid to decrease the distance between two points.
Laying of a Branch Line. Branch lines are laid from main lien to link certain cities with other parts of the country and to develop it.

Factors Influencing the Proposed Railway Track

The following factors should be taken into account while selecting a proposed railway line:

Cost
Safety
Speed

Cost

The cost of laying the railway line should be minimum. The cost of the railway line is composed of capital cost of the project, the maintenance cost, the renewal expenditure and the working expenses. The different alternatives should be worked out and the one giving the minimum cost and fulfilling all other requirements should be selected.

Safety

The safe transportation of goods and passengers should be the top priority of a railway project. The new railway track should be so laid that there are minimum chances of accidents. The topography of the area should be thoroughly studied and the proposed route should pass from line having allowable gradient, less shock and in a straight line to avoid curves thus increasing the safety of passengers and goods.

Speed

The route should be selected in such a way to allow for reasonable speed of trains i.e. it should avoid steep gradients, upgrade curves etc, which tends to decrease the speed of train. The route should be in straight line.

Least Distance

The route of the railway track should select in such a manner to provide all the three parameters within least possible distance to decrease the time of travel.

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What is Ballast \| Railway Ballast \| Functions of Ballast ( pdf ) What is Ballast Ballast is the foundation of railway track and provide just below the sleepers. The loads from the wheels of trains ultimately come on the ballast through rails and sleepers. Functions of Ballast Some of the important functions of ballast are: To provide firm and level bed for the sleepers to rest on To allow for maintaining correct track level without disturbing the rail road bed To drain off the water quickly and to keep the sleepers in dry conditions To discourage the growth of vegetation To protect the surface of formation and to form an elastic bed To hold the sleepers in position during the passage of trains To transmit and distribute the loads from the sleepers to the formation To provide lateral stability to the track as a whole Requirements for Ideal Ballast The ideal material for ballast should fulfill the following requirements It should be possible to maintain the required depth of the material in order to distribute the load of passing train on the formation ground The material to be used for ballast should not be too rigid but it should be elastic in nature The material for ballast should be of such nature that it grips the sleepers in position and prevent their horizontal movement during passage of train It should not allow the rain water to accumulate but should be able to drain off the water immediately without percolating It should be strong enough a resistance to abrasion Materials for Ballast The following materials are used for ballast on the railway track. Broken Stone Gravel Cinders / Ashes Sand Kankar Moorum Brick Ballast Selected Earth Read More

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What is Ballast | Railway Ballast | Functions of Ballast ( pdf )

What is Ballast

Ballast is the foundation of railway track and provide just below the sleepers. The loads from the wheels of trains ultimately come on the ballast through rails and sleepers.

Functions of Ballast

Some of the important functions of ballast are:

To provide firm and level bed for the sleepers to rest on
To allow for maintaining correct track level without disturbing the rail road bed
To drain off the water quickly and to keep the sleepers in dry conditions
To discourage the growth of vegetation
To protect the surface of formation and to form an elastic bed
To hold the sleepers in position during the passage of trains
To transmit and distribute the loads from the sleepers to the formation
To provide lateral stability to the track as a whole

Requirements for Ideal Ballast

The ideal material for ballast should fulfill the following requirements

It should be possible to maintain the required depth of the material in order to distribute the load of passing train on the formation ground
The material to be used for ballast should not be too rigid but it should be elastic in nature
The material for ballast should be of such nature that it grips the sleepers in position and prevent their horizontal movement during passage of train
It should not allow the rain water to accumulate but should be able to drain off the water immediately without percolating
It should be strong enough a resistance to abrasion

Materials for Ballast

The following materials are used for ballast on the railway track.

Broken Stone
Gravel
Cinders / Ashes
Sand
Kankar
Moorum
Brick Ballast
Selected Earth Read More

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Materials for Railway Ballast on the Railway Track Materials for Ballast Railway Engineering Notes The following materials for Railway Ballast used on the railway track. 1. Broken Stone 2. Gravel 3. Cinders / Ashes 4. Sand 5. Kankar 6. Moorum 7. Brick Ballast 8. Selected Earth 1. Broken Stone Broken stone is one of the best materials for railway ballst to be used on the railway tracks. Almost all the important railway tracks are provided with broken stone. The stone to be used as railway ballast should be hard, tough nonporous and should not decompose when exposed to air and light. Igneous rocks like quartzite and granite forms the excellent ballast materials. When these are not available then lime stone and sand stone can also be used as good ballast material. Advantages of Broken Stone It holds the track in position It is good for heavy traffic It can serve high speeds equally well. Disadvantages of Broken Stone The main disadvantage is that it is expensive in its initial cost. 2. Gravel Gravel ranks next in its suitability for use as materials for ballast and is used in many countries of the world in very large quantities. Gravel consists of worn fragments of rocks occurring in natural deposits. Gravel or shingle may be obtained from river bed or it may be dug out from gravel pits. Advantages of Gravel It is cheaper in its cost as it has not to be broken as like stone ballast It has got excellent drainage properties, if properly cleaned Disadvantages of Gravel It easily rolls down under the vibrations and packing under the sleepers get tense The variation in size is considerable and hence requires screening before use Grovel as obtained from gravel pits, is full of earth and hence requires proper cleaning if proper drainage of the track is to be done. 3. Cinders Or Ashes The residue from the coal in locomotives or other furnaces is called cinder or ashes. It is one of the universal forms of ballast as it is a byproduct of all the railway which uses coal as a fuel. Advantages of Cinders or Ashes Handling of the material is not cumbersome this material can be handle easily Cost is very low and hence can also be used for sidings It has got fairly good drainage properties Large quantities of this material can be made available at short notice. In case of emergence such as caused by the destruction of portion of railway track during floods. This material proves to be very useful and is used in the formation repairing as well as for packing of track. Disadvantages of Cinders or Ashes It is highly corrosive and cannot be used where steel sleepers are fixed The foot of the rails get affected due to use of this type of material as ballast It is very soft and can easily be reduced to powder under vibrations and hence the track becomes very dusty. This is objectionable particularly in dry weather. 4. Sand Sand is another good materials for railway ballast , coarser sand is to be preferred to finer sand and the best sand is that which contains a quantity of fine gravel varying in size from 1/8 upwards. Advantages of Sand If the sand is free from earth and vegetation then it has good excellent properties to drain off water immediately It is cheaper if available in nearby locality It produces very silent track and hence are suitable for packing cast iron pot sleepers. Disadvantages of Sand It gets easily disturbed under vibrations and hence its maintenance is very difficult The sand can be easily washed off or blown away and hence requires frequent renewal. The sand particles may get into the moving parts of the vehicles and produces friction. This leads to heavy wear of vehicles 5. Kankar Kankar a lime agglomerate is found in many places in the form of nodules of varying sizes. Advantages of Kankar Kankar is suitable Materials for ballast when other good material for ballast is not available or if available uneconomically. Kankar is good for light traffic on metre and narrow gauges Disadvantages of Kankar It is very soft and can be reduced to powder form easily, hence, making the track dusty. The maintenance of track is very difficult 6. Moorum The decomposition of laterite results into the formation of moorum. It has red and sometimes yellow color. The best moorum is that which contains large quantities of small laterite stones. Advantages of Moorum Moorum is good materials for ballast when other material for ballast is not available. Moorum can be safely used on newly laid track and acts as a soling when broken stones are laid afterwards. Moorum has got good drainage properties Disadvantages of Moorum Moorum is very soft and reduces to powder and hence to dust form in short time. Maintenance of tracks laid with this material is difficult 7. Brick Ballast Or Brick Bats Sometimes the broken pieces of over burnt bricks, called brickbats, are used as materials for ballast. Advantages of Brick Ballast It has got excellent drainage properties They can be used as good ballast material where suitable material for ballast is either unavailable or uneconomical Disadvantages of Brick Ballast Brickbats turn down into powder form easily and hence the track becomes dusty Maintenance of the track laid with this material as ballast is very difficult. Rails are often corrugated on the tracks laid with this material as ballast 8. Selected Earth Selected earth may be used as material for railway ballast for sidings and also for newly laid tracks.

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Materials for Railway Ballast on the Railway Track

Materials for Ballast Railway Engineering Notes

The following materials for Railway Ballast used on the railway track.

1. Broken Stone

2. Gravel

3. Cinders / Ashes

4. Sand

5. Kankar

6. Moorum

7. Brick Ballast

8. Selected Earth

1. Broken Stone

Broken stone is one of the best materials for railway ballst to be used on the railway tracks. Almost all the important railway tracks are provided with broken stone.

The stone to be used as railway ballast should be hard, tough nonporous and should not decompose when exposed to air and light. Igneous rocks like quartzite and granite forms the excellent ballast materials. When these are not available then lime stone and sand stone can also be used as good ballast material.

Advantages of Broken Stone

It holds the track in position
It is good for heavy traffic
It can serve high speeds equally well.

Disadvantages of Broken Stone

The main disadvantage is that it is expensive in its initial cost.

2. Gravel

Gravel ranks next in its suitability for use as materials for ballast and is used in many countries of the world in very large quantities. Gravel consists of worn fragments of rocks occurring in natural deposits. Gravel or shingle may be obtained from river bed or it may be dug out from gravel pits.

Advantages of Gravel

It is cheaper in its cost as it has not to be broken as like stone ballast
It has got excellent drainage properties, if properly cleaned

Disadvantages of Gravel

It easily rolls down under the vibrations and packing under the sleepers get tense
The variation in size is considerable and hence requires screening before use
Grovel as obtained from gravel pits, is full of earth and hence requires proper cleaning if proper drainage of the track is to be done.

3. Cinders Or Ashes

The residue from the coal in locomotives or other furnaces is called cinder or ashes. It is one of the universal forms of ballast as it is a byproduct of all the railway which uses coal as a fuel.

Advantages of Cinders or Ashes

Handling of the material is not cumbersome this material can be handle easily
Cost is very low and hence can also be used for sidings
It has got fairly good drainage properties
Large quantities of this material can be made available at short notice.
In case of emergence such as caused by the destruction of portion of railway track during floods. This material proves to be very useful and is used in the formation repairing as well as for packing of track.

Disadvantages of Cinders or Ashes

It is highly corrosive and cannot be used where steel sleepers are fixed
The foot of the rails get affected due to use of this type of material as ballast
It is very soft and can easily be reduced to powder under vibrations and hence the track becomes very dusty. This is objectionable particularly in dry weather.

4. Sand

Sand is another good materials for railway ballast , coarser sand is to be preferred to finer sand and the best sand is that which contains a quantity of fine gravel varying in size from 1/8 upwards.

Advantages of Sand

If the sand is free from earth and vegetation then it has good excellent properties to drain off water immediately
It is cheaper if available in nearby locality
It produces very silent track and hence are suitable for packing cast iron pot sleepers.

Disadvantages of Sand

It gets easily disturbed under vibrations and hence its maintenance is very difficult
The sand can be easily washed off or blown away and hence requires frequent renewal.
The sand particles may get into the moving parts of the vehicles and produces friction. This leads to heavy wear of vehicles

5. Kankar

Kankar a lime agglomerate is found in many places in the form of nodules of varying sizes.

Advantages of Kankar

Kankar is suitable Materials for ballast when other good material for ballast is not available or if available uneconomically.
Kankar is good for light traffic on metre and narrow gauges

Disadvantages of Kankar

It is very soft and can be reduced to powder form easily, hence, making the track dusty.
The maintenance of track is very difficult

6. Moorum

The decomposition of laterite results into the formation of moorum. It has red and sometimes yellow color. The best moorum is that which contains large quantities of small laterite stones.

Advantages of Moorum

Moorum is good materials for ballast when other material for ballast is not available.
Moorum can be safely used on newly laid track and acts as a soling when broken stones are laid afterwards.
Moorum has got good drainage properties

Disadvantages of Moorum

Moorum is very soft and reduces to powder and hence to dust form in short time.
Maintenance of tracks laid with this material is difficult

7. Brick Ballast Or Brick Bats

Sometimes the broken pieces of over burnt bricks, called brickbats, are used as materials for ballast.

Advantages of Brick Ballast

It has got excellent drainage properties
They can be used as good ballast material where suitable material for ballast is either unavailable or uneconomical

Disadvantages of Brick Ballast

Brickbats turn down into powder form easily and hence the track becomes dusty
Maintenance of the track laid with this material as ballast is very difficult.
Rails are often corrugated on the tracks laid with this material as ballast

8. Selected Earth

Selected earth may be used as material for railway ballast for sidings and also for newly laid tracks.

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Soil Stabilization and Railway Track (pdf) Sometimes it becomes unavoidable to lay tracks on a very poor (or undesirable) soil. In such cases it becomes necessary to improve and strengthen the nature of soil by some suitable methods. Under such circumstances, the following methods are used. 1. Layer of Moorum 2. Cement Grouting 3. Sand Piles 4. Use of Chemicals 1. Layer of Moorum This method is widely used and is adopted if a poor quality soil comes across a track such as black cotton soil which is a fine black loomy soil. This soil has the tendency of expanding (or swelling) when moist and of caking and cracking heavily when dry. Tracks laid on formation of maintain. In rainy season, the soil fills up ballast interest less, the track in the worst places gets sodden and spongy track is reduced. In hot weather, the cracks are formed and the ballast is lost in filling up these cracks. Thus, the alignment as well as level is disturbed and with mud filling the interstices, the track loses. Its resiliency, therefore, for these very reasons, a layer of moorum varying in thickness from 12" to 24" is laid under the ballast. This layer distributes the pressure of the load and prevents the ballast from being lost in the cracks of the soil. Instead of moorum, other materials such as ashes, concrete, slabs, rubber, unserviceable sleepers etc are also used and are found quite satisfactorily.

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Soil Stabilization and Railway Track (pdf)

Sometimes it becomes unavoidable to lay tracks on a very poor (or undesirable) soil. In such cases it becomes necessary to improve and strengthen the nature of soil by some suitable methods. Under such circumstances, the following methods are used.

1. Layer of Moorum

2. Cement Grouting

3. Sand Piles

4. Use of Chemicals

1. Layer of Moorum

This method is widely used and is adopted if a poor quality soil comes across a track such as black cotton soil which is a fine black loomy soil. This soil has the tendency of expanding (or swelling) when moist and of caking and cracking heavily when dry.

Tracks laid on formation of maintain. In rainy season, the soil fills up ballast interest less, the track in the worst places gets sodden and spongy track is reduced. In hot weather, the cracks are formed and the ballast is lost in filling up these cracks. Thus, the alignment as well as level is disturbed and with mud filling the interstices, the track loses. Its resiliency, therefore, for these very reasons, a layer of moorum varying in thickness from 12" to 24" is laid under the ballast. This layer distributes the pressure of the load and prevents the ballast from being lost in the cracks of the soil.

Instead of moorum, other materials such as ashes, concrete, slabs, rubber, unserviceable sleepers etc are also used and are found quite satisfactorily.

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2. Cement Grouting In this method, steel tubes of 1 1/4 " in diameter and 5ft long are driven into the formation at every alternate sleeper and near their ends as shown in figure. The tubes are driven into the foundation at an angle such that the end of tube is nearly under the rail. The cement grout is forced under a pressure of 100 psi through these tubes. The proportion of cement grout depends on the type and condition of formation. The concert grout spreads through the poor soil and consolidates it. The steel tubes are then gradually taken out.

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2. Cement Grouting

In this method, steel tubes of 1 1/4 " in diameter and 5ft long are driven into the formation at every alternate sleeper and near their ends as shown in figure. The tubes are driven into the foundation at an angle such that the end of tube is nearly under the rail. The cement grout is forced under a pressure of 100 psi through these tubes. The proportion of cement grout depends on the type and condition of formation. The concert grout spreads through the poor soil and consolidates it. The steel tubes are then gradually taken out.

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3. Sand Piles This method of strengthening the track laid on poor is most widely used in development countries like America. In this method, a vertical bore about 12" diameter is made in the ground by driving a wooden pile. The wooden pile is then withdrawn and the space is filled with sand and is well rammed. The sand piles are driven in the pattern as shown. It is also arranged that cross sectional area of the sand piles is about 20% of the formation area. Thus, the top section of the formation is covered with sand which makes the track stable on poor soil. 4. Use of Chemicals In this method, chemicals are used in place of cement grout to consolidate the soil. For example, silicate of soda followed by calcium chloride is effective for sandy soils containing less than 25% of silt and clay.

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3. Sand Piles

This method of strengthening the track laid on poor is most widely used in development countries like America. In this method, a vertical bore about 12" diameter is made in the ground by driving a wooden pile. The wooden pile is then withdrawn and the space is filled with sand and is well rammed. The sand piles are driven in the pattern as shown.

It is also arranged that cross sectional area of the sand piles is about 20% of the formation area. Thus, the top section of the formation is covered with sand which makes the track stable on poor soil.

4. Use of Chemicals

In this method, chemicals are used in place of cement grout to consolidate the soil. For example, silicate of soda followed by calcium chloride is effective for sandy soils containing less than 25% of silt and clay.

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Site for Railway Station Railway Engineering Notes ( pdf ) A railway station is defined as any place on a railway linewhere traffic is booked and dealt with and where an authority to proceed is given to the trains. Following factors should be considered while selecting a site for a railway station: 1. Drainage The proposed site should be on a fairly leveled ground and it should be well drained. 2. Water Supply There should be plentiful supply for water at the site of station. 3. Future Allowances There should be sufficient land available for the purpose of future extensions along both sides 4. Gradient The site should be such that permissible maximum gradients can be obtained without much difficulty. The vehicles may start moving with wind which is very hazardous. 5. Location or Horizontal Alignment The location of station yards should be such that it is neither located near a curve nor on a curve. 6. Vertical Alignment The train should not be situated in a sag but it should be on a summit. 7. Accessibility The station yards should be such that it is easily accessible from city or town. There should be well developed and efficient transportation system which leads the people and their goods to station with much ease. 8. Visibility The environment around the site selected for a station should be such that their exists clear and improved visibility for the drivers of trains. There should be certain enough arrangements made which improvements made which improves the visibility of a station. 9. Facilities The site selected for the station should be such that for the passengers of trains, machinery works, garages, workshops etc.

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Site for Railway Station Railway Engineering Notes ( pdf )

A railway station is defined as any place on a railway linewhere traffic is booked and dealt with and where an authority to proceed is given to the trains.

Following factors should be considered while selecting a site for a railway station:

1. Drainage

The proposed site should be on a fairly leveled ground and it should be well drained.

2. Water Supply

There should be plentiful supply for water at the site of station.

3. Future Allowances

There should be sufficient land available for the purpose of future extensions along both sides

4. Gradient

The site should be such that permissible maximum gradients can be obtained without much difficulty. The vehicles may start moving with wind which is very hazardous.

5. Location or Horizontal Alignment

The location of station yards should be such that it is neither located near a curve nor on a curve.

6. Vertical Alignment

The train should not be situated in a sag but it should be on a summit.

7. Accessibility

The station yards should be such that it is easily accessible from city or town. There should be well developed and efficient transportation system which leads the people and their goods to station with much ease.

8. Visibility

The environment around the site selected for a station should be such that their exists clear and improved visibility for the drivers of trains. There should be certain enough arrangements made which improvements made which improves the visibility of a station.

9. Facilities

The site selected for the station should be such that for the passengers of trains, machinery works, garages, workshops etc.

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Construction of Railway Track - Methods of Construction of Railway Tracks There are three distinct methods of construction of railway track. These are: 1. Telescopic Method 2. Tramline Method 3. Mechanical Method Telescopic Method of Construction of Railway Track In this method, rails, sleepers and fastenings are unloaded from the material train as close to the rail head as possible. The sleepers are carried by carts or men along the adjoining service road and spread on the ballast. The rails are then carried on pairs to the end of last pair of connected rails and linked. To carry rails manually over a long distance is a tedious job. So certain carriers called Anderson rail. Carriers are used to carry rails to the ends of the rail head. It can also take rails up to a head last pair linked with the help of temporary track consisting of 3" x 3" angle irons of the same length as rails and fastened to the sleepers. A further consignment of the material is deposited at the advances rails head and the procedure is repeated. Tramline Method Railway Track Construction This method is used where tram carrier are installed for carrying earthwork or in rainy season due to difficulty in movement of cart. Some tramline is established on with a gauge of 2'-2'-6". The basic difference between this and telescopic method lies in the conveyance and spreading of the sleepers. The track can be assembled at more than one points simultaneously, which is the great advantage of this method. Sometimes an additional track is laid on the side of existing track for which this method is best. Mechanical Method Railway Track Construction This method is extensively used in Britain and America by using special track laying machine. There are two types of machines available. In first type of machine, the track material carried by the material. Train is delivered at the rail head and laid in the required position by means of projecting arm or mounted on the truck nearest to the rail head. The material train moves forward on the assembled track and operation is repeated. In the second type of machines a long cantilevered arm projecting beyond. The wagon on which is fitted. A panel of assembled track consists of pair of rail with appropriate number of sleepers on the ballast layer. This panel is conveyed by special trolley running over the wagons of material train to the jibs. It is lowered by the jib in the required position and connected to the previous panel. The track laying machine then movies forwarded and operation is repeated.

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Construction of Railway Track - Methods of Construction of Railway Tracks

There are three distinct methods of construction of railway track. These are:

1. Telescopic Method

2. Tramline Method

3. Mechanical Method

Telescopic Method of Construction of Railway Track

In this method, rails, sleepers and fastenings are unloaded from the material train as close to the rail head as possible. The sleepers are carried by carts or men along the adjoining service road and spread on the ballast. The rails are then carried on pairs to the end of last pair of connected rails and linked.

To carry rails manually over a long distance is a tedious job. So certain carriers called Anderson rail. Carriers are used to carry rails to the ends of the rail head.

It can also take rails up to a head last pair linked with the help of temporary track consisting of 3" x 3" angle irons of the same length as rails and fastened to the sleepers.

A further consignment of the material is deposited at the advances rails head and the procedure is repeated.

Tramline Method Railway Track Construction

This method is used where tram carrier are installed for carrying earthwork or in rainy season due to difficulty in movement of cart. Some tramline is established on with a gauge of 2'-2'-6". The basic difference between this and telescopic method lies in the conveyance and spreading of the sleepers.

The track can be assembled at more than one points simultaneously, which is the great advantage of this method. Sometimes an additional track is laid on the side of existing track for which this method is best.

Mechanical Method Railway Track Construction

This method is extensively used in Britain and America by using special track laying machine. There are two types of machines available. In first type of machine, the track material carried by the material. Train is delivered at the rail head and laid in the required position by means of projecting arm or mounted on the truck nearest to the rail head. The material train moves forward on the assembled track and operation is repeated.

In the second type of machines a long cantilevered arm projecting beyond. The wagon on which is fitted. A panel of assembled track consists of pair of rail with appropriate number of sleepers on the ballast layer. This panel is conveyed by special trolley running over the wagons of material train to the jibs. It is lowered by the jib in the required position and connected to the previous panel. The track laying machine then movies forwarded and operation is repeated.

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Railway Sleepers - Types of Sleepers - Longitudinal, Transvers ( pdf ) Depending upon the position in a railway track, sleepers may be classified as: Longitudinal Sleepers Transverse Sleepers 1. Longitudinal Sleepers These are the early form of sleepers which are not commonly used nowadays. It consists of slabs of stones or pieces of woods placed parallel to and underneath the rails. To maintain correct gauge of the track, cross pieces are provided at regular intervals. At present this type of sleepers are discarded mainly because of the following reasons. Running of the train is not smooth when this type of sleepers is used. Noise created by the track is considerable. Cost is high. 2. Transverse Sleepers Transverse sleepers introduced in 1835 and since then they are universally used. They remove the drawbacks of longitudinal sleepers i.e. the transverse sleepers are economical, silent in operation and running of the train over these sleepers is smooth. Depending upon the material, the transverse sleepers may be classified as: Timber/wooden sleepers Steel sleepers Cast Iron Sleepers Concrete Sleepers Timber/Wooden Sleepers The timber sleepers nearly fulfilled all the requirements of ideal sleepers and hence they are universally used. The wood used may be like teak, sal etc or it may be coniferous like pine. The salient features of timber/wooden sleepers with advantages and disadvantages. Advantages of Timber Sleepers They are much useful for heavy loads and high speeds They have long life of 10-12 years depending upon the climate, condition, rain, intensity, nature of traffic, quality of wood etc Good insulators and hence good for track circuited railway tracks They are able to accommodate any gauge Suitable for salty regions and coastal areas Can be used with any section of rail Can be handled and placed easily They are not badly damaged in case of derailment They are not corroded Cheaper than any other types of sleepers Disadvantages of Timber Sleepers Liable to be attacked by vermin so, they must be properly treated before use Liable to catch fire They do not resist creep They are affected by dry and wet rot Become expensive day by day Life is shorter compare to others Steel sleepers They are in the form of steel trough inverted on which rails are fixed directly by keys or nuts and bolts and used along sufficient length of tracks. Advantages of Steel Sleepers Have a useful life of 20-25 years. Free from decay and are not attacked by vermins Connection between rail and sleeper is stronger Connection between rail and sleeper is simple More attention is not required after laying Having better lateral rigidity Good scrap value Suitable for high speeds and load Easy to handle Good resistance against creep Disadvantages of Steel sleepers Liable to corrosion by moisture and should not because in salty regions Good insulators and hence cannot be used in track circuited regions Cannot be used for all sections of rails and gauges Should not be laid with any other types of ballast except store Very costly Can badly damaged under derailments Way gauge is obtained if the keys are over driven The rail seat is weaker Having good shock absorber as there is not cushion between rail foot and ballast Cast Iron Sleepers They consist of two pots or plates with rib and connected by wrought iron tie bar of section of about 2" ½" each pot or plate is placed below each rail. The pot is oval in shape with larger diameter 2'-0" and smaller diameter 1'-8" is preferred. Plate sleepers consist of rectangular plates of size about 2' – 10' x 1' – 0". The relative advantages and disadvantages are given below. Advantages of Cast Iron Sleepers Long life upto 50-60 years High scrape value as they can be remolded Can be manufactured locally Provided sufficient bearing area Much stronger at the rail seat Prevent and check creep of rail They are not attacked by vermin Disadvantages Cast Iron Sleepers They are prone to corrosion and cannot be used in salty formations and coastal areas Not suitable for track circuited portions of railways Can badly damage under derailment Difficult to maintain the gauge as the two pots are independent Require a large number of fastening materials Difficult to handle and may be easily damaged Lack of good shock absorber They are expensive Concrete sleepers R.C.C and pre-stressed concrete sleepers are now replacing all other types of sleepers except to some special circumstances such as crossing bridges etc here timber sleepers are used. They were first of all used in France round about in 1914 but are common since 1950. They may be a twin block sleepers joined by an angle iron. It may be a single block pre-stressed type. Advantages Concrete Sleeprs Durable with life range from 40-50 years They can be produced on large quantities locally by installing a plant Heavier than all other types thus giving better lateral stability to the track Good insulators and thus suitable for use in track circuited lines Efficient in controlling creep They are not attacked by corrosion Free from attacks of vermin and decay, suitable for all types of soils Most suitable for welded tracks Prevent buckling more efficiently Initial cost is high but proves to be economical in long run Effectively and strongly hold the track to gauge Inflammable and fire resistant Disadvantages Concrete Sleepers Difficult to be handled Difficult to be manufactured in different sizes thus cannot be used in bridges and crossing Can be damaged easily while loading and unloading

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Railway Sleepers - Types of Sleepers - Longitudinal, Transvers ( pdf )

Depending upon the position in a railway track, sleepers may be classified as:

Longitudinal Sleepers
Transverse Sleepers

1. Longitudinal Sleepers

These are the early form of sleepers which are not commonly used nowadays. It consists of slabs of stones or pieces of woods placed parallel to and underneath the rails. To maintain correct gauge of the track, cross pieces are provided at regular intervals.

At present this type of sleepers are discarded mainly because of the following reasons.

Running of the train is not smooth when this type of sleepers is used.
Noise created by the track is considerable.
Cost is high.

2. Transverse Sleepers

Transverse sleepers introduced in 1835 and since then they are universally used. They remove the drawbacks of longitudinal sleepers i.e. the transverse sleepers are economical, silent in operation and running of the train over these sleepers is smooth. Depending upon the material, the transverse sleepers may be classified as:

Timber/wooden sleepers
Steel sleepers
Cast Iron Sleepers
Concrete Sleepers

Timber/Wooden Sleepers

The timber sleepers nearly fulfilled all the requirements of ideal sleepers and hence they are universally used. The wood used may be like teak, sal etc or it may be coniferous like pine.

The salient features of timber/wooden sleepers with advantages and disadvantages.

Advantages of Timber Sleepers

They are much useful for heavy loads and high speeds
They have long life of 10-12 years depending upon the climate, condition, rain, intensity, nature of traffic, quality of wood etc
Good insulators and hence good for track circuited railway tracks
They are able to accommodate any gauge
Suitable for salty regions and coastal areas
Can be used with any section of rail
Can be handled and placed easily
They are not badly damaged in case of derailment
They are not corroded
Cheaper than any other types of sleepers

Disadvantages of Timber Sleepers

Liable to be attacked by vermin so, they must be properly treated before use
Liable to catch fire
They do not resist creep
They are affected by dry and wet rot
Become expensive day by day
Life is shorter compare to others

Steel sleepers

They are in the form of steel trough inverted on which rails are fixed directly by keys or nuts and bolts and used along sufficient length of tracks.

Advantages of Steel Sleepers

Have a useful life of 20-25 years.
Free from decay and are not attacked by vermins
Connection between rail and sleeper is stronger
Connection between rail and sleeper is simple
More attention is not required after laying
Having better lateral rigidity
Good scrap value
Suitable for high speeds and load
Easy to handle
Good resistance against creep

Disadvantages of Steel sleepers

Liable to corrosion by moisture and should not because in salty regions
Good insulators and hence cannot be used in track circuited regions
Cannot be used for all sections of rails and gauges
Should not be laid with any other types of ballast except store
Very costly
Can badly damaged under derailments
Way gauge is obtained if the keys are over driven
The rail seat is weaker
Having good shock absorber as there is not cushion between rail foot and ballast

Cast Iron Sleepers

They consist of two pots or plates with rib and connected by wrought iron tie bar of section of about 2" ½" each pot or plate is placed below each rail. The pot is oval in shape with larger diameter 2'-0" and smaller diameter 1'-8" is preferred. Plate sleepers consist of rectangular plates of size about 2' – 10' x 1' – 0".

The relative advantages and disadvantages are given below.

Advantages of Cast Iron Sleepers

Long life upto 50-60 years
High scrape value as they can be remolded
Can be manufactured locally
Provided sufficient bearing area
Much stronger at the rail seat
Prevent and check creep of rail
They are not attacked by vermin

Disadvantages Cast Iron Sleepers

They are prone to corrosion and cannot be used in salty formations and coastal areas
Not suitable for track circuited portions of railways
Can badly damage under derailment
Difficult to maintain the gauge as the two pots are independent
Require a large number of fastening materials
Difficult to handle and may be easily damaged
Lack of good shock absorber
They are expensive

Concrete sleepers

R.C.C and pre-stressed concrete sleepers are now replacing all other types of sleepers except to some special circumstances such as crossing bridges etc here timber sleepers are used. They were first of all used in France round about in 1914 but are common since 1950. They may be a twin block sleepers joined by an angle iron. It may be a single block pre-stressed type.

Advantages Concrete Sleeprs

Durable with life range from 40-50 years
They can be produced on large quantities locally by installing a plant
Heavier than all other types thus giving better lateral stability to the track
Good insulators and thus suitable for use in track circuited lines
Efficient in controlling creep
They are not attacked by corrosion
Free from attacks of vermin and decay, suitable for all types of soils
Most suitable for welded tracks
Prevent buckling more efficiently
Initial cost is high but proves to be economical in long run
Effectively and strongly hold the track to gauge
Inflammable and fire resistant

Disadvantages Concrete Sleepers

Difficult to be handled
Difficult to be manufactured in different sizes thus cannot be used in bridges and crossing
Can be damaged easily while loading and unloading

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