Railways

Concrete

Concrete Sleepers

abbu riyaz 1 May, 2023

Concrete Sleepers introduces in the modern construction of railway tracks. Mainly sleepers are of concrete, timbers, steel, cast iron. In thees various types of sleepers, due to need for better design and economy of sleeper on sustainable basis Concrete Sleepers engages.

These are the members which lay transverse to the rails on which the rail supports and fixes. Sleepers are concrete beds in the railway tracks. The main role of sleepers is to transfer load from rails to the ballast. And the sub-grade below. It as a transverse member throughout the permanent way.

Concrete Sleepers

It is using more than any other sleepers because of its unique properties. They are more resistant to wear and tear. It withstands blows and vibrations cause due to heavy moving loads. And it is fewer subjects to chemical attacks, termite attacks, and more corrosion resistance.

There are two types of sleepers they are,

Reinforced and
Pre-stressed Concrete sleepers

Concrete is the best and suitable material for sleepers in railway tracks. Some of the main and important features are as follows,

It is a strong and homogeneous material
Not affect by moisture
Unaffected by chemical attacks
High resistance to wear and tear
Unaffected by sub-soil salts

Advantages of Concrete Sleepers

It is having a maximum life compare to other sleeper forms.

No difficulties in the track circuiting.

Not affect easily by moisture, termites, white ants, insect attacks.

Having a high load carrying capacity.

High tendency to absorb shocks and vibrations.

Withstands wear and tear due to heavy moving loads.

Disadvantages of Concrete Sleepers

Weight is high compared to other types of sleepers.

It requires more fittings like pads, plugs,etc.

In derailment of sleepers the damages are very heavy.

After the life completes it is not re-usable therefore the scrap value is low.

Construction materials

Metal Sleepers Advantages and Disadvantages

abbu riyaz 1 May, 2023

The Metal Sleepers Advantages and Disadvantages are discussed in this post. Railway Track Sleepers are members which lay transverse to the rails on which the rail supports and fixes. Sleepers are beds in the railway tracks. The main reason to use metal sleepers replacing wooden sleepers are because of insufficiency of wooden sleepers. Metal sleepers use widely in the modern construction of railway tracks. The main role of sleepers is to transfer load from rails to the ballast. The Metal sleepers are of cast iron and steel.

These sleepers fix vertical to each other. It fixes throughout the track. The main work of sleepers is to hold rails in a strong position. It receives the loads from rails and spread to ballast and sub-grades. In these various types of Metal sleepers, the sleeper which is economic uses in the construction of railway tracks. Even though it use mostly in the modern construction of railway rail track it posses many advantages and disadvantages.

Metal Sleepers Advantages and Disadvantages

Advantages

There are many important advantages of metal sleepers. The main advantages of metal sleepers are as follows,

Metal sleepers are uniform in strength and durability.
For metal sleepers no frequent renewal requires.
It is economical and have longer life.
Low maintenance and easier repair.
Gauges are easy to maintain and adjustable.
Easy in manufacturing and laying.
The fitting operation is better and it makes less occurrence of creep.
It is fireproof.
It is reusable and have a good scrap value.
The manufacturing of sleepers is a simple process.
The fixtures of the sleepers are less in number and simple in nature.

Disadvantages

Metal sleepers having many good advantages still it posses some disadvantages in it. The disadvantages of metal sleepers are as follows,

More ballast requires for metal sleepers
Difficult to maintain due to rust and other chemical gents in atmosphere.

And it is more likely subjects to corrosion/rusting.
As a good conductor of electricity it interferes with track circuiting.
It is not suitable for level crossings and bridges.
Unsuitable in case of pointing.
Creep occurs frequently.
It subjects easily to deform and bend due to heavy moving loads in it.
Suitable only for stone ballasts.
Cracks develop easily in metal sleeper seats through the holes of bolts.
More care has to take to maintain steel sleepers.

The Metal Sleepers Advantages and Disadvantages are considering to handle the difficulties in the construction of modern railway rail tracks.

civil techniques

Types of Metal Sleepers

abbu riyaz 1 May, 2023

There are many Types of Metal Sleepers using in the construction of railway rail tracks. As it satisfies all the needs of a sleeper it is using mostly in the construction of railway rail tracks.

Types of Metal Sleepers

There are many Types of metal Sleepers using in the construction of railway rail tracks. The following types of Metal Sleepers are as follows,

Cast iron Sleepers and

Steel Sleepers

1. Cast iron Sleepers

The Cast iron sleepers are using widely in the construction of railway rail tracks. Cast iron are of many types as follows,

Bowl or Pot sleepers
Plate sleepers
Box sleepers
C.S.T-9 sleepers
Rail Free Duplex sleepers.

Bowl or Pot sleepers

It consists of two bowl or pots placed inverts on ballast. The main feature of these sleeper are, that it is on the top of pot a rail seat or a chair provides to hold the flat footed and Bull headed rails.

Plate sleepers

These Plate sleepers are rectangular in shape. The plates are parallel to the rails. The plates are fix in position with the tie bars. These connections are being similar to that of pot sleepers. The pot and plate sleepers are us with flat footed and Bull headed rails.

Box Sleepers

Box Sleepers are in box shapes. The box sleepers are not using nowadays in the modern construction of railway rail tracks.

C.S.T-9 sleepers

It has a triangular inverted pot on either side of the rail seat. And having a plate with a projecting rib and a box on the top of the plate. The connections are by means of rods of various types. These sleepers are easily assemble and dismantle without using mechanical equipment.

Rail Free Duplex sleepers

A joint sleeper of cast iron known as rail Free Duplex sleepers has been use as a rail joints in conjunction with it. These sleepers use to prevent the cantilever action between the two supports of the sleeper joints

2. Steel Sleepers

Most of the tracks lays with the metal sleepers. The following types of Steel Sleepers are as follows,

Key Type
Clip-Bolt Type
Spring Type

Key Type

Keys are use to hold the rail in sleepers. These keys are fix on both sides of sleepers to hold it tight. These keys are fix on opposite directions to each other.

clip-Bolt Type

This sleeper employs a bolt and clip for holding the rail. The four clip and bolt use for holding the rails. By using different types of the clips the sleepers use for any section of rail. The size of clip depends upon the weight of rails.

Spring Type

The rail seat is strengthened by a spring plate having two holes in sleepers on either sides.

civil techniques

Metal Sleepers

abbu riyaz 1 May, 2023

Metal sleepers use widely in the modern construction of railway tracks. The Metal sleepers are of cast iron and steel. In these various types of Metal sleepers, the sleeper which is economic uses in the construction of railway tracks.

Cast iron is widely engaging than steel because of its less tendency to corrosion. Metal sleepers use widely because of the shortage of wooden sleepers and its long life properties.

Types of Metal Sleepers

There are many Types of Metal Sleepers using in the construction of railway rail tracks. The following types are as follows,

Cast iron Sleepers and

Steel Sleepers

Cast iron Sleepers

The Cast iron sleepers are using widely in the construction of railway rail tracks. Cast iron are of many types as follows,

Bowl or Pot sleepers
Plate sleepers
Box sleepers
C.S.T-9 sleepers
Rail Free Duplex sleepers.

The main reason to use metal sleepers replacing wooden sleepers are because of growing scarcity of wooden sleepers.

Steel Sleepers

The following types of Steel Sleepers are as follows,

Key Type
Clip-Bolt Type
Spring Type

Requirements of Metal sleepers

Metal Sleeper should bears the compression and tensile stress acting on it.
It should be of low manufacturing cost and low maintenance.
It should provide proper grip on the rail track
And provide ballast to prevent dislocation of track due to vibrations and shocks cause by heavy loads.
Sleepers must be economical.
t should be easier to handle during the maintenance operations like lifting, packing, removal, and replacement.
The weight of sleepers should not be too heavy or too light.
It should have a moderate weight for ease of access.
And capable to resist shocks of rails because of a fast-moving load with vibration.
It should have a proper spacing between two sleepers for ease of maintenance for removal and replacement.
Sleeper to design in a way that they should not push out easily due to moving loads.
A sleeper to provide with anti-theft qualities.

Construction materials

Types of wooden Sleepers

abbu riyaz 1 May, 2023

There are many Types of wooden Sleepers using in the construction of railway rail tracks. As it satisfies all the needs of a sleeper it is using mostly in the construction of railway rail tracks.

Types of wooden Sleepers

There are many Types of wooden Sleepers using in the construction of railway rail tracks. The following types of wooden Sleepers are as follows,

Hardwood and

Softwood

EKKA, SAL, TEAK are some of the most using types of sleepers in the construction of railway rail tracks. These wooden sleepers are hard than any other wooden sleepers. It is heaver too.

Treatment of wooden Sleepers

The lifetime of wooden Sleepers increases 30% – 50% by treatment. There are so many chemical treatments involves in the treatment of wooden Sleepers. There are three main methods for treating timber sleepers

Full cell process
Empty cell process
Haskenizings process

Timber has millions of minute cells. These cells have many ingredients in it. The removal and refilling of ingredients are the treatment of timber sleeper.

Methods of Construction wooden Sleepers

There are many important methods of construction of wooden Sleepers.

The good looking fair wooden Sleepers to use on each side of rail joints.

The sleepers to lay centrally along tracks.

Place good side of sleepers downwards and poor side upside.

The sleepers to place at exactly 90 degrees.

The correct size of drills to make in sleepers for fixing.

A proper and correct spacing to maintain in the laying of track.

Enough air and ventilation to provide at stacking of wooden sleepers.

Extra and spare holes to pack with a wooden plug to avoid entry of water inside the track.

civil techniques

Wooden sleepers in Railway Tracks

abbu riyaz 1 May, 2023

Wooden sleepers in Railway Tracks plays a major role. It is the best. And it satisfies all the needs of a sleeper. In the Railway bridges, the railway rail tracks are of timber sleepers. It is because of its less weight, high load carrying capacity and its ability to absorb shocks and vibrations. The lifetime of wooden sleepers depends upon the ability to resist all chemical, physical and mechanical deformations.

The chemical deformations are damages because of the chemical attacks in woods, like efflorescences.

The physical deformations are because of the insect attacks like termites, white ants, decay, etc.

The mechanical deformations are the damages by the abrasions and wear & tear because of heavy moving loads in high-speed tracks.

1. Specifications of the wooden sleepers

It should be free from cracks, and other defects.

It should sound through.

And should be straight without curves.

It should saw parallel on the top and bottom faces.

Edges are of a square shape.

2. Advantages of the Timber sleepers

Timber sleepers are easily available.

It is easy to lay and construct a railway rail track.

Lightweight material.

Having a high load carrying capacity.

High tendency to absorb shocks and vibrations.

Having simple and easy fittings.

Easy to maintain and repair tracks.

Low maintenance cost.

Highly economic.

Gives less noisy track.

Require fewer fittings and simple design.

Withstands wear and tear due to heavy moving loads.

3. Disadvantages of the Timber sleepers

Gets easily attack by termites, white ants, insects.

Difficult to maintain the gauge of rails.

Difficult to maintain track alignment.

Less lifetime compares to other sleepers types.

wooden Sleepers are the old traditional material used in the construction of railway track sleepers. It satisfies all needs of a good sleeper. The life of wooden sleepers depends on many facts like wear and tear, decay, and attack by termites, etc. And because of a high scarcity of wooden sleepers, it is replacing with the metal and concrete sleepers.