 Hello everyone, myself, Ms. Shailaja Diwarkonda, Assistant Professor in Civil Engineering Department, Volchian Institute of Technology, Solapur. In today's lecture, we are going to study modes of transportation, railways. Learning outcomes of this lecture. At the end of this video, the viewers will be able to explain importance of railway transport, elements of the railways and types of the railways. It is the means of transportation on vehicles which run on the track, which track is nothing but rails. It is one of the most important transportations commonly used and very cost effective modes of communicating and good carriage over long as well as short distances. Roadways are cheaper than railways. After the road transport, we can mostly preferred for the railway transport. The first train in India was ran from Red Hills to Chaitra Deepet Bridge in 1837. It was called Red Hill Railway and used a rotary steam locomotive and was mainly used for transporting granite stones for road building works. The first passenger train in India ran between Bombay to Dhane on 16th April 1853 and it is ran over the span of 34 kilometers. So these are the various elements of the railway track. The railway track consists of first natural subgrade, then over it formation level, then ballast, sleepers, fastenings and rails. So this formation level and subgrade is nothing but the foundation for the railway track to provide the stability and safe transport of the trains over the rails. It elements of the railway. As I told the after formation level, here it is natural subgrade, then over it formation level. Then the first element of the railway track is ballast. So in this figure you can see the part of the lower most part of the railway track which is mostly having aggregates of size 20 mm to 65 mm is called as ballast bed. Ballast is the granular granular material usually broken stones or bricks, single and conker gravel and sand placed and packed and around the sleepers to transfer the load from the sleepers to the formation level. Sleeper means here in this figure you can see these horizontal members are called as sleeper means whatever load comes from the train it is transferred to the rails, from rails it is transferred to the sleepers and it is uniformly distributed to the ballast formation. And again from ballast it is distributed to the natural subgrade. Then next is rails. Normally we can see the only this upper most part of the rails. These rails are made up of steel sections. The rolled steel sections laid end to end in two parallel lines over sleepers to form a railway track are known as rails. So in these rails we are having various types that is double headed rails, flat footed rails, bull headed rails. This figure we have shown it is double headed rails. Double headed rail it means the head and foot means the both sections upper and lower section are of the same size. The rails are having their head and foot of same dimensions are known as double headed rails. These rails have less strength and stiffness as compared to the flat footed rails. Then flat footed rails in this figure it is shown as flat footed rails. It means the lower part of the rail section is flat. So it is called as flat footed rails. These rails have more strength and stiffness than other rails. These rails are less costly than other type of rails. Bull headed rails. The rail section having their head little thicker and stronger than the lower most part. If you see this figure at this top section it is little bit more in dimension as compared to the cross section at the lower side. So it is called as bull headed rails. They keep better alignment and give a more solid and smoother track. They have less strength and stiffness. So from these 3 types of rails the flat footed rails are having more strength and stiffness. Now the figure shows the various joints of the rails. When we prepare the railway track it is not just we have to place the rails on sleepers but we have to fix up it. So to fix up this rail railway tracks we have to use some fixtures and fastening. So this figure shows the typical cross section of the rail joint. In this figure you can observe the lower most part is ballast and over ballast the sleepers are placed and again these rails are placed over these sleepers. Again these rails are fitted or fixed with the help of this chair, chair bolts, fish bolt or fish plate to the sleepers. This rail joints are most important to keep the rails in the rail in proper stability and to avoid the vibration or sleeping of the train from the railway track. So the most important part in the railway track is these rail joints. So normally rail joints are having fish plate joint, fish fasteners, side chairs, junction plate, bearing plate and chairs. Now the next part of the railway track is sleepers. In this figure you can observe this horizontal member which is called as sleeper. Sleepers are the members generally laid transferred to the rails on which the rails are fixed to transfer the load from the train to the ballast and the sub grade. Again we are having the different types of these sleepers. Normally we have wooden sleepers, metal sleepers and concrete sleepers. Now you can see in this figure it is the wooden type of sleepers. Earlier days mostly we are using the wooden type of sleepers and in our days we are using metal sleepers as well as concrete sleepers. So metal sleepers and concrete sleepers provide the more stability to the rail track than the wooden sleepers. Gauge, what is mean by rail gauge? Rail gauge is nothing but the inner distance between the two rails. If you observe this figure gauge means it is the inner distance between the two rails. So you can called as width of the railway track. Again there are various types of rail gauges. Standard gauge, broad gauge, meter gauge and narrow gauge. In India normally we will use this broad gauge, meter gauge and narrow gauge. These are the various types of rail gauges. Standard gauge is having length of 1.524 meter to 1.435 meter. These type of gauges are mostly used in Europe, North America, China, Korea, Australia etc. In India normally we will use broad gauge, meter gauge and narrow gauge. Gauge is having the length of 1.676 meter to 1.524 meter. It is used when sufficient funds are available and the prospect of revenue are very high. Normally the broad gauge is used in plain areas. Meter gauge, meter gauge is having the length of 1 meter and it is used when sufficient funds are not available and this gauge is used in under development areas. Gauge is having the length of 0.762 meter to 0.610 meter. When the construction of track with a wider gauge is prohibited due to the provision of sharp curves, steep gradient or narrow bridges and tunnels, in that case we go for the narrow gauges. So these are the different types of rail gauges and their suitabilities. Now you pause this video and try to answer these questions. These are the answers for the given questions. These are the references used for the further study. Thank you.