1. CE2303 Railway Engineering
Station and Yards
CE2303 Railway Engineering

2. Definition
A railway station is the selected place on a railway line, where trains halt for one or more of the following purposes:

3. For exchange of passengers
For exchange of goods
For control of train movement
To enable the trains on a single line track to cross from opposite direction
For taking diesel, water etc.
For sorting of bogies
In case of emergencies (accident/dislocation of track due to heavy rain)

4. Site Selection
For selecting a site for a railway station, following factors should be considered:

5. Acquisition of Land
Sufficient land area including land width for a single track or double track system and extra area to accommodate additional line, station buildings, platforms, cabins, staff quarters, future extension etc.

7. Proximity
The station site should be close to the town or village as far as possible to facilitate the transport of passengers and goods.

8. Nature of Land
The land area should preferably be a level ground for convenient and safety of marshalling and shunting wagons.

9. Nature of Land
Steep gradient may cause the wagons to move even when not in operation due to high wind velocities and may cause accidents.

10. Nature of Land
In India, maximum permissible gradient for all gauges, in station yards is 1 in 400, with desirable value of 1 in 1000.

11. Approach Road
It is highly essential to encourage rail transport by providing approach roads connecting a town or village to station site.

12. Approach Road
Maximum transport facilities should be provided for the type of traffic likely to be handled by the approach roads.

13. Station Site Alignment
Station site should never be located on curves and as far as possible should not be near the curve too.

14. Station Site Alignment
The alignment of track for both approaching and departing trains should be straight otherwise the signals will either be difficult to sight or out of sight.

15. Site Drainage
The site should have quick drainage facilities and minimum grade of 1 in 1000 is recommended for this purpose.

16. Station Amenities
Amenities like water supply, coal, diesel, electricity etc. should be provided at the station site.

17. Station Amenities
A plentiful supply of drinkable water is essential.

18. Signal Aspects & Indications

19. Stop Signals
A stop signal governs access to a block section and ordinarily may not be passed when it is at its most restrictive indication (the on position, which shows the stop or danger indication of these signals)

20. Semaphore Stop Signal

21. Colour Light (CL)
Stop Signal may have two (2CL: green above red), three (3CL: Green-Yellow-Red) or four lamps (MACL: Yellow-Green-Yellow -Red).

22. 2CL

23. 3CL

24. MACL

25. Stop Signal
Usually the signals are set up at sufficient distance so that, for instance, a train arriving at a caution signal at the maximum speed for the section can safely brake to a halt before the next signal which is at STOP.

26. Stop Signal
If the distance between the signal at caution and the signal at danger is less than the safe braking distance, the signal to the rear displaying attention also serves to alert driver that the train have to be slowed down.

29. Classification of Railway Stations

30. Classification
Stations can be classified according to operational and functional characteristics in the following categories:

31. Operational Classification
Block Stations – Class A, Class B and Class C stations in descending order of importance
Non-block Stations – Class D Stations and flag stations
Special class stations

32. Functional Classification
None-junction or wayside stations
Junction stations
Terminal stations

33. Block Stations
Block Stations which are sort of compartments into which the railway line is divided, are established so as to safety space the trains behind each other.

34. Block Stations
The ‘Block Stations’ are made at the ends of block section and are equipped with signals which demarcate the limits of the block sections.

35. Block Stations
A block station is a place on the railway line at which “permission to approach” and “authority to proceed” are granted.

36. ‘A’ Class Station
“A Class” is a station where the line has to be cleared upto an adequate distance (400 m) beyond the home signal for giving permission to approach to a train.

37. ‘A’ Class Station Home Signal – which is the first stop signal
Starter Signal – Placed at an adequate distance from home signal. It marks the line up to which the line should be clear, for giving permission to approach
Warner Signal – placed at a warning distance from the home signal to indicate whether the section beyond is clear or not

38. Warner Signal

39. ‘B’ Class Station
A “B Class” station is one, where the line has to be cleared up to an adequate distance (180 m) beyond the outer signal before giving permission to approach to a train.

40. ‘B’ Class Station An Outer Signal – which is first stop signal
A Home Signal – placed at an adequate distance from the outer signal
It is the practice to place the outer signal at a single line station at a distance of 580 m from the home signal.

41. ‘C’ Class Station
A “C Class” station is only a ‘block hut’ where no passengers are booked. It is used as a means to split a long block section so that the interval between successive trains is reduced.

42. ‘C’ Class Station A Home Signal – which is first stop signal
A Warner Signal – placed at an adequate warning distance from home signal
Trains usually do not stop at these stations.

43. Non-Block Stations
These are also called “D Class” or flag stations. These are situated between two consecutive block stations. They do not define boundary.

44. Functional Classification
Non Junction or wayside station
Junction Station
Terminal Station

45. Wayside Stations
These stations consist of an arrangement for crossing an up and a down train or for overtaking the slower trains by the fast moving train.

48. B.O. – Booking Office; W.H. – Waiting Hall; S.H. – Sand Hump

49. Junction Stations
A junction station is one where a brach line joins a main line and at such junctions special arrangements are made for interchange of traffic (underpass) and engine service etc..

51. Turntable

52. Terminal Stations
The station, at which a railway line or one of its branches terminates or continuity of line stops, is known as terminal stations.

55. Stations will have signals which allows trains to depart from a station when it is desired to do so. To signal a train to despatech from a station signals are located at the exit point of each line on which trains wait at stations. Signals S7 and S9 in figure 4 shows such signals. These signals are referred to as Starter signals and allows trains to depart from the tracks behind them. The tracks from which the starter signals allow departure are referred to normally as berthing tracks. Quite often a signal ahead of the starter signals are placed ahead of all the converging tracks as S11. This signal is referred to as Advance starter signal and allows better management of trains within the stations.

56. In bigger stations facilities for adding or stabling of coaches or wagons are provided. These are by the provision of short length of lines connected to one of the berthing tracks and these are known as sidings. In other instances there may be need of  attaching coach or locomotive of a train on one berthing track and add to a train on another berthing track.
The availability of advance starter signal is for facilitating such movements. For such movements a separate type of signal is used referred to as shunt signals.
Signal S101 and S102 are shunt signals allowing shunt movements from and to the siding as shown