PERMANENT WAY
The railway track of permanent nature which handles the normal commercial traffic regularly is called a permanent way. The purpose or use Of a permanent way is to provide permanent facility for safe and quick movements of normal commercial traffic between the starting and destination stations.
Basically a track consists of two parallel rails having a specified distance between them and fastened to the sleepers.
Typical Cross Section of a Permanent way
Various component of permanent way are
1. Rails
2. Sleepers
3. Ballast
4. Fittings and fastenings
5. Formation
Functions of each components
1) Rails:
are steel girders over which the train moves and transmit the wheel loads of trains to the sleepers below.
2) Sleepers:
The sleepers hold the rails in proper position and provide a correct gauge with the help of fittings and fastenings and transfer the train load to the ballast below.
3) Ballast:
The ballast distributes the load over the formation and holds the
Sleepers in position and provides a uniform level surface. They also provide drainage to the track and transfer the train load to a larger area of formation below
4) Fittings and fastenings:
They provide a grip between rails and sleepers. The rails are joined to each other by fishplates and bolts and the rails are fastened to the sleepers with the help of various fittings such as spikes and keys.
5) Formation:
Formation is the base of the track. it takes the total load of track and the trains move on it.
REQUIREMENTS OF AN IDEAL PERMANENT WAY
Following are some of the basic requirements of a permanent way:
a. The gauge should be correct and uniform.
b. Both rails should be at the same level.
c. Curves should be properly designed.
d. The alignment should be short, easy, safe and economical.
e. The gradient should be even and uniform throughout the length of the. track.
f. The track should be resilient and elastic in order to absorb shocks and vibrations of running
g. The permanent way should be sufficiently strong against lateral forces.
h. Proper super elevation should be provided on curves.
i. Proper drainage should be provided.
j. Joints, including points and crossings which are regarded to be weakest points of the railway track, should be designed and maintained.
k. The creep should be minimum.
l. The various components of the track, i.e., the rails, fittings, sleepers, ballast and formation 
must fully satisfy the requirements for which they have been provided.
m. The friction between the wheels of the rolling stock and rails should be minimum.
n. The track components should be easy to repair, replace and re-used.
o. The track structure should be strong, low in initial cost as well as maintenance cost.
p. It should be provided with fence near level crossings and also in urban areas.
q. The track should possess anti theft and sabotage qualities.
r. It should be provided with safe and strong bridges coming in the alignment of the track.
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