1. Geometric Design of Railway Track
CE2303 Railway Engineering

2. Introduction Parameters determines or affect geometry of the track
Gradient
Speed
Super-elevation etc.
Parameter: A numerical or measurable factor forming one of a set that defines a system or sets the conditions of its operation.

3. Introduction Most of the train derailment due to: Track Defects
Vehicular Defect
Operational Defect
Civil Engineer is mainly concerned with track defects

4. Introduction
Engineer should aware of the track defects and how to remove those defects so that no derailment takes place.
Broken Rail

5. Introduction
Railway track should be designed, suiting to load and speed of the train, and meeting the safety and economy requirements.

6. Introduction
A train may derail on the straight track due to the following defects in the track:
Defective cross-levels
Defective alignment
Defective Gauge
Low joints

7. Cross-levels

8. Rail Joint – unless uniform level

9. Introduction
A train may derail on the curved track due to the following defects in the track:
Improper super-elevation
Improper radius of curve
Improper speed

11. Gradient

12. Gradients
Provided to negotiate rise or fall

13. Gradients
Represented by distance travelled for a rise or fall

15. RULLING GRADIENT

17. Ruling Gradient Steepest gradient in a section
Determines maximum load hauled by a locomotive
Power of locomotive decided based on ruling
All other gradient in the section flatter than ruling

20. PUSHER OR HELPER GRADIENT

22. Pusher or Helper Gradient
Hilly areas gradient steeper than ruling
Extra locomotive required to pull entire load
Called as pusher or helper gradient
E.g. Budni – Barkhera section (CR)

26. Momentum GRADIENT

28. Momentum Gradient Steeper than ruling
Falling gradient followed by rising gradient
Falling gradient acquires good speed
No obstacles in the form of signals

30. GRADIENT @ Station Yards

32. SY
Prevent standing vehicle rolling from yard due to gravity/strong wind
Reduce additional friction require to start locomotive
Max. 1 in 400, recommended 1 in 1000 in IR

34. Grade Compensation

35. Grade Compensation Curve provide extra resistance
Grade reduced at curves
BG 0.04% per degree
MG 0.03%
NG 0.02% per degree

36. Causes for Rail Accidents in India

37. Many a times accidents occur on bridges during rainy season.
The reason is no regular inspection of bridges and tracks.
More over some of the bridges are very old and unable to carry fast speed trains or a even normal train.
The Rajdhani and Shatabdi are high sped trains in India which have been designed to travel with the speed of 160 kmph. 
But quality of tracks is not good to bear such a high speed in India.