Selection of Alignment & importance of track drainage

1. DEPARTMENT OF CIVIL
ENGINEERING
Factors Affecting Selection of an Alignment
Importance Of Track Drainage
Er. Ramprasad Kumawat
(M.Tech)

3. Factors Affecting Selection of an
Alignment
• 1. Gauge of railway
• 2. Obligatory or control points
• 3. Topography
• 4. Geometric standards
• 5. Geological considerations

4. • 6. Flood and climate
• 7. Roads and crossings
• 8. Labor and material
• 9. Station and yards
• 10.Economic
• 11.Politica

5. 1. Gauge of railway
• – Dictates permissible curvature
• Gauge = Clear distance between inner faces of
two track rails
• Broad gauge: 1.524m- 1.676m (5’ 0’’ -5’ 6”)
• Standard gauge: 1.435m-1.451m (4’ 8.5’’ -4’
9.125”)
• Meter gauge: 1m- 1.067m (3’ 3.375’’ -3’ 6”)
• Narrow gauge: 0.610m-0.762m (2’ 0’’ -2’ 6”)

6. 2. Obligatory or control points
• – Important cities and towns (intercity),
important growth centers (urban)
• – Major bridges
• – Existing passes or saddles
• – Avoid: monuments, religious buildings

7. 3. Topography
• – Plane
• – Valley
• – Mountain Zigzag Switch back Spiral

8. 4. Geometric standards
• – Gradients and curves

9. 5. Geological considerations
• – Stable soil

10. 6. Flood and climate
• – Sandy/snowy: Away from wind direction

11. 7. Roads and crossings
• – Right angle

12. 8. Labor and material

13. 9. Station and yards

14. 10.Political
• – Away from borders

15. 11. Economic
• – Construction, Operation, Maintenance
• – Maximize annual return= (R-E)/I
• R= revenue, E=expenses, I =Investment

18. IMPORTANCE OF TRACK
DRAINAGE
• Drainage of track is the most important factor
for the proper maintenance of track.
• Water softens the formation unless it is drained
away as soon as it falls on the track.
• Soft formation has less bearing capacity and is
liable to settle under load, seriously affecting
the track parameters as well as retentively of
packing.

19. • Interpenetration of soil and ballast takes place
in a soft formation causing loss of ballast into
the formation on the one hand and mud
pumping and clogging of ballast on the other.
• Loss of ballast on account of poor drainage can
be quite substantial.
• Ballast pockets inside the embankment collect
water and further soften the soil of the bank.
• Clogging of ballast affects drainage of water
on to the formation to be led in to the side
drains.

20. • It also affects the elasticity of the track which
means more wear and tear of track components
and vehicle under gear, resulting in rail
fracture, spring breakages and premature
renewal of track and vehicle components.

21. GOOD DRAINAGE OF TRACK
• It can be ensured by
• (i) Maintenance of clean ballast which will
drain the water quickly on to the formation.
• (ii) Maintenance of proper slope of formation
so that the water brought on to the formation
flows out of the track easily and quickly.
• (iii) Proper drainage arrangements so that
water does not stand near the track and flows
away from the track readily

22. • 2 Drainage of track on embankments takes
place as long as the less level is maintained
and the ballast is clean.
• The Permanent Way staff shall keep all side
drains and catch water drains clear as part of
annual maintenance not only on run through
lines but also on non running lines in yards

23. • THANKS!
Gmail:-
ramkumawat001@gmail.com