1. CE 515 Railroad Engineering
Track
Source: Armstrong Ch 3, AREMA Ch. 3, REES Module 2
“Transportation exists to conquer space and time -”

2. Track Alignment How is Alignment Measured in Tangent Track?
Show example on board

3. Track Alignment How is Alignment Measured in Curved Track?
Mid-Ordinate Offset (in)=Degree of Curvature

4. Horizontal Curve Elements

5. Horizontal Curve Elements

6. Horizontal Curve Elements

7. Gage
Measuring Gage
Measured 5/8” down from top of rail, 56-½” between

8. Gage Max Gage allowance 1-3/4” wider Class 4 Operation, 1” max
Class 4: Freight 60mph, passenger 80mph

9. Turnouts 3 Groups of Turnouts Lateral Turnouts Equilateral Turnouts
Lap Turnouts

10. Turnouts Yard on south end of Chicago Loop
Note the different types of turnouts and crossovers present
Bingmaps.com

11. Turnout Terminology
Also See AREMA pp
Fig 3-13 from Armstrong

12. The Switch
Device deflecting wheels of train from track they are running
Switch is portion of turnout from Point of Switch (PS) to Heel of Switch (HS)
Video (model):

13. The Switching Mechanism
Hand operated (switch stand)
Power operated (machine)

14. Frog Permits flange of wheel to cross the other rail

15. Frog Types Rail Bound Manganese (RBM) Spring Frog
Solid Manganese Self-guarded Frog
Bolted Rigid Frogs
Movable Point Frogs

16. Guard Rails

17. Railway Crossovers and Crossings
Crossovers can be considered as two turnouts
Crossing consists of 4 frogs (2 intersecting tracks)

18. Railway Crossovers and Crossings
Slip Switch: combination of small angle crossing with pair of connecting tracks within limits of crossing

19. Railway Crossovers and Crossings
Information needed to design crossings
See AREMA pp
Specialty manufactures design these features
Train Crossing Frog:
How they work:

20. Highway Crossings Renewal of Crossings are Expensive
Public Safety is Serious Concern

21. Highway Crossings