Presented by: Prof. Hannes Grabe at the 2009 Railways and Harbours Conference in Cape Town.

1. Track Deflection Measurement using Particle Image Velocimetry Hannes Gr äbe University of Pretoria Chair in Railway Engineering

2. Definition ? What is an Engineer Someone who knows how to measure !

4. Dynamic loading on non-rigid track deflection

5. Deflection measurement: Field tests

6. Deflection measurement: Lab testing

7. Deflection calculation: Analysis

8. Deflection measurement: Construction

9. Deflection measurement: Failures

11. Instrumentation ? What capabilities should instrumentation have Reliability 1. Optical 2. Mechanical 3. Hydraulic 4. Pneumatic 5. Electrical Simplicity Quality Cost!

12. Track loading & deflection Ballast Subballast Subgrade 1 Subgrade 2

13. Electrical: Multi-Depth Deflectometer

14. MDD Installation

15. Field Instrumentation MDD module Load plate Soil sampling

16. MDD Results Time

17. Electrical: LVDT* * Linear Variable Differential Transducer

18. Electrical: LVDT* * Linear Variable Differential Transducer

19. Electrical: LVDT* * Linear Variable Differential Transducer

20. Mechanical: Sleeper deflection meter* * Design: Sakkie van der Linde

21. Mechanical: Geometry car measurements

22. Mechanical: Geometry car measurements Versine measurement Gauge measurement

23. Optical: Manual and digital level

24. Optic deflection measurement Particle Image Velocimetry (PIV) For optical track deflection measurement

26. Transnet Freight Rail PIV system

27. Target fixed to the rail

28. Target fixed to the rail * 2cm x 2cm square target

29. PIV Calibration

30. PIV System: Resolution * Standard deviation: 0.003 – 0.005mm

31. Applications of PIV Amandelbult Centurion Ermelo

32. Amandelbult

33. Amandelbult

34. Amandelbult PIV tests

35. Amandelbult: resolution

36. Amandelbult test results 32km/h 7km/h

37. Amandelbult: Camera vibration

38. Centurion station

39. Centurion station measurements Conventional track Tubular track

40. Centurion measurements Tubular Track: Platform 2 (Rail & Beam deflection) -2.0 -1.5 -1.0 -0.5 0.0 0.5 0.0 2.0 4.0 6.0 8.0 10.0 12.0 Time (s) Deflection (mm) Rail Beam

41. Centurion measurements Tubular and Conventional Track Comparison -2.0 -1.5 -1.0 -0.5 0.0 0.5 0.0 2.0 4.0 6.0 8.0 10.0 12.0 Time (s) Deflection (mm) Tubular Conventional

42. Ermelo Yard

43. Eremlo Yard

44. Ermelo Yard PIV measurements

45. Ermelo Yard PIV measurements

46. Ermelo Yard PIV measurements

47. PIV measurements Ermelo: Rail , Beam , Grout , Formation Deflection -3.5 -3.0 -2.5 -2.0 -1.5 -1.0 -0.5 0.0 0.5 30 35 40 45 50 55 Time (s) Deflection (mm)

48. Tubular vs. Conventional turnout

49. Comparative analysis A: End-of-beam C: End-of-beam B: Mid-beam

50. End of beam deflection: Position B A B C

54. Questions… Thank you for your attention!