PhD-Work

1. PhD-Work DI Robert Hummitzsch Trondheim, Oktober 21st 2005

2. Long Term Track Quality Prediction of Long Term Deterioration for Economic Optimisation of Railway Infrastructure DI Robert Hummitzsch robert.hummitzsch@tugraz.at Trondheim, Oktober 21st 2005

3. Content of Presentation Definition of Track Quality Principle Aims and Basic Considerations of PhD-Thesis Topic to be Discussed in Workshop

4. Definition of Tack Quality DI Robert Hummitzsch robert.hummitzsch@tugraz.at Trondheim, Oktober 21st 2005

5. Definition of Track Quality Railway Tack… ...is understood as the entire sub- and superstructure. Namely the rails, railpeds, sleepers, fixings, ballast, formation and subgrade Track Quality… ...is the entirety of the quality of all these components and the accuracy of their arrangement within the track

6. Definition of Track Quality Effect of Track Quality on Railway Operation The linking point between infrastructure and operation is the rail surface geometry Track- (Rail-) geometry depends on track quality Track geometry effects the railway operation A certain track geometry at a certain operation speed leeds to a certain riding quality Riding Quality = Track Quality

7. Definition of Track Quality How to measure track quality? Track geometry is measured in various parameters: • Horizontal level • Vertical level • Gauge • Twist • Curvature • ... Threshold values for safety but Economically sensible values are higher Which of these parameters define this quality?  An integrated parameter is needed

8. Definition of Track Quality MDZ-Evaluation

9. Principle Aims and Basic Considerations of PhD-Thesis

10. Principle Aims of Thesis Identification of impacting parameters • Circumstances that lead to a special type of degradation function • E.g.: subsoil, traffic density, radius, age and type of components of super-structure, radii….. Prediction of degradation behavior • Between two tamping actions • Relative improvement by tamping • Over the whole lifetime

11. Principle Aims of Thesis Importance of Knowledge of the Degradation Function • Prediction of Residual Life Time • Depreciation • Time of next necessary investment • Prediction of Life Cycles • Which measures must be taken at what time • How often must a measure be taken in order to achieve a long life span --> Basic data for all LCC analysis

12. Principle Aims of Thesis Which is the right function Linear Functions less accuracy but simple 3) good accuracy Exponential Functions Best accuracy but rather complex

13. Principle Aims of Thesis Degradation Function 3)

14. 0 100 200 300 400 500 600 700 800 900 0 time -5 -10 -15 -20 -25 -30 MDZ-A Principle Aims of Thesis Degradation behavior between two tamping cycles Degradation Function Q = Q0e-bt Q0

15. 0 100 200 300 400 500 600 700 800 900 0 time -5 -10 Improvement by tamping -15 threshold value -20 -25 -30 MDZ-A Principle Aims of Thesis Relative Improvement by Tamping Degradation Function Q = Q0e-bt Q0

16. 0 time -5 -10 -15 -20 -25 economical service life -30 MDZ-A Principle Aims of Thesis Degradation over entire lifetime Global Degradation Function Q = Q0e-bt ??? Q0 threshold value

17. Principle Aims of Thesis Expected result of PhD-Work • The developed model should be able to • Predict the expected lifespan of a certain section of track with given circumstances • Create several possible maintenance scenarios --> Basis for economic comparative evaluation • Identify the cost-driving circumstances of any track section

18. Principle Aims of Thesis Basis and procedure of research • Existing findings on degradation behaviour realised at the institute • State new theories on Austrian track data By mathematic-statistical analysis of the data • Verify all findings with Norwegian track data • Results are further treated only if valid both for Austrian and Norwegian data

19. Topic to be Discussed in Workshop

20. Topic to be discussed Influence of Subsoil Subsoil is supposed to be the most impacting parameter on geometrical degradation of track So far no explicit measurement of subsoil quality is possible. It depends on traffic caused dynamic influences. • Is it possible to define an explicit quality figure for substructure? • Is there a way to determine the influence without knowing explicit figures?

21. Topic to be discussed Quality of Track • Are our assumptions correct? • Could it be defined in another way? • How could it be measured if defined different?

22. Thank you for your attention…