CHARMEC. Railway accidents. should they be avoided? Anders Ekberg CHARMEC / Applied Mechanics

Transkript

1 CHARMEC Railway accidents should they be avoided? Anders Ekberg CHARMEC / Applied Mechanics anders.ekberg@chalmers.se

2 The current status

3 Railway safety performance in the European Union 2011 Rail fatalities Figure 1: Number of fatalities for different categories of railway user ( ) Passengers Employees Level-crossing users Unauthorised persons Others

4 Sweden 2008 SIKA Rail and road fatalities Total number of causualities Road: 3422 drivers and passengers in (car, truck, bus) Rail: 4 passengers Railway traffic about 10% of person kilometers About 100 times safer per person kilometer

5 Expected and unexpected consequences of accidents

6 Expected consequences Economical effects primary vs secondary who is paying? Long-term effects Swedish winters trust in rail Improvements Improved reliability through improved technology Traffic congestions

7 More unexpected consequences Legal effects Eschede lid on development Environmental effects Emissions from shift to road + maintenance actions + leakage etc Safety effects Eschede worst railway accident in Europe in modern time

8 Train accidents > road deaths Eschede train accident 101 fatalities German roads fatalities Increased road traffic by 2% from regulations is plausibe more secondary fatalities on road!

9 Some conclusions so far Travel by rail is generally much safer than road traffic Good safety reasons to shift traffic to rail (in addition to other factors) For this reason also non-fatal accidents are crucial since they cause disturbances and lack of trus in train travel

10 Derailments major failures

11 EU-project D-Rail Main causes of derailments 1. axle ruptures axle break 2. excessive track width 3. wheel failure 4. skew loading 5. excessive track twist 6. track height/cant failure 7. rail failures 8. spring & suspension failure Complications with clustering!

12 EU-project D-Rail The problem with statistics Reported freight derailments and average costs : France k Austria k UK k Germany k Switzerland k Large influence of reporting thresholds!

13 Eschede wheel break nbv.atw.hu

14 Hatfield rail break More than 2000 potentially dangerous sites were found in UK after the derailment

15 Brétigny-sur-Orge crossing Picture SNCF

16 Picture SNCF Brétigny-sur-Orge

17 Brétigny-sur-Orge Picture BEA-TT Bureau d enquêtes sur les accidents de transport terrestre

18 Södra station axle break Picture Trafikverket Broken axle Stockholm Södra Ultra sonic inspection Foto visar hjulets lutning i förhållande till växellådan.

19 Haninge likely rail break in S&C Picture Seko, Stockholm

20 Norra stambanan rail break Picture Anders Eriksson/Strukton Rail/Scanpix

21 Grötingen bearing box

22 What to do?

23 1 Paradigm shift Traditional approach static infrastructure re-action fixed maintenance intervals New situation rolling process industry pro-action condition monitoring and forecasting

24 Catch damage early! Increased load Increases deterioration Lennart Lundfeldt, Banverket Unwanted results

25 Exponential life decrease Wöhler around 1850

26 A typical consequence Kalousek, J, E Magel, J Strasser, W N Caldwell, G Kanevsky, and Blevins B (1996) Tribological interrelationship of seasonal fluctuations of freight car wheel wear, contact fatigue shelling and composition brakeshoe consumption. Wear 191, winter peaks

27 Reality behind statistics Needs for reprofilings Example of direct cost: ~50 Mkr for one line and one season

28 2 Monitor

29 3 Maintain Iman Arasteh khouy, Håkan Schunnesson, Ulla Juntti, Arne Nissen and Per-Olof Larsson-Kråik, LTU

30 4 Precise limits Stop only derailment prone trains

31 Challenges

32 The scatter is massive

33 The margins are slim Per Gustafsson

34 Optimisation and sensitivity

35 Some final remarks

36 Railway are safe for passengers Major failures should be avoided for overall societal safety etc Solutions that limit rail operations are sub-optimized The railway network needs to be seen as a process industry Risk management low probability / potentially major effects

37 Deal with outliers, but do not disrupt operations Optimize, but be aware of that this increases the sensitivity to disturbances Keep deterioration levels sufficiently low and under control the rest will follow

38 Many thanks for your kind attention!