22/06/2012. LCC of Track. Peter Veit

Transcription

1 22/06/2012 LCC of Track The best track is the cheapest Peter Veit

2 Graz, Austria University of Technology Quality Behaviour Cost Driver High Quality Strategies Investment Under Sleeper Pads Asphalt Layer Frame Sleeper Maintenance Integrated t Maintenance

3 System Railways requirement: high speed 1 hour world record timetable Tokyo Osaka V = 230 km/h 300 km/h high speeds lead to low fault tolerances and thus high demand of maintenance availability? maintainability? SNCF 1955: 331 km/h requirement basically fulfilled

4 System Railways Austria - Europe availability? maintainability? mixed traffic requires high track accuracy for passenger trains but faces track deterioration due to dense freight traffic Austria: core network 6,000 km, total network 10,000 km 7,500 trains per day, 50% freight trains some double track sections have 320 trains a day

5 Requirements and Problems common problems: availability, maintainability solution: SUSTAINABILITY technically ca AND economically o ca quality behaviour life cycle costing (LCC)

6 22/06/2012 Quality behaviour

7 Track Quality Behaviour A good track behaves well, a poor one deteriorates faster. approach of research of cost-structures rate of degradation depends on actual quality level approach of research of quality behaviour Q(t) Q 0 e b t costs of operational hindrances investment + maintenance = LCC

8 Track Quality Behaviour Q(t) Q 0 e b t investment + maintenance Thus neglected maintenance From the point of view of life cycle costing there are new definitions for investment and maintenance: devaluates the investment done! Investment t delivers just initial iti quality, not service life. Maintenance transforms this initial quality into service life.

9 Track Quality Behaviour Technical Evaluation measured data since 2000 data of 3,800 km of main track: type and age of track and com- ponents, all recording car data, maintenance executed, transport data and alignment Regression analyses based on MDZ-A value or standard deviation every 5 meters time quality figu ure track work Q(t) = Q e bn t n

10 Track Quality Behaviour rolling stock transport volume alignment sleeper ballast rail sub layer sub grade drainage

11 Life Cycle Costing standard elements life cycle costs investment and maintenance strategy transport load sub soil sleeper profile steel grade R > 3000 m > gross/day, track good concrete 60E1 260 double track track work track laying 1$ levelling-lining-tamping 1$ 1$ 1$ 1$ 1$ 1$ 1$ 1$ 1$ 1$ grinding 1$ 1$ 1$ 1$ 1$ rail exchange sleeper exchange exchange of rail pads joint maintenance small maintenance 05 0,5 $ 05 0,5 $ 05 0,5 $ 05 0,5 $ 05 0,5 $ 05 0,5 $ 05 0,5 $ 05 0,5 $ 05 0,5 $ 10 1,0 $ 10 1,0 $ 10 1,0 $ 10 1,0 $ 10 1,0 $ 10 1,0 $ 10 1,0 $ 10 1,0 $ 10 1,0 $ 15 1,5 $ 15 1,5 $ 15 1,5 $ 15 1,5 $ 15 1,5 $ 15 1,5 $ 15 1,5 $ 15 1,5 $ total costs Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ Σ dynamic costs evaluation principle (3% net rate of interest): minimum of dynamic average annual costs including costs of operational hindrances

12 Track Quality Behaviour

13 Lessons Learnt time de ecreasing tra ack quality threshold value The better the initial quality the less the maintenance demand.

14 Lessons Learnt time de ecreasing tra ack quality adequate maintenance fights causes threshold value inadequate maintenance fights symptoms Just maintenance solving problems is sustainable.

15 Reality in Track Looking homogeneous sections of one parameter set should result in the same track behaviour. time decreasing track quality ynormal variation? Nothing special - just a drainage problem.

16 22/06//2012 Cost Driver

17 Cost Driver in Track 1:9 1. Initial track quality precondition: subsoil quality and functionality of drainage

18 Poor Sub-Soil or Drainage Caused by insufficient subsoil strength.. or by inefficient drainage for a couple of years IRR of additional investment for inserting a protection layer up to 35% (!)

19 Poor Sub-Soil or Drainage

20 Cost Driver in Track 1:9 1. Initial track quality precondition: subsoil quality and functionality of drainage 2. Switch density 1 EW500 ~ 450 m track 3. Ballast Quality If subsoil quality and/or drainage demands do not meet the requirements optimisation of track is not possible.

21 Ballast Quality Service Life of Track Comparing service lives of track and turnouts demonstrate the high importance of ballast quality, ballast strength as well as sieve curve. track service lives compared track turnout ballast ÖBB 100% 100% LA 22 SBB 110% 110% LA 17 HŽ 80% 65% weak limestone

22 Cost Driver in Track 1:9 1. Initial track quality precondition: subsoil quality and functionality of drainage 2. Switch density 3. Ballast Quality 1 EW500 ~ 450 m track 4. Radii 1:3 up to 5. Cost of operational hindrances 30% 6. Length of track work section 7. Traffic density under linear up to 20% 8. Quality of rolling stock ± 10% 9. and of course high speed, mixed traffic, and axle load

23 Implementing Less Quality Economic Evaluations Components The examples presented for different variations are calculated for high performance track sections (~ gross tons per day and track). The costs of the base case (static evaluation) arise from optimised strategies using standard components and thus depict the best case for standard components. Re-Inve estment Costs of Base Case g example: 54E2 rails instead of 60E1 immediate savings versus long term additional costs = 1 : 25 Annual Average Costs Depreciation Costs of Operational Hindrances Maintenance Costs

24 Neglecting necessary Sub-Soil Rehabilitation Costs of Base Case* stment Re-Inves poor sub-soil soil immediate savings versus long term additional costs = 1 : 23 * Costs of Base Case including Sub-Soil Rehabilitation

25 Reducing Maintenance stment Re-Inves Costs of Base Case stretching tamping cycles stretching tamping cycles immediate savings versus long term additional costs = 1 : 4

26 Characteristic of Track Reality Model Photo: Franz Piereder Track is patient, patient not reacting immediately if treated insufficiently insufficiently. Track has got a remarkable memory. It remembers insufficient support. Whenever track reacts, service life is already gone. We can t change the characteristics of the elephant, we need to react on it. Yes, we can save a lot of money not executing sufficient maintenance Yes maintenance. However, when the elephant doesn t feel well it s already too late

27 22/06//2012 High Quality Strategies High Quality Strategies Examples

28 High Quality Strategies Obviously just high quality track strategies can form a stable and thus cheap track. INVESTMENT Under Sleeper Pads Asphalt Layer Frame Sleeper MAINTENANCE Integrated Maintenance Design Tamping

29 Under Sleeper Pads

30 Under Sleeper Pads contact areas sleeper - ballast after tamping 9% after tamping and stabilizing with Under Sleeper Pads (USP) up to 35% 3% to 5% before after tamping up tamping to max. 12%

31 Under Sleeper Pads track behaviour reference track: 60E1 rails CW on concrete mono bloc sleepers 60E1 rails CW on concrete mono bloc sleepers with USP initial q alit increased b 18% initial quality increased by 18% b-rate reduced by 63% prolongation of tamping cycle by the factor of 2.75 service life + 38%

32 Under Sleeper Pads Track Turnout 140% Average Gesamt Annual LCC Costs 120% Depreciation Abschreibung 100% 80% 60% 100% 100% Costs Betriebserschwerniskosten of Operational Hindrances Costs of Maintenance Instandhaltung 68% 68% 100% 100% 79-82% 82% 40% 20% 0% reference Basis 2007 with USP reference Basis 2007 Schwellenbesohlung with USP additional investment in initial quality pays back IRR 12 per cent to 15 per cent

33 Under Sleeper Pads Track Behaviour without t USP red line: tamping, green line: grinding 1 km σ v =2mm (1 km) TGV: high spee ed line 320 km/h years today

34 Under Sleeper Pads Track Behaviour without USP with USP intervention level: σ v = 1.3 mm (1 km) intervention level: σ v = 0.6 mm (1 km)

35 Asphalt Layer Built in in Switzerland since late 1930ies mainly in station areas Quality - Time - Diagram TIME in Years QUALITY in MDZ-a red line: with asphalt layer ÖBB maintenance free asphalt layer built in 1963

36 Asphalt Layer Present Status t Observation of sections with asphalt layer show a better track behaviour. Thus asphalt layer (thickness ~ 8 cm) are part of the standard superstructure for new lines targeting for the entire service life 1 2 1* of track: 2 1 a clear separation between substructure and superstructure 1 avoiding pumping effects guaranteeing draining of water and thus avoiding plants growing up However, the asphalt layer should not be too stiff, I order to avoid cracking of ballast. Thus in Austria USP are used together with the asphalt layer.

37 Asphalt Layer Consequently asphalt layers of 8 cm to 12 cm thickness form a standard for new high capacity and high speed lines in Austria. picture a to c: Koralm link (under construction), picture d: Schoberpass-line, built in 1991

38 Frame Sleeper

39 Frame Sleeper 2 LLT (conventional track only) stan ndard deviat tion vertical [mm] 1 relaying Q 0 = 0,46 b = 0,201 conventional track Q 0 = 0,56 b = 0,271 frame sleeper track Q 0 = 0,38 b = 0, time [years] 2007 traffic load: /day Standard deviation vertical 0,4 0,6 mm within 8 years

40 Frame Sleeper insulating joint strengthened by one single Frame Sleeper (Denmark, Netherlands)

41 Resulting Track Strategy Until HT rails were just used to reduce side-wear of rails and thus installed in radii less than 500 m, only Since 2010 due to RCF 350HT rails are installed in radii up to 3000 m, depending on the traffic load, more and more grinding is executed (not just new rails or rails in small radii as before) USP is standard for main line track with concrete sleepers and train speeds above 160 km/h or radii less than 600 m and whenever track is equipped with USP turnouts with under sleeper pads are installed Slab track is used in tunnels only Next steps to go: implementation of dog bone sleepers for critical sections and frame sleepers for supporting insulated joints 1 (and the most critical sections) 1 However, in general in Europe axle counters are installed instead of insulated joints (except on TGV lines of SNCF)

42 Integrated Maintenance Track Behaviour (SNCF) without USP with USP Best improvement of track quality, whenever levelling-lining-tamping (LLT) is combined with grinding or grinding is executed close after LLT

43 Integrated Maintenance Quality Behaviour rtical eviation ve LLT only integrated maintenance standard d 0.6 mm 0.4 mm 0.2 mm year

44 Integrated Maintenance Tamping Strategy t at ÖBB since 2010 single failure track and turnout integrated tamping tamping maintenance safety urgent single failures per year quality 2 years planning 900 km track and turnouts preventive main lines 8 years planning 150 km track 100 Stk. turnouts 10% 75% 15% of tamping budget of tamping budget of tamping budget

45 Design-Tamping tamping in 2005 Track remembers 30% over-lifting its failures of vertical or: track failures failures have reasons just to increases time until failure must be repaired again

46 22/06//2012 Summary

47 Stable and cheap ballasted track is possible, if following quality strategies. However, there are preconditions to be fulfilled within (re-)investment: - good sub soil or insertion of sub layer - drainage, drainage, drainage (as we already know) - good ballast quality and all that must be maintained properly.

48 Thank you! Peter Veit Phone: