Maintenance - the key driver of railway infrastructure costs Stasha Jovanovic, Ph.D. Faculty of Technical Sciences, Novi Sad, Serbia Euro Rail Consult, Belgrade, Serbia 1
Level of Influence SEETO Transport Infrastructure Forum, Transport: A driver of growth, Sarajevo, March 22, 2016 Cumulative Total Cost Importance of maintenance 100% 100% 50% 50% 0% 0% Planning Design Construction Maintenance 5 Time (Years) 50-100 1 20 2
Costs of Track maintenance Manual maintenance 20 % Renewal 70 % TOTAL MAINTENANCE AND RENEWAL COST on Dutch Railway network (ProRail) 250 million per year for 4.500 km track Price level 2006 Mechanical Maintenance 10 % Average in Western Europe: 50,000 EUR/km/year on conventional lines
Track Deterioration Vicious Circle Plastic behavior of ballast Ineffectiveness and decreased Durability of Tamping MAIN CULPRITS Ballast crushing (creation of fines ) Tamping Short-wave irregularities FORCES Long-wave track irregularities Rail Damage Sleeper Damage Substructure Damage 4
Track Loads Wavelength Frequency f [m] Forces Passenger comfort QI s from Track recording cars 5
M&R Costs Estimation Model ORE/ERRI D141 & D161.1 Research Projects Deterioration Law, which is characteristic for every element and every type of a track structure, depends on the traffic characteristics, among which especially: Dynamic axle loads, speed, accumulated traffic load, and uncompensated lateral acceleration, curve radii, vehicle types, etc. e( T ) e 0 k T P V Where: T Accumulated Traffic Load P Representative Dynamic Axle Load (P = SQ) V - Speed
M&R Costs Estimation Model ORE/ERRI D141 & D161.1 Research Projects This model is especially useful/adequate for economical calculations of RELATIVE changes in costs, where the value of new Costs (C 2 ) can be expressed in relation to the old Costs (C 1 ) via the following formula [1]: C C 2 1 P 2 P 1 1 V V 2 1 e e max 1 max 2 e e 01 02 Where: P 2 & V 2, etc., represent new values, and P 1 & V 1 old values.
M&R Costs Estimation Model ORE/ERRI D141 & D161.1 Research Projects Assuming ALL other conditions to be THE SAME, i.e. P 2 = P 1 and V 2 = V 1, we get: C C 2 1 P 2 P 1 1 1 1 V V 2 1 e e max 1 max 2 e e 01 02 C 1 emax1 e01 2 1 C emax 2 e02
Relative cost increase [%] C C M&R Costs Estimation Model ORE/ERRI D141 & D161.1 Research Projects Total Benefit (cost saving): C C C { RailFatigu e} { RailSurface } { OtherComponents } { TrackGeome try} 800 SEETO Transport Infrastructure Forum, Transport: A driver of growth, Sarajevo, March 22, 2016 Relative cost increase as the consequence of track quality decrease 700 600 500 400 Cost Difference (track geometry) [%] Cost Difference (rail fatigue defects) [%] Cost Difference (rail surface defects) [%] Cost Difference (other track material, excluding rails) [%] Total Cost Difference (Annual) [%] 300 200 135% 100 0 135% cost increase = 2.35 times the original cost! 10 20 30 40 50 60 70 80 Increase of track geometry deviations i.e. decrease in track quality [%]
Strictness of Track Geometry Thresholds: Speed [km/h] Vertical Track Geometry (D1) Standard Deviation Thresholds [mm] Track Quality Classes A B C D E V < 80 < 1.25 1.75 2.75 3.75 > 3.75 80 < V 120 < 0.75 1.10 1.80 2.50 > 2.50 120 < V 160 < 0.65 0.85 1.40 1.85 > 1.85 160 < V 230 < 0.60 0.75 1.15 1.60 > 1.60 230 < V 300 < 0.40 0.55 0.85 1.15 > 1.15 V > 300 N/A N/A N/A N/A N/A The scatter in deterioration rate values is between 1 and 10 mm SD / 100 MGT, and largely depends on exerted dynamic forces. Typical improvement rate achieved by Tamping machines is about 30%.
Influence of track geometry quality Q [kn] (97.5 %-value) 150 Moderate s > 2 mm SQ [kn] (97.5 %-value Good 1 < s < 2 mm 50 125 Freight wagons with 22.5t axle load Very good track geometry quality s < 1 mm 40 30 20 110 km/h 90 km/h 70 90 110 V [km/h] 10 70 km/h Axle load 0 Track Geometry Quality 20 t 20 t 20 t 22.5 t 22.5 t 22.5 t Very good Good Moderate Axle load
Influence of rail welds quality Q Q = Dynamic amplification 6 Dynamic amplification Q-force 6 P 1 force 5 4 5 4 P 2 force 3 2 3 1 Speed speed V [km/h] 2 0 20 40 60 80 100 120 1 0 Timetime t [ms] 2 4 6 8 10 12 14 16 18 20 22
Influence of wheel quality Force [kn] 160 140 120 100 80 60 40 V = 35 km/h Wheel flat: 100 mm long 1.5 mm deep Impact of wheel flat on force between rail and sleeper Wheel-flat load Nominal load Q [kn] Effect of wheel flats on wheel load 20 0-20 Time t [s] 0.02 0.04 0.06 0.08 0.10 0.12 0.14 0.16 350 300 250 Axle load: 22.5 t Speed: 30 km/h a < 25 g Concrete sleeper Wooden sleeper 200 150 100 50 kn/mm 30 kn/mm UIC limit: 0.9-1.4 mm Wheel flat depth [mm] 0 1.0 1.6 2.8 4.3 6.3
Total lifetime extension (extra to ref. lifetime) (%) SEETO Transport Infrastructure Forum, Transport: A driver of growth, Sarajevo, March 22, 2016 Why is weld quality so important? Lifetime Lifetime 700 new orig. 3 Forig. ; F F F Fnew wheel wheel, stat wheel, dyn 600 500 400 300 200 100 0 0 10 20 30 40 50 60 Total load reduction (%)
Expected Cost Savings Due to impact load reduction at welds: 10 20 % of annual maintenance budget; ProRail budget in The Netherlands: ~ 250 mio for 4,500 single track; Savings: 25 50 mio total, or 5 10,000 per km of single track every year. Manual maintenance 20 % Renewal 70 % Mechanical Maintenance 10 % TOTAL MAINTENANCE AND RENEWAL COST ON NS 250 million per year for 4.500 km track Price level 2006
Tonnage borne on Dutch Railways 1988 % per 20 MGT 30 20 10 UIC 54 CWR 100% 70% of ntwrk. NP 46 CWR 100% 30% of ntwrk. Ntwrk. 5,000km Rail Renewal 100 /m 3 unnecessary renewals 3 bil. Infraspeed contract ~ 750-900 MGT 25-30 years Tonnage [MGT] 0 50 100 150 200 250 300 350
Tonnage borne on AUS Heavy-Haul Rlwys As of 2010, the Rio Tinto Pilbara Iron network served 11 mines in the Pilbara region, transporting 220 million tonnes of iron ore to the ports at Dampier and Cape Lambert annually. Rio Tinto iron ore train consist of up to 236 wagons, each 106 tonnes; Trains are up to 2.4 kilometres (1.5 mi) long and weigh apprx 29,500 tonnes. Roy Hill 55 million tones of iron ore per annum. BHP Billiton Mount Newman railway in 2001 broke the world record for the heaviest train as well as the longest train when a train weighing 99,734 tons and formed of 682 wagons ran for 275 kilometres between Yandi and Port Hedland. The train was 7.3 kilometres long, carried 82,000 tons of iron ore and was hauled by eight GE AC6000CW locomotives. Annual operation up to 205 million tonnes. FMG (Fortescue Metal Group) railway currently undergoing an A$50m upgrade to facilitate an expanded railway network, with the capability of handling 155 million tonnes of iron ore per annum. In Jan 2012 a record 210,000 tonnes is railed in one day ( 70 MGT/y) Up to 2 billion tons (2,000 MGT)
Solution -> Increased focus on Maintenance A. Shift towards condition-based maintenance and renewal (M&R)management (Railway Asset Management Systems R-AMS) B. Mandatory inclusion of maintenance considerations into the regular design documentation (Maintenance Design)
What is Condition-based approach? Over the next two decades, medicine will change from its current reactive mode, in which doctors wait for people to get sick, to a mode that is far more preventive and rational. A vision of the future of maintenance What s driving this change are powerful new measurement technologies and the so-called systems approach to medicine. 19 The average doctor s office visit might involve blood work and a few measurements, such as blood pressure and temperature; in the near future physicians will collect billions of bytes of information about each individual genes, blood proteins, cells and historical data.
Condition-based M&R Management FROM: Diagnostic data used mostly for the controlling purposes TO: Diagnostic data used as the driver for maintenance activities Planned preventive maintenance Corrective maintenance Survey activities Today Tomorrow M&R Costs
Condition-based M&R Management (R-AMS) Reduction / minimization of Accidents (e.g. derailments) Taking Control of Dynamic forces => extension of asset service lives Shifting from Corrective to Preventive Maintenance, i.e. acting BEFORE defects have occurred Reducing defects/damages Minimizing Traffic Disturbances & Speed Reductions Allowing time for Planning and Resource Allocation Optimization Enabling What-if analysis, i.e. the ability to test different Maintenance Management Policies & Strategies
R-AMS Basic Data Groups Inventory Data Operating Data Condition Measurements Work History Map data Speeds Track Geometry M&R Works Track Layout Annual Loads Rail geometry Type Curves Transitions Slopes Superelev. Objects Inventory Objects Location Objects Characteristics Types Installation Dates Axle Loads Costs Line Categories Corrugation Wheel/Rail forces Ride comfort Ultrasonic measurements Rail Surface Defects Ballast % of fines Geotech/Petrogr. anal. of ballast Sleeper cracking and/or clustering Various (visual) inspection data Date Location Costs Inspections Other interventions
Integrated Condition Measurement Track Monitoring Track Geometry Rail Profile Rail Corrugation Overhead Line Monitoring Overhead Line Geometry (static and dynamic) Contact Wires Wear Catenary/Pantograph Interaction Electrical Arcs Electrical Parameters (Voltage and Tension) Ride Quality Instrumented wheels for Wheel/rail interaction forces Body and axle-boxes accelerations Wheel-Rail Contact Geometry Vehicle-Track interaction Ultrasonic inspections Rails, Welds, Wheels Telecommunication Monitoring GSM, GSM-R and ETACS monitoring Signaling Monitoring Monitoring of coded currents in the track Auxiliary Systems High Accuracy Positioning Systems (Encoders, Doppler radar, Transponders, Passive Milestones Laser Readers, Differential GPS) Video Inspection of Track, Wayside and Overhead Line Optical Fiber Communication Network
Typical measuring vehicle Operational Management Total length of lines to survey Survey Frequency Total amount of km covered in 1 year Average length surveyed in 1 working day About 10.000 km 1 week / 3 months 80.000 Km 500 km Acquired data in 1 month 1 Tb Need for a Railway Asset Management System (R-AMS)
Railway Asset Management Systems Text Report Graphical Linear Photos Vision Images/Videos GIS
Railway Asset Management Systems Deliverables - Benefits Optimal Work Plan (long, short and middle term) What-if analysis - ability to test different Resource Management Policies Estimation of Resource Requirements Estimation of Traffic Disturbances Optimal Resource Allocation Full Cost-breakdown & Cost/Budget Optimization While ensuring optimal assets condition at all times!
Mandatory inclusion of maintenance considerations into the regular design documentation (Maintenance Design) 1. Railway infrastructure condition-monitoring Programme a) Types of measuring systems to be used Automatic/production measuring systems (measuring vehicles) Hand-held (portable) measuring systems Track wayside measuring equipment b) Determination o the optimal frequency of measurement 2. Determination of the optimal: a) Condition-analysis concept (selection of a Railway Asset Management System) b) Track and rail geometry quality to be maintained, with respect to the dynamic forces and consequential deterioration of track and rail geometry, as well as of all track components c) Track Tamping regime d) Rail and Weld Grinding regime e) Wheel/Rail Interface characteristics f) Railway infrastructure Renewal regime, with respect to the established maintenance regime (optimal balance between maintenance & renewal) g) Switches & Crossings Maintenance & Renewal regime h) Thresholds for all key railway infrastructure condition parameters (track geometry, rail wear, rail corrugation, rail internal and surface defects, overhead line wire geometry and wear, civil structures, etc.) i) Routine maintenance regime