Research and Development on Ballasted Track in Japan

Transcription

1 Research and Development on Ballasted Track in Japan Hideyuki TAKAI

2 Contents 1. Outline of RTRI 2. Ballasted track and Slab Track 3. R&D on Ballasted Track at RTRI 4. For the Future of Ballasted Track 5. Conclusions 2/37

3 (RTRI) Dec.1986 Incorporated (Nonprofit) Apr Takeover R&D of Japanese National Railways (JNR) Japan Rail (JR) group 3/37

4 Bird's-Eye View of RTRI Personnel : 530 (170 PhDs ) Budget : 135 Million EURO Patents : 2,100 4/37

5 Organization of RTRI Board of Trustees Board of Directors Chairman President Auditors Executive Directors Track Technology Division Planning - Track Structures Division & Components Lab. - Track Structures & Geotechnology Lab. Compliance Division - Track Geometry & Maintenance Lab. Administration - Rail Welding Division Lab. Accounting Division Information Management Division International Affairs Division R&D Promotion Division Marketing & Business Development Div. Railway Technology Promotion Center Railway Dynamics Division Railway - Track International Dynamics Lab. Standards Center Vice Presidents 12 Research Divisions Vehicle Structure Technology Division Vehicle Control Technology Division Structures Technology Division Power Supply Technology Division Track Technology Division Disaster Prevention Technology Division Signalling & Transport Information Tech. Div. Materials Technology Division Railway Dynamics Division Environmental Engineering Division Human Science Division Maglev Systems Technology Division 5/37

6 Contents 1. Outline of RTRI 2. Ballasted track and Slab Track 3. R&D on Ballasted Track at RTRI 4. For the Future of Ballasted Track 5. Conclusions 6/37

7 Railway Network in Japan 2,620 km 780 km Hokkaido Japanese National Railways (JNR) JR 7 Companies 6 Passenger and 1 Freight Freight Approx. 20,000 km Kyushu West Shikoku Central East Other 197 Companies 189 Passenger and 8 Freight Approx. 7,000 km 7/37

8 Infrastructure of Shinkansen Lines Earth Bridge Viaduct Tunnel Tokaido 東海道 Sanyo-east 山陽東 Sanyo-west 山陽西 Tohoku 東北 Jyoetsu 上越 Hokuriku 北陸 Kyushu 九州 0% 20% 40% 60% 80% 100% 8/37

9 Track structure of Shinkansen Lines Ballasted Slab Tokaido 東海道 Sanyo-east 山陽東 Sanyo-west 山陽西 Tohoku 東北 Jyoetsu 上越 Hokuriku 北陸 Kyushu 九州 0% 20% 40% 60% 80% 100% 9/37

10 Maintenance cost (M-Yen/Year/km) Comparison of Maintenance Costs In case of Sanyo shinkansen Ballasted track Costs 1/4 Slab track Others Fastenings CA-mortar Alignment Leveling Overall leveling Year 10/37

11 Total cost Study about Life Cycle Cost (LCC) The construction cost of slab track is 30 % higher than that of ballasted track. But daily maintenance cost is one forth, then the total cost balances after 9 years after construction. 30% higher Balances after 9 years Ballasted track Slab track Maintenance cost Construction cost Year after construction 11/37

12 Comparison of Performance Items Ballasted Slab 1. Construction cost Good Poor 2. Construction speed Even Even 3. Construction precision Even Even 4. Durability (Maintenance) Poor Good 5. Vibration & noise Good Poor 6. Track buckling Poor Good 7. Ballast-flying Poor Good Other advantages of slab track - Lighter weight reduce dead load of viaducts. - Lower height reduce cross-section area of tunnels. 12/37

13 How to Choose Track Structure? Slab track or other type of non-ballasted track is chosen for newly constructing railway line in Japan. However, ballasted tracks are still used in following cases. Train load is small enough. (Light weight, Low speed, Low frequency) Lowering vibration and noise is requested. Roadbed subsidence will be expected. Change of track layout will be expected. Although, almost all railways are ballasted track, and they will be used for a considerably long period. Then, RTRI set great effort to improve ballasted track. 13/37

14 Contents 1. Outline of RTRI 2. Ballasted track and Slab Track 3. R&D on Ballasted Track at RTRI 4. For the Future of Ballasted Track 5. Conclusions 14/37

15 R&D on Ballasted Track at RTRI Outline of research and development projects relating to ballasted track, those are conducted at RTRI. Roadbed Improvement method by grout filling Automatically irregularity correcting sleeper "AICS" Optimization of track maintenance planning Safety evaluation of coseismic track buckling Ballast-flying and its countermeasures 15/37

16 Roadbed Improvement Method by Grout Filling Mud pumping is serious problem of ballasted track on clayey and poorly-drained soil. Typical mud pumping This method build up stable layer under ballast using existing ballast and quickly hardening grout. Soft roadbed Waterbearing layer Stable layer 16/37

17 Construction Process 1. Before Improvement 2. Excavation of ballast and roadbed 3. Preparation of grouting materials Fluid-A Fluid-B 4. Casting existing ballast 5. Grouting 6. Rebuilding ballast bed - No need of compaction of the original ground - Reduction of industrial waste and construction time 17/37

18 Longitudinal 高低変位 (mm) level (mm) Field Test on Operating Line Before After Improved area months 6ヵ月後 later 11 11months ヵ月後 later Before 未対策 improvement Place 位置 (m) 18/37

19 Automatically Irregularity Correcting Sleeper "AICS" "AICS" automatically correct track irregularity, by the falling action of steel balls inside. This device is functional for the place of, Rail joint Boundary area between ballasted and fixed track AICS Insulation plate 19/37

20 Working Principal of "AICS" Load 荷重 レRail ール Steel 鉄球 balls バラ スト Ballast 絶縁板 Insulation plate Inner 内筒 cylinder Outer 外筒 cylinder 隙間に Fallen 粒状体が balls 落下 沈下 Subsidence Load 荷重 隙間を 埋めた Fallen balls 粒状体が荷重を 伝達 support load 20/37

21 Comparison of Lording Test Without AICS kn axle load - After 1 million times Evident loose sleeper With AICS kn axle load - After 2 million times Modest oscillation under heavy axle load 21/37

22 Irregularity Irregularity Optimization of Maintenance Planning Cumulative maintenance cost Choice of maintenance works to minimize Life Cycle Cost (LCC) Tamping Appropriate ballast renewal decrease LCC Period becomes shorter Tamping Ballast renewal With ballast renewal Without ballast renewal Period gets longer Time 22/37

23 Flow of Decision Making of Maintenance Planning 1. Evaluate track condition from a great deal of inspection data. 2. and calculate kind and schedule of maintenance, to minimize long-term maintenance cost. STEP1 STEP2 Rail condition Poor Frequency of track geometry maintenance Good High Poor Low STEP3 Ballast condition Good "Big data" and "Data mining" are the key of future track maintenance STEP4 Choice of track geometry maintenance method Rail grinding or replacement Ballast renewal Full tamping Spot tamping Monitoring 23/37

24 Safety Evaluation for Track buckling Track buckling test in RTRI in kg rail, Concrete sleeper, 25 cm depth of ballast Buckling rail temp /37

25 Safety Assessment for Buckling on Boundary of Structures We developed a program to analyze track large displacement and buckling. Track buckling Vibration test of real scale track Boundary of structures Modeling of track Ballast resistance Ballast Roadbed Lateral displacement 25/37

26 Analysis of Track Buckling Condition by Simulation 変位 (mm) Displacement (mm) Week points A 点 B 点 Point-A Point-B Residual displacement Time (sec) 時間 (sec) Lateral displacement of sleepers 26/37

27 Ballast-Flying Test by Air Cannon Cannon barrel φ=105mm Accumulator (70 Litter) Ice block (30cm, 2kg) Air cannon Sleepers θ Air cannon 27/37

28 Test Video of Ballast-Flying Side view in slow motion (1kg ice block, 250km/h) Traveling direction view in real / slow motion (Deferent condition) 28/37

29 Countermeasures against Ballast-Flying Ballast screen - Grid-shaped rubber sheet - Removable in case of track tamping works Ballast stabilization agent - Resin consolidator - Broken easily in case of track tamping, and solidify again. 29/37

30 Contents 1. Outline of RTRI 2. Ballasted track and Slab Track 3. R&D on Ballasted Track at RTRI 4. For the Future of Ballasted Track 5. Conclusions 30/37

31 Future-Oriented Subjects (FY ) 露岩部 Sustainable Development of Railway Networks Innovative Maintenance Development of Railway Simulators Safety and Reliability of Railway Systems Energy Efficiency 31/37

32 Simulation of Wheel / Rail Rolling Contact FEM analysis of wheel / rail Result of simulation Application to evaluate index of wheel / rail rolling fatigue and wear 32/37

33 Internal Stress Analysis of Ballast under Wheel Loads Load [N] Loads under sleeper Result of simulation Axles' Axles passing Passing Time [sec] Application to ballast wear and track subsidence 33/37

34 Contents 1. Outline of RTRI 2. Ballasted track and Slab Track 3. R&D on Ballasted Track at RTRI 4. For the Future of Ballasted Track 5. Conclusions 34/37

35 Ballasted Track needs Maintenance To improve maintenance of ballasted track, RTRI emphasize following three research fields. (1) Clarification of degradation mechanism - Material characteristics - Contact mechanics - deformation, wear (2) Condition-based maintenance (CBM) - Automated, high-precision and high-frequency inspection - Evaluation technology (3) Cost reduction of repair works - Improvement LCC in mind - Maintenance planning system 35/37

36 Conclusions Ballasted track is still main structure of railway, and research and development to improve its performance is very important. For the future of ballasted track, clarification of its degradation mechanism is essential, and computer simulation will be a powerful tool. Performance of ballasted track depend not only on its design, but also the way and quality of maintenance. 36/37

37 Research and Development on Ballasted Track in Japan Thank you for your attention. Hideyuki TAKAI