Track for High Speed Trains on IR Challenges Ahead –An Overview Onkar Singh CE/Co-ord/N.E.Railway

1.Necessity of High Speed Trains in India. Challenges Ahead Overview Indian Railway is life line of our nation. In a developing country like India where rapid growth of economy, socio-technological advancement and multinational competitive atmosphere are taking place, IR also needs to develop its network and quality of service and that to in a competitive atmosphere. Quality is directly linked with the quality of service to the customer in terms of physical comfort and time saving.

2. Scope of High Speed Track in India. Identification of corridors for high speeds. Challenges Ahead Overview One can very well foresee early requirement of high speed trains in India. In fact on certain segments on IR like Mumbai-Ahemdabad, Mumbai- Pune, Delhi-Ludhiana- Amritsar, Delhi-Agra-Gwalior, Delhi-Jaipur, one has to think seriously for developing high speed rail services in phases in near future.

3. Standardization of track structure, bridges and other infrastructures of engineering Department in commensurate with the development of rolling stock and signaling equipments etc. suiting to Indian conditions. Challenges Ahead Overview High speed rail services are already running in many countries of the world for both freight & passengers. On most of the system high speed rail corridors are laid separately as per socio-economic need and viability. Since, there is vast existing railway network in IR, separate corridor may not be economical and so existing lines on selective basis may be developed for high speed as a interim measure.

4. Adversities of running mix traffic and other usual conflicting situations in operation to be considered in maintenance of track effectively. Challenges Ahead Overview Considering adversities by running mix traffic and other conventional wagons without much control on overloading and other such conflicting situations maintenance of such track, model of mixed traffic has to be studied in detail by RDSO. For future, IR should plan separate corridors for high speed trains connecting big cities with high rate of economical growth.

5. System of clearance of proposals of high speed routes from Railway Safety Commission - need for administrative and technical decisions. Challenges Ahead Overview In view of the above, policy decisions- both administrative as well as technical nature regarding standards of infrastructure like track, bridges, level crossings, fencing, grade separation, maintenance system, organizational setup for day to day as well as periodical maintenance units to be given proper thinking. Standardization of rolling stock, signaling and other installations has to be done judiciously. Present system of clearance from the Railway Safety Commission is also to be suitably updated after thorough experimentation and rail wheel interaction related studies for such rolling stocks and track.

6. Minimum Track Structure- Present track structure being adopted for high density route on Indian Railway may be tried for high speed trains. Challenges Ahead Overview As studies conclusively indicated that it is not necessary to have heavy track structure involving heavy cost for high speed trains but the track has to be maintained to high standard. The improved maintenance of PSC track by effective use of track machines and imparting training to P.Way staff appears to be one of the vital requirements of such high speed routes.

7. Maintenance of Track to high standards to safety as well as riding comfort to users. Challenges Ahead Overview Corrective or smoothening system of maintenance of track is not sufficient to achieve the desired riding quality and thus complete switch over to Absolute Track Geometry System of maintenance would be essential to achieve the desired level of comfort at high speeds.

8. Upgradation of Track machines on Indian Railway for high speed track. Challenges Ahead Overview As we know, at higher speeds faults in Track geometry with larger wave length also cause considerable dynamic force and therefore must be eliminated. Wavelength of 100m & 200m fault must be considered at speed of 160 Kmph and 350 Kmph respectively. Hence, change in maintenance strategy from smoothing mode to absolute track geometry is essential and track machines upgraded accordingly.

9. Threat to human life from high speed Trains during Routine Inspections and maintenance. Challenges Ahead Overview Push Trolley Inspection by field officials should be debarred at least in two block sections ahead in the face of high speed trains and suitable automatic warning system to be devised for alarming the people working on track well before. Alternatively a time slot for all type of routine maintenances and inspections may be provided.

10. Relaxation to limits of maximum cant, cant deficiency and cant excess. Improvements to turnouts is also to be considered. Challenges Ahead Overview Running of trains on curves with high speed will enhance the need of cant quadratically and therefore achieving a revised and balanced limits of the maximum cant, cant deficiency and cant excess for running of high speed trains with present mixed speed train operation system is a vital and important area of concern. Improvements in turnouts will also be an area of concern.

11. Speed limit on curves sharper than one degree. Challenges Ahead Overview Speed limit on one degree curve with existing norms of maximum cant and cant deficiency comes to 180 kmph. Therefore, an obstacle in the way of high speed trains is the population of curves of more than one degree frequently existing on almost all routes of Indian Railways. Solution to the problem may be adoption of tilting coach technology in our system.

12. Inadequate transition length for high speed trains. Challenges Ahead Overview It is well known that with increase of speed, the minimum required length of transition curve increases linearly and thus accommodating the increased transition length will compel the track to be realigned involving shifting of curves etc. depending upon the site conditions.

13. Over aged bridges –their capability to withstand dynamic impact of high speed trains & Eco friendly measures. Challenges Ahead Overview Dynamically augmented axle load of high speed trains may cause failure, Checking of some sort of samples from existing bridges and threat of it if some of the bridges fails is required to be studied. It will provide a foresight for planning the future of high speed trains. Eco friendly measures for reducing noise, dust level and vibration to nearby residents to be taken.

14. Bridge Sleepers- Stability check against dragging and other forces on high speed movement of traffic. Challenges Ahead Overview Present mechanism of holding down of bridge sleepers with girders with the help of hook bolts may defeat the purpose on high speed. A dynamic studies to check stability of bridge sleepers on running of high speed trains may be conducted by RDSO and suitable mechanism for it may be devised. Steel Channel sleepers may, however be a better option.

15. Revision of Schedule of Dimensions and Requirement of Extra Clearances on High speed routes. Challenges Ahead Overview For running of high speed trains, requirement of super elevation will go on increase. As super elevation causes the lean of rolling stocks on inner side of curves which magnifies the horizontal clearance of track from fixed / temporary structures, revision of SOD or correction to some of its provisions will be required suiting to the rolling stock for such speeds.