Major Results of Research and Development in Fiscal 2018
This publication is a collection of the major results obtained from research undertaken by the Japanese public body, the Railway Technology Research Institute, in 2018.
We would like to take this opportunity to thank all JR companies in particular and all the research centers, universities, industrial partners and other entities which have offered their cooperation, commitment and support to achieve these results and without whom none of this work would have been possible.
Ⅰ. Improvement of Safety
- This system analyzes natural hazards caused by localized heavy rainfall in real time, and calculates train stopping positions and evacuation routes for passengers to avoid hazard areas.
- This system can be used to support decisions on how to apply operational regulations currently in force in case of rainfall.
- A new portable testing device has been developed to inspect earthing systems in fixed power supply installations.
- The newly developed testing device makes it possible to perform a lightning protection testing with a faster current rise than conventional testing devices.
- The automatic data processing function in the developed device allows operators without special skills to carry out tests.
- In order to suppress the decrease in wheel load on container wagons, improvements were made to a vertical bogie damper.
- Stationary vibration tests on a rolling stock test rig were performed on a single container wagon, simulating actual cross-level track irregularity, confirming that the improved damper was able to suppress wheel-unloading by approximately 20%.
- A work method has been proposed to improve anti-catastrophe performance of railway viaducts against unexpectedly extreme earthquakes.
- A dead-weight compensation structure was developed to prevent the collapse of viaducts.
- A structure to control the direction of collapse and failure behaviour of a viaduct, is developed to help rapid repair.
- A system for verifying evacuation safety was developed to make it possible to keep a real-time visual track of the state of smoke propagation and passenger evacuation, in case of a station fire.
- The system makes it possible to verify evacuation safety based on distribution of the estimated number of people being evacuated, based on station characteristics.
- It also makes it possible to verify evacuation safety considering the effect of evacuation instructions broadcast over PA (public address) systems.
- A method was developed to give early estimations of inundated areas and water depth along railway lines due to tsunamis, using tsunami data from the open sea transmitted from public institutions.
- Using data from the 2011 off the Pacific coast of Tohoku Earthquake, it was confirmed that it was possible to obtain early estimations of inundated areas with an accuracy of over 90% approximately one hour before the time the tsunami would have made landfall.
- A system has been developed to determine the stability of slopes during snowmelt season using meteorological data.
- The system function without the need to install new observation equipment by using publicly available information.
- The new method was able to detect 20% more cases of slope stability deterioration compared to existing method.
8. Measures for reducing damage to overhead contact line system due to bridge oscillations caused by passing trains
- A computation method was developed to analyse coupled oscillation between bridges and catenary poles caused by passing trains, which also revealed the conditions under which overhead contact line system oscillations were largest.
- As a means to prevent wire fatigue failures in overhead contact line systems due to large bridge oscillations caused by passing trains, a new metal fitting was designed and a decision-making flow chart was proposed to determine whether measures had to be taken or not.
- A training method using virtual reality (VR) technology, was developed to teach railway personnel about the processes leading to man-vehicle collision accidents and the risks of working alongside tracks.
- Tests using the training method with on-site railway personnel led to a 21-point increase in the number of staff who followed rules completely.
10. Method for evaluating train running safety during earthquakes considering non-linear behaviour of structures
- A method has been developed for evaluating the running safety of trains during earthquakes taking into account the non-linear behavior of structures.
- Using design drawings and specifications, the method is able to rapidly detect existing elevated bridges that present a weakness in terms of running safety during earthquakes, which can help selection of suitable countermeasures and prioritization of work.
- A method for calculating the critical wind speed of overturning with the use of measured lateral car-body vibrational acceleration values has been proposed, making it possible to evaluate the resistance to overturning in accordance with a train’s actual running conditions.
- A stochastic interpretation of the critical wind speed of overturning following analysis of the frequency of occurrence of lateral car-body vibrations, will make it possible to add a safety margin to the evaluation of crosswind stability against overturning that reflects the assumed probability of occurrence.
Ⅱ. Cost Reduction
- A method was developed where vibrations are monitored constantly, allowing the system to detect abnormalities through comparison with normal vibrations.
- The method does not require detailed information about the design of equipment or any abnormal vibration data related to failures.
- This method also allows the classification of abnormalities and evaluation of the degree of abnormality based on the abnormal vibration rate per frequency band.
- A wheel tread friction block was developed, which reduces wear and friction of the flange by using solid lubricant.
- Tread abrasive material and solid lubricant were combined into a block, which is interchangeable with existing abrasive blocks.
- Line tests with a pendulum express train confirmed that wheel wear could be reduced by approximately 40%.
- A high-strength bolted friction joint connection method with protective rust was developed for the repair or reinforcement of weathering steel bridges.
- Design methods were also proposed corresponding to different rust conditions and different surface properties of the reinforcement/repair members.
- The new method is only 1/3 of the cost of conventional methods.
- A system was developed to monitor the natural frequency of bridge piers using microtremors measured at the top of bridge piers.
- The system allows monitoring of bridge piers even in situations where the influence of ground vibrations is significant.
- Using this method prior measurement of the natural frequency through impact and vibration tests is not necessary.
- A track structure has been developed that can be introduced at half the actual cost.
- Lateral ballast resistance force is maintained by mixing cement to reinforce existing ballast.
- Tests on a full scale model track confirmed that the track did not buckle with a rail temperature rise of 70 C
- A method using a portable RFWD for rapidly inspecting track stiffness was designed.
- The method can be used for checking track stiffness after restoration work and for designing roadbed improvement.
- A system has been developed to determine fouling of the structural clearance gauge by any of the numerous facilities that exist beside tracks.
- The device can be mounted on a track geometry inspection car, and in some sections can reduce the need for manual measurements by 90%.
- Confirmation was obtained that the error margin in the lateral direction was less than 200mm.
Ⅲ. Harmonization with the Environment
- An on-site evaluation method has been developed to characterize high-frequency noise produced by wheel and rail vibrations above 10 kHz generated on a gently curved track.
- The dominant source of high-frequency noise was identified as being the outside leading wheel of each bogie.
- The method can be used to evaluate the characteristics of wheel/rail noise and serve as a guideline for the development of mitigation measures.
- A simulator has been developed that can be used to calculate the energy consumed during train operation in an actual operating line scale, considering an installing of energy storage systems, under the condition of several lines and many types of rolling stock.
- The simulator is able to evaluate the performance of energy-saving strategies, such as introduction of new types of rolling stock and energy storage systems.
- The energy-saving performance of an energy storage system was estimated and the influence of parameters such as outside temperature, is quantitatively analyzed.
Ⅳ. Improvement of Convenience
- A method has been developed to control vertical and rolling vibrations on Shinkansen trains to improve ride comfort.
- The system combines two types of damper and one type of actuator and satisfies the double requirement of improving ride comfort whilst controlling cost.
- Excitation tests simulating actual running confirmed that the maximum ride comfort improvement was over 4dB(LT value).
- A small light-weight aerodynamic brake assembly has been developed composed of a dual-wing resistance plates.
- A computational fluid dynamics (CFD) analysis of the new assembly mounted properly on the roof of a train set showed that the stopping distance could be reduced by approximately 10% when operating with higher running speeds.
- A method for increasing braking force has been designed for a contactless linear rail brake, capable of controlling increases in rail temperature and which can be operated even with loss of power.
- By combining a new design method which exploits distortion in the magnetic field, and a new control method that employs auxiliary power sources, results found that the new system increased braking power by a factor of 1.9 compared to the previously used system.
- A new CPS contact wire has been developed with equivalent performance of the PHC contact wire used currently on recently opened Shinkansen lines, and which can be produced in small-lots, at a lower cost.
- Tests with the new CPS contact wire on commercial lines showed that the new product posed no problem from a construction point of view, nor in terms of long term use.
- To maximize the revenue of railway undertakings, a method has been developed to optimize the discount ticket sales quota, based on ticket sales data, etc.
- The method supports the decision-making process for setting the quota, making it possible to maximize revenue and facilitate decision-making.
Ⅴ. Basic Research
- The crash deformation and fracture behavior of a rail carbody structure were determined in a crash test conducted on an actual-size partial railway vehicle.
- Comparison and verification of the simulation output with results from an actual vehicle test confirmed an increase in accuracy of numerical simulation results and a maximum deformation error of approximately 10%.
- Simulation can be used for examining safety improvement measures to better protect passengers and railway staff.
- A new snow accretion simulation method to calculate the shape of snow accretion on high speed trains was developed by combining an airflow simulator with a particle simulator.
- The capacity of the snow accretion simulation method to reproduce the shape of snow accretion a cubic model was confirmed.
- This snow accretion simulation method can be used to find train shapes that reduce snow accretion.
- It has been demonstrated for the first time in the world that ground to train data transmission at 1.5Gbps using a 90 GHz band millimeter wave is possible at a running speed of 240 km/h.
- This technology can be used to transmit on-board camera images and train state monitoring data to the ground in real time, and to provide on-board passenger services such as internet access and streaming video content, etc.
29. Mechanisms underlying slope collapse due to rain or during an earthquake resulting from changes in water content of volcanic soil
- A constitutive model has been proposed to express deformation and strength characteristics of volcanic ash soil in case of change in water content.
- Based on simulations of changes in water content and strength of volcanic ash soil due to rain and during earthquakes, mechanisms underlying tephra-covered slope collapse were clarified.
- We found that alkali-silica reaction (ASR) contributes to delayed ettringite formation (DEF) progression, which is one of the factors leading to expansion deterioration in concrete.
- This has revealed the need of maintenance management that takes into account the compound causes of deterioration of concrete structures in ordinary environments.
・Ⅰ.1, Ⅰ.5, Ⅰ.6, Ⅱ.16,Ⅱ.17,Ⅲ.20 received funding from the Ministry of Land, Infrastructure, Transport and Tourism.
・Ⅰ.1 is collaborative research with National Institute of Information and Communications Technology, Tokyo Metropolitan University, Nagoya University, Toshiba Infrastructure Systems & Solutions Corporation, National Research Institute for Earth Science and Disaster Resilience, The Meteorological Society of Japan, Saitama University and Yamaguchi University under Cross-ministerial Strategic Innovation Promotion Program by Council for Science, Technology and Innovation.
・Ⅰ.7 is collaborative research with Research Institute for Natural Hazards & Disaster Recovery.
・Ⅱ.14 is collaborative research with Hosei University.
・Ⅳ.21 is collaborative research with Hitachi Automotive Systems, Ltd..
・Ⅳ.24 is collaborative research with Mitsubishi Materials Corporation, Mitsubishi Shindoh Vo., Ltd., and RYOSEI AMAGASAKI ELECTRIC WIRE.
・Ⅴ.26 is collaborative research with Osaka University.
・Ⅴ.27 is collaborative research with National Research Institute for Earth Science and Disaster Resilience.
・Ⅴ.28 is collaborative research with Hitachi Kokusai Electric Inc., National Institute of Information and Communications Technology, and National Institute of Maritime, Port and Aviation Technology under national measure that "R&D for expansion of use in radio wave resources" by Ministry of Internal Affairs and Communications.