ANNUAL REPORTFY2014
April 1, 2014 - March 31, 2015

Railway Technical Research InstituteForeword
Norimichi KUMAGAI
President
Since the Japanese fiscal year (FY) 2014 was
the final year of RTRI’s five-year master plan
“RESEARCH 2010,” we have continued research
activities to achieve the goals of the master plan.
We have implemented 280 research projects inthree key areas, that is, research and development for future railways, development of practicaltechnologies, and basic research on railways.
As part of research and development tasks
for future railways, we focused on achievements
intended to improve the safety and reliabilityof railway systems, such as simulators forearthquake motion and earthquake damage on
railways, disaster hazard mapping technologies,
and derailment-resistant railway cars. In thisreport, we have overviewed the results of our
five-year research activities on using energy more
efficiently, maintaining and expanding railway networks, revolutionizing maintenance, and building
railway simulators. To develop practical technologies, we developed an early earthquake warning
system in which seabed seismometer data areused, Shinkansen car gear oil to improve lowtemperature starting, and a tunnel micro-pressure
wave reduction method. In basic research on
railways, we tackled themes necessary to resolve
various railway-related problems: methods todecide announcements and warning sounds intrain drivers’ cabs, methods to predict inductive
disturbance on telecommunication lines covering the data transmission frequency bandwidth,stability evaluation methods for bedrock slopes byremote non-contact measurements, clarificationof the mechanism of wear of the current collecting
system materials caused by current flow, and clarification of the mechanism causing car vibrationin tunnels. In our efforts to conduct research anddevelopment more efficiently on global issues, weAnnual Report 2014-2015

have initiated joint research with three overseas
research institutes. In addition, we undertook
activities related to international standards set
by the International Electrotechnical Commission(IEC) and the International Organization forStandardization (ISO).
In order to respond to the demands of therailway industry and society, RTRI has newly enacted its vision “RISING: Research Initiative andStrategy - Innovative, Neutral, Global -” striving
to develop innovative technologies to enhance
the railways to contribute to the creation of ahappier society. Based on our vision, we haveestablished three missions, ‘Dynamic researchand development,’ ‘Neutral activities based ontechnological common sense,’ and ‘Activities
that lead global technology.’ We have initiatedmore concrete projects and adopted management
strategies to accomplish these missions. We also
formulated RESEARCH 2020, our first masterplan based on this vision, and began to implement
it at the beginning of FY 2015. The master plancalls for our activities to prioritize the performanceof dynamic research and development aiming forinnovative research and development and thecreation of top-quality research achievements that
demonstrate our overall strength.
I am confident that the value of the existence of
RTRI can be enhanced by earning trust throughhigh-quality results. We will not only tackle thechallenges of safety, energy, and greater speed,
but also efficiently invest our limited researchresources, thereby creating benefits that willrapidly and accurately meet the needs of railway
companies. In order to achieve this goal, the guidance and advice by all the railway stakeholders
are most appreciated.

1

Overview

Contents

Organization

2 Overview
4

Major Results of Research andDevelopment

Board of Trustees

Board of Directors

Auditors

34 Research and Development
56

2

Report on Key Activities under thePrevious Master Plan RESEARCH
2010

Annual Report 2014-2015

Railway Technical Research InstituteExecutive
Vice
Presidents

ChairmanPlanning Division

Vehicle Structure
Technology Division

Compliance Division

Vehicle Control
Technology Division

President
Structures
Technology Division
Executive
Directors

Administration Division
Miyazaki Test
CenterPower Supply
Technology Division

Accounting Division

Track
Technology Division

Information
Management Division

Disaster Prevention
Technology Division

Health Insurance
Systems Center

Signalling &Transport Information
Technology DivisionInternational DivisionInternational
affairs
International
Divelopment
Research &Development
Promotion Division

Materials
Technology Division

Railway Dynamics
Division

Environmental
Engineering Division

Wind Tunnel
Technical Center
Human Science
Division
Marketing & Business
Development Division
Railway Technology
Promotion Center
Railway International
Standards Center

Maglev Systems
Technology Division
Yamanashi
Maglev
Test Center
Center for Railway
Earthquake Engineering
Research(As of July 1, 2015)

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Major Results of
Research and Development
In fiscal 2014, we pushed ahead with 280 research and development projects and completed
120 of them. Major results of the research and development are shown below.

IMPROVEMENT OF SAFETY
1. Seismic ground motion simulator applicable to M9
earthquakes• 		The simulator can estimate seismic ground motion during M9 earthquakes.
• In the 2011 off the Pacific coast of Tohoku earthquake, the difference between observed and simulated
values in terms of the JMA seismic intensity scale was within ±1.
• Simulated ground motion can be used for seismic retrofitting of structures to withstand the forecast
great earthquake along the Nankai Trough.

4

The 2011 off the Pacific Coast of Tohoku Earthquake
was a massive earthquake of a magnitude of 9.0 caused
by a subduction area measuring 500 km long and 200
km wide. Seismic ground motion was observed acrossthe whole of Japan, and caused liquefaction damage as
far away as in the Kanto Region. In order to simulate theground motion of the next forecast M9 earthquake, it isnecessary to simulate dynamic rupture on a large fault
plate and the propagation of ground motion across a vast
area .
This simulator was therefore designed to represent
dynamic fault rupture processes and 3-dimensional variations in deep subsurface structures. Information about
fault models and deep subsurface structures has alreadybeen stored a database, allowing simulation of seismic
ground motion to be conducted easily with limited input
data, such as the area used for calculation and source
location, etc. When the simulator was used to simulate
the ground motion which occurred during the 2011 off the
Pacific Coast of Tohoku Earthquake, it was able to reproduce the long duration ground motion in the Kanto Region
located far away from hypocentre, even 250 seconds after
the earthquake occurred (Figure 1). As shown in Figure2,
the difference between observed and simulated values interms of the JMA seismic intensity scale was accurate towithin ± 1, validating the applicability of the simulator forM9 earthquakes.
The Government Headquarters for Earthquake

fig.1 Simulated velocity value during the 2011 off Pacificcoast of the Tohoku Earthquake (Long period components)

fig.2 Comparison of observed and simulated values, interms of JMA instrumental seismic intensity, during the 2011
off Pacific coast of the Tohoku Earthquake

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Railway Technical Research InstituteResearch Promotion has released information that there
is a 60-70% probability of a great earthquake occurring
along the Nankai Trough over the next 30 years. Using thesimulator, it will be possible to evaluate damage to railway
structures and identify points which would be particularly
vulnerable during a forecast great earthquake, in advance.

2. Seismic Hazard simulator for railways• A simulator was designed to identify locations on the railway network vulnerable to earthquakes• Comparison of simulated results with actual damage confirmed the accuracy of damage evaluation
using this simulator.
• The simulator can be used to determine locations requiring preventive reinforcement work and forecast
restoration work scenarios.
A simulator was developed to identify locations whichwere vulnerable to earthquakes on the railway network(Figure 1). Data regarding the fault, ground and structures
were collected into a database. By using the data, thesimulator constructed numerical analysis models of thefault, ground, and structure, in order to evaluate the seismic
response of the ground and structures. Information aboutdamage obtained through analysis of the data was thenlinked to map information, in order to allow visualizationof structural damage in disaster hit areas.
The simulator selects the most appropriate analyticalmodel depending on the type and volume of data. Whendetailed data is available, a three-dimensional FEM modelfor the area from the fault to the bedrock, a two-dimensional
FEM model for the surface subsoil and a three-dimensionalskeletal frame model for the structure are used. Thismethod provides a seismic response analysis of an accuracy which satisfies design calculation requirements.

Accuracy of the method was also tested by comparing estimations with data from the 1995 South Hyogo
Earthquake, and evaluating the seismic response anddamage to structures over a 13 km stretch where damage was particularly severe (Figure 2 (a)). The structures
examined were 69 viaducts. Seismic intensity evaluatedusing the simulator gave estimations accurate to within amargin of ± 0.5 with measured data (figure 2 (b)).
Accuracy of structural damage evaluation, in termsof identifying those structures which require restoration,
produced results with an error margin of approximately
12% (still within safety side assessment) (Figure 2 (c)).
These results indicate that the method is precise enoughto detect vulnerable spots on the railway network.
With the prospect of the forecast large-scale earthquake directly beneath Tokyo, and a Nankai – Tonankai
Earthquake, it is important to be able to plan seismic
reinforcement work, and construct recovery scenarios. This
simulator should serve as a supporting tool in this regard.

Fig.1 Seismic Hazard simulator for railways

Fig.2 Example of accuracy verification

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Major Results of Research and Development

3. Early warning system employing ocean bottom seismometerdata• This method proposes to employ ocean bottom seismometer data collected by public institutions foran early warning system.
• Telecommunication specifications and quality management technology are also proposed, in orderto guarantee the reliability of the warnings.
• The proposed method should increase the spare warning time for marine earthquakes occurring ear
submarine observation points.
Japan is currently expanding its ocean bottom seismometer OBS) network (Figure 1). Data about earthquakes
occurred beneath the sea collected through this network
is used for issuing early earthquake warnings, which canbe useful for railway earthquake disaster prevention. As
such a method was designed to employ OBS data inearly warnings, while telecommunication specifications
and quality management technology were developed tomaintain early warning reliability.
In the proposed method the OBS data sent to land
observation stations through undersea cables is used
to calculate the indicators which will determine whether
a warning should be issued or not. The data is sent via
telecommunication networks to the railway operators together with other information which indicates the qualityof the data. While taking into account data quality, railway
operators then issue a warning if the indicators exceed theregulatory threshold value (Figure 2).

Technology was then developed which immediately
calculates data quality information based on waveform
observation which indicates missing data, noise, etc. toensure warning reliability, and which railway operators
can refer to when deciding whether to issue a warning or
not (Table 1).
To enable multiple railway operators to share the submarine seismographic data telecommunication specifications
were subsequently defined to enable transmission of data
through a limited frequency band telecommunications line.
It is expected that using OBS data should increase thespare warning time for earthquakes by approximately 20
seconds at most.

Fig.2 Process flow chart for the early warning system using
ocean bottom seismometer data

Table.1 Quality Management Information for Data

Fig.1 Position of measurement points forming part of theocean bottom seismometer network operated by public
institutions

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4.Development of Railway Embankment Structures Resistant
to severe Earthquakes and Prolonged Overflows caused by
Tsunamis• A new design method and embankment structure have been developed to reduce earthquake damage
and increase resistance to prolonged overflows caused by tsunamis, by combining geosynthetics
reinforced soil methods and cemented gravelly-soil slabs.
Railway embankments sustained extensive damage
from the tsunami triggered by the 2011 off the Pacific coastof Tohoku Earthquake and the operations of railway lines
were suspended for an extended period of time. A new
reinforced embankment design was therefore developed
to resist seismic motion and prolonged overflows caused
by Tsunamis.
Tests on a model embankment were first carried out inorder to gain insight into the causes of tsunami damage.
Results showed that seismic motion weakens the leveepart and slope protection of the embankment. Subsequenttsunami overflow then erodes the embankment levee andthe supporting ground around the toe of the slope, leading
to overall instability, and eventually to collapse.
Therefore, by arranging geosynthetics reinforcement
materials inside the embankment and the protective slope,
resistance to seismic motion and prolonged overflows canbe improved. In addition, cement-treated gravelly-soil slabs
were added to the bottom of the embankment levee using
both cement-treated well-graded gravel and geosynthetics. The combined use of these reinforcement measurescomprises the new method designed to prevent erosionof the supporting ground due to scouring and subsequentinstability of the embankment (Figure 1).
Tests on model embankments showed that theconventional type embankment resisted well to a large
scale earthquake (L2 seismic motion), however half ofthe embankment was eroded within 6 minutes of tsunami
overflow. On the other hand, the newly developed embankment was hardly affected by erosion at all (Figure 2).
Preparation of a technical manual indicating practicaldesign and construction methods for the proposed structure is planned for the future.

Fig.1 newly developed embankment structure

Fig.2 comparison of conventional

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Major Results of Research and Development

5. Measures against buckling of ballasted track during
earthquakes• A test method was developed to quantitatively evaluate the stability of buckling on ballasted track
during earthquakes.
• Based on results of this evaluation method, it was found that employing sleeper anchors could reduce
lateral sleeper displacement during earthquakes by up to a tenth, thereby confirming improved track
buckling stability.
As seismic motion is acting on ballasted track, lateralballast resistance force falls, causing track panels tobuckle easily. During hot periods over the summer, rail
temperature (axial force) rises increasing the lateral force
which can lead to track buckling, and consequently further
reducing track buckling stability during seismic activity.
At the same time, no method has yet been establishedto assess the track buckling stability during earthquakes,
making it difficult to evaluate the effectiveness of measurestaken.
A test method was developed using special springs withsmall tensile load variation whereby the lateral load on thesleeper can be maintained even during shaking. Tests on alarge scale shaking rig demonstrated that it was possible toquantitatively evaluate the track buckling stability of various
anti-buckling measures, through indices based on lateralsleeper displacement (Figure 1).
Indoor tests at RTRI showed that lateral ballast resistance force greatly decreased during shaking, and whenaxial forces of rails (lateral direction loads) were high,lateral sleeper displacement was also significant (Figure2). It was then possible to confirm that anti-buckling
measures did indeed reduce lateral sleeper displacement
significantly. It was found in tests that the sleeper anchor
was the most effective of all the tested measures, reducing
lateral sleeper displacement by a tenth under this test
conditions (Figure 3).

Fig.1 Large-scale shaking table test for ballasted track

Fig.2 Lateral ballast resistance force during, before andafter shaking

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Fig.3 Effectiveness of anti-buckling measures against
earthquakes

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Railway Technical Research Institute

6. Disaster Hazard Mapping Technology• New technology has been developed to permit the display of natural hazards related to rain, wind,snow and rockfalls, in map form.
• The integrated display can show disaster factors, the magnitude of external forces and probability ofoccurrence together, thus assisting the preparation of disaster prevention plans.
Hazard mapping for natural disasters is useful for
railway maintenance and disaster prevention planning.
Having a system which could show various natural disasterfactors in an integrated display would facilitate evaluationof many different types of disaster scenarios for disasterprevention planning, and make it easier to identify thesources and external forces involved. Such a system would
also facilitate the design of effective countermeasures.
To this end, hazard mapping technology was developed
to visualize the evaluated probability of disaster occurrences frequently occurring along railway lines, such as
landslides, strong winds, avalanches, rockfalls etc., andthe safety factor of slopes adjacent to railway lines, in map
form using GIS (Geographic Information System).
The probability of disasters and safety factors are evaluated from extracted hazard factors, such as slope angles
and distribution of exposed rock, and estimated external

forces such as amount of precipitation, wind speed anddirection (Figure 1).
A combination of methods already developed by RTRI
and a new technique for extracting data about groundsurface changes using airborne LiDAR (Light Detection
and Ranging) and large area stability analyses of slopes
during rain, was used to extract disaster factors, estimate
external forces and evaluate the probability of disasteroccurrences.
Using the newly developed hazard mapping technology,
it will be possible to visualize spots vulnerable to natural
disasters. This new system will be a useful tool for disasterprevention planning, since it will be possible to visualize on
one single display not only the probability of occurrences ofdifferent types of natural disasters, but also their disasterfactors and the magnitude of external forces.

Fig.1 Disaster hazard mapping technology

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Major Results of Research and Development

7. Method for diagnosing condition of concrete roadbed intunnels• A vibrating device was designed to facilitate the diagnosis of the state of health of concrete railway
roadbeds in tunnels.
• Based on the concrete roadbed’s ease of movement, it is possible to determine whether or not it hasdeveloped cavities.

10

Repeated loading from passing trains on slab track intunnels with no invert can cause subsidence of the track
bed leading to concrete track bed deformation and trackirregularity (Figure 1). These problems can be detected
through abnormal track geometry readings, however, up
until now it has been very difficult to determine whether
these problems arise because of the track bed or the trackitself.
A method was therefore developed to diagnose theprimary cause of track bed subsidence, by obtaining thetransfer function (the ratios of the concrete track bed response frequency amplitudes obtained for each vibration
frequency input to the vibrator) surface areas (in termsof ease of oscillation) obtained from excitation tests on aconcrete track bed, which were used as indices, wherelarger values indicate the primary cause is located on the

track bed side, while smaller values show that it is on the
track side (Figure 2).
Application of the method to an actual tunnel, andvibration test results from before and after injection of
the material were applied to cavities under the track bed
concrete confirming the effectiveness of the proposedsystem (Figure 3).
A numerical analysis model was built to reproduce
these phenomena. It was found that there was a goodcorrelation between the transfer function surface areaof the concrete obtained during excitation tests and therate of cavity occurrence directly beneath the concrete
track bed. This leads to the conclusion that it is possible
to detect cavities directly beneath the concrete track bed
from on-site measured results (Figure 4).

Fig.1 Existence of cavities under the slab track surface

Fig.2 Diagnosis method to determine condition of concreteroad bed in tunnels

Fig.3 Vibration device test results before and after injecting
grout mixture

Fig.4 Estimation of porosity using surface area of transfer
function

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Railway Technical Research Institute

8. Analytical method for evaluating carbody safety aimed at
reducing passenger injury in case of level crossing collisions• A relationship was identified between passenger injuries in level crossing collisions and the integrated
value of carbody impact acceleration.
• It is possible to reduce passenger injuries in level crossing collisions by designing the carbody structure
to lower the integrated value of the carbody impact acceleration.
Reducing passenger injury in case of a level crossing
collision is a major issue. It is possible to calculate thecarbody impact acceleration from analyses of train collisions with obstacles, however, it is difficult to evaluate
injury to passengers. Therefore, in order to probe carbody
impact acceleration inside a train in level crossing collision,
impact analyses were conducted of a train colliding with adump truck full of sand (overall weight 22 tonnes), using
train speed as a parameter (30-130 km/h) (Figure 1).
The longitudinal carbody impact acceleration pulses
obtained through these analyses were used as input foranalysis of passenger behavior seated either on long seatsor cross seats, which in turn were used to calculate an
injury index (Figure 2). When the passenger injury index

Fig.1 Example of train collision analysis(collision speed 54km/h)

Fig.3 Example of relationship between waveform ofintegrated value of carbody impact acceleration and injury
of passengers sitting on long seats

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neared the limit level, the carbody impact accelerations
were integrated as shown in Figure 3. This figure showsthat there is a clear threshold which determines whether or
not the injury index exceeds the limit level. The integrated
acceleration value at the moment a passenger either collided with a partition wall or with the seat in front shows aclose proportional relationship with the passenger injury
index value (Figure 4).
The results of these investigations demonstrated thatthe integrated value of carbody impact acceleration was aneffective index which could be used to reduce passenger
injury. These results can also be used to establish carbody
design guidelines to improve safety against collisions.

Fig.2 Evaluation of seated passenger injury

Fig.4 Example of relationship between integrated value ofcarbody impact acceleration and head injury criterion11

Major Results of Research and Development

9. Bogie to control decrement in wheel load
• With a view to increasing protection against flange climb derailment, a bogie was developed which
suppresses decreases in wheel load with a rotating mechanism installed between the side beams
and cross beam on a bogie frame• Confirmation was obtained that this new system suppresses decreases in wheel load by approximately
40% compared to normal bogies.
When rail vehicles run through curves with largely
twisted tracks , such as transition curves emerging froma main curve, it is possible that the torsion between thevehicle bogie and the rail surface will cause a decreasein wheel load on the outside wheel of the front axle (inrelation to the driving direction). When large lateral forces
are associated to this, flange climb occurs causing a riskof derailment. Decrease of wheel load or lateral force
suppression control is an effective means to prevent
flange-climb derailment.
In order to suppress decrease in wheel load, a bogie wasdeveloped which is able to control decrements in wheelload (Figure 1) for use on conventional trailer vehicles,in the form of a rotating mechanism installed between
the side beams and cross beam of the bogie frame. The
right and left side beams of the bogie can rotate freely
in the pitching direction through the rotating mechanism.

Consequently, the device offsets the torsion generated
when the vehicle moves through large horizontal planevariations on the track, controlling decreases in wheelload and thereby improving safety against flange climb
derailment.
In order to verify the basic functions of the new device,running tests on a transition curve after a main curve on
the RTRI test line were conducted. Results showed thatcompared to normal bogies where the side beam and crossbeam are welded together, the new frame controlled andmanaged to reduce decrease in wheel load by a maximumof about 40% (Figure 2).
Further running tests on the rolling stock test bench
showed that running safety was not impaired even at a
speed of over 300km/h confirming that the new device
does not have a negative impact on running stability.

Fig.2 Effectiveness of wheel load-decreasing suppression(on exit of transition curve, in bend with radius of 160m)

Fig.1 Bogie control of decrements in wheel load

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10. Mechanical pneumatic steering system with failsafe
function• A mechanical pneumatic steering system has been developed, which is light weight, compact anddoes not reverse steer• Running tests at RTRI confirmed that the new system reduces lateral forces by 80% in curves.
Proposals have been made for steering systems which
improve driving performance through curves by extending
the wheel base on the outer rail, however, given the risk ofreverse steering due to an operational malfunction in anelectrically powered steering system, the proposal was not
adopted for practical development. Following this, a safer
steering system was developed which performs mechanical steering control based on the angle between the vehicle
and the bogie when driving through a curve (Figure 1).
The proposed system does not require electrically powered control for steering due to the new link mechanism
which connects the device which detects the bogie angle
based on interaction between the vehicle and the bogie
while running, with the compressed air control valve forsupplying compressed air to the steering actuator.
The steering actuator also has a built-in anti-reverse
steering valve, creating a mechanism where active steeringwith compressed air is only possible in the direction of
the self-steering force of the wheel. At the same time, if
a malfunction arose with the air distribution system, thenormal longitudinal stiffness of the primary suspension
acts as a fail-safe mechanism.
Tests on a vehicle equipped with the proposed systemshowed that the new steering device reduced lateralforces by 80% compared to no steering control (Figure2). Furthermore, in the case of a hypothetical malfunction
causing reverse steering, confirmation was obtained thatthe anti-reverse steering valve prevented an increase inlateral force.
As the present system was built for a bolsterless bogie,
it can be made light and compact with the same level of
performance for heavier, more complex, bolstered bogieangle linked steering trucks.
Future tasks for the development of this device include
high-speed performance tests which could not be conducted on the running test track at RTRI, and durability
tests on the bogie angle detection device, which arerequired before placing the system into service.

Fig.1 Structural components of the mechanical pneumatic
steering system

Fig.2 Results of running tests at RTRI

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Major Results of Research and Development

11. Gear oil for Shinkansen trains with improved startability in
low temperature conditions• An improved gear oil has been developed to permit safe starting of gear units at temperatures as low
as -30°C• This highly purified mineral base oil offers better low temperature fluidity, with reducing cost increase.
The Shinkansen network is being extended to regions
which are exposed to cold weather. Gear oil for Shinkansen
trains therefore needs enough fluidity to start gear units at
low temperatures of around -30°C, while having sufficient
viscosity to allow oil film formation at high temperatures.
The increase in viscosity at low temperatures of current
gear oil however means that resulting fluidity at -30°C is
insufficient. However, gear oil which uses synthetic baseoil is more expensive than the gear oil used at present.
Therefore, a new gear oil was developed which not only
has sufficient fluidity at these low temperatures but also
keeps extra cost to a minimum and ensures gear units areable to start at low temperatures of around -30°C (Figure1). The developed gear oil uses a highly purified mineral

oil as the main base oil, which is purer than the one usedin current gear oil, and contains different additives.
Tests on the state of the gear oil at low temperatures
demonstrate a lower viscosity at temperatures of -20°C,
and a depression in the pour point, confirming better fluidity
at low temperatures (Table 1).
Starting tests on a gear unit in a cold environment
showed that even when the oil level has fallen to theminimum limit, the gear unit was able to start stably at atemperature of -30°C (Table 2).
Tests confirmed that oxidation stability, resistance toloads and anti-wear performance of the new gear oil, werecomparatively the same or better than in the current oil.

Table.1 Properties relating to low-temperature fluidity

Table.2 Results of low temperature starting performance
tests (-30°C )Fig.1 Change in kinematic viscosity according to temperature of current and developed oil

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12. Process to select appropriate sounds to convey in-cab
driver alerts• A process has been developed to select what kind of sound signals should be used for in-cab alarms
or alerts.
• This process facilitates the selection of sounds or voice messages to match the level of urgency.
A rise in recent years in the type and variety of driving
assistance and safe-guard technologies, a growing numberof sounds emitted inside driving cabs, and an increasing
variety of tones used for warning devices has raised theconcern that this may distract or affect the concentrationof drivers, and therefore work has begun on developing adesign guideline to unify sound alerts.
A chart has been proposed for designers to help choosesounds when adding any new sound alerts.
The importance of the information to be conveyed was
split into four categories (hazard level) according to likelihood of an accident, and selection criteria were devisedfor each category (Table 1 ).
The chart contains example sounds and voice messages for each hazard level based on the degree ofurgency they made drivers perceive.
A checklist is proposed to guide the selection between
sound and voice, based mainly on frequency of use,characteristics of the sound which could be confused withexisting alerts, and to limit number of the sounds to an
acceptable level, etc .
Methods for determining sounds according to urgencyof the warning already exist in the automobile and aviation
sector. However, the railway environment is very different,
given the type of information, the complexity of required
responses, the supposed sound environment and theexisting visual and audio information burden.
Consequently, based on interviews with those responsible for system design, and tests and surveys with on-board
staff, a classification and voice-notification method suited
to railways has been proposed.
By adopting a uniform approach to in-cab information
drivers will be able to instinctively perceive hazard levels,
while it would also reduce the possibility of selecting easily
confused sounds and allow clear delivery of the intended
message to drivers.

Table.1 Process and decision-making factors for selecting sounds (extract)

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Major Results of Research and Development

13. Training in communication techniques for train dispatchers
in disrupted situations• A training method was developed in order to give train dispatchers the necessary communication skills
for giving instructions or orders in disrupted situations• This method was shown to improve the accuracy and smoothness of communication in disrupted
situations, and cooperative behavior.
In traffic control, it is important to share information
accurately and smoothly between key employees, suchas between traffic controllers managing traffic, crews andtrain vehicles.
To address this challenge, a training method in communication techniques was developed which is easy to
implement in the workplace (Figure 1).
Participants to the training were divided into groups
according to roles, and then exposed to a simulated disrupted situation where they were required to communicate
with each other. Their behavior and conversations werevideoed during the training, and they viewed these recordings together after the drill. One to two months after the
training, checks were made to see if the program helped
participants to communicate better in the course of theirordinary work, which was followed by a final round of
feedback on the training.

A list was drawn up of 45 points to remember in termsof communication skills, such as “when there is danger,
your voice should be more assertive”, etc. Two types ofquestionnaire were compiled for each of the 45 points. The
first asked “how important do you think these techniques
are?” and the other asked “to what extent do you apply
these techniques at work?” These questionnaires proved
to be an effective way to measure how the acquired skills
had been adopted and applied, even some time after the
training, and helped to accelerate the acquisition of communication techniques.
Confirmation was obtained that this training increased
awareness of the importance of communication techniques
while it also increased actual application of these skills in
the workplace (Figure 2).
The present method can therefore help to reinforce
cooperative behavior and smooth sharing of accurate
information between relevant employees in disrupted
situations.

Fig.2 Comparing before and after training in communication
techniquesFig.1 Outline of training method

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HARMONY WITH THE ENVIRONMENT

14. Hood with inside partition to reduce micro-pressure waves• As a measure to reduce micro-pressure waves as Shinkansen train speeds increase, a hood with aninside partition has been developed. The micro-pressure wave mitigating properties of these hoods
were verified using theoretical analysis and model experiments.
Tunnel entrance hoods, which are installed at tunnel
entrance portals (where trains enter the tunnel), are acommon infrastructure-side measure used today to reduce micro-pressure waves emitted from tunnel portals.
Tunnel entrance hoods have to be extended in line withtrain speed, however, beyond a certain length the hood is
no longer effective, which is a problem.
Therefore, in order to meet new demands associatedwith increasing train speeds, a proposal has been madefor a new infrastructure-side measure, i.e. to install a hoodwith an inside partition at the tunnel exit portal (the train
exit side). Like existing tunnel entrance hoods, the newhood has a larger cross-sectional area than that of themain tunnel. It has a partition which divides the inside of
the hood into two parts in the vicinity of its mouth, andone end of the partition is closed (Figure 1).

The partition splits the compression wave inside thetunnel, which is the source of micro-pressure waves, andalthough the micro-pressure waves are still emitted several
times, the system reduces its peak value (Figure 1).
According to acoustic theory, the effectiveness of thishood with an inside partition on reducing micro-pressure
waves should be approximately proportionate to the
opening ratio (Opening cross-sectional area / hood crosssectional area), (provided 0.5< opening ratio<1). Modeltests validated the acoustic theory conclusion confirming
the effectiveness of the hood (Figure 2).
In the case of suppressing micro-pressure waves generated by oncoming trains entering the tunnel at an end
equipped with one of the new hoods, if the cross-sectional
area of these new hoods and open windows distributed
along its length are suitably adjusted, the new hoods will
maintain the same functional performance as existinghoods of the same length.

Fig.2 The reduction ratio of the micro-pressure wave byhood with inside partition
Fig.1 Micro-pressure wave emission from the hood withinside partition

Annual Report 2014-201517

Major Results of Research and Development

15. Improved accuracy train energy consumption simulator• A traction power supply simulator has been developed with coupled analysis between fixed installations,rolling stock and driving pattern.
• An algorithm for generating speed profiles was developed to generate average energy consumption
speed profiles during commercial service, and energy-saving speed profiles.
In order to reduce energy consumption in the railways, various kinds of both fixed installations and rolling stockside solutions are being investigated, and more accurateenergy simulators are required to estimate the efficiencyof each of these measures.
To this end, a traction power supply simulator wasdeveloped. Detailed calculations were made of the interaction between current and voltage between several
trains and several traction substations, with precise speed
profiles reflected by changes in acceleration due to voltagechanges . In order to verify the fidelity of the simulator,
comparisons were made between calculated and measured values obtained from tests using two trains running
through a feeding section with two temporarily isolated
substations. The results showed the correlation between
the feeder current and the train speed was almost identical(Figure 1). It was confirmed that data about the trains’energy consumption could be calculated to within 5%,
and power for the substation to within 8 %.

It is well known that energy consumption varies greatly
in accordance with driving patterns, and therefore simulations need to be made by generating speed profiles which
are as close as possible to reality. Two algorithms for generating speed profiles were developed: one for generatinga speed profile for energy estimation, utilized to calculate
average energy consumption of train operations, andone for generating an energy-saving speed profile which
can be an example of train operations to reduce energy
consumption. Verifications were made to ensure that the
speed profile for energy estimation was indeed a realistic
representation of actual driving, and its energy consumption was also close to the averages found in commercial
train operations (Figure 2). Another result confirms thatthe low energy speed profile will enable energy-saving
operations to be made.

fig.1 Verification of traction power supply simulator

fig.2 Verification of algorithm for generating speed profiles

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Railway Technical Research Institute

16. Induction predicting simulator applicable to datatransmission frequency bands• A simulator was developed for quantitatively predicting inducted voltage and current up to datatransmission frequency bands of 1MHz and above.
• The extended ability to consider more conditions relating to fixed installations has led to an improvementof 10% in accuracy of prediction.
Induction voltage and current in trackside telecommunication lines are caused by feeder voltage and groundreturn current (Figure 1). As a means to prevent problems
such as electrocution and interference with telecommunication lines, countermeasures of equipment based on
results of prediction calculations have been implemented.
However, existing methods for calculating induction
predictions could only be used in audio frequency bands.
Also these methods modified calculated values by considering influence from cable structures and iron rebars
in civil structures, which means that the calculated values
were generous approximations of induction occurrence.
Therefore, a new induction predicting simulator wasdeveloped, which is applicable to high frequency band
above the audio frequency and capable of considering
multiple conductors in structures.
The simulator uses a new method where parameters
are calculated by suitable approximation equations whichtake into account the ground effect and the skin effect ofconductors, while the model is split into smaller sections
as the frequency range increases, extending the frequency
range from the audio frequency band of 4 kHz up to thedata transmission band of 1 MHz (Figure 2).
While the new simulator removes the limit on the number of longitudinal conductors which was several dozen inold simulators, its calculation speed is also faster by using

parallel processing which is used for models with very large
calculation loads. Therefore, installation conditions can beconsidered in great detail, and the prediction accuracy wasincreased by about 10% (Figure3).
The simulator will make it possible to quantitatively
evaluate the effectiveness of anti-induction countermeasures to reduce induced voltage and induced current on
telecommunications lines, when upgrading or installing
new power, or wire-based telecommunications equipment.
The simulator can also be used for predicting voltage andcurrent induction in rails.

fig.1 Electromagnetic induction and Electrostatic induction
occurringfig.3 Overview of calculation models of viaduct and result ofvalidation of the models

Annual Report 2014-2015

fig.2 An example of prediction results in the data transmission frequency band

19

Major Results of Research and Development

17. Production of a 300m class superconducting feeder cable• A 310 m superconducting feeder cable was built along with a cooling system. Its functions were thenverified with running tests.
Before placing superconducting feeder cables into service on railways, several issues have to be resolved andmethods found for, among others, laying the cable along
the line, mitigating thermal stress which occurs in the cableduring cooling, cooling technique to ensure superconducting properties are preserved over a long distance, etc.
A prototype superconducting feeder cable system waslaid along the test track at RTRI (Figure 1), and runningtests were performed. The system was sized according to
the length of a typical feeder section i.e. 310 m, with a rated
current of 1000A. In order to reproduce conditions as close
to reality as possible, the test line was constructed witha track cross over, a level crossing section and a thermal
stress mitigation structure in the cable during cooling.
Therunning
tests
were
per-

formed after verifying the electrical properties, such as
withstanding voltage, of the superconducting feeder cable,
and those of the cooling system (Figure 2), which confirmed
the conductive properties of the system during operation.
Given the superconducting feeder cable’s capacity tosupply electricity with zero electrical resistance, it can beused as a measure to prevent voltage drops and reduceloads on traction substation, etc. Future work is on conducting field tests with the new system, and designinga technical architecture to place the system into active
service.

fig.1 310 m superconducting feeder cable

fig.2 Cooling system

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Annual Report 2014-2015

COST REDUCTION

Railway Technical Research Institute

18. Renovation technology for large scale station wideningwork• A new design method was developed for large scale underground station extension work and building
connections between old and new tunnels.
• The tunnel connecting work method can offer cost savings of approximately 10% compared withexisting techniques.
Facing the growing need in large city undergrounds
to reduce congestion and improve functionality there isincreasing recourse to station extension work where part ofan existing underground tunnel is opened and connected
to a new tunnel to widen the area. However, large scale
extension work involves significant reinforcement of theexisting tunnel.
A new working method was therefore developed, which
combines vertical and horizontal anchors crossing over,overlapping onto the existing tunnel (on the ground side)with a projected reinforced beam (Figure 1).
The reinforcement beam supporting the structure in the
track direction serves to consolidate the existing and newtunnels into a monolithic structure ensuring transverse
resistance, and which prevents any increase in sectional
force in the existing tunnel. Full scale loading tests showedthat the connecting section did not break, and the new andexisting structure behaved as a monolithic block validating
the fact that this construction method possesses the desired flexural capacity required for applying the proposed
design method into practice (figure 2).
Trial calculations for a standard two tier, double spantunnel showed that compared to the existing method, lessreinforcement work is required on the existing tunnel tocarry out the extension work, which should enable a cost
reduction of approximately 10%.

fig.1 Outline of connection method used in large scale extension work

fig.2 Loading testing on full scale replica

Annual Report 2014-2015

21

Major Results of Research and Development

19. System for monitoring soundness of railway bridges• Using wireless technology, an inspection method was developed to monitor the state of railway bridges.
• A method was proposed to diagnose the soundness of railway bridge piers using indices correlated
highly with the natural frequencies of bridge piers.
As railway bridges age, there is a growing demand for
low-cost maintenance procedures.
Until recently, the soundness of bridges was diagnosed
using field measurements, impact vibration tests etc.
Now, however they can be diagnosed effectively using
monitoring methods that track their soundness. As sucha monitoring system was developed comprising an acceleration sensor for measuring pier vibrations, and sensors
to detect bearing point displacement between the piersand girders, powered by batteries charged using power

generated from steel girder vibrations. In addition, a wireless transmission device was developed to add to thismonitoring system to allow data to be collected remotely,
without going on site (Figure 1).
It was deemed that for bridge piers, a monitoring system
based on the structure’s natural frequency would be particularly efficient. Therefore, a new soundness diagnosis
index for bridge piers was devised, drawn from sources
closely correlated to the natural frequency of bridge piers,
such as the power spectral area ratio of micro-tremors(ratio of total area to low frequency area) (Figure2).
Confirmation was obtained that this index canbe used for diagnosing the soundness of actual
bridge piers over the long term (Figure 3).

fig.1 Outline of railway bridge monitoring system

fig.2 Soundness diagnosis index correlated with natural frequency

fig.3 Monitoring method for the soundness of bridge piers based on proposed index

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Railway Technical Research Institute

20. System for evaluating the stability of rock slopes using
remote-contactless measurements• A remote contactless measuring system was developed to observe oscillations and the shape of rockblocks on rock slopes. A tool to evaluate the stability of these boulders by performing FEM analyses
on the collected data was then developed.
• The present system allows detailed numerical analysis evaluation and simple nomogram based
evaluation.
In order to prevent rockfalls from rock slopes adjacent
to railway lines, it is necessary to identify unstable rockblocks and take preventive action. A method was therefore
developed to enable the safe and efficient assessment of
the stability slopes in hard-to-access, isolated or high-up
locations (Figure 1).
The contactless vibration measuring system (Figure1-a) can detect micro-tremors on a rock face using red
or infrared laser beams at distances of ten to several
hundred meters. Where possible, unstable rock blockvibration characteristics are evaluated on the basis ofordinary micro-tremor data, while stable rock blocks withvibration characteristics which do not appear clearly fromordinary micro-tremor data are examined using acoustic
vibration etc.

The aerial survey system (Figure 1 –b) comprises
a camera-mounted radio controlled helicopter, whichflies around the target rock block collecting data about
its shape from aerial photographs. This data is used tosemi-automatically create a FEM analysis model of therock block (Figure 1-c).
This research offers two safety evaluation methods,
one through numerical analysis, based on the dominantfrequency of the boulder obtained from vibration measurements and on an FEM analysis model, which offers detailed
stability assessment under normal conditions and in caseof an earthquake (Figure 1-d); the other simpler evaluation
method uses the dominant frequency to determine a fallingsafety factor in relation to the rock block’s boulder’s stability
against collapse in nomogram form (Figure 1-e).

fig.1 Remote contactless measurement system to evaluate the stability of rock slopes

Annual Report 2014-2015

23

Major Results of Research and Development

21. Track maintenance planning systems applying veryfrequently measured track irregularity data
• A method for predicting rapidly degrading track irregularity and diagnosis model were developed foruse with very frequently measured track irregularity data, which were then used to develop a track
maintenance planning system.
• In addition to track maintenance planning, the system can be used for diagnosing rapidly deteriorating
track irregularity, and diagnosing track condition .
Track measuring equipment to obtain track irregularity
data on a very frequent basis was introduced on Kyushu
Shinkansen trains in 2009. Since then, similar measurement equipment has been introduced on commercial
trains, including conventional trains. Given the volumeof data which can be measured in this manner, there isa need for efficient data processing to use this data in
high-precision prediction and track condition diagnosis
methods. Based on suitable data processing and use, thishigh frequency data has been employed to develop a track
maintenance planning system.

fig.1 Accuracy of new prediction model

A model for calculating track irregularity deterioration
suitable for very frequently measured data was developed.
Application of this model to a section of track demonstrated
that the 12-month predictions obtained using this model
were high accurate to within +/- 0.16 mm (97% accuracy)(Figure 1). Then, by using historical data covering 6-monthor longer periods from the previous year, it would bepossible to obtain sufficiently accurate predictions withmeasurements taken only every half month.
A model for predicting seasonal changes in track irregularity was also developed, which produced equally
accurate half-yearly predictions. Additional models weredeveloped to evaluate ballast deterioration, which focuseson the durability of track maintenance work, and diagnosisof rapid deterioration of track irregularity by comparing
long-term trends with latest trends in each location.
These new models mean that it is now easier to use veryfrequently measured data to locate rapid deterioration of
track irregularity and detect sections with defective ballast.
Using the above results, a frequent-measurement based
track-maintenance planning system was developed (Figure2). The locations identified as requiring track irregularity
maintenance in the plan obtained by the system, were 10%
closer to the actual sites needing maintenance comparedwith the conventional approach, indicating that this model
offers plans which are a closer reflection of reality. The
system can also be used for diagnosing rapid deteriorationof track irregularity and ballast condition diagnosis.

fig.2 Track maintenance planning system suite for used with frequently measured track irregularity data

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Railway Technical Research Institute

22. Rail gas pressure welding process applicable without
specialist welding skills• Following the development of a simplified rail end surface grinding process and automatic burner
oscillator, a new gas pressure welding process for rails has been proposed, which does not require
specialist knowledge or skills for operation.
• Verifications confirmed that the new process offers the same performance as the previous method.
A common rail welding method used in Japan is gas
pressure welding. This technique however requires specialist skills for the rail end surface grinding process andrail heating stage using a burner. A new simplified andstandardized gas welding method has therefore been
discussed and developed with minimal requirement ofspecialist skills.

Examination of the rail-end surfaces on newly manufactured rails revealed that the contact surface required forgas pressure welding sufficiently flat, confirming that gas
pressure welding can be performed after simply removing
any rust with a small-scale grinder. An oscillating pattern forthe burner was proposed, which offered sufficient bonding
strength, and avoided excessive melting of the rail surface
during the heating process. Based on this, a standard
swinging operation was set, and an automatic burnerswinging device was developed, capable of reproducing
the proposed swing pattern (Figure 1).
Tests were performed on the gas pressure welds on a
JIS60kg standard carbon rail manufactured according to
the newly developed gas pressure welding process (Table
1) to evaluate its performance. Results showed that theperformance of the new welding process was equal to thatof existing methods.

fig.1 Pressure welding with automatic burner oscillator

Table.1 Proposed rail gas pressure welding process (rail used in this example: JIS60kg standard carbon rail)

Annual Report 2014-2015

25

Major Results of Research and Development

23. Updating of on-board train safety database using
wireless technology• A new method has been developed using wireless technology to update the on-board safety databaseson trains• While checking data validity, this system allows efficient simultaneous updating of multiple databases.
Over recent years, the development and introduction
into service, of train protection systems using on-board
databases (DB) has increased. On-board databases
contain safety critical data such as track data and vehicle
performance data. However, upgrading these systems
is very labor intensive and time consuming, since thecompact flash cards used for data storage have to bechanged one by one in each system.
In an attempt to improve the efficiency of the DB upgrading process, a system was developed using wirelesstechnology, and a prototype model was built for use with
the ATS-Dx train protection system (Figure 1).
The prototype was built to be able to use the licensefree general purpose 5.6 GHz frequency band wirelessdevices for safety data transmission, and the data validity checking method was designed to guarantee safety,
taking into consideration the need to cut the volume ofdata being transmitted (Figure 2), while a special datatransmission format was devised to protect data security
during transmission.
Results from tests using the prototype show that it waspossible to maintain the same level of data validity as
previously, and that it was possible to conduct multiple
unit upgrades simultaneously.
This method will contribute to the increase in database
updating efficiency when trains are brought into a depot
for service.

Fig.1 Outline of prototype system

Fig.2 Outline of method for verifying transmitted data validity

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Railway Technical Research Institute

24. Device for determining AC feeder lightening arrester
damage• A device has been developed to determine whether arresters with zinc oxide (ZnO) elements havebeen damaged.
• Given that deterioration can be determined using this method by measuring current leakage fromground wires, power cutting is no longer required.
Lightning arresters in AC feeding circuits protect electrical equipment from lightning or switching surges. They
usually contain zinc-oxide elements inside a porcelainbushing (Figure 1). Given that deterioration of lightning
arresters exposes electrical equipment to damage, it isnecessary to grasp the state of these arresters on a regularbasis. Deterioration of the surface of insulating housing canbe detected from increased current leakage, however, it isdifficult to check for deterioration of the zinc-oxide elements
inside the insulation housing.
If the zinc-oxide elements have been damaged, theleakage current increases when high voltage is applied
to the lightning arrester and distorts the waveform (Figure2). Waveform deformation caused by current leakage canbe detected through an increase in a plurality of harmonicFig.1 Structure of lightening arrester and devicefor determining deterioration

Annual Report 2014-2015

currents, and so this effect was employed to develop adevice to determine whether the lightning arrester had
suffered damage or not.
When lightning arresters are damaged, 5th-15th orderharmonic currents can be detected by Rogowski coil andband-pass filters; when the threshold number of harmonicelements is exceeded, the damage indicator lamp lights
up, indicating that deterioration has been found.
The validity of the indicator function was verified byartificial fault tests using damaged zinc-oxide elements anda capacitor. Field tests also demonstrated that this method
did not misdiagnose undamaged lightning arresters. The
device only weighs 10 kg and is compact, facilitating
practical on-site inspections, thereby helping to reduce
maintenance costs.

Fig.2 Outline of method for verifying transmitted data validity27

Major Results of Research and Development

IMPROVEMENT OF CONVENIENCE
25. Method for assessing seamlessness of passenger
mobility in the railway transport system• A method has been developed to quantitatively assess the seamlessness of passenger mobility inthe railway system.
• The method helps to identify bottleneck stations on intercity and city railway networks, and can beused to evaluate the effectiveness of improvement measures.
In an attempt to increase convenience to rail users it
is important to consider smoother mobility not only for the
railway network but also for all transport modes along thewhole of the transport chain.
Since stations are main nodes in the overall transportsystem, a new method was devised to evaluate stationlayouts in order to offer rail users a seamless transfer
environment, (Figure 1).
Using actual national passenger movement data for theinter-city rail network and mathematical optimization, it waspossible to identify bottleneck stations, where the numberof passengers passing through a station is expected to
exceed the design capacity of existing facilities (Figure1). In the case of city networks, bottleneck stations, wherelarge passenger crowds are expected, were identified witha mathematical model designed to represent the choices
made by different rail user profiles according to situation(express-train users, local train users, etc.) by crossing
data from train timetables and OD by time band (transportation volume between each Origin and Destination)(Figure 1).
Questionnaire surveys were then conducted among
passengers in the stations where bottlenecks had been
identified to enquire about the psychological and physicalpressure (resistance to mobility) they felt when transferring
between transport modes. These results were used toconstruct a model to evaluate transfer convenience (Figure
1).
After taking into account future transport situations
and policies, this method can be used to help allocate
investment towards stations or for facilities which mostneed improvement, and can be used to evaluate the effectiveness of such improvement measures.

Fig.1 Flow chart illustrating the evaluation process for seamless mobility in the railway network

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Railway Technical Research Institute

26. Railway Freight Transport Evaluation method• A synthetic method to evaluate railway freight transport has been developed, composed of a modelbased quantitative evaluation of freight transport for economic efficiency, and system to visualize
train’s loading conditions for each corridor.
• This method can be used to identify railway freight related problems and to assess the effectivenessof any improvement measures.
Efforts to improve the efficiency of freight transport arebecoming increasingly urgent in an era where global warming has become a key societal issue, compounded by low
birth rates & an aging population. Therefore, a systematic
evaluation method for freight transport was developed, notonly to evaluate the economic efficiency and effectivenessof freight transport, but also to provide an overall visual
representation of freight train loading conditions (Figure 1).
Based on the knowledge, viewpoints and expertise oflogistics professionals, such as shippers , a quantitativeevaluation model was built, with 13 related index items
covering 5 aspects generally considered by logistics
managers, which were each weighted with the responses
to an online questionnaire data. The model offers a holistic
assessment of freight transport, allowing comparison ofrail and road freight transport options and highlighting

comparative drawbacks in rail transport in relation to theroad. This information can then in turn be used to devise
measures to improve railway freight efficiency.
Railway Freight Geographic Information System (RFGIS) was developed to provide a visual evaluation systemof the loading conditions of freight train, based on train
diagram data and actual freight loading & unloading operation schedules. Such the system provides a clear view ofthe loading conditions of freight train on each route fromdeparture terminal to destination station.
This evaluation model and RF-GIS allow visualization of
the current state of traffic and loads on the freight network,
which in turn can serve to design targeted measures toimprove rail transport efficiency, such as increasing accessibility to freight trains, etc.

Fig.1 Railway freight evaluation system

Annual Report 2014-2015

29

Major Results of Research and Development

27. Small, low-cost pneumatic centering cylinder for tilting
trains• A small, low-cost pneumatic cylinder has been developed to mitigate lateral bump stop hitting whenrunning through curves, and which does not require, electrical controllers and sensors.
• The new device improves the lateral ride quality level (LT) of tilting vehicles, which use air-springs
as tilting actuators, by 2-4dB.
The number of active tilting trains with air-springs which
do not require special bogie structures has increased overthe past few years, in an attempt to improve ride comfort
on board trains running through curves.
However, tilting trains with air-springs undergo greater
lateral displacement in curves than pendulum trains, which
in turn have been blamed for lower ride comfort due to theimpact on lateral bump stops.
Consequently, a centering cylinder (Figure 1) has beendeveloped to control the lateral movement of carbodies.
The centering cylinders are fitted parallel to the lateral
dampers on the bogie (Figure 2), and exert a restoring
force to counter lateral displacement, thereby controlling
the lateral movement of the carbody and reducing impact
on the lateral bump stops.

Fig.1 Centering cylinder

Fig.3 Example of reduced lateral vibration acceleration in
curves30

Even though the driving force of the cylinder uses compressed air, the valve mechanism controlling the air supply
to the cylinder is mechanically built into the piston-rod
part of the cylinder, and therefore no separate controller
nor sensor are required, keeping the size and cost of thedevice to a minimum.
The results of running tests on conventional line express
trains demonstrated that lateral vibrations of around 2 Hz
produced by impact on the lateral bump stops, fell (Figure3), and that the lateral ride quality level (LT) in successive
curved sections could be improved with a reduction of
approximately 2-4 dB (Figure 4).
This device can be used not only on air-spring tilting
trains, but as an improvement measure on any trains
where the effect of lateral bump stops on ride comfort incurved sections is proving to be a problem.

Fig.2 Installation of device onto vehicle

Fig.4 Example of improved ride-quality level (Lt) in continuous curved track section

Annual Report 2014-2015

BASIC RESEARCH

Railway Technical Research Institute

28. Construction of large-scale coupled wheel-rail-ballast
analytical model• A dynamic rolling contact analysis model has been built in which wheel/rail plastic deformation canbe considered.
• Dynamic response and subsidence behavior of the tracks can be evaluated by the constructed model
based on Quadruple Discrete Element Method (QDEM).
In order to gain greater insight into the causes of ballasted track deterioration, it is critical to be able to evaluate
wheel/rail contact forces and dynamic internal behavior ofballast with high precision.
A rolling contact analysis model able to deal withwheel/rail plastic deformation was therefore built, usinga large-scale parallel FEM structural analysis program(FrontISTR). Figure 1 shows the equivalent stress distribution obtained using a 2-wheel 2-axel wheelset model.
On the other hand, a Quadruple Discrete Element
Method model (QDEM) was developed to build a ballasted
track model capable of reproducing different ballast statesin detail. The impact loads calculated by the wheel/railrolling contact model were input into this QDEM program.
Weekly coupling of these two models, made it possible tosimulate track subsidence due to elastic vibrations androlling / displacement of the ballasted track caused bypassing trains (Figures 2 and 3).
A FrontISTR based ballasted track model was also
built placing springs in the contact areas in the ballast
and under sleepers. Transient response analyses werethen conducted to reproduce the vibration modes in theballast layers which influence ballast flow and subsidence(Figure 4).
In future these analytical models can be used to gain
deeper insight into mechanisms leading to ballasted track
deterioration, rail shelling, corrugation wear, and so on. It
is also expected to be used to evaluate various corrective
measures.

Fig.1 Dynamic contact analysis considering elastoplasticity

Fig.2 Stress distribution by inputting running load

Fig.3 Time history response of vertical displacement ofballastAnnual Report 2014-2015

Figure 4 Response displacement of the ballasted trackusing contact springs in FEM analysis

31

Major Results of Research and Development

29. Wear mode map of current collecting materials• An electrical contact model was developed considering film resistance in electrical wear on current
collecting materials. Insight was then gathered into “melting bridge” generation, and an electrical wear
map was produced.
• The wear mode map can be used for predicting the wear mode and can contribute to future material
development.
Up until now, it was thought that arc discharge, duringloss of contact, was responsible for massive wear to current collecting equipment, i.e. the contact wire and contact
strip on the pantograph.
Recent research however has revealed that melting
bridge of the materials just before arcing seems to be thereal cause for electric massive wear.
Consequently, an electrical contact model was built taking into consideration film resistance, such as oxide films
on the contact surface, in order to conduct a temperature
distribution analysis and gather insight into the mechanisms generating melting bridges due to heat generation
during current collection (Figure 1).
The result of analysis showed that when an iron-based
sintered alloy contact strip is used in combination with a
hard-drawn copper contact wire, the film resistance on thecontact wire causes heating and raises the temperature of
the contact wire. Consequently the difference in melting
points generates “contact wire melting wear mode” andcauses the melting bridge in contact wires. Inversely, it was
found that if there was no film resistance on the contact
wire, the contact wire would not melt even during current
collection, and only the contact strip would melt, causing“contact strip melting wear mode”.
Temperature distribution analysis was used to compile a “wear mode map” of current collecting materials,
based on factors influencing contact wire and contact strip
melt, identified as being: (1) contact voltage, (2) melting
point of materials, and (3) contact resistance including
film resistance, giving a quantitative visual rendition of
the conditions associated with the wear mode generated
during current collection (Figure 2).
Tests were used to confirm that it was possible to map
consistently the electrical wear mode of other material
combinations.
Wear mode map can be used in future for predicting
wear according to combination of current collecting materials, and can also contribute to new material development.

Fig.2 Example of wear mode map (Hard-drawn copper
contact wire - Iron-based sintered alloy contact strip)

Fig.1 The electrical contact model and analysis result ofheat distribution

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Railway Technical Research Institute

30. Mechanisms of flow-induced vibrations of trains
running in tunnels• To clarify the mechanisms underlying vibrations in high-speed trains running through tunnels, a
simplified model was used for analysis. This demonstrated that meandering air underbody air flows
generate train vibrations in tunnels.
Although variation in air pressure has already beenfound to be the likely cause for train oscillation in tunnels,
the mechanisms generating air pressure variation are not
yet understood.
First, a simple model was built of a 6-car high speed
train fitted with small scale helical-groove airflow meters on
the underbody of the cars, and used to carry out numericalsimulations of the simple phenomenon of airflowing aroundcarbodies on a train running along a stretch of open track.
Results of this test showed that underbody airflows wereslower than airflows along the side of the train. The difference in airflow speed produced large Karman vortex-likevortices (staggered Karman vortex street), which in turncaused meandering airflows beneath the train (horizontal
left-to-right moving airflow) (Figure 1).
When the same numerical analysis was applied to atunnel run, the meandering airflows followed the tunnel
wall side and rose up the side of the model train. This was
identified as being the possible cause for train oscillationin tunnels (Figure 2).
It was confirmed that the predicted meandering airflow
found through numerical simulation also occurred in actual
wind tunnel tests.
The next step in this research will be to use more realistic model trains in further tests to gather deeper insight
into the phenomenon.

Fig.1 Mechanism causing meandering air flows (producing fluctuating air pressure along the side of the train)

Fig.2 Meandering airflow

Annual Report 2014-2015

33

Research and Development

1

Vehicle Structure Technology
Division

The Vehicle Structure Technology Divisionconsists of four laboratories, namely, the Vehicle
Dynamics, Running Gear, Vehicle Noise andVibration, and Vehicle Strength Labs. They are
responsible for a wide range of matters related
to safety, stability, comfort, durability etc. The following is an outline of various research activitiesof the Division in FY2012.
The Division worked on a total of 18 researchand development themes, of which 3 were futureoriented challenges, 4 were practical technology
development themes, and 11 were basic research
themes related to the railways.
Regarding consultation work, the Division
responded to requests for advice from railway
companies concerning the investigation of incidents such as equipment failures and accidents,
studying countermeasures, the clarification of
the performance of new vehicles, and so on.
Regarding contract work, in addition to individual
requests from railway companies, it conductedsurvey research (entrusted by the national government) on the impact of vibration of vehicle
equipment.

■ Vehicle Dynamics

The Vehicle Dynamics Lab develops safety
evaluation methods and simulation technologies
related to the running safety of vehicles. To study
the impact of crosswind on flange climb derailments, it conducted running tests under crosswinds using actual vehicles on the test track at
the RTRI (Fig. 4-1-1). It also performed a similar
test using a 1/10 scale vehicle in the Maibara
Wind Tunnel. The results revealed that crosswinds with velocity lower than about 25 m/s havealmost no impact on flange climb derailments.
To study a method of evaluating running safety
during relief running, a running test was carriedout with a punctured air spring on the test trackat the RTRI, confirming the appropriateness of a34

Fig 4-1-1 Image showing the cross wind running test

simulation using an air spring model in the eventof a puncture. To evaluate the impact of abrasive
blocks on concave wheel wear, an accelerated
wear test was conducted, and the wear analysis
model was improved to consider lateral oscillation. To re-validate safety when carrying outsize
containers, the Lab investigated the actual stateof car-body vibration to estimate the distance
between the container and the clearance gauge. It
also carried out a numerical analysis to study the
impact of wind pressure or lateral uneven loadingof containers on car-body displacement.

■ Running Gear

The Running Gear Lab works to develop ways
to improve the functions of vehicles and riding
comfort. To develop a rapid prototypebogie, it
has built a simple test system to study and verify
how to deal with sensor noise or dead time thatmust be considered in actuator control. In orderto renovate car-body tilting technology, the Lab
has developed a tilt mechanism applying an antirolling device that both mitigates motion sickness
and improves vibration riding comfort. To lower
lateral bump stop hitting for vehicles which tilt
their bodies with air springs , the Lab developed apneumatic centring cylinder and conducted a running test and confirmed that it effectively improves
riding comfort. A vehicle excitation test on therolling stock test plant confirmed that vertical andlateral vibration control systems reduce the vertical and lateral vibration simultaneously and also
Annual Report 2014-2015

Railway Technical Research Instituteeffectively improves riding comfort. To develop asteering bogie, the Lab studied the applicationof a magnetic elastomer whose storage modulus
could be varied by changing the applied magnetic
field; this method can help vary the longitudinal
stiffness of the axle box suspension. To develop
a condition monitoring system of a bogie, theLab proposed the methodologies of detectionsof the undesirable oscillations caused by thehunting motion of the bogie and the damage ofdelaminated surface in the axle box bearing, andvalidated the detection performance via benchtests.

■ Vehicle Noise and Vibration

The Vehicle Noise and Vibration Lab conducts
research and development to improve riding
comfort and interior noise by reducing vibration.
It developed a new identification method to help
improve the precision of parameter estimation inorder to establish a method to simulate car body
vibration characteristics. It performed vehicle
dynamics simulation of a train set based on multibody dynamics, and found good conformity of thesimulation results with actual running data. By
applying displacement-dependent buffer rubber
as a link integrated with the yaw damper to reduce
the elastic vibrations caused by unbalanced massof the wheelset and by performing a running testof limited express vehicles, the level of riding
comfort was improved. To develop interior noise
reduction methods, the Lab investigated a methodof analyzing the transmission path of structureborne sound and proposed sound absorption
measures, such as the adoption of a suspended
floor structure in which a floor plate is suspended
from the side body structure or a ceiling panel asa concrete improvement method. A mechanicalpneumatic steering mechanism was installed ona wheel load decline reduction bogie in order toimprove the curving performance of vehicles. A
running test was conducted at the RTRI to confirm that the effects of this mechanism include
the reduction in the lateral force, prevention ofAnnual Report 2014-2015

counter-steering and reduction in squealing.

■ Vehicle and Bogie Parts Strength

The Vehicle and Bogie Parts Strength Lab conducts research on the evaluation of the strengthof car bodies and bogie components and on nondestructive inspection technologies. To improvethe crashworthiness of car bodies, the Lab carried out train collision simulations in the case of
a level crossing accident in order to consider the
impact acceleration inside a passenger vehicle,
and evaluated the degree of injuries to seatedpassengers by using these acceleration curves
as the input of simulation. The results clarified
that the integral of car-body impact acceleration
showed a strong correlation with the degree of
injuries to passengers in a collision. With a viewto making possible non-destructive inspection ofvehicle components, the Lab performed ultrasonic
testing and cross-sectional observation of thewelds of a diesel railcar’s propeller shaft, clarifying the relationship between the size of a defectand its defect echo. Based on these results, theLab proposed an ultrasonic testing method andinspection standards for propeller shaft welds forapplication in the periodic inspection of vehicles.
To evaluate the strength and reliability of axles
used in the conventional lines, the Lab performed
fatigue crack propagation tests using a full-size
axle. To develop methods to evaluate the strengthof welded joint structures in a bogie frame, theLab proposed new root-judgment-curved lines;
these curves can be used to determine the initiation of cracking from a weld root.

2

Vehicle Control Technology
Division

The Vehicle Control Technology Division consists of three laboratories: Traction Control, Drive
Systems, and Brake Control, which are primarily responsible for research and development,
consulting work and contract work on control and35

Research and Development

instruments; technologies to evaluate and reducerunning resistance and energy consumption, etc;
and of late, new circuit technologies, such as
hybrids, storage battery systems and fuel cells,
related to traction and braking railway vehicles.

■ Traction Control

The Drive Control Lab worked on the conversion of AC electric rail cars to battery powered
electric cars, electric rail car tractive effort
improvement control methods, simplification of inductive obstruction testing, AC car circuits basedon the characteristics of a new power device, anddeterioration predictions for the new device.
To convert AC electric rail cars to battery powered electric cars, the Lab introduced a method of
estimating high-speed charging of batteries andstorage battery voltage design guidelines basedon the results of analysis of data of a storage
battery powered electric car (test car).
To develop a tractive effort improvement control
method for electric rail cars, the Lab used a shunting locomotive to verify the practical applicabilityof the proposed traction motor control method(Fig. 4-2-1). In addition to this control method,a method of detecting wheel spin based on the
difference in the current of the traction motor of a
train set was introduced; throughrunning tests, theimprovement in acceleration and riding comfort
was verified.
To simplify inductive obstruction testing, theLab established test procedures for a DC railway
return current test permitting evaluation at maximum test speeds less than the maximum speed of
the vehicle. The Lab also clarified the occurrence
trends of noise according to test conditions.
The research on AC car circuits was basedon the characteristics of a new power device; inthis regard, a transformer-less AC car circuit that
ensures transmission of power and insulation
properties was proposed. Thus, the circuit was
built around a flying capacitor to reduce the sizeof the system. Its basic operations were confirmed
through a simulation.
The research on deterioration prediction for the
new power device included the verification of theappropriateness of a new thermal conductivity
analysis model accompanied by a test of the stateof generation of stress at a soldered connection

36

Figure 4-2-1 An employed control method for tractive effort improvement

based on the difference in the thermal contraction
between a board and a mounted device and thestart of long-term reliability evaluation.

■ Drive Systems

The Drive Systems Lab tackles challenges
such as basic research to develop a simulator forenergy evaluation to support energy saving efforts
and a monitoring method to diagnose the status ofengines, transmissions and other drive devices; toclarify the characteristics of fuel cell deterioration
resulting from long-term use; to lower the noise ofgear units; and to develop heat recovery systems
for diesel locomotives.
As a simulator for energy evaluation, the Lab
developed ground-level equipment and a train
operation simulator consisting of linked vehicles
and operation control. It developed a train performance calculation algorithm that reproduces thestandard running pattern of an operating train,
and it confirmed that the calculated train performance agreed closely with the typical runningof operating trains and that it conserved energy
to about the same degree as the average value
in past running results. As a drive device statusmonitoring method, the Lab proposed an abnormality detection method employing active band
analysis of vibrations; it was confirmed that the
prototype status monitor device (Fig. 4-2-2) candistinguish simulated abnormal engine vibrations
attributed to the operation of an air compressor.
Further, the Lab used transmission oil sampledfrom an operating train to ascertain that the sensor can effectively monitor lubricating oil, and also
demonstrated that the detector can effectively
distinguish large grain-size wear particles causedby an accident from normal wear particles.
Annual Report 2014-2015

Railway Technical Research InstituteVoltage signal
measurement unit

Power supply

Vibration acceleration
measurement unit

Signal process
recorderFigure 4-2-2 Prototype of the monitoring device■ Brake Control

The Brake Control Lab conducts research anddevelopment from the perspectives of structure
and control of Shinkansen and conventional line
mechanical braking systems.
Based on the work conducted on frictioninduced vibration generation mechanism andcontrol measures, the Lab clarified the phenomenon of brake noise caused by disk brakes andstudied preventive measures, demonstrating thatvibration of the frictional material of the lining withan even-contact pressure mechanism couples
with disk out-of-plane vibration, and brake noise
is radiated. The Lab prepared an even-contact
lining as a countermeasure, and evaluated its
performance by performing a full-size bench test,
verified that it achieved a maximum brake noise
reduction of 7 dB.
To find more efficient air brake methods, theLab attempted to reduce the stopping distance toimprove existing air brake systems by improving
response or by reducing air consumption to lower
energy use. To increase the response, a method
using a skid control valve, and thus reducing thetime constant of the brake cylinder pressure in
the air pipe system equivalent to an actual car bymore than 80%., is proposed. This proposed iscapable of lowering air consumption while maintaining high deceleration according to the resultsof a bench test and skid control test performed
using a hybrid simulator.

Annual Report 2014-2015

3

Structures Technology Division

The Structures Technology Division consists offive laboratories, namely, the Concrete Structures,
Steel and Hybrid Structures, Foundation andGeotechnical Engineering Structures, Tunnel
Engineering, and Architecture Labs, which areresponsible for enacting technical standards,
research and development, and consulting workand contract work related to structures. The
efforts to enact technical standards included a
study and preparation of the framework of draft
provisions to revise the Design Standards for
Cut-and-Cover Tunnels into a performance-based
design version. The Division conducted researchand development in the area of structure renewal,
condition monitoring etc. Further, a design
method and countermeasure work to prepare fortsunamis were conducted along with the researchand development including vibration control andseismic isolation technologies, and measures toimprove the safety of supplementary structures
such as catenary masts and station buildings,
considering an earthquake directly under Tokyo,
which is predicted to occur in the near future.

■Concrete Structures

The Concrete Structures Lab conducts research and development of technical standards
for concrete structures and is working on the
preparation of related manuals. It is also involved
in research on seismic reinforcement methods
and maintenance technologies. With regard
technical standards, the Lab verified maintenancestandards and studied effective countermeasures
to deal with the problem of exfoliation of concrete
structures. Through its research and development
work, the Lab has developed a seismic reinforcement method in which precast intermediate
beams are inserted in order to improve residual
capacity and restorability of RC rigid frame
viaducts, and large-scale renewal technologies
for viaduct structures. The Lab proposed initial
crack prevention countermeasures and a prediction method for long-term deformation of RC
structures, and clarified the wave force applied
to concrete girders by a tsunami and the girder37

Research and Development

outflow mechanism.

■ Steel and Hybrid Structures

For large-scale earthquakes

For long-term tsunami overflow

Adoption of a reinforced soil structure

Protecting embanked soil
with long flat reinforcing material

Geotextile(flat reinforcing material)

Simple slope work using a cement-improved

1:

0.5

Sandbags
gravelly soil slab
The Steel and Hybrid Structures Lab(Or welded metal screen)
prepares technical standards for steel and
1:1
Tsunamihybrid structures and conducts researchProtection of embankment
and development related to design,with long geotextile
maintenance, etc. Regarding technicalConcrete wall
Cement-improved gravelly soil slab
standards, the Lab has cooperated with theComparison with conventional method
Concrete Structures Lab for publishing the・Executable on small land space (normally, gradient from 1:1.5 to 1:1.8)
・High seismic resistance/tsunami resistanceDesign Standards for Steel and Concrete
Hybrid Structures, and Design Calculation
Figure 4-3-1 Highly tsunami-resistant reinforced embankment
Examples. It also supplemented theMaintenance Standards, and compiled the■ Tunnel Engineering
Manuals, which brings together information of
The Tunnel Engineering Lab performs research
use in maintenance work. Through its researchand development to enact technical standards
and development efforts, the Lab has proposed
and to provide maintenance technologies, derenewal technologies to improve functions ofsign methods, and construction technologies fordeteriorated viaducts by relocating their columns,
railway tunnels. To provide technical standards, itand has introduced a seismic evaluation method
conducts studies to revise the Design Standards
for existing steel pin bearings of steel bridges. For
for Cut-and-Cover Tunnels into performancemonitoring steel bridges, it has also developed
based design version. Development of design
technology for continuous long-term battery-lesstools for traverse structures under roadways
measurement of displacement of bearings using
has also commenced. The Lab has conductedvibration-based power generation.
research to develop a construction and design■ Foundation and GeotechnicalEngineering Structures

The Foundation and Geotechnical Engineering
Structures Lab conducts research and development work to revise technical standards related
to foundation and earth structures and to develop
soundness evaluation methods, lifetime extension
technologies for ground structures, reinforced soil
structures etc. Its technical standards achievements include revising the sheet pile foundation
design and construction manual, preparing adesign manual on seismic reinforcement method
for railway masonry walls with failure prevention
nets and soil reinforcements, and giving technological support to popularize the design manual.
Through its research and development work, it
developed a reinforced embankment resistant
to severe earthquake and prolonged overflows
caused by tsunamis (Fig. 4-3-1); it also developed
a rational soft-ground countermeasure method forembankment widening, a tunnel roadbed soundness diagnosis method and a structure statusmonitoring system for viaducts.

38

method for the connection between new andexisting tunnels as a large-scale renewal technology of underground station space (Fig. 4-3-2); it
has established a shield tunnel behavior analysis
method specialized for complex longitudinal structures and environments, technology to control
track irregularities caused by culvert propulsion,and a lining reinforcement method for mountaintunnels subject to earth pressure.
Responds to deformed section shape

Suitable for large-scale expansion

Proposed design method

Girder reinforced by hug-type inverted beam 

ts
resis
eam ection
ir
ent b
rcem udinal dfoin
Re e longit
in thVertical anchor
New tunnel

Exis

ting

tun

nel

Hor
izon
tal a
New
nch
or
in l and o
ate
l
d
ral
dire tunne
ctio ls in
teg
n
rate
d

10% lower construction costs than conventional method Figure 4-3-2 Construction method for connection between newand existing tunnels

Annual Report 2014-2015

4Power Supply Technology Division

The Power Supply Technology Division
includes three laboratories : Power Supply,
Current Collection Maintenance, and Contact Line
Structure Labs. They are in charge of researchand development, consulting, and contracted
work intended to stably provide electric power toelectric railways. In FY2014, the Division worked
on research and development challenges prioritising energy conservation, preservation and laboursaving. In addition, as part of the programme,
the Research and Development for the Future ofRailways developed a new electric power supply
system as an individual challenge to realize a lowcarbon society and the New Status Monitoring
and Preservation Technologies to achieve theindividual challenge of achieving continuous
monitoring of changes of the status of railway
equipment in the medium and long term.

■ Power Supply systems

The Power Supply Lab undertakes researchand development to improve the energy efficiency of railway power supply systems, reduce
Annual Report 2014-2015濛VXEVWDWLRQWRWDOPHDVXUHG VXEVWDWLRQWRWDOħFDOFXODWHG
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The Architecture Lab performs research anddevelopment to improve the safety, convenienceand comfort of stations. From the viewpoint ofsafety, the Lab is working on a seismic resistancediagnosis tool for platform sheds and a seismic
design tool for suspended ceiling of stations. The
pressure variation acting on movable barriers
when a conventional train passes through wasmeasured, confirming that a pressure variation
prediction method can be applied for high-speed
trains. To improve convenience and comfort, theLab has conducted a monitoring test for elderly
people, clarifying the talking speed for station
concourse announcements that is easiest tounderstand and thus, developing a method toimprove the audibility of loud-speaker announcements in stations for both elderly and younger
people. The Lab has also proposed a methodof converting existing elevated platforms into
platforms sheltered by a roof and walls.

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Substation power[km/h]

Railway Technical Research Institute

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simulator
and the measured values

equipment maintenance labour requirements,and enhance equipment protection. It improved
energy efficiency by developing a energy estimation of a train running simulator that links theelectric power, vehicles, and operation as part of
the Research and Development for the Futureof Railways and verified its calculation precision
through running tests of actual vehicles (Fig.
4-4-1). The results obtained by using naturalenergy to supply running power and by introducing a new DC high voltage feeding method
were summarized. To reduce labour required formaintenance, the Lab built a device that simplifies the on-site assessment of deterioration ofsurge arresters for DC feeders as part of Practical
Technology Development; a deterioration simulation transformer that will help evaluating the life of
substation equipment was also built. With a viewof improving the protection for the equipment, theLab conducted field testing of a substation earthing method intended to mitigate lightning damage,and also started revising protection methods andmethods of restricting the harmonics in invertercontrolled cars.

■ Current Collection Maintenance

The Current Collection Maintenance Lab
conducts research and development on preservative measures and overhead contact line
materials for current collection systems comprising overhead contact lines and pantographs.
As part of Research and Development for the
Future of Railways, it developed basic technologies to use images to inspect overhead contact

39

Research and Development

Z

Trolley line

Z

Coating resistancecontact pointrr
Coating resistanceContact strip

1550K

]

Hard copper
trolley line
Coating
resistancer

300K

Iron-based
sintered metal
contact strip

Figure 4-4-2 Trolley line – contact strip contact point temperature
distribution analysis

line equipment. As part of Practical Technology
Development, it studied estimation of the fatigue
lifetime of overhead contact line wire strands andimproving their fatigue resistance. Further, as partof Basic Research on Railways, it clarified thewear mechanism of current collection system
materials and evaluated the impacts of various
factors on trolley line frost formation.
To clarify the wear mechanisms of current
collection system materials, the Lab analyzed
the distribution of temperature of electric contact
points considering the surface resistance of trolley wire material and contact strips according totheir resistance and oxidation film (Fig. 4-4-2).
Based on the results, it mapped the relationship ofcombinations of trolley wire materials and contact
strips with the state of wear that varies depending on whether the two are welded or not, andconfirmed the adequacy of the relationship byperforming a wear test.

■ Contact Line Structure

The Contact Line Structure Lab performs research and development to improve the seismic
resistance of overhead contact lines and thecurrent collection process to prepare for higher
speed and to reduce the labour required forpreservation.
As part of ‘Analyze the Behavior of Overheat
Contact Lines During Earthquakes’, which
was performed as part of Practical Technology

40

Development, the lab newly constructed a simple
analysis model for the seismic resistance of sandfoundation for trolley poles that can represent
vibration properties based on detailed models
built in the past, and established indices for evaluating the seismic resistance under all imaginableequipment conditions for the Shinkansen. It also
proposed a practical evaluation method in which
procedures of the seismic resistant design guidelines can be applied and used easily by designers.
As part of Concrete Power Pole Replacement
Standards, it presented the deformation thattriggers the deformation of concrete poles andan assessment method along with a device thatcan easily confirm the neutral depth of covering
concrete. To clarify the temperature increase
and damage mechanisms of current collection
members, the Lab conducted a temperature increase simulation of the storage battery vehicle
charging equipment and proposed an evaluation
method. To reconstruct an overhead contract line
structure according to the lines, the Lab clarified
the behavior mechanism of a wear shape in trolley wires caused by the running of a high-speed
pantograph and proposed a method of mitigating
the impact on wear detection. As a Method of
Setting Wire Tension and Deviation of Overhead
Contact Lines for various kinds of tension adjustment devices, the Lab calculated the tension in
overhead contact lines and amount of variationin trolley wire height anticipated according to
its characteristics. The influencing factors andthe degrees of the impact of each factor werereported.

5

Track Technology Division

The Track Technology Division consists offour laboratories, namely, Track Structures
and Components, Track Structures andGeotechnology, Track Geometry and Maintenanceand Rail Welding Labs. They are responsible fortrack-related research and development, consulting work and contract work centred on improving
maintenance. In FY2014, the Division carriedout research and development for improving
maintenance and structures of tracks; the efforts
Annual Report 2014-2015

Railway Technical Research Institutewere focused on improving ballasted track and rail
maintenance methods and earthquake resistancecountermeasures.

Sleeper■ Track Structures and Components

The Track Structures and Components Lab
performs research and development of trackcomponents such as rails and rail fastening
systems that form tracks, turnouts, expansion
joints and continuous welded rail. Concerningthe ‘Impact of the State of Wheel-Rail Contact ofTransfer Parts of Turnouts and Expansion Joints
on Vehicle Dynamic’, the Lab performed vehicle
dynamic analysis using a section model thatsimulates rail grinding, confirming that there wasno remarkable variation of the state of wheel-rail
contact at transfer parts, variation of vertical andlateral load was small and that rail grinding has
a small impact on vehicle dynamic. To evaluate
the degree of rail gap when a long rail breaked
from the viewpoint of running safety, the Lab built
a vehicle dynamics simulation method permitting
the simulation of a train passing through a rail
gap and analyzed the slab tracks on the curve ofa Shinkansen line, confirming that it is possible
to mitigate the limit value of the gap. To study
the evaluation of the service lifetime of rails in
the high cycle range, the Lab obtained fatigue
data of rails over time with a cycle exceeding 2
million, confirming the possibility of extending rail
replacement standards.

■ Track Structures and Geotechnology

Track Structures and Geotechnology Lab
conducts research and development on directly
fastened tracks and ballasted tracks, roadbeds
of new and existing lines, embankment materials
and execution management, noise and vibration
countermeasures and the reuse of building andindustry by-products. To study the evaluation of
the lateral ballast resistance force during an earthquake on curves, the Lab conducted a large-scale
shaking-table bench test of a canted ballasted
track to and simultaneously evaluated the resultsof countermeasure work executed based on asleeper anchor and ballast curb wall (Fig. 4-5-1).
With the aim of increasing the efficiency ofballasted track repair work, the Lab developed
a work method using polymer to repair ballast
Annual Report 2014-2015

Ballast
Exc

itatio

n dir

ectio

n

Figure 4-5-1 Large-scale shaking table test of a ballasted track

containing fine particle soil and developed a steel
sleeper repair method using grout. To evaluate
the performance of a resilient sleeper ballasted
track, it developed a method that can use anelastoplastic constitutive model to quantitatively
measure the settlement of the sleeper caused bycyclic loading. To develop a simple track support
stiffness evaluation method, the Lab built a track
support stiffness evaluation test device capable ofloading an impact load equivalent to a train load.
To develop an evaluation method for slab filler
layer condition and to conduct repair work basedon on-train measurement data, the Lab proposeda method of appropriately removing a filler layer
damaged by frost damage and refilling it withmaterial with superior freeze-thaw resistance.

■ Track Geometry and Maintenance

The Track Geometry and Maintenance Lab
conducts research and development on track
maintenance methods, systems and machines
to raise up both train running safety and riding
comfort. In the research “ developing a model
to decide effective track maintenance plan usedLine section data
Track irregularity, inspection date data
Past maintenance data (measured＋predicted）etc.
Limiting conditions (Period MTTwork is possible, status of tracks) etc
Preparing representative data for each inspection date
Assessing seasonal variation in track change
Track change prediction (Maintenance plan use, rapid evaluation use）
※Probability predictions considering prediction errors
Calculating prediction parameters※Successively renewed by lot each time a plan is prepared

Preparing track change
Maintenance Plan (MTT, TT)

Track status(track irregularity advance,
State of ballast）diagnosis

Figure 4-5-2 Structure of a track irregularity maintenance planningsystem that can handle high-frequency inspection data41

Research and Development

The Rail Welding Lab conducts research anddevelopment on rail welding technologies, rail
head repair welding technologies, and rail-weldand rail non-destructive inspection technologies.
Working to simplify the rail gas pressure welding
process, the Lab simplified the rail end grinding
process and developed an automatic burnerswinging device to propose a gas-pressurewelding process that does not require a highly
experienced operator. With the aim of clarifying
the causes of the occurrence of internal defects
in thermit welds, the Lab incorporated the heattransfer phenomenon accompanying the flow
phenomenon and convection flow of molten steel
in a solidification analysis model built to quantitatively clarify the factors causing internal defectsof thermit welds. Thus, simulation precision was
improved.

6

Disaster Prevention Technology
Division

The Disaster Prevention Technology Divisionconsisted of three laboratories; the Meteorological
Disaster Prevention, Geo-hazard and Risk
Mitigation, and Geology Labs, which are responsible for research and development, consulting
work, and contract work concerning about mitigation of natural disasters caused by rain, wind,and snow, surveying and evaluation technologies
for ground and ground vibrations caused by the42■ Meteorological Disaster Prevention

The Meteorological Disaster Prevention Lab
conducts research and development activities on
methods of clarifying weather conditions, which
are necessary to take meteorological disastercountermeasures, and on methods of disasterrisk evaluation. To clarify the weather conditions,the Lab works toward improving the methodsof estimating temporal and spatial distributionsof meteorological elements based on meteorological numerical simulations; and, the Lab has
started to work on methods to estimate surface
rainfall at high resolution, using weather radar
data rainfall quantity using weather radar data.
In order to improve evaluation methods of safety
for vehicles running under strong winds, the Lab
classified kinds of damage caused by gusts andstudied methods to analyze temporal and spatial
scale quantitatively analysis methods. It has also
developed a model to quantitatively evaluate thetemporal and spatial representativeness of theobserved wind velocity obtained by anemometers
and the temporal and spatial correlation of winddirection and wind speed at two distant points.
With the aim of mitigating avalanche disasters, theLab has developed a numerical snowpack model,
estimation of volume of outflow from bottom of

Input voltage unit
Antenna(portable circuit)

Processor

Approx. 20cm

■ Rail Welding

running of trains. In FY2014, the Division workedon the following themes: Developing Disaster
Hazard Mapping Technologies and Developmentof Sequentially Evaluation Method of the Degreeof Danger of Disasters during Rainfall. These
themes are related to the future-oriented challenge, Improving Safety from Meteorological
Disasters. The Division built and proposed theDisaster Hazard Mapping System.

Approx. 80cm

with high-frequency measured track irregularity
data”, the Lab developed a track irregularity
maintenance planning system by applying suchmeasured data and diagnosis models for both
detecting rapid growth of track irregularity in shorttime and evaluating ballast deterioration (Fig.
4-5-2). Based on the results of a trial calculationby using the system, the obtained maintenanceplan was well considered actual track conditions. Moreover, in the research “Investigating
the mechanism for occurring rail corrugation”, theLab executed vehicle running simulation using a
multi-body dynamics analysis tool, which verified
the impact of the differences in support stiffnessof rails on the occurrence of the corrugation.

Power supply(for test use)
Avalanche pressure receiver

Transmitter

Detector (data processor)

Figure 4-6-1 Prototype of portable avalanche detector

Annual Report 2014-2015

Railway Technical Research Institute

Figure 4-6-2 Model test to clarify the scouring mechanism

snowpack model, and such other models forsnow cover on slopes. The Lab also developed
a portable type avalanche detector equipped with
piezoelectric elements (Figure 4-6-1). In order todevelop a method to plot a tsunami inundation
map, the Lab clarified that there are differencesin the two-dimensional and three-dimensional calculation results, and demonstrated that the causeof the differences was the method of calculationof the tip of the run-up.

■ Geo-hazard and Risk Mitigation

related to river disasters, it prepared an inundation analysis method for small-and-medium sized
rivers and used to create a model of drainage
equipment, thus clarifying its appropriateness. It
advanced the same model to develop a methodof applying it to the evaluation of inundationof urban areas. It has clarified the bridge pierfoundation ground scouring mechanism throughmodel testing (Fig. 4-6-2), thereby discovering
the changes in the physical properties of groundaccompanying scouring.

■ Geology

The Geology Lab conducts research anddevelopment on natural disaster hazard factor
abstraction and evaluation methods, large-scaleslope disaster evaluation methods, evaluationof geological factors concerning deformation oftunnels, prediction of the quality of water leachedfrom waste/surplus soil and ground vibration phenomena clarification and prediction methods. As
the result of natural disaster hazard factors, theLabs built a method to display hazards related
to different meteorological disasters on a single
system (Fig. 4-6-3). To develop a method of
evaluating large-scale slope disasters, it conducted a literature survey and a preliminary fieldstudy, revealed directions of the research. The
Lab also studied the evaluation of geological factors involved in the deformation of tunnels basedon rock tests and case analysis. To predict thequantity of water leached from waste/surplus soil,

Geo-hazard and Risk Mitigation Lab conducts
research and development for preventing or
mitigating slope disasters and river disasters. As
research on the prevention of slope disasters, theLab verified the suitability of a proposed method of
evaluating the disaster potential of slopes during
torrential rain and demonstrated the effectivenessof the method based on disaster cases. Further, it
performed model tests, obtaining
data to confirm the effectivenessof a method of restoring the
Input
Outputstrength of an embankment after
Factors/External forces
Hazard Evaluation Result
an earthquake had lowered its
Sallow slope disaster
Strong wind disaster
Topographical map
rainfall resistance. With the aim
Railway
Bare rock distributionof developing a bridge abutment
Evaluating
Relative hazard of
Recurrence interval of
possibility
backfill embankment cave-in
shallow slope collapse critical wind speed of
the train overturningofdisastercountermeasure, it performed aoccurrence
full-size embankment test to selectAvalanche disaster
Rock fall disasterWind direction and speed
suitable grout to form the optimal
Preciptation
solidified body. It also verified thesuitability of a method of evaluatPossibility of disaster
Probability of arrival
occurrenceof fallen rock massing destabilization trends of slopes
caused by thaw water based onfield observation data. Through reFigure 4-6-3 Input and output images for the hazard map
search and development on topics
Annual Report 2014-2015

43

Research and Development

7

Signalling and Transport Information
Technology Division

The Signalling and Transport Information
Technology Division consists of five laboratories: Signalling Systems, Train Control Systems,
Telecommunications and Networking, Transport
Operation Systems and Transport Planning andMarketing Labs. They perform research and development, consulting work, and contract work
related to developing and improving signallingand communication systems and equipment,
clarifying phenomena, improving evaluation
technologies, increasing efficiency and improving the convenience of transport-related work.
The experts from this Division also participate
actively in international standard discussions andactivities of academic societies.
In addition, as part of ‘Smoothing Movement at
Junctions’, which is a future-oriented challenge,
along the lines of themes related to the clarificationand evaluation of the status of cargo transport, theDivision systematized evaluation indices, and at
the same time, it developed a system to visualize
the effectiveness of the present measures andimprovement measures.

■ Signalling Systems

The Signalling Systems Lab works todevelop and improve signalling systems,
clarify causes of malfunctions, apply
image recognition technologies, andevaluate the service lifetime of signalling equipment. It has summarized thespecifications for system configurationand control logic intended to improvesafety based on level crossing using

44

independent on-board control and obstruction
detection by image sensors. In the future, its
functions will be evaluated using a prototype.
The Lab has also developed a method of performing calculations to predict the return current
distribution inside a station yard, permitting thecorrect setting of impedance bond capacity andcross bond location in order to reduce equipment malfunctions caused by return currents.
To evaluate the deterioration service lifetime ofthe signalling equipment, it conducted statisticalanalyses of the electronic components that havecaused malfunctioning of electronic interlocking
devices, abstracting the components that impact
the service lifetime of equipment.

■ Train Control Systems

The Train Control Systems Lab, by using
information communication technology, tries tomake safer train control systems, to reduce theground equipment of secondary lines, to evaluate
safety and reliability of signalling systems, andto provide design support for signalling systems.
For future systems, it has developed judgement
functions for intelligent trains; these functions
will help collect and safely control various sensing information on board. Along with operating
simulators, their functions have been verified. The
Lab has also developed a method that combines
inertial sensors with tachometer generators anda line feature database for on-board speed andposition detection. As for the system of secondarylines, it has developed a prototype of a system inwhich on-board equipment performs route control
without using a ground-based interlocking device
and confirmed its functions by laboratory testing(railway technology development subsidized by
Feeding voltage

Outward current

Returncurrent

Ground electric potential of the communication line (V)it built a model of pores in soil based on a literature survey, experiments, and trial calculations.
It created a basic model for the future study ofrigid-frame viaduct sections to perform a dynamic
analysis of ground vibration and confirmed thesuitability of the model. More, it classified the
reduction effects of countermeasures for vehicles
and tracks in against of ground vibration resulting
from an increase in the speed of Shinkansen andconventional lines.

350

Earth Current
Electro-magnetic
induction

Electric train
running

Electrostaticinduction

300

250

250

200

150
100

Rail

Data transmitter

Communication line

500Data transmitter

Induced voltage and induced current oncommunication line or rail

350

300

200
150
100
50

communication line kilometrage (km)Figure 4-7-1 Electromagnetic induction prediction simulator

Annual Report 2014-2015

Railway Technical Research Institutethe Ministry of Land, Infrastructure,
Transport and Tourism).

■ Telecommunications andNetworking③Station and its surroundings①Inter-city network

Drag coefficient

Bottleneck station

input
Quantifying and visualising
the resistance of movement
at a transfer㒔ᕷ㛫

Station and its surroundings②Intra-city
y network

R to M

The Telecommunications andBottleneck station
resistance to mobility(R to M)
Networking Lab works on telecommunication technologies such as
output
The calculated resistance towireless and wired communication
movement when walking ina station under the influence of
input
Number of passengers
and sensor networks, researches
surrounding passengers
Number of passengers
outputmathematical analysis and predicin bottleneck station
Advance evaluation
tion methods on structure monitoringof convenience
improvement effects
data to support maintenance work,
CASES
and develops evaluation methods
Figure 4-7-2 Evaluation of the smoothness of movement on a railway networkfor electromagnetic environments
on electric railways. It has proposed
disruption of the train traffic and a method of optistandard design approach for train radio systems
mizing calculations to reorder the train departureby using a 40-GHz band. It has also verified thatwith a computer system. To evaluate the number
it is possible to detect a person on a roadwayof cargo-handling machines or forklifts for a freightby using a 90-GHz band radar system (a chalstation, it developed a simulation method that
lenge invited from the public by the Ministry of
predicts the state of work by machines, permitInternal Affairs and Communications). To useting the estimation of the appropriate number ofthe monitoring data, it has determined the fundamachines.
mental conditions and proposed the introduction
guidelines for a network and database that are■ Transport Planning and Marketing
intended for use for a railway structure monitorThe Transport Planning and Marketing Lab
ing system. With regard to the electromagnetic
conducts
research and development themes
environments, the Lab developed a simulator to
related to the analysis of passenger’s decisionpredict dangerous voltage and noise induced on
making structures such as transport mode
telecommunication lines, rails etc. by electromagchoice behavior and route choice behavior andnetic induction phenomena (Fig. 4-7-1).
quantitative evaluations of services in stations.
To improve passengers’ mobility on railway net■ Transport Operation Systems
works, it has developed the evaluation method
The Operating System Lab develops methodsof smoothness of mobility with an overall viewof improving the efficiency and convenience offrom transport networks to stations (Fig. 4-7-2).
transport planning and traffic control. To ensure
To measure the non-market values generated bysmooth operation on railway networks, it has
maintaining and improving railways, it collecteddeveloped a method of simulating passenger
data on the non-market values of express trains
behavior when train operation is halted for several
operated in rural regions to study organizing andhours or more, permitting the prediction of theanalyzing the overall value system of railways. To
number of passengers who will queue up in adevelop a method of flexibly setting for reserved
station. To provide methods of train reschedulingseats and unreserved seats in an express train,
operation according to passenger flow, it clarified
it analyzed data such as estimation report of ridthe objective levels of toleration for reschedulinging passengers, express train surveys and pastof the dispatchers and the degree of reschedulingsales record of reserved seats; using these data,that will result in strong dissatisfaction among pasit built a method of estimating potential passenger
sengers. In addition, it built a method of estimating
demand by seat type (reserved seats/unreserved
the probability that passengers will select the firstseats).
train after the resumption of operation following a
1

Annual Report 2014-2015

2

3

45

Research and Development

8

Materials Technology Division

The Materials Technology Division consistsof five laboratories, namely, Concrete Materials,
Vibration-isolating Materials, Lubricant Materials,
Frictional Materials, and Applied Superconductivity
Labs. They are responsible for research anddevelopment, consulting work and contract work
concerning railway materials, and also for searching, introducing, researching and evaluating theenvironmental impacts of various new materials.
In FY2014, the division conducted researchand development to develop advanced materials
and clarify their deterioration mechanisms in order
to apply the specific achievements that can meetthe needs of railway operators.

■ Concrete Materials

The Concrete Materials Lab conducts research
to improve concrete structure maintenance technologies, build durable concrete buildings anddevelop new materials. It clarified that measuring
the initial hydrogen ion density (pH) of hardened
concrete is an effective way of evaluating thealkali-silica reactivity of concrete. To clarify the
impact of sulfates on deterioration, it studied
conditions such as initial curing temperature
and water content caused by Delayed Ettringite
Formation. It also carried out research to clarify
the impact of water on concrete deterioration andthe relationship of mix proportion and properties
in a hardened geopolymer body and to develop
a simple method of evaluating the quality of thesurface of concrete surface.

■ Vibration-isolating Materials

The Vibration-isolating Materials Lab conducts
research and development of new materials
related to rubber and resin type materials usedby railways and investigates evaluation methods
for their performance and durability evaluating
methods for their performance and durability. As
part of structure-related work, it collected data tobuild a life-cycle cost (LCC) evaluation method
for repainting steel structures in corrosive environments; it also developed wind-load reduction
type soundproofing that will permit large increase

46

Table 4-8-1 Comparison of the low-temperature fluidity between current
and RTRI-developed gear oil

Current oil

RTRI-developed
gear oil

Viscosity index (VI)*1

105

154

Pour point (℃)*2

-32.5

-40.0

*1...Index for change in viscosity according to temperature(The higher the VI, the lower the increase in viscosity due todecrease in temperature )*2...Lowest temperature at which oil remained fluidin the height of existing structures. With regard
vehicle-related work, it studied piezoelectric rubber, which is flexible and can be moulded freely,
to evaluate the durability of materials applicablefor foreign object detection sensors for the sliding
doors installed in a vehicle. In order to reduce
vehicle weight, It also investigated an evaluation
method of the degradation of plastic windows andmanufactured a prototype of resin products.

■ Lubricating Materials

The Lubricant Materials Lab conducts researchand development of bearings and other machinecomponents that play a part in the running ofvehicles and of lubricant oils and greases thatmaintain their operation. As part of the work ongear oils for Shinkansen vehicles, it developed agear oil that restricts the increase of costs and has
low-temperature fluidity permitting the operationof gear units stably at -30°C (Table. 4-8-1). The
Lab used a newly devised lubrication properties
evaluation method to discover the possibility of
improving lubrication performance by composite
copper plating the retainers. To evaluate the applicability of nanocarbons, it carried out performance
evaluation of electric conductive grease for bearing use and studied its applicability to pantographcontact strips; thus, the Lab identified the challenges in the practical use of nanocarbons.

■ Frictional Materials

The Frictional Materials Lab conducts researchand development to boost functionality andperformance of railway components involvedin tribology phenomena, including friction andwear; clarifies the mechanism of damage these
phenomena cause; and develops new metallic

Annual Report 2014-2015

Railway Technical Research Institutematerials. The Lab has studied the applicationof compressive and tensile loads to actual rails
and measured their stress with X-rays in order toappropriately manage axial force of rails; it confirmed that there is a correlation between negative
load and the X-ray stress measurement results.
It measured the state of contact when reciprocating motion was repeated with the wheels andrails in contact, confirming that it is possible toquantitatively evaluate the change in the state ofcontact accompanying cyclical contact. Its workon new metallic materials included verification of
the possibility of creating practical products using
fire-retardant magnesium alloys.

■ Applied Superconductivity

To apply high-temperature superconductive
material to railways, the Lab set up a 300-mclass superconducting feeder cable on the test
line at the RTRI (Fig. 4-8-1) , confirming its power
supply performance and cooling performance;then tested the running of the train. To develop
high-temperature superconducting materials, it
developed RE-type bulk material, configured acompact superconducting magnet for use in material analyzers and designed a magnetic correction
technology using a shim coil. It developed bulk
materials of MgB2, which is a new material; atthe same time, it investigated processing technology, focusing on its application, and successfully
processed the material to form diverse shapes.

9

Railway Dynamics Division

The Railway Dynamics Division consists offive laboratories, namely, Vehicle Mechanics,
Current Collection, Track Dynamics, Structural
Mechanics, and Computational Mechanics
Labs. This Division is responsible for research
on clarification of dynamic phenomena caused
by interactions between vehicles, tracks andstructures, pantograph and overhead contactlines, wheels and rails, and so on, aiming todevelop improvement strategies for preventionof deterioration due to such dynamic phenomena.
In FY2014, the Division built the core system of
the railway simulator, developed the bogie for theprevention of flange climb derailment and so on.

■ Vehicle Mechanics

The Vehicle Mechanics Lab conducts researchand development related to the safe running ofvehicles. The Lab proposed a control to decrease
the wheel load of a bogie that follows the twistingof tracks as an attempt to develop a new type ofbogie for the prevention of flange climb derailment (Fig. 4-9-1). A hunting motion limit test of
the bogie was conducted on the test rig to confirm
its running safety. Line tests were also performedon the RTRI test line to confirm running safety
improvement effects in low-speed range at theexit of a high degree curve and at a turnout.
These test results show that this bogie ensures
the running safety at a speed up to 130 km/h on aconventional line, and the wheel load decline canbe reduced by 40% at the exit of a high degreesole bar

Figure 4-8-1 Installed 300-m class superconducting feeding feeder cablecross barsole bar rotation direction
Figure 4-9-1 Schematic of new type of bogie for the prevention of flange
climb derailment by suppressing the decrease of the wheel load

Annual Report 2014-2015

47

Research and Development

curve with a radius of 160 m, cant of 90 mm, anda reduction factor of 400 times. In addition, by
expanding the scope of application of the existing
wheel load lateral force estimation formula andby introducing new models such as bogie rotation
moment based on bogie rotation resistance andlongitudinal creep force between wheels and rails,
the Lab. confirmed that it is possible to evaluate wheel load lateral pressure with the desired
precision on a high-degree curve without a cant,in addition to the conventional high-degree curve
decelerating running conditions.

■ Current Collection

The Current Collection Lab conducts researchon dynamic behavior prediction methods,
equipment status monitoring methods for the
pantograph and overhead contact lines systemand the aerodynamic phenomena related to highspeed pantographs. The Lab proposed a methodof improving the HILS system of pantographs andconfirmed its effectiveness by a simulation. To
develop an equipment status monitoring method,
it verified the effectiveness of a method of estimating the static height of the overhead contact
wire based on the contact force and pantographheight. It also developed a prototype of a newmeasuring equipment to monitor any abnormality
in pantographs and confirmed its effectivenessby a commercial line test. It also clarified the lift
variation mechanism of pantographs caused by
the wear of contact strips, etc., by performing windtunnel testing and numerical calculations.

■ Track Dynamics

The Track Dynamics Lab conducts researchand development activities on ballasted track
deterioration, rail damage, wheel/rail adhesion
and lubrication. The Lab developed an elastic
Quadruple Discrete Element Method (QDEM)
program and built a ballasted track model that
reproduced the detailed structure of each ballast,evaluating the settlement of tracks accompanying
the elastic vibration of the ballasted track androtation and movement of the ballast during thepassage of a train (Fig. 4-9-2). As a method of
measuring axial force of rails based on detectionof the natural frequency, it proposed a correction
method considering scattering of the fastening

48

Figure 4-9-2 Ballast behavior analysis based on QDEM

interval on site, wear of the rail head, and thetemperature characteristics of the fastenings
elasticity. To consider rail damage, it built a rail
damage evaluation method based on conflict
analysis of initiation and propagation of short
cracks and of wear.

■ Structural Mechanics

The Structural Mechanics Lab builds original
simulation and analysis technologies, measurement evaluation technologies etc., and uses thesetechnologies to conduct research to improve
running safety and to advance the design andmanagement of structures. The Lab developed
a rock slope stability evaluation system basedon remote non-contact measurements in orderto prevent the damage to railway by rockfall fromtrackside slopes along railway lines. The vibration
data of a target rock block is obtained by the infrared LDV type non-contact vibration measurement
system and the rock shape is measured by theaerial survey system which is a drone equippedwith a stereo camera. The rockfall risks of therock block under both normal conditions andan earthquake are evaluated by the numericalanalyses using those data. In the research on
the design and maintenance of existing concrete
structures, it constructed a numerical simulation
model capable of precisely evaluating the influence of raising train speeds, and of increasing
weight and stiffness and clarified the influenceof various parameters on the impact coefficient.
It proposed an autoregressive spectrum (ARS)
method to identify the natural frequency of structures with high precision based on the residual
waveform after the passage of a train.

Annual Report 2014-2015

Railway Technical Research Institute■ Computational Mechanics

The Computational Mechanics Lab built awheel-rail rolling contact analysis method basedon the large-scale parallel finite element method
to clarify the phenomena of wear and cracking on
wheels and rails. It modelled rail joint depressions,2-axle 2-wheel multiple wheel sets, slab tracks,etc., permitting more realistic analysis. In order
to allow the deterioration analysis of ballasted
tracks, the Lab developed an interface to perform
computations linked with the motion analysis ofballasted track based on the elastic Quadruple
Discrete Element Method. The Lab built a methodof evaluating the behavior of contact surfaces
mediated by water films, oil films, etc. based on
an analysis coupled with FEM and the particle
method. This can reproduce water film behavior on rail surfaces. To optimize the structureof vehicle bodies, it built a single vehicle bodymodel, performed stress analysis, and studied
the application range of a press-moulded bodyfor structural members.

10

Environmental Engineering
Division

The Environmental Engineering Division consists of three laboratories, namely, the Vehicle
Aerodynamics, Heat and Air Flow Analysis, andNoise Analysis Labs. They are responsible forresearch and development, consulting, and contract work concerning wayside environments andaerodynamic phenomena. In FY2014, it tackled
challenges related to the wayside environments
and safety, etc., including the future-oriented challenge, ‘Evaluation /Measures to Preserve Wayside
Environments for High Speed Operation’.

■ Vehicle Aerodynamics

The Vehicle Aerodynamics Lab works on aerodynamic problems related to the aerodynamic
characteristics of railway vehicles.
In order to clarify the aerodynamic characteristics of railway vehicles under cross wind, it
performed wind tunnel tests using a running modelof a commuter-type train and those using a static
model in compliance with European standards. It
evaluated the impact of coastal topography andAnnual Report 2014-2015

Wind:90°

Figure 4-10-1 Numerical simulation of the flow around a 3-vehicle train
installed at a single-line

wind barrier on the aerodynamic force acting on
railway vehicles. Also, it performed a numericalsimulation to reproduce the wind tunnel tests (Fig.
4-10-1).
Regarding turbulent flow field and aerodynamic
forces around a vehicle, it carried out field tests toclarify a distribution of under-floor flow velocity ina travelling direction and conducted wind tunnel
tests to develop practical measures to reduce air
resistance. It performed numerical fluid dynamic
simulation related to vehicle lateral vibration intunnels, clarifying the mechanism of occurrenceof pressure fluctuation on vehicle body sides.
Regarding the development of air flow andaerodynamic noise simulator, it performed largescale calculation of an overall pantograph modelusing the K Supercomputer and confirmed thatthe calculation results agree closely with the windtunnel test results.

■ Heat and Air Flow Analysis

The Heat and Air Flow Analysis Lab works on
aerodynamic phenomena related to railways:
pressure waves and thermal environment inside
tunnels caused by trains travelling through thetunnels, and the hot-gases flow during a tunnel
fire.
In order to reduce the micro-pressure wave
(tunnel sonic boom) for higher speed operation,
it evaluated the performance of an extremely
long tunnel entrance hood and studied a countermeasure applied inside a tunnel in the processof compressive wave transmission and that applied at the tunnel exit using a hood with inside
partitions. Those were achieved through field49

Research and Development■ Noise Analysis

The Noise Analysis Lab works to clarify andpredict railway wayside noise and to develop
countermeasures.
It performed field measurements using a
microphone array to clarify the unsteady anddirectional characteristics of the sound sourcesof Shinkansen vehicles. It performed field measurements to investigate noise distributions in
a cut section along a Shinkansen line, and alsostudied a method based on an acoustic model test
to simulate the acoustic characteristics in the cut
section. It also performed numerical calculations
using the time domain finite difference method toinvestigate the impacts of multiple reflections ofsound between vehicles and sound barriers along
viaducts. Based on the results of measurementsof wayside noise around overbridges and on the
results of calculation by the prediction method, itevaluated the impact of an overbridge on waysidenoise.
Regarding the aerodynamic noise, it conducted
model tests in a large-scale low-noise wind-tunnel
to evaluate the impact of bogie conditions on
aerodynamic noise quantitatively (Fig. 4-10-2).
It investigated the pressure fluctuation in open
sections by performing field tests in flat andembanked sections and clarified the propertiesof pressure fluctuation caused by aerodynamic
phenomena. With regard the phenomena causedby structure vibrations of pressure fluctuation, it
improved the precision of the numerical analysis
method and investigated the impact of parametersof vehicles and tracks.

50

Side cover

Status during noise measurement①Standard conditions②No bogi③No wheels and bogie

Sound pressure level difference dB

measurements, model experiments, and numerical simulations.
Regarding the thermal environment inside tunnels, it compared testing by the results of modelexperiments under simple conditions without
spring water with those of the corresponding
numerical simulations, confirming the accuracyof the simulation.
To improve the predictions of the flow of hotgases during a tunnel fire, it investigated theimpact on the results of modelling tunnel wallboundary conditions and the fire sources byperforming sensitivity analysis using a general
purpose CFD code.

② ①

5

③ ①
0

-5

-10

125 160 200 250 315 400 500 630 800 1000
1,000 1250
1,250

1/3 active band frequency (in real scale) Hz
Figure 4-10-2 Impact of bogie conditions on aerodynamic noise(with side covers during measurement in cases ①, ②, and ③)

As part of the research and development tasks
on structure-borne sound, the Lab clarified thephenomena of impact sound at rail joints andhigh-frequency sound above 10 kHz on curves.
It also clarified the influence of the joint conditionon the impact noise and the contributions of rail,
wheel and sleeper to the total impact noise. It
studied high-frequency sound by performing fieldtests on curves, thus, evaluating the contributionof rail noise to the total noise at frequencies
above 10 kHz.

11

Human Science Division

The Human Science Division consists offour laboratories, namely, Safety Psychology,
Ergonomics, Safety Analysis, and Biotechnology
Labs, which are responsible for research anddevelopment on human factors to contribute to
the improvement of the safety and comfort ofrailways. In FY2014, it carried out research on
the prevention of human errors, education andtraining, train operation aptitude tests, train operator support, skills for coping with accidents andmalfunctioning, in-car comfort, support for safety
management, and utilisation environment. It also

Annual Report 2014-2015

Railway Technical Research Instituteprovided technical guidance for train operation
aptitude tests and supported safety activities ofrailway companies.

■ Safety Psychology

The Safety Psychology Lab develops training
methods to prevent human error. It also develops
and guides train operation aptitude tests.
To prevent human errors, it confirmed the effectiveness of double-checks and safety patrols
through various some experiments, and proposed
detailed endorsement procedures. And it also
proposed endorsement procedures for use when
preparing manuals. To share the information of
the original measures with other work places, it
proposed a design of a “safety measures sharing site”. And in order to encourage personnel
to report their own mistakes voluntarily, it clarified four encouragement factors by conducting
a web survey and psychological experiments; italso proposed educational and training methods
applying these factors.
Regarding technical guidance for train operation aptitude tests, it held lecture meetings forprivate railway companies hosted by the RTRI,
giving lectures to about 360 individuals fromprivate railroad operators and district transport
bureaus of the Ministry of Land, Infrastructure,
Transport and Tourism.

■ Ergonomics

The Ergonomics Lab conducts research anddevelopment on methods of deciding sounds ofwarnings and alert inside train cabs, driver support methods, the improvement of passenger
safety, the provision of information to passengers
in the event of an accident, and improvement of
comfort inside cars.
It proposed a method of deciding sounds ofwarnings and alert inside train cab, based oninterviews and questionnaire survey that train
operators participated in (Fig. 4-11-1) It alsostudied methods of providing information in theevent of malfunctions, and installed a support
system that reflects the results of the study on adriving simulator.
To develop a safety assessment method in theevent of a train collision, it performed physical testof impacts and numerical simulation, clarifying theAnnual Report 2014-2015

Danger Danger
level
level

Dangerlevel

Dangerlevel

Sweep soundIntermittent soundTrain protection radio

Interchanged soundATS operation

Continuous sound(saw tooth wave)
Continuous sound(chopping wave)
Single sound(including 2 sounds)

Pattern approaching

Voice

Stopping station

Low

Alert level

High

Figure 4-11-1 Announcements and alert sounds for evaluation andresponse to danger level

relationship between the acceleration pulses andseverity of passengers’ injuries. It prepared an
educational video to improve employees’ ability
to give guidance on adapting to circumstances inthe event of a disruption of the schedule.
To obtain data needed to predict thermal comfort inside vehicles more precisely subject tests
were performed. To study the effect of the heightof the centre of roll of a tilting train on the passenger comfort, subject test with the Ride Comfort
Simulator and theoretical analysis of accelerations
worked on passengers were conducted, whichfound that the height of the centre of roll has no
substantial effects on passenger comfort under
the condition of the height of the centre of roll from0 to 150 cm above the vehicle floor.

■ Safety Analysis

The Safety Analysis Lab helps railway companies evaluate railway risk and improve safety.
It has summarized items that should be
implemented to correctly and smoothly transmit
information to recipients, including the risk in tense
situations such as malfunctions affecting dispatch
work, and has developed training methods to be
used to teach appropriate communication technologies.(Fig. 4-11-2) It has confirmed that suchtraining boosts the awareness of the need forcommunication technologies and improves theexecution of normal work. It studied a method ofusing near-miss information for risk assessment.
To support activities to improve safety of railway
operators, it provided technical guidance on the‘RITR type human factor analysis method’ and the51Research and Development

Reflecting on conditions
during experience of scenarios
Awareness-raising
Reflecting on normal work
Confirming degree of execution
Feeding back results of training

Do they usually implement it?

1 or 2 months

Are they aware of importance?

Experiencing malfunction
cenariosVideo
recordingPrecautions concerning communication technologie

Explaining purpose of training
Awareness-raising

Figure 4-11-2 Malfunction event communication training method‘hearing investigation technique to analyze thebackground factors of an accident’ and conductedsurvey research on ‘methods of analyzing thesafety climate of workplaces’.

■ Biotechnology

The Biotechnology Lab works to evaluate
short-term impacts of magnetic fields on livingorganisms, to clarify causes of and improve
unpleasant odors, and to identify measures toreduce the problems with wild animals.
To investigate the effect of magnetic fields onnerve stimulation in detail, It developed a timevarying high magnetic field exposure device that
can intermittently expose nerve cells to a magnetic
field of 0.4 T in 200 Hz. To clarify the causes of
unpleasant odors, it found that mold, which is one
cause, grows more easily if the humidity in a room
exceeds 70%. To study measures to reduce train
collisions with wild deer, it investigated the effectsof various kinds of sounds on domesticated deer
and wild deer, revealing that the degree of thereaction and degree of habituation varies according to the type of sound.

12

Maglev Systems Technology
Division

The Maglev Systems Technology Divisionconsists of two laboratories, namely, theElectromagnetic Systems Laboratory, the52

Cryogenic Systems Laboratory, and the
Yamanashi Maglev Test Center, which are responsible for basic research on superconducting
magnetically-levitated transportation (Maglev)
systems. They also conduct research on the application of technologies created by research anddevelopment of Maglev systems (superconducting technology, cryogenic technology, linear motor
technology) to conventional railways, manage theassets of the Yamanashi Maglev Test Center, andcarry out contract testing work. As part of basic
research on Maglev systems, the Division has
worked on vehicle dynamics analyses, madeefforts to reduce the cost of introducing newtechnologies to superconducting magnets andground coils, and researched equipment diagnosis technologies for commercial lines. As part ofresearch on application to conventional railways,
the Division has developed non-contact power
supply technologies, linear-motor-type eddycurrent rail brakes, and flywheel energy storage
systems for railways using superconducting
magnetic bearings. The total distance traveledby the Maglev vehicles in the long-term durability
tests on the entire 42.8-km track in the Japanese
fiscal year of 2014 of 218,217 km (about 2.5 times
the greatest total distance recorded on the priority
section) in a total of 206 testing days were thegreatest number of vehicle-running days and thegreatest total distance traveled by the Maglev
vehicles in any single year. With the contributionof this annual record, the cumulative Maglev vehicle running distance on the entire 42.8-km trackexceeded the 1.2 million km cumulative vehicle
running distance on the priority section.

■ Electromagnetic Systems

The Electromagnetic Systems Laboratory conducts research on vehicle dynamics and groundcoils of Maglev systems, and the development oftechnologies such as non-contact power-supply
technologies for vehicles, conventional railway
vehicle magnetic field evaluation methods, andlinear-motor-type eddy-current rail brakes for
Shinkansen. Researchers of vehicle dynamics
computed characteristics of electromagnetic
forces and vehicle dynamics for proposed casesof Maglev vehicles equipped with onboard rareearth high-temperature superconducting magnets,
Annual Report 2014-2015

Railway Technical Research Institute

Test train
500mm

Generator coil
(Vehile)1070mmRailPower supply coil
(Ground)Figure 4-12-1 Non-contact power supply systemand confirmed proposed conditions that will improve vehicle characteristics to benefit Maglev
operation. Researchers of ground coils built anexperimental non-contact inspection system
to diagnose insulation properties of propulsion
coils and cables which are special high-voltage
devices, and verified its basic performance. In
addition, lab members closely investigated thebenefits of resins for use in the ground coils for the
propulsion system made by blending core-shellresins, and performed resin-melting tests basedon a normal-pressure melting method, as partof research on the possibilities of recycling usedground coils. To build a non-contact power supply
system for vehicles, researchers used coils they
designed to perform 50-kW class total power supply tests using an R291 test vehicle on the RTRI
test track. The results confirmed that the system
could provide a stable supply of electricity whilethe vehicle was running as well as when it was
stationary, and could operate as a power-supply
system on board the vehicle (Fig. 4-12-1). To
develop a method of evaluating a conventional
railway vehicle’s magnetic field, the researchgroup built a prototype of an analysis tool for railway cars whose magnetic fields fluctuate greatly,
and also connected magnetic field measurement
instruments to build a system that can perform
integrated analysis and evaluation based onrecorded data. To develop a Shinkansen linearmotor-type eddy-current rail brake, researchers
designed and studied armatures.

■ Cryogenic Systems

The Cryogenic Systems Laboratory develops

Annual Report 2014-2015

Figure 4-12-2 Full-size high-temperature superconducting coilfor levitation-type railways

high-temperature superconducting magnets forMaglev systems, and develops flywheel energy
storage systems for railways using superconducting magnetic bearings. As part of the work on
high-temperature superconducting magnets, thelab members proposed a method of producing
rare-earth type high-temperature superconducting
coils that prevent the deterioration of conductivity
performance, constructed a full-size high-temperature superconducting coil (Fig. 4-12-2), andperformed cooling tests, confirming that the coilhas good conduction cooling performance, coldstorage performance, and conduction capacity.
Furthermore, a cooled vibration test confirmedthat the structure of the full-size coils does notcause any problems in basic deformation modes.
To develop a flywheel energy storage system,
researchers created a detailed design of a demonstration machine for a grid-connected test
linked to a photovoltaic power generator, andbuilt superconducting magnetic bearings, magnetic fluid seals, guide bearings, and other basic
components, and completed a demonstration
machine with an output of 300 kW and capacityof 100 kWh. Lab members also designed a control
device for the grid connected test and studied
ways to increase the output of the motor generator. In addition, with the aim of developing an air
conditioner based on magnetic refrigeration, thegroup experimentally confirmed that concurrently
using a few different magnetocaloric materials
with different operating temperatures results in an
increase in the differences in the cooling temperature. The researchers also performed a heat-cycle
numerical analysis considering the heat loss inorder to determine the possibility of establishinga kW-class magnetic refrigeration system.

53

Research and Development

13

Center for Railway Earthquake
Engineering Research

The Center for Railway Earthquake Engineering
Research consists of three laboratories,
namely, Seismic Data Analysis, Soil Dynamics
and Earthquake Engineering, and Structural
Dynamics and Response Control Labs, which
are responsible for earthquake-related researchand development consulting work and contract
testing work.
In FY2014, considering the possibility of anearthquake occurring directly under Tokyo or ahuge subduction-zone earthquake, which are
now feared to be imminent, the Centre worked on
soft-countermeasure technologies by developing
an early earthquake alarm system and proposing
an instantaneous tsunami estimation method. It
also conducted research and development on
hard countermeasure technologies, for example,
by proposing new structures and mechanisms
such as a liquefaction prevention method withvine-like ground improvement, a super-connectedfoundation viaduct or a negative stiffness damper.
The Centre also verified the precision of the railway earthquake disaster simulator, which wasbuilt as a tool in the event of an earthquake toquickly hypothesize the kinds of potential disasterrisks and their locations, confirming the practicality of the simulator.

■Seismic Data Analysis

At seaSea bottom
seismograph data
(Continuous wave form )On landInformation for alarms(Index/quality control information)
Railway company

Undersea cableSea bottom seismographIndex calculation
Quality control
information

Alarm decision

Figure 4-13-1 Alarm processing flow when using sea bottom seismographand communication specifications to permit theuse of sea bottom seismograph data to provide
railways with early warnings (Fig. 4-13-1). As partof research on huge earthquakes, the Lab proposed a method of predicting tsunami waveforms
near shorelines by applying observed tsunami
waveforms and tsunami propagation properties, coastal tsunami height prediction method
incorporating small-scale tsunami simulations,and a method of estimating earthquake motion byconsidering the extent of faults and local groundamplification. To estimate earthquake motion andearthquake damage with high precision, it has
begun to perform highly concentrated earthquake
observations and to explore underground structures along railway lines.

■ Soil Dynamics and Earthquake
Engineering

The Soil Dynamics and Earthquake Engineering
Lab conducts basic and applied research on the
ground behavior against earthquakes everythingfrom the basic properties of earthquake motion
to its impact on the ground when an earthquake
occurs and also establishes seismic design standard. In order to evaluate the behavior during anearthquake, it developed an earthquake damage
simulator in cooperation with other concernedlabs. It has developed a new method of efficiently

The Seismic Data Analysis Lab undertakes
research and development to improve early
earthquake warning capabilities, to provide instantaneous predictions of tsunamis and strong
earthquake motion when a large earthquake
occurs, and to estimate earthquake motion anddamage with high precision inorder to achieve early restoration
Residual deformation
indicationof railway services. With the aim of
improving early earthquake warning capabilities, the Lab developed
a seismograph that incorporates
Damage display capablea new P-wave based earthquakeof confirming damage location
Shear failure indicationand degree of damage
specification estimation algorithm
Direction of progress
and a noise discrimination method.
It proposed a processing method
Figure 4-13-2 Example of the results of an earthquake damage simulation

54

Annual Report 2014-2015

Railway Technical Research Institutemodelling both ground and structures in order toeasily make predictions over a wide area and amethod of appropriately visualizing the results
obtained by this new method (Fig. 4-13-2). It
has also worked to improve the applicability ofthe simulator. It has also verified the simulator
by using actual seismic damage cases to showthat the results provided by this simulator are
extremely precise.

friction is manifested at the same time as when
the friction causes damping during an earthquake.
The Lab confirmed that this can reduce stiffnessof an overall structural system, and that on arigid frame viaduct with normal specifications,the device can reduce absolute displacement byas much as 20%.

■ Structural Dynamics and Response
Control

The Structural Dynamics and Response Control
Lab works to clarify phenomena of the seismic
behavior of structures, power poles, vehicles etc.
and develops sophisticated methods to evaluate
their behavior. It has conducted research anddevelopment of seismic design methods andseismic retrofitting work methods. To evaluate
the behavior of structures, it has measured thedamping constants of about 90 railway structures
to clarify their properties. It also clarified the factthat the damping properties of a structure are
more strongly correlated with its natural frequency
than with its structural form to propose a damping constant evaluation method. Based on the
research on seismic retrofitting, it developed anegative stiffness friction damper as a new seismic isolation device. As shown in Figure 4-13-3,
this device is so constructed that by using a gas
spring to cause high pressure contact of a convex
plate and sliding material, the stabilized negative

652mm

Direction of motion

Gas spring
Sliding material
䠄PTFE)

1780mmConvex sliding plate

Figure 4-13-3 Negative stiffness friction damper

Annual Report 2014-2015

55

Report on Key Activities under the Previous
Master Plan RESEARCH 2010

1

Executive Summary

The Railway Technical Research Institute(RTRI) steadily carried out the master plan RESEARCH 2010 – for five years after fiscal 2010
and accomplished most of expected purposes
while carrying out related R&D activities and otherbusiness activities and operations.
In tackling this R&D, RTRI set up the “objectives of R&D” to indicate the direction of R&D andthe “pillars of R&D” to specify R&D themes tofocus on. RTRI concentrated its efforts on further
sophistication of simulation technology as a challenge in a new field.
During the period of RESEARCH 2010,
Japan happened to suffer the Great East
Japan Earthquake and some local heavy rains.
Consequently, the public came to have stronger
awareness of security and safety as well as
energy issues, which lead to the change in theenvironment surrounding the Japanese society
and railways. To cope with this change, RTRI
aggressively tackled R&D activities related
to earthquakes and other large-scale natural

2

Business Activities

2.1

Public interest services

2.1.1 Research and development

RTRI defined as its R&D objectives“Improvement of Safety,” “Harmony with
the Environment,” “Cost Reduction,” and“Improvement of Convenience.” To pursue theseobjectives effectively while preventing dispersionof limited resources, the Institute set up threepillars as specific targets: “R&D for the future of56

disasters as well as energy issues.
In addition, as overseas deployment ofJapanese railway technologies has gathered momentum, RTRI’s Railway International Standards
Center has intensified activities aimed at proposing international railway standards prepare by
Japan. Simultaneously RTRI promoted joint
research with foreign research institutes anddispatched its researchers to the counterpart
organizations.
As an example of RTRI’s management efforts,
since RTRI became a public interest incorporated
foundation on April 1, 2011, the Institute has been
exhaustively improving operation under a new
management system, intensifying compliance,
fostering human resources, and upgrading andrenewing test equipment.
RTRI has formulated a new vision that clearly
indicates its ambition and direction toward thefuture and a new master plan – RESEARCH 2020
– for five years beginning in fiscal 2015.

railways,” “development of practical technologies,”and “basic research for railways.” Consequently,
it implemented 694 themes spending 13.9 billion
yen for R&D activities (Tables 1 and 2).
In order to sophisticate the simulation technology, RTRI newly established a specialty division
to be in charge of large-scale computing. For
this purpose, it introduced a new supercomputer
featuring almost 10 times faster processing
speed than its predecessor. To make R&D more

Annual Report 2014-2015

Railway Technical Research Instituteefficient, comprehensive partnership was established with the Institute of Industrial Science, theUniversity of Tokyo, while actively implementing
joint researches and contract researches withdomestic and foreign universities and other research institutes. In addition, the Institute madethe best use of occasions such as R&D reviews
where RTRI’s researchers could receive advice

and undergo assessments from outside personsof learning and experiences who were chosen as
research advisors for RTRI.
Major results of R&D were disclosed to the
public through periodical publication, technicalforums, lectures etc., and results of completed
projects were made public in the form of brochures.

Table 1: The Number of Projects Implemented in Each Fiscal Year
(unit: a number of projects)
Category

FY 2010

FY 2011

FY 2012FY 2013

FY 2014

FY2010 – FY2014

R&D for the
future of railways

34

44

62

45

37

79

Developmentof practicaltechnologies

140

134

109

111

108

310

Basic researches
for railways

124

123

111

115

135

305

Total

298

301

282

271

280

694

Table 2: R&D Expenses (before-tax prices in 100 million yen)
Category

FY 2010

FY 2011

FY 2012FY 2013

FY 2014

Total

R&D for the
future of railways

5

7

10

10

9

43

Development ofpractical technologies

12

10

6

7

8

45

Basic researches forrailways

10

10

8

9

11

50

Total

29

28

25

27

29

139

Note: Due to fraction processing, totals may not equal the sum of individual figures.
Expenses of separately commissioned projects are excluded.

Annual Report 2014-2015

57

Report on Key Activities under the Previous Master Plan RESEARCH 2010
(1) R&D for the future of railways

RTRI positioned as targets of R&D for the future of railways (1) technology development items
that would have a large spillover effect when
they are put into practical use, (2) elucidation ofphenomena that would promise a drastic breakthrough in R&D, and (3) items for basic researchsuch as building of tools. And then, the Institutedecided five major items and 12 individual items
that constituted the major ones, and eventually
total 79 themes were implemented.

1) Improvement of safety and reliability ofrailway system(Improvement of safety and reliability by intelligent
train)

RTRI built a prototype of an intelligent trainsystem to support drivers with reinforced sensing, communications, and information processing
functions. This system consists of (1) highprecision position detecting technology, (2) bogie
abnormality detection technology, (3) route information (such as conditions of ground facilities)
transmitting/receiving and storing technology, and(4) driver support technology that can provide information needed for safe operation, etc. For the
position detecting function, new equipment wasdeveloped by introducing a tachometer generator,
an acceleration sensor, etc. as components so
as to detect positions within an error of several
meters. In terms of the bogie abnormality detection, newly developed equipment could, by itself,
judge abnormalities of bogies, such as hunting
motion and a bearing loss, based on vibration andtemperature and determine a degree of danger,
and then transmit the information to an on-board
system. In addition, the Institute developed asleepiness degree detector that focused on theface of a driver through a camera as well as aforward monitoring device. Furthermore, byintegrating these devices and pieces of equipment, the Institute prototyped a system that could
decide a safe speed and a stop position, display
information in a manner that could prevent confusion of a driver, and perform drive intervention in
the event of an emergency.

58(Safety improvement against derailment andcollision)

RTRI developed a bogie whose wheel loaddecrease is controlled by adopting movablestructure for the bogie frame so that wheels could
follow track irregularity. By integrating an assist
steering system, the derailment quotient could
be reduced by up to 50% in comparison withconventional bogies in a running test conductedin RTRI’s premises. In addition, taking into account the passenger injury severity, the Instituteinvented a simulation technique of reproducing
vehicle conditions at the time of an accident,
which should be used as an evaluation methodof vehicle crashworthiness, by using a detailed
analysis model of human bodies and car bodies,including their interior materials. Simultaneously,
the Institute proposed a limit value of the integral
calculation of vehicle impact acceleration to be
used as an index for prevention of passengers’
serious injuries.

(Safety improvement against weather disasters)

RTRI developed a hazard mapping technology
to display on the Geographic Information System(GIS) such risks along railway lines as landslidedisasters, strong wind disasters, and avalanchehazards and rockslide disasters. This technology was realized by developing a local weather
numeric simulation method that could reproduce
climatic phenomena around railway lines in a
spatial resolution of 250 m and by constructing
an evaluation technique of slope failure during
rainfall time that could almost perfectly reproduce
a state of collapse in a real disaster and then by
integrating the method and the technique with amethod of evaluating a risk of a rockslide disaster.

(Safety improvement against earthquakes)

Targeting at large-scale earthquakes, RTRI
built a method of predicting main-shock andaftershock motions of magnitude 8 or stronger
earthquakes. Compared with conventional methods, this method realized a significant increase inprediction accuracy; for example, when applied to
the Great East Japan Earthquake, it could predict
instrumental seismic intensity almost within a level
range of ±1. In addition, the Institute enhanced
accuracy of the simulation method of reproducing

Annual Report 2014-2015

Railway Technical Research Institutemotions of vehicles and overhead contact line
poles observed during an earthquake. RTRI also
built a method of evaluating remaining bearing
force of structures observed after receiving large
external force, and proposed new viaduct structure that could reduce earthquake response byconnecting and integrating the foundations under
the ground.

2) Enhanced energy efficiency(Energy consumption reduction of vehicles)

RTRI developed an induction motor whose
power loss was reduced by up to 30% as a resultof change in material and structure of the rotor,
and it also made clear the effect of changing
shapes and layouts of the rooftop and underfloor
equipment in reducing air resistance. By these
efforts, energy consumption could be reduced by
10% or so. In addition, the Institute developed
an algorithm to find out a pattern of coasting andbraking which minimizes the energy consumption, and it also developed a simulator that could produce a running curve based on the algorithm. In
the test runs following the running curve producedby the simulator, the energy saving effect reached
up to 4%.

(New power supply system)

RTRI proposed a new power supply system
where renewable energy-based generating
equipment and a power storage facility are
combined and a method to control the system,
and it built a system to stabilize power supply
by coordinating fluctuations in generated power
and power consumption by electric rolling stock
operation. As a technology to efficiently provide
power, RTRI succeeded in using superconductive feeding cables laid 300 meters in RTRI’s
premises to make vehicles run. In addition, inorder to stabilize the power supply by reducing
regeneration cancellation, RTRI manufactured a
flywheel equipped with a superconductive magnet
bearing which has an electric storage capacity of
100 kWh. Furthermore, the Institute developed
an operation power simulator that could predict aninfluence of power supply from various sources
and train operation on power consumption within
an error of about 2%.

Annual Report 2014-2015

3) Maintenance innovation(New condition-based maintenance technology)

RTRI produced a prototype to detect abnormal states of ground facilities by continuously
monitoring state changes in the long and medium
terms. A monitoring system of bridge conditions
uses information from acceleration sensors anddisplacement sensors to monitor state changesof bridge columns, foundation, and beams. The
Institute made test installation and operation ofa system equipped with functions to efficiently
collect the data from the sensors by radio. Other
systems RTRI developed are a system to monitor
track irregularity using an inclination angle sensor; a system to monitor turnout-rail wear throughimages taken by a stereo camera mounted on
a vehicle bogie; a system to monitor and detect
abnormal conditions of overhead contact wire bymeasuring contact force of pantographs, etc.

(Innovation of structure renovation technology)

RTRI developed a repair/reinforcement methodof viaduct intermediate slabs whose implementation costs could be reduced by about 20% fromcosts of conventional construction methods, abeam reinforcement method, an interval expansion method between pillars to expand the space
under a viaduct, and so on. The Institute also
developed, as a construction technique to expand the space of an underground train station,a new connection method applied to new andold subway structures that could reduce costsby almost 10% from conventional methods and,as a technology to improve safety and amenity
in the space of elevated stations, an engineering
method to adopt a light membrane roof for anelevated station platform.

4) Maintaining and developing railway
networks(Evaluation and measures for internal amenity)

RTRI proposed a ride-comfort evaluation
method that matched bodily sensation of passengers, where longitudinal, lateral and verticalvibrations were simultaneously taken into account.
It also developed a variable-attenuation verticaldamper and a horizontal vibration control device
together with a method of reducing vibration toa level where riding comfort could be secured

59

Report on Key Activities under the Previous Master Plan RESEARCH 2010
through simultaneous control of two or moremodes of vibration. Moreover, a vehicle bodytilting mechanism with the maximum tilt angle of 5
degrees was developed for a pendulum vehicle toincrease vibration ride comfort and reduce travel
sickness. RTRI proposed an index for evaluation of internal noise, taking into consideration adegree of discomfort of passengers against noise.
The Institute also proposed divided floor plates
and application of microporous panels to ceilingboards as a technique to reduce internal noise.

(Evaluation of the environment along railway lines
and measures for high-speed operation)

RTRI created a technique to estimate strengthof aerodynamic sound generated from bogies
by conducting a wind-tunnel test using an approximately 1/7-scale model vehicle. With thistechnique, it became possible to separately
estimate the aerodynamic noise from the lower
part of vehicles and the rolling noise. As a result,with this technique, the degree of contribution
by each noise source can be estimated and thedata can be used to estimate the effects of noise
reduction measures. RTRI developed the windload reduction type of noise insulation device
that could be opened under the strong wind to
reduce loads on existent structures; moreover, theInstitute developed a sound insulating-material
for rail joints. It also built a simulation method
to predict vibrations of the ground and buildings
along railway lines by taking into consideration
the impacts of passing vehicles.

(Transition facilitation at junctions)

RTRI proposed a method to quantitatively assess convenience provided by routes for transfer
between buses and trains, and it also developed
a simulation method to predict a passenger flow
though inner-city traffic, including abnormal situations such as transport disorder, while identifying
bottleneck stations in intercity traffic and trains
expected to be converged on by passengers.
Furthermore, the Institute developed a simulator to recapture running of trains using the train
performance curve it worked out for this purpose,and then produced a system to evaluate operation plans from a viewpoint of improvement of
convenience for passengers and energy-saving

60

effect.

5) Building a railway simulator(Design and development of the railway simulator
core system)

RTRI built a prototype of a virtual railway test
track to analyze dynamic mutual interaction
among structures, tracks, and vehicles and thatbetween overhead contact wire and pantographs,
where a trainset was running. It was confirmedthat the vehicle acceleration obtained by the simulation with a trainset model had an error of 1% orless to the acceleration of a real train’s runningon the RTRI’s test track. It was also confirmed
in a large-scale structure/wheel interaction modelthat the stress at the wheel/rail contact point had
an error of 10% or less to that obtained from atheoretical formula. In the model of conditions
between overhead contact wire and pantographs,
it was confirmed that the vertical movement of apantograph had an error of 10% or less to measured values.
In addition, RTRI developed a seismic hazard
simulator to predict earthquake motion propagation from the epicenter to a given point along arailway track and seismic damage to structures
which may be generated there. It also developed
another simulator to predict aerodynamic noise
and the airflow around a pantograph throughlarge-scale calculation based on an orthogonal
grid method. It was confirmed that the seismic
hazard simulator presented the seismic intensity
on the ground level that had 10% or less errors
to values observed during the Great Hanshin
Earthquake; and the prediction simulator of the
airflow around a pantograph showed that its error
to the wind-tunnel experiment data could become
10% or less by increasing the number of grids.

(2) Development of practical technologies

RTRI responded timely and appropriately tovarious requirements from JR companies andimplemented total 310 themes, including the
research topics of RTRI’s researchers’ own
choice that met needs of railway operators and,at the same time, had higher priority in RTRI’s
R&D, in addition to designated topics that could
contribute to solution of problems in the actual
railway operation.

Annual Report 2014-2015

Railway Technical Research Institute1) Improvement of safety

IIn the “development of an earthquake early
warning system using sophisticated alarm algorithm,” RTRI created an algorithm that could
enhance prediction precision of earthquake
factors using the P wave and then developed aprototype seismometer in which the algorithm wasused. Currently, a verification test is going on,
aiming at the mass production. And, it also proposed a new method of sending alerts based ondata collected from ocean-bottom seismographs.
In the “development of a method to reinforce
masonry walls combining landslide prevention
netting and rock mass reinforcement materials,”
RTRI proposed a seismic strengthening method
in order to prevent collapse of masonry walls
during an earthquake. This method combinesprotective netting which is easy to install andground reinforcement materials. In addition, RTRI
worked out a related design manual.
In the “development of an interview techniqueto analyze the background factors of an accident,”
RTRI developed an interview technique to be
used by accident investigators of train operationcompanies as well as an educational program toteach the technique; consequently it was confirmed that it was effective in helping the survey
respondents express their views more actively on
the situations and background of errors.

2) Harmony with the environment

In the “development of a reducing method of
micro-pressure wave,” RTRI invented a hood withinside partition to be installed at the tunnel exits
in order to reduce micro-pressure wave generated by Shinkansen trains running at ever higher
speeds. Its effect has been confirmed by modelexperiments. This type of a hood can be installed
at locations where a longer tunnel entrance hoodcannot be installed.

3) Cost reduction

In the “development of an integral bridge using
reinforced soil,” RTRI developed a new structure
form characterized by higher seismic resistanceat the joint area connecting a bridge and embankment, a weak point in the structure, This type ofstructure was realized by integrating reinforced
embankment and a bridge. After confirmation

Annual Report 2014-2015

of sufficient strength using a test bridge, it wasapplied to real bridges.

4) Improvement of convenience

In the “practical application of the new silicon
buffer for freight train,” RTRI developed a buffer
featured by excellent shock absorbing performance and durability in order to prevent collapseof cargo on container wagons caused by theirlongitudinal motion. It was confirmed in runningtests that this buffer could reduce longitudinal
vibration motion of a running train. Accordingly, averification test of durability has started with commercial vehicles, aiming at practical application.

(3) Basic researches for railways

In the field of basic research which is to be thestarting point and foundation of practical technologies RTRI has put higher priority on the four items,
that is, (1) sophistication of the simulation technology, (2) analysis of degradation and deterioration,(3) enhancement of evaluation technology, and(4) human factors. Including research on theMaglev, magnetically levitated train technology
and its application to conventional railways, theInstitute implemented total 305 projects.

1) Improvement of safety

In the “elucidation of rainfall resistance ofearth structure after an earthquake,” RTRI built
an analysis method to evaluate the influenceof rain water which flows into cracks generated
by earthquake motions and conducted a modelexperiment and a validation analysis using a realembankment, which elucidated the mechanism ofafter-quake decrease in the embankment rainfall
resistance. In this study, the amount of decrease
was also quantitatively measured.
In the “ analysis of large-scale soil deformation
using particle method,” RTRI built a simulation
method for modeling soil and water in the formof particles, evaluating complicated deformation
behavior of the ground and groundwater, and finally reproducing large-scale ground deformation
phenomena such as a slope failure, soil liquidation and debris flow.
In the “efficient learning method for fingerpointing and call,” RTRI produced a software for
personal computers to learn that finger-pointing

61

Report on Key Activities under the Previous Master Plan RESEARCH 2010
and call are effective in preventing human errors.
Using this software, RTRI designed a learning
method which enables drivers to actually feel its
effects. As a result, about 700 drivers admitted
its effects in human error prevention and safety
training.

2) Harmony with the environment

In the “waveform predicting method of micropressure wave,” RTRI improved a simulation
method of predicting a compression wave thatwas formed when a train rushed into a tunnel andthus enhanced prediction accuracy of a micropressure wave emitted from the other mouth ofa tunnel. As a result, the calculation errors to theresults of field tests were reduced approximately
to one-third.
In the “improvement of evaluation technologyof the inductive interference analysis,” RTRI
proposed a technique to predict electromagnetic
noise generated from underfloor devices of vehicles by calculating noise levels of electric current
flowing through traction motor wires with reference
to vehicle specifications. With this technique, it
became possible to predict electromagnetic noisefrom underfloor devices of vehicles at the stagesof designing and manufacturing. Previously suchnoise had been measured only on completed
vehicles.

2.1.2 Investigation

RTRI conducted investigations to search new
R&D challenges toward the future, and eventually
selected issues such as sophistication of railway
disaster-mitigation technology, etc. The Institutealso set up a dedicated group in charge of strategic
investigation in fiscal 2011, promoting investigations to comprehend mid- and long-term social
and technological trends with a focus on specificfields related to railways such as safety, environment, and traffic economy. Some of investigation
results were later adopted as R&D themes. And
these results were publicized through the RTRI
Technical Forum and its journal RTRI Report .

2.1.3 Technical Standard Services

RTRI worked out three categories of drafts
including seismic-resistant design standards andtunnel design standards, while implementing nine
survey and research items such as evaluationsof car body rolling displacement and a magnetic
field in a vehicle. In addition, RTRI prepared 25
design support tools, including design calculation
examples related to technical standards.

2.1.4 Information Service3) Cost reduction

In the “functional improvement of pantographs
by use of control technology,” RTRI proposed an
active control technology of Shinkansen train
pantographs in order to enhance current collection performance without extensively upgrading
overhead contact wire equipment. Meanwhile, it
was confirmed that this technology could reduce
fluctuation in contact force with overhead contact
wire by almost 70%.

Technical information regarding railwaya
was actively collected and stored from various domestic and overseas sources, including
documents, magazines, standards, and othermaterials. Meanwhile, RTRI’s R&D activities andthe results were made open to the public throughperiodicals and its websites. RTRI continued its
efforts to digitize its collections and the results of
its research and development so as to improvethe collections of its electronic library.

4) Improvement of convenience

2.1.5 Publishing and Training

In the “study of practical application of linear rail
brake,” RTRI designed and made a prototype of alinear motor type of eddy-current brake system forhigh-speed vehicles that could be operated using
self-generated power even during power outage
and could provide braking force without contact
with rails. Subsequently, the Institute mounted

62

this prototype on a test vehicle to successfully
confirm that it could provide braking force as
designed.

RTRI has been issuing periodicals “RTRI
Report,” “RRR,” “Quarterly Reports of RTRI
(QR),” and “Information on World-Wide Railway
Technologies (WRT).” Contents of RRR underwent renovation to be further enriched. Moreover,
RTRI held RTRI Lectures for timely themes suchas “Towards Further Improvement of Railways,”

Annual Report 2014-2015

Railway Technical Research InstituteMonthly Presentations to publicize the research
results, and Railway Technical Seminars to provide
training courses and disseminate technologies.
RTRI also organized the RTRI Technology Forumat the Kunitachi Institute and in Osaka to publicize
results and contents of R&D activities directly toparties concerned with railways.

2.1.6 Diagnosis and Consulting

RTRI handled 2,147 cases of consulting

services, meeting the requests by railway operators and other parties concerned (Table 3).
Among them, 250 cases were related to cause
investigations into accidents, vehicle troubles,and ground facility malfunctions, proposals ofcountermeasures, and support for post-disasterrecovery. And other 1,897 cases were concernedwith technical guidance (including lending ofequipment and sending RTRI’s experts) to solve
problems related to railway technology.

Table 3: Consulting Case Numbers
Category
Consulting(Equipment failures,
disasters, etc.)

FY 2010380(58)

FY 2011390(42)

2.1.7 International Standard Services

RTRI tackled activities related to international railway standards in a strategicmanner. Responding to Japan’s proposals, theInternational Electrotechnical Commission (IEC)
issued international standards of the on-board
primary linear induction motor, the condenser for
power electronics, and the transmission system
in a trainset based on Ethernet and publishedtechnical specifications of the wireless train control system. The Commission also discussed
an on-board electric power storage system andother two technical matters. The International
Organization for Standardization (ISO) issued
the international standards of materials of synthetic sleepers, as Japan proposed, and actively
discussed railway project plans and vehicle air
conditioning systems.

2.1.8 Qualifications

RTRI held the accreditation test for Professional
Railway Design Engineers in Tokyo and Osaka.
The number of examinees was 3,750 in total
and that of successful applicants was 674.
The Institute also renewed its status as a testing agency authorized by the Minister of Land,
Infrastructure, Transport and Tourism, extending
the expiry date of the status for five more years.
In addition, in fiscal 2012, it extended the valid
term of the first stage examination certificate from

Annual Report 2014-2015

FY 2012443(53)

FY 2013482(46)(unit: a number of cases)
FY 2014
452
(51)

Total
2,147
(250)

one year to three years for the convenience of
examinees.

2.1.9 Railway Technology Promotion
Center

RTRI communicated closely with railway andtramway operators and regional railway associations to grasp common technical needs, while
promoting R&D, diagnosis and consulting, information services, and other types of business inaddition to technical standards services.
In the business field of R&D, RTRI took on
17 research and study projects and alreadycompleted 11, including “the study of measuresagainst lightning damage on signal equipment.” Indiagnosis and consulting, the Institute responded
to 406 inquiry cases regarding technical issues
in its effort to support local railway operators,
while providing onsite advice in 11 cases andconducting onsite investigations in 48 cases. In
information services, RTRI’s Database System
on Railway Accidents was additionally equippedwith a function of railway accident search bycause in fiscal 2014. RTRI also issued a new
training material for mid-level engineers, that is,
the fifth edition of “Railway Technology to Learn
from Accidents.” It also held lectures on themes
such as energy conservation in two to four venues
every year, and also delivered lectures total 38

63

Report on Key Activities under the Previous Master Plan RESEARCH 2010
times at technical committees of regional railway
associations and on other occasions.

2.1.10 Railway International Standards
Center

RTRI set up the Railway International Standards
Center in April 2010 to concentrate its deliberationsof international railway standards on the Center,and simultaneously deployed strategic activities
to introduce Japanese technical specifications
and design concepts into international standards.
The Institute secured a leading position in ISO/TC 269 (Railway Applications), set up in April
2012, because the Institute had been involved inmanagement of the Technical Committee from anearly stage and one of its staff assumed the officeof chairman of the Committee. Furthermore, RTRI
promoted information sharing with European andAsian standards organizations, and contributed tohuman resources development in Japan throughorganizing seminars.

2.1.11 International Activities

RTRI continued joint research with SNCF (French National Railways), RSSB (the Railway
Safety and Standards Board) of the UK, CARS
(China Academy of Railway Sciences) andKRRI (Korea Railroad Research Institute), andstarted new joint studies with DB SystemtechnikGmbH (DBST), the French Institute of Scienceand Technology for Transport, Development
and Networks (IFSTTAR), the Politecnico deMilano, etc. The Institute implemented total
47 joint research projects with universities andresearch organizations in Europe and Asia, andsent 20 researchers to these organizations
on a long-term basis (Table 4). It also held the10th International Workshop on Railway Noise(IWRN10) in Nagahama and another international
workshops on study ballasted-track maintenanceand wheel/rail damage.
RTRI participated in various international
conferences for presentations and informationexchange. RTRI has been a member of theorganizing committee of the World Congress
on Railway Research (WCRR) over years andsupported the management of WCRR2011,
WCRR2013, and WCRR2016. Moreover, as partof its international activities, it organized research

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forums and technical seminars in order to expand
technology exchanges with Asian countries. RTRI
also gathered and shared information on current
states of railways and high-speed railway projects
in each country .

2.1.12 Tohoku-Pacific Ocean Earthquake
Countermeasures

In the wake of the Great East Japan Earthquakethat occurred in March 2011, RTRI made fieldobservations and provided technical guidance
for recovery in response to requests of railway
operators. The Institute joined a subcommitteeof the Investigation and Examination Committee
created by East Japan Railway Company toanalyze behaviors of vehicles and electrification
poles at the time of the Earthquake, and becamea member of some advisory councils set up by
the Ministry of Land, Infrastructure, Transport
and Tourism. As RTRI’s support for recovery/
reconstruction works of railways from damage
by the Earthquake, the “Technical Proposals for
Recovery/Reconstruction of Railways” was compiled to offer immediately applicable technologies
that were mainly developed by RTRI .

2.2Profit-making business

Railway operators, independent administrative
agencies, and other parties placed orders to RTRI
for a contract research concerning installation ofan urgent earthquake detection system, surveys
and researches of construction of new Shinkansen
lines, R&D for gauge change trains, and so on,
resulting in total 2,706 business contracts that
produced an income of 14.8 billion yen.
To promote business, vigorous quality control
procedures such as a customer satisfaction survey were implemented, and sales activities wereintensified , for example, by holding a technology
exchange conference. Other efforts were also
made to make business activities more efficientand enhance staff’s awareness of income andexpenditure management.

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Railway Technical Research Institute

2.3Commissioned R&D projects

The Government entrusted RTRI with investigative research of technical standards while
independent administrative agencies placedsome tasks such as a slope stability assessment
in RTRI’s charge, resulting in total 35 R&D casesthat produced an income of 1.24 billion yen. The
total revenue was 16.1 billion yen, covering profitmaking business and R&D projects entrusted by
the Government.

Table 4: Participant Universities and Institutes in Joint Researches
Name

University

Railway operator/Institute

CARS (China Academy ofRailway Sciences)
KRRI (Korea Railroad
Research Institute)
SNCF(Société Nationale desChemins de fer Français)RSSB(Railway Safety and Standard
Board)Country
China
Republic of
Korea
FranceUK

Theme

Starting
Year(Japan-China-ROK joint study)
Standardization of electromagnetic
compatibility (EMC) and other 14 themes

1992(Japan-France joint research)
Energy saving system and other 13
themes(Japan-UK joint research)
Recurrent checks on railway sites andother three themes

1995

2008

SBB
(Swiss Federal Railways)

Switzerland

Optimization of transport planning andoperating method

2011

DBST
(DB Systemtechnik GmbH)Germany

Micro-pressure waves

2014

IFSTTAR(French Institute of Scienceand Technology for Transport,
Development and Networks)

FranceReinforced soil technique

2014

Chalmers University ofTechnology

SwedenRolling contact fatigue and other twothemes2010

Massachusetts Institute ofTechnology

US

Magnetic-field property of high Tc
superconductive equipment and othertwo themes

2010

University of Bristol

UK

High-precision thrust control with anumber of actuators

2012

Cambridge University

UK

Adaptation of a monitoring technique forcivil structures

2012

Columbia University

US

Seismic design of earth structures

2013

Newcastle University

UK

Passenger injury evaluation at the timeof a train collision

2014

Politecnico di Milano

Italy

Dynamic interaction between vehicles
and track structures on a long-span
railway bridge

2014

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65

Report on Key Activities under the Previous Master Plan RESEARCH 2010

3

Management

3.1

Compliance, etc.

RTRI established the Compliance Promotion
Office in July 2010 where rules and procedures
were formulated and the reporting contact officeand the consultation window were set up. The
Institute strengthened its compliance system andimproved research ethics by conducting staff
training, preparing handbooks, disseminatingcompliance information, and encouraging staff
to do self-learning through an RTRI version ofe-learning system.
To reinforce the information management system, RTRI reviewed its management method andinformation handling, which resulted in abolition ofcurrent rules and establishment of new information management rules that were announced to
all the RTRI staff members for strict observance.
To make RTRI’s office and facilities safer andmore convenient for work, the Institute took necessary measures to enhance staff’s awareness ofsafety issues and streamline work environment.

Resources and3.2Human
Personnel

RTRI was engaged in its business with thenumber of its personnel kept around 530 every
fiscal year as per the Master Plan (Table 5).
Specifically, RTRI added to its payroll 86 newstaff members to prevent a fault in technology
succession, employed 11 experienced workers as

mid-career hiring, and rehired 47 old and retired
staff for technology succession. In response to theamendment of the Law Concerning Stabilizationof Employment of Older Persons, the Institutereformed its system so as to make those whowanted to continue work in RTRI after age-limit
retirement eligible for continued employment. In
addition, working patterns in RTRI became more
multifaceted, where work-life balance was taken
into consideration, with introduction of a shorttime working scheme and expansion of child-careleave.
At the start of fiscal 2012, those employed
after the launch of JR accounted for more than
80% of all the RTRI staff, so that a focus was set
on the inheritance of technologies with introduction of OJT practices to address the generation
change. As a new initiative, RTRI systematized
its education program by renovating contents ofstratified education training. In order to develop
researchers who are experienced in actual train
operation and capable of doing research which
directly meets rail operators’ needs, RTRI has
provided various training opportunities to its employees in and out of the institute and promoted
personnel-exchanges with JR companies.

3.3Organizations

The Railway International Standards Centerand the Compliance Promotion Office were set
up in fiscal 2010.

Table 5:PNumber of employees
FY 2010

FY 2011(unit:person)

FY 2012FY 2013

FY 2014

Actual number

530

540

540

534

534

Plan

530

530

530

530

530

Note: Each figure in the upper row shows an actual number at the start of each fiscal year.

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Railway Technical Research Institute
In addition, the Signaling & Transport
Information Technology Division was founded infiscal 2012 to intensify and streamline the R&D
system aiming at active use of ICT. The Center
for Railway Earthquake Engineering Research
was founded in fiscal 2014 as a base to concentrate and conduct earthquake-related research
activities, provide technical guidance and personnel training concerning earthquake-resistantmeasures, and deliver restoration support at thetime of earthquake, in order to raise the speed
and efficiency in the research into earthquake
issues.
Moreover, a new research laboratory,
Computational Mechanics, was set up in the
Railway Dynamics Division in fiscal 2012 in orderto focus on developing, maintaining, and enhancing advanced simulation technology,

3.4Facilities

As for test facilities, RTRI’s rolling stock test
facilities were renovated to conduct vehicle tests
more stably and hunting motion tests at highspeeds more safely. Further introduction andimprovement of RTRI’s unique facilities were carried out, including the axle fatigue test machine
to study in a real-size setup a process of cracks

4

generated on an axle progressing and resulting
in a break; the structure loading test equipment toimplement loading experiments of civil structures
where experimentation was linked to a numericanalysis; and the load and rolling test equipment
to assess performance of the car-body tilting
system and a control method of it.
Concerning general facilities, RTRI applied
safety measures and aseismic reinforcement
work to experiment facilities, while installing
solar power generation devices as a global environmental measure and renovating obsolete
equipment.

3.5

Balance of Payments

On the income side, the income for sharedservices was total 65.8 billion yen, exceeding aplanned value by 3.6 billion yen. The amountof total cash subsidies, including a government
grant, was 3.6 billion yen.
As for expenditure, RTRI spent total 1.48 billion
yen for R&D, an increase by 3 billion yen over aplanned value due to increase in money grants.
Payments for purchase of fixed assets were 3
billion yen, 500 million yen over a plan due torenovation of the rolling stock test equipment andso on.

Vision of RTRI and Next Term’s Master Plan

RTRI formulated a new vision, “RISING – Wewill develop innovative technologies to enhance
the rail mode so that railways can contribute to
the creation of a happier society.,” which orients
RTRI’s aspiration and future advancement, inorder to respond without delay to the changing
society and diversifying needs, create high-quality
results, and thereby meet expectations of therailroad industry and society.

Annual Report 2014-2015

In fiscal 2015 a new five-year master plan
“RESEARCH 2020 -Aiming at creation of innovative technologies” was launched.

67

YEAR 2014-2015: April 1, 2014 - March 31, 2015
Copyright© 2015 Railway Technical Research Institute.
All rights reserved.
Published by Fuminao OKUMURA, Executive Director
International Division, Railway Technical Research Institute
Hikari-cho 2-8-38, Kokubunji-shi, Tokyo 185-8540 JAPANFind us :WEB: http://www.rtri.or.jp/eng/index.html
Facebook: https://www.facebook.com/rtri.eng

For download :Brochure & Annual Report: http://www.rtri.or.jp/eng/rtri/brochure.html
Railway Technology Newsletter:http://www.rtri.or.jp/eng/publish/newsletter/index.html

68Annual Report 2014-2015