ANNUALREPORT2017-2018
For the year ended March 31, 2018

Railway Technical Research InstituteForeword
Norimichi KUMAGAI
President of the Railway Technical Research Institute
After celebrating its 30th anniversary in 2016,
RTRI took one step forward in 2017. In the past 30
years, we have been exploring how to contributeto railway operation and businesses with ourtechnical development and which technical fields
we need to address and doing research in that
direction. Being supported by the national government and rail-related companies, our researchers
have been creating quality research outcomes
and working to establish credibility.
In 2015, RTRI announced a new vision“RISING – We will develop innovative technologies to enhance the rail mode so that railways cancontribute to the creation of a happier society,” inorder to meet the expectations from the railway
world and Japanese society. As a mid-term plan tostate concrete strategies to implement the vision,
we publicized a five-year master plan starting in
2015, “RESEARCH 2020 - Aiming at Creation of
Innovative Technologies -“RTRI has been seeking to use informationand communication technology extensively inresearch and development. In June 2017, the ICT
Innovation Project was started at RTRI to address
the goals of “reducing natural disaster damage,”“low-cost maintenance” and “energy saving.” Themost important challenge for the next 30 years is
to combine IoT, big data analysis and simulation
by supercomputers and to integrate it with AI. In
this process, it will be important to keep in mind
man-machine role sharing.
In order to keep providing quality researchoutcomes to enhance railway values and to berelied upon by railway users, continued support
and advice from all the rail-related people will bemost appreciated.

In fiscal 2017, the third year of the master plan,
we focused on the research and development toenhance railways safety. We implemented projects to make railways more resilient when serious
natural disasters such as major earthquakes andheavy rain and snow falls occurs, and projects toprevent derailment, accidents at level crossingsand human errors. We have also promoted research and development to enhance convenienceof train travels, to reduce maintenance cost andto build energy-saving railway systems as wellas the research to raise Shinkansen’s speed andto further enhance simulation technologies. For
the purpose of increasing Shinkansen’s speed,
the high-speed pantograph testing machine andlow-noise train model testing machine have been
built.
Annual Report 2017-20181

Overview

Contents

Organization

2 Overview
4

Major Results of
Research and Development

Board of Trustees

Board of Directors

Auditors

35 News Release
Plan
57 MasterRESEARCH 20202

Annual Report 2017-2018

Railway Technical Research InstituteExecutive
Vice
Presidents

ChairmanPlanning Division

Vehicle Structure
Technology Division

Compliance Division

Vehicle Control
Technology Division

President
Executive
Directors

Administration Division

Structures
Technology Division

Miyazaki Test
CenterPower Supply
Technology Division

Accounting Division

Track
Technology Division

Information
Management Division

Disaster Prevention
Technology Division

Health Insurance
Systems Center

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

Signalling &Transport Information
Technology Division
Materials
Technology Division
Railway Dynamics
Division
Environmental
Engineering Division
Human Science
Division
Maglev Systems
Technology Division
Yamanashi
Maglev
Test Center
Center for Railway
Earthquake Engineering
Research(As of April 1, 2018)

Annual Report 2017-2018

3

Major Results of
Research and Development
IMPROVEMENT OF SAFETY
1. Earthquake damage simulator for railways with self-correcting function• A simulator was built to be able to estimate the behavior of railway structures, electric poles andrailway vehicles during earthquakes.
• A self-correcting function for input parameters corresponding to observed ground motions and railway
damage data was added.
• A simulator makes it possible to reduce the time required to resume railway services after an earthquakeby ranking structures in order of priority for inspection.
Rapid recovery of railway operations following anearthquake depends on being able to quickly obtain data
about damage that has occurred. Until now, damage
was estimated on the basis of seismic intensity observed
through trackside seismographs and seismic damage
nomographs, using the natural period and the yield acceleration of structures as parameters. This meant thatobtaining more detailed damage estimation using local
ground and structural characteristics, was difficult. This
abstract introduces an earthquake damage simulator witha self-correcting function (Fig. 1). Simulation begins automatically when an Earthquake Early Warning is received.
The simulator processes the information available at thatmoment (epicenter, seismic observation records, etc.) andpredicts trackside seismic waveforms in real time. The
simulator can estimate damage through detailed dynamic
analyses of the behavior of structures, electric poles andrailway vehicles using the seismic waveforms.
Using the simulator, damage can be estimated within

Acceleration (gal)Real-time estimation of
trackside ground motions
1500

M7.4, Distance 25km

0
-1500
0

10

20
30
Time (sec)several minutes to several tens of minutes taking into
account the difference of in characteristics of deep soil
structures, the surface ground and vibration characteristics
of each railway structure. An algorithm automatically updates the parameters in the simulator used for estimating
damage by adding information, such as boring survey
data and structural design sheets, and observed groundmotion. As a result, damage estimation can automatically
improve with as damage and earthquake data is collected
and accumulated.
Generally, increasing simulation accuracy requires
longer calculation time. This simulator however, manages
to combine high precision and immediacy thanks to theself-correction function and ranking of structures in orderof priority for inspection, thereby allowing operations toresume more quickly following an earthquake.
This research was financially supported by the Ministryof Land, Infrastructure, Transport and Tourism.

Result of damage
 Structures
predictions
 Electric poles Railway vehicles
The damaged area

Transmission ofdamage estimation

Initial ground conditions(Amount of data is small)

The detailed dynamic
analysis of…

40
Accumulation ofsoil survey data

earthquake magnitude M○. ○Epicenter xyz

Result of theparameter update

Reception of earthquake
early warning
Feedback on real damages(automatic update of parameters)

Detection of large
amplification area

Fig. 1 Outline of earthquake damage simulator for railways

4

Annual Report 2017-2018

Railway Technical Research Institute

2. Practical application of early earthquake warning method using
ocean bottom seismometer data
• An earthquake early warning method utilizing ocean bottom seismometer data was developed, towhich observation data was applied to investigate the suitability of the specified values used in themethod and its effectiveness in preventing false alerts.
• This method is expected to be able to generate warnings 10 secs earlier than with the previous method
for subduction-zone earthquake.
An early earthquake warning system was developedthat uses ocean bottom seismometer (OBS) data frompublic agencies. After completion of OBS installation, data
could be collected and applied to previously proposed
warning methods in order to verify them in practice. Afteradding a processing method to prevent false alerts, anearly earthquake warning system for practical use on therailways was proposed.
Data for 137 earthquakes recorded in the S-net system
maintained by the National Research Institute for Earth
Science and Disaster Resilience was employed first,
to extract the attenuation relationship and amplification
characteristics for the target regions (Fig. 1). The firstobservation was that the peak ground acceleration extracted from the S-net data agreed well with the attenuation
relationships found in data collected on land, secondly,
compared to on-land data, the tendency of the amplitude
to become amplified, was confirmed.
The data showed the same tendencies as results
obtained from the small ocean bottom seismometer network used for studying the method. This demonstrates
the adaptability of the new method to an early warning

Maxmum acceleration (gal)1000

system which can consider the attenuation relationshipand ocean bottom amplification characteristics.
Following on, ordinary noise characteristics wereclarified, and it was found that preventing false alerts byprocessing data from one seismometer was a problem. In
order to reduce the risk of erroneous warnings, a multiplesite processing method was proposed, where a warningis sent out if the observed data in one site exceeds thewarning threshold level (Fig. 2, Red) and the detection
threshold level is exceeded in another site at the sametime (Fig. 2, Blue).
The new system based on multiple sites was not slower
in generating warnings, than the existing system which
sends out warnings when a fixed threshold level is exceeded in only one site, whereas it can reduce the risk oferroneous warnings being sent out.
It is expected that employing data collected from ocean
bottom seismometers in early earthquake warning systems
in addition to on-land seismic data will make it possible
to generate warnings 10 secs earlier than the previous
system which used solely on-land data.

Seismometers in the vicinity(Groups of ocean bottom
seismometers for detection)

100

10

Ocean bottom seismometerused for early warning system

K-NET (On-land site)
S-net
Attenuation relationships forpeak ground acceleration
based on land seismic data

1

0.1

1

10

100

AND

1000

Epicentral distance (km)Fig. 1 Comparison of observation data with attenuation
relationships

Annual Report 2017-2018

Ocean bottom seismometerused for detection within thesame group

Warning threshold level is exceeded

Detection thresholdlevel is exceeded

Warning

Fig. 2 Warning processing method using multiple sites

5

Major Results of Research and Development

3. Countermeasures to prevent subsidence of abutment backfill
and track buckling during earthquakes• The mechanisms of ballasted track buckling during earthquakes resulting from subsidence of abutment
backfill , were clarified.
• A countermeasure to prevent buckling was proposed, consisting of an integrated ballast retaining walland contiguous pile wall for reinforcing the abutment backfill.
The mechanisms leading to buckling of ballasted trackwith continuous welded rail due to the decrease of lateralresistance force by the subsidence of abutment backfill,
were clarified. Based on the insight gained, a countermeasure was proposed to prevent the fall in lateral resistanceforce, consisting of a contiguous pile wall to reinforce theabutment backfill, buckling prevention plates added tosleeper ends, and installation of a ballast retaining wall
fixed to the pile wall (Fig.1).
A large scale shaking table test was performed on
an integrated embankment / track model (scale of 1/9)
with heated rails to raised axial forces, to reproduce
abutment backfill subsidence and track buckling, and toinvestigate the effectiveness of the proposed anti-bucklingcountermeasure.
For tests carried out with the unreinforced abutment

backfill, significant subsidence occurred without track
buckling when a 400gal sinusoidal wave was input (Fig.
2). In the case where the embankment was reinforced witha contiguous pile wall, subsidence was reduced to about athird of the case where no contiguous pile wall was added.
However, when only the abutment backfill was reinforced(without track reinforcement) and the sinusoidal wave wasincreased to 600gal, to simulate a very large earthquake,
exceeding the force of an L2 earthquake, track buckling
occurred. When anti-buckling plates were added to eachend of each sleeper, and a ballast retaining wall fixed to thecontiguous pile wall, no buckling occurred when sinusoidal
waves of 600gal and even 700 gal were input, confirmingthat this countermeasure is effective for the prevention of
track buckling (Fig. 3).

Track without any
reinforcement or
countermeasure

Abutment

Fastening bolt

Ballastretaining wall

Embankment
Anti-bucklingplate

Contiguous
pile wallFig. 1 Integrated ballast retaining wall and contiguous pile wall

66 mm subsidenceof embankment withsinusoidal wave
400 galAbutment
BridgeAnti-buckling countermeasure(Ballast retaining wall +anti-buckling plate)Fig. 2 Subsidence of abutment backfill without
countermeasure

Anti-buckling countermeasure(Ballast retaining wall +anti-buckling plate)

Track without
reinforcement
Embankment

Buckling

40 mm subsidenceof embankment
with sinusoidal
wave of 600 gal

Buckling occurs due toembankment subsidence
and collapse of ballast,
exposing sleepers anddecreasing lateralresistance force

6 mm subsidenceof embankment
with sinusoidal
wave 600 gal

BridgeFig. 3 Track buckling on track without reinforcement (left) and with reinforcement (right) (with reinforced embankment)

6

Annual Report 2017-2018

Railway Technical Research Institute

4.Ground surface layer response evaluation method for verylarge earthquakes• A method for testing soil deformation characteristics was developed for conducting dynamic groundresponse analyses.
• A hybrid ground response testing device was developed in order to take into account ground including
unusual soil.
• The proposed method can contribute to seismic design for railway structures and assessing soilliquefaction potential.
In the case of ground containing unusual soil, such as
soil with friable particles or of volcanic origin, producing thecorrect model for analysis based on the results obtained
from the proposed method was found to be sometimes
impossible. Therefore, a hybrid ground response test
device was developed, which reproduces special soil
characteristics through shear tests on the one hand, andthose of ordinary soil through simulation (Fig. 2). Adopting
this hybrid approach has made it possible to evaluate thesurface ground response even in cases including unusual
soils.
Response analysis
using results from
The results
proposed method
from
this
0
method canModel test
Clay
contribute（≒correct）
to seismic
design, and to
5 Loosesand
improving theSandseismic safety
Response analysis
using results fromof structures.
existing method

Table 1

Clay

Loose sand Dense sand×〇：Non liquefaction

15

Bed rock×○×○：Liquefaction
×Analysis model0

Depth (m)

5

10

15

Shear test machine

020
40Ground displacement (cm)Fig. 1 Comparison of estimated response values

Control device /measurement
systemPicture ofequipment

Sand

Unusual soils
Unusualsoils

Model test（≒correct）

×

Direct evaluation
through shear test
Displacement(based on analysis)

Clay

Existing method orordinary method
Proposed method

10

Reaction force(based on experiment)？

Usual soil
Sand

Assessment ofsoil liquefaction

depth (m )Structural safety during earthquakes depends heavily on
the behavior of the surface ground. It is therefore essential
to have correctly modeled soil deformation characteristics
in order to conduct ground response analyses, to obtain
estimated response values and soil liquefaction potentialof the surface ground on construction sites.
To do this, a deformation characteristics test is carriedout to calculated soil stiffness. However, the conventional
method (existing method) for doing this places excessiveemphasis on the rise in water pressure between soil particles caused by repeated cyclic loading, generating resultsthat underestimate the stiffness of the soil. Consequently,
a proposal was made for an alternative method (proposed
method) which eliminates the influence of interstitial waterpressure to calculate soil stiffness as much as possible.
By using the results obtained with the proposed method
to conduct the ground response analysis, it was confirmedthat ground deformation estimates (Fig. 1) and soil liquefaction potentials (Table 1) corresponded with results
obtained in model tests.

Conversion tonumerical modelusing results fromproposed method

Fig. 2 Hybrid ground response test equipment and schematic overview

Annual Report 2017-20187

Major Results of Research and Development

5. Anti-seismic reinforcement method for suspended-ceilings
with small cavities at stations• An anti-seismic reinforcement method was developed for suspended ceilings with small spaces atstations, using square pipes.
• Structural tests demonstrated the strong anti-seismic reinforcement performance of this method.
• This technique could reduce costs to less than half of that for existing methods.
In stations built beneath low viaducts, the cavity between the viaduct bottom and the suspended ceiling overthe station is small. At the same time, a minimum amountof space must be kept free inside the suspended ceiling for
passing plumbing and other pipes etc. As such, installingthe usual anti-seismic braces used for reinforcement isdifficult, since they would take up this space that needs tobe kept free. Other reinforcement methods for replacing
ceiling components such as hanging bolts etc. with channel steels exist, however, these types of constructions
are complex and costly. In addition, vibration isolating
rubber elements that are usually used as a noise abatement method, weaken this type of structure’s anti-seismic
reinforcement performance (Fig. 1).
As such, a less costly, more practical seismic reinforcement method was developed, where the ceiling cavity is
not obstructed: a hanging bolt is combined with an ordinary
Viaduct,etc.
Hanging bolt

square pipe which is secured at the bottom by a nut (Fig.
1). Structural cyclic loading tests using more than thelargest design load were carried out to evaluate the antiseismic performance of this method, and demonstrated
that it had a strong anti-seismic performance (Fig. 2).
Acoustic tests were performed to evaluate the noise
attenuating packing materials and rubber edges used toclose gaps in the ceiling. Results confirmed that the noise
abatement performance of these materials was just as
effective as the previously used vibration isolating rubber
elements.
Based on these outcomes, a new anti-seismic method
for suspended ceilings with small-cavities in stations,
was proposed (Fig. 3). In addition, it was shown that the
proposed method cuts construction cost to less than half,
compared to the existing construction method employing
channel steels and vibration isolating rubber elements.

Ceiling cavity forpassing pipes
and plumbing

Hanging bolt
Vibration
Small cavity isolating
space
rubberSquare pipe
25×1.6mm

・Seismic reinforcement braces cannot be installed
・When channel steels etc., are used as ceilingcomponents, construction becomes complex and costly
・The rubber elements cannot be used, because they weaken
the anti-seismic performance

Ceilings in stations located under viaducts, etc.

Nut

Anti-seismic reinforcement method
using square pipes

Fig. 1 Seismic reinforcement problems in station ceilings, and anti-seismic reinforcement solution using square pipe

30

Horizontal load(kN)

0m

m

4
2
0

Maximum design load

Hangingbolt
Squarepipe

Noise abatement measure
Rubber edge Noise attenuating
trimming
packing material

Nut

No load decrease

-2
-4
-0.03

No load decrease-0.0150
0.015
Deformation angle(rad)Fig. 2 Results of cyclic loading tests

8

Anti-seismic reinforcementht
eig
ty h mmiv
Ca 4500.03

Ceiling finishing material

Fig. 3 Anti-seismic reinforcement method considering
noise abatement

Annual Report 2017-2018

Railway Technical Research Institute

6. Algorithm to estimate strong wind
gusts.

locations due to such as• An algorithm has been created to estimate strong wind areas due to gusts etc., based on meteorologicalradars.
• The algorithm can predict strong wind areas due to gusts up to 10 minutes ahead, at 5 minute intervals.
Gusts such as downbursts, gust fronts and tornados
can affect zones covering several hundred meters to several kilometers in area. The anemometers used for train
operation control however are spaced at 20 km intervals,
on average, which means there is a possibility that they
will not accurately detect these gusts. Consequently, analgorithm was created to predict locations likely to beaffected by strong wind at ground level on the basis ofwind and rain-cloud conditions in the upper air, from datacollected from meteorological radars and the results ofnumerical calculations.
The first step in the algorithm detects areas (gust areain the upper air) of divergence, convergence, and strong
vorticities formed by air streams that appear noticeably,by using the wind speed difference between two adjoining
points obtained from wind velocity information observedby meteorological radars (XRAIN). After detecting theirarea, direction and speed of gust areas in the upper air, anestimation is made of strong wind locations at ground level
due to these gusts. The relational expression between thewind speeds of gust areas in the upper air and at groundlevel for each altitude was set on the basis of differencein wind speed per unit of distance at different altitudes(Fig. 2), based on the results of numerical calculations
for previous gust cases. In Figure 2, the warmer color
indicates the larger localized wind speed difference. The

Direction in which gust area is moving 0

algorithm can be used to predict strong wind areas up to
10 minutes ahead, at 5 minute intervals.
As such, this algorithm can be applied as a support tool
for safer and more prompt train operation management for
preventing natural disasters due to localized and shortterm phenomena such as gusts.
The DIAS dataset is archived and provided under theframework of the Data Integration and Analysis System(DIAS) funded by Ministry of Education, Culture, Sports,
Science and Technology (MEXT).

5km
N

Position five minutes
previously

37.8N

m
00
e6
d
u
it
Alt

N

m
00
e3
d
itu
Alt

N

37.75NN

Predicted position Predicted positionin ten minutes
in five minutes

el
lev
d
n
ou
Gr

Coastline

Detection of gust area

138.7E0138.8E510138.9E

15

Wind speed difference between two points

20

[m/s]

Fig. 1 Detection of gust area in the upper air from meteorological radar readings

Annual Report 2017-2018

Difference in wind speed
per unit of distance(m/s)/ m
0m
0
0.01
9
de
il tu
t
A

0

Fig. 2 Example of wind speed difference between two
points about 1 km apart at each altitude whilst gusts
are blowing

9Major Results of Research and Development

7. Flowchart to determine possibility of reusing bridge following
scouring damage• A decision-making flowchart was proposed for determining if a bridge can be reused after scouring
damage.
• This method shortens traffic downtime and contributes to improving the resilience of the railways.
The increase of flooding over recent years in short but
localized intense downpours and typhoons has led to more
frequent small to medium scale damage to old-design river
bridges, such as subsidence, tilting of piers or deformationof steel girder bearing seats in some cases, due to bridge
scour and subsequent weakening of the supporting ground(Fig. 1).
In order to reopen bridges as soon as possible after thistype of small to medium-scale damage, the priority is to beable to reuse the bridge by carrying out minimum repair toremaining piers and girders, rather than rebuild it. Thereare cases where the bridge’s residual resistance may staythe same even after substantial bridge scour, and so model
tests (Fig. 2) were carried out to confirm this possibility.
There are cases nevertheless, where the resistance ofthe bridge’s foundation has been severely damaged, andCollisions withdriftwood, outflow offoot protection, etc.
16% Subsidence /、tilting of bridge
pier (abutment) /exposure of piles
Outflow ofgirders / bridge due to scouring
pier (abutment)
50%
34%

START

Example of bridge piersubsidence / tilting damage

Fig. 1 Results of analysis of damage to bridge from flooding

Loadingequipment
Verticalload

the safety level at the time of construction can no longer
be guaranteed. Using the subsidence measured in thecourse of a test vehicle run as a quantitative evaluation
criterion to resume operation, a method was proposed toevaluate whether the residual resistance, estimated fromthe measured subsidence value, was well enough within
the safety margin to allow emergency repair. This wasfollowed by a proposed for a decision-making flow chart
to help determine whether a bridge can be reused or not(Fig. 3).
The present research was conducted with financial support from the Ministry of Land, Transport, Infrastructure
and Tourism.

Verification of
prerequisite conditions
Degree of damage: bridge piers / girders remain(subsidence/tilting within tolerance margin)
Residual displacement exceeds track
maintenance standard values
Nature of structure: foundation placed directly on sand/gravel groundSingle track bridge / no skewing
Deck-plate girder

Local groundsurvey plan

Preliminary
loading tests

Before scouring
After scouring
Outflow
Localized
scouring

MortarModel of bridge pier foundation(scale 1/30)

Model groundFig. 2 Scouring test on foundations of model bridge pier

10

Running tests

Survey of damage / impact test etc.
Plan for temporary girders / replacementof bearing seats
Main decision making criteria:
・Strain of steel girders
・Train running characteristics(size of compound angle)
・Residual resistance force of foundations (usability)
Main decision making criteria:
・Strain of steel girders
・Residual resistance force of foundations(safety)

Temporary restoration work based on
decision to reuse bridge(Operation resumption through slow
running speed + monitoring)
Fig. 3 Outline of flowchart supporting decision to reuse or
not reuse bridge

Annual Report 2017-2018

Railway Technical Research Institute

8. Increase in accuracy of bogie hunting stability evaluation• It has been clarified that bogie hunting is caused by a combination of running speed and lateraldisplacement of the wheelset.
• It is now possible to accurately evaluate running stability through a test method.

Bogie being evaluatedRoller(modeling rail)

Fig. 1 Hunting tests on rolling stock test standAnnual Report 2017-2018

Lateral vibration amplitude ofaxle when hunting occurs

Area where
hunting occurs

Area where hunting
disappears

Speed at which hunting occurs
with no excitation

Speed at which
hunting disappears

Loading frame(modeling half-vehicle)(“○” in Fig.2). If the initial amplitude does exceed the peakvalue (”x” in Fig2.), then vibrations diverge and hunting
occurs, and the amplitude of the vibration increases up to
the flange contact boundary. The peak value in question
decreases monotonically as the roller speed increases
from stopping speed to the generation speed.
Conventionally, to compare running stability, excitation
conditions were fixed while bogie parameters were varied.
Based on the findings of this research, adjusting the input
excitation conditions to maintain a constant initial amplitude
would prevent variance in the critical speed evaluation
values, making comparison possible.
Progress now needs to be made to develop an analyticalmethod that will make it possible to accurately estimate thecorrelation between running speed and the initial amplitude
peak value, with the aim of building an easy-to-use runningstability evaluation method that does not require complex
fixed rotation tests.

Initial amplitude of lateral vibration of wheel

It is possible to evaluate the running stability of bogies,
or the critical speed of hunting, through rotation tests on
a roller using the rolling stock test bench at RTRI (Fig. 1).
However, there may be cases where the critical speed of
the hunting differs depending on the external trigger used
to generate the hunting (excitation conditions applied to
the roller), which causes variance in the evaluation results.
If the result of an evaluation indicates a sufficiently large
safety margin at the in-service running speed, then variance is of no great consequence, however, clarification of
the exact conditions that cause hunting, would contributeto making stability evaluations more accurate, so work wasdone to achieve this.
When the roller speed is gradually increased without any
excitation, hunting occurs when a certain speed is reached(hereinafter, ‘generation speed’). Inversely, when the roller
is gradually slowed down, hunting will eventually cease
at a given speed (hereinafter, ‘disappearance speed’).
When the roller is at the speed between the generation anddisappearance speeds, whether or not bogie hunting occurs depends on excitation conditions. Various excitation
conditions were tried and the behaviors at which hunting
actually occurs were clarified experimentally (Fig. 2).
Results revealed that the amplitude value of lateral displacement immediately after excitation ceases (hereinafter,‘initial amplitude’), has an upper limit within which vibration
disappears. Vibrations disappear after excitation stops
if the initial amplitude has not reached the peak value

Running speed

Fig. 2 Conditions generating hunting motion11

Major Results of Research and Development

9. Driver visual recognition support method using image
processing• A method has been developed for projecting images onto a monitor of outside views a driver cannot
see from the driving cab due to lines of vision obstructed by parts of the driving cab, in a way whichappears natural to the driver.
• This equipment will alleviate driver load as a visual support.
The presence of large members in the driver’s cab or in
gangways can narrow a driver’s field of vision (Fig. 1). In
order to reduce these blind spots, new image processing
technology has been employed in a method to project theexternal obstructed viewpoint onto a display, such as amonitor, so that the driver can see through the blind spot as
naturally as possible. Generally, it is not possible to install acamera on the back of the member blocking the extensionof the line of vision of the driver. Consequently, as shownin Fig. 2, a forward facing camera is used, positioned ata different angle to capture the obstructed view. A virtual
screen is inserted into the camera image to reflect the
projected view. A method was then developed that makes
it possible to project the image on the virtual screen onto

a display: the 3-D coordinates in the four corners of thevirtual screen are converted to 2-D coordinates and a projection conversion program was built and used to project
the coordinates of the four corners onto the projection
display.
A prototype set of equipment was built where the blindspot image, processed in about 10ms, was projected ontoa monitor located to the side of the driver’s seat. Thisin-situ test confirmed that the driver’s natural line of vision
could be reproduced (Fig. 3). Applying this equipment as
a visual support to the driver can eliminate blind spots thatprevent the driver from seeing some stop-position signs,
etc. which alleviates driver load.

Obstructed view(blind spot)

Fig. 1 Blind spot created by members in the driver’s cabPc ic
of orr tur
vi es e issi po
on n coan din nv
d g t ert
pr o edoj dr inec iv tte er o id ’s mlin age e

YProjected area(virtual screen)

Window

Driver’s line of vision

Projection screen(object forming blind spot)

Forward facing camera
to capture image(camera for capturing blind spot) X

Fig. 2 Method for converting view point, by projection conversion

12

MonitorFig. 3 In-cab functional verification test

Annual Report 2017-2018

Railway Technical Research Institute

10. Health monitoring of very large structures using long-range
U-Doppler• Using an invisible ray laser Doppler vibrometer, it is possible to determine the overall health of an entire
structure from a distance of 300m.
• The laser’s automatically controlled scanner allows the device to detect the points on the target surface
which can offer the highest level of measurement accuracy.
• Using simultaneous measurements made from two devices it is possible to measure the natural
frequency of a continuous viaduct remotely.
A “long-range U-Doppler” has been developed (Fig. 1)
which has made it possible to investigate changes in the
behavior of railway bridges due to failing health, and evendetect deformation in ancillary structures, without the needto access elevated positions.
The long-range U-Doppler, which is a laser Doppler
vibrometer installed on a custom-built horizontally andvertically adjustable rotating base permits long-range
remote stable measurements, has extended the conventional remote measuring distance from 30 to 300m, evenwhen the target structure does not have a reflecting plate.
The laser’s automatic scanning function allows it
to identify the points on the target structure within themeasurement zone that offer the highest reflection intensity (Fig. 2). This algorithm now makes it possible toefficiently make measurements from large distances andof structures that were difficult to measure until now, forexample, measurements that have to be made from far
away, of cables with curved surfaces or structures withdirty surfaces.

For example, measurement of the tensile force of 44
cables on a cable stayed bridge with a span of about 130m,
would require four night shifts using the conventional
method, whereas the present contactless method canachieve the same result with equal accuracy in just one
hour during the day time (Fig. 3).
In addition, an algorithm was created to enable measurement of individual vibration components of viaductswith complex 3-D vibrations, using simultaneous measurements from two Long-range U-Doppler devices.
This has made it possible to measure the natural frequency of each span on the viaduct remotely, in a single
visit from a single spot.
Starting point Search area Cableof search

Laser radiation
End pointof search

Detecting deformation incatenary masts/sound
架線柱・防音壁barriers

Deflection measurement
when train passesの変状検出

Reflection intensity
High

Measuringtensileケーブル
strengthof cables

張力測定

列車通過時のたわみ測定

Understanding
全体挙動のoverallbehavior
把握of structure

Cable

High

Determining state of
連続高架橋の
health of continuous
健全度判定
viaduct

Fig. 1 Applications for long-range U-Doppler

Automatic detect ofpoint with highest
reflection intensity

Fig. 2 Measurement cable and automatic collimation

Long-range
U Doppler

Cable tensile force（MN）

Microtremors
Admissible tensile value

5
4
3
2Conventional method

1
0

1

2

3

Contactless measurement

4 5 6 7 8
Cable number

9 10 11

Fig. 3 Example of measurement of tensile force of cables on cable stayed bridge

Annual Report 2017-2018

13

Major Results of Research and Development

11. Influence of pinion shaft bearing endplay (axial clearance)
on its seizure initiation• The change in pinion bearing endplay due to the temperature variations of the pinion and its peripheral
parts was clarified.
• Assembly methods capable of not reducing the endplay to near 0 mm during the shaft rotation, andstructures capable of eliminating the adjustment of the endplay, were found to be effective in preventing
pinion bearing seizure.

Maximum rotational speed : 3000 rpm

0.14
0.12
0.10

Endplay at assembling (25℃)

0.08
0.06

Gear oil Measured Calculated
temperature value
value
10℃
30℃
50℃

0.04
0.02
0.00

0

10
20
30
40
50
Time from start of rotation(min)60

Fig. 2 Variation in end play after rotation begins

Fixed outer ringer
Roll
Inner ring
Pinion shaft
Endplay: movement of pinion shaft in
the horizontal direction depending on
internal clearance of pinion bearings

0.06
0.04

Bearing
PinionFig.1 Pinion shaft bearing endplay

End play at assembling (25℃)

0.02

90

0.00

Torque(Nm)Rotation

0.08

Bearing temperature(25℃)

Outer ring

14

0.16

Endplay (calculated value)(mm)Fixed outer ring

From these results, it can be concluded that assembly
methods capable of not reducing the endplay to near 0mm during the shaft rotation, and structures capable ofeliminating the adjustment of the endplay, were found tobe effective in preventing pinion bearing seizure.

Endplay(mm)In order to prevent pinion bearing seizure and increase
the reliability of gear units, it is important to ensure thatsufficient endplay is maintained with the pinion bearings during rotation (Fig. 1). Bench rotation tests wereconducted to measure changes in endplay, variations in
endplay caused by changes in temperature of the pinion
bearings and the peripheral parts were estimated throughcalculation.
Results showed that the lower the temperature of thegear oil, the greater the reduction in endplay immediately
after the rotation start of the shaft. In addition, the difference between measured and calculated endplay was 0.02
mm at most, confirming that the tendency of their variations
were almost the same (Fig. 2).
The rotational torque of the pinion bearings and thetemperature of each component were also measured. It
was found revealed that, when the (calculated) endplay
reduced to near 0mm due to changes in temperature of
the pinion bearings and its peripheral parts during rotation, seizure occurred, and the bearing shaft torque andtemperature suddenly rose (Fig. 3).

Seizure occurs

80

70
60
10
8
6
4
2
0

Seizure occurs

50

10min
Time

Fig. 3 Variation in bearing temperature, torque and endplay
until burn-off seizure occurs

Annual Report 2017-2018

COST REDUCTION

Railway Technical Research Institute

12. Development of early restoration and reinforcement technologies for embankments damaged by natural disasters• A effective method for rapidly restoring and reinforcing embankments damaged by severe weather
events, using a combination of earth bank reinforcing materials, gabions and drainage pipes has beendeveloped, and an accompanying design and work manual has been drafted.
• The proposed restoration method increases resistance to rain damage 1.7 times and 1.5 times toearthquakes.
• The proposed method can reduce work time by approximately 30%.
Up until now, when embankments collapsed due toearthquakes or torrential rain, temporary measures, suchas application of large sandbags, were used to reconstitutethe earthwork’s profile, then, whilst trains continued to run,repair work was carried out on the embankment. Thisapproach requires the erection of temporary earth retaining
walls, on-site inspections and implementation of speed
restrictions.
As such, a rapid restoration and reinforcement method
to improve embankment performance was developed
which splits the work: a stock of gabions is kept on standby
in order to quickly restore the earth bank, whilst earth bankreinforcing materials and drainage pipes can be added
later while trains are running (Fig. 1). The proposed method
requires 30% more time than it takes for completion of
the first phase of immediate emergency repairs under the
existing method, however, the total completion time of the
new method is 30% shorter. In addition, the new method
can lower costs by approximately 30-60%.

With a view to verifying the long-term stability of the
proposed construction, cyclic loading tests of repeatedtrain loads and FEM analyses were conducted over 3
years on a class-4 line (max. axle load 14t, max speed
85km/h). The residual subsidence after this period was
8 mm, validating the design as an alternative to an earth
embankment as a supporting structure for ballasted track.
In the functional tests conducted on the proposed structure
shown in Fig. 2, the high draining capacity of the gabions
meant that resilience to circular slip in torrential rain was
1.7 times higher than the existing construction method,
validating the improvement in rainfall resistance.
In addition, the combined use of gabions and soil reinforcement meant that acceleration before collapse was
1.5 higher than before, which confirmed the consolidating
performance of the gabions and earthquake-resistanceof the proposed construction method. The insights fromthese results were used to compile an accompanying user
manual.

Installation of gabions

Existing method(collapsed after rain only without vibration)
Initial shape
Land preparation
Section is preserved(trains can be operated at this stage)

Projected state after restoration
using this method
Proposed structure(gabions+ earth bank reinforcing materials)=> impact of rain and input shaking of 900 gal.

Filling/compaction

Soil reinforcement

soil reinforcement work

Completion

Fig.1 Proposed construction work flow

Annual Report 2017-2018

Fig. 2 Functional verification testing increased
resistance to rain fall and earthquakes

15

Major Results of Research and Development

13. Tunnel reinforcement method using improved performance
ground reinforcement rock bolts• An improved performance rock bolt was developed that is effective even in loosened ground.
• Test work confirmed that the new design was workable and maintained axial force over the long term.
• Compared to existing rock bolts, the new design can reduce work related costs by about 40%.

Existing rock bolt
①Absence of grout
around tip of bolt

Area of loosened ground

Filler mortar②Absence of fixing
strength in area withloosened ground

Frost heaving pressure

110

Axial force at headof RB(kN)

Reinforcement work on tunnels subject to earth pressure is usually carried out using rock bolts, however, incases where the ground continues to weaken, the effectiveness of this type of measure is limited because it
is not possible to maintain fixing strength. Consequently,
improved performance rock bolts were developed, which
can be just as effective on softened ground.
The problems encountered with existing rock bolts,
included absence of filler mortar around the tip of the rockbolt, and lack of fixing strength when inserted into softened
ground around the tunnel. The new rock bolts have additional packers and expansion mortar injected aroundthe tip of the rock bolt, which maintains fixing strengthof the tip. Permanent grouting is also injected into theweakened surrounding ground, which is the source of thepressure, bringing the loosening ground problem undercontrol (Fig.1).
Based on the results of calculations performed on asingle track tunnel, the effectiveness of the performance

Improved
performance
RB

100
90
80
10/22

Existing
RB
1/21Month/day

4/22
RB：Rock bolt

Fig. 3 Change in axial force after test work

improved rock bolts in preventing deformation, is 2.6 times
greater than the existing bolts, compared to the case where
three times as many existing rock bolts were used (Fig.
2). Given that about three times as many existing rockbolts are required, using the newly developed bolts can
reduce costs by approximately 40%. A test using the newly
developed bolts was carried out on a tunnel on a disusedline in Hokkaido.
Results of a trial on a tunnel subjected
to pre-stress of 100 kN over one winter,
Performance improved rock bolt confirmed that the newly developed rockbolts were able to retain axial force more
①Fixing strength ismaintained
effectively than the existing type (Fig. 3).
(rock bolt packers +expansion mortar)
In addition, an accompanying design /work manual was drafted.
This research was financially supported by the Japanese Ministry of Land,
Rock bolt
packers
Transport, Infrastructure and Tourism.
②Reinforcement of
weakened area of ground(permanent grouting injection)

Fig. 1 Comparison with existing type of rock bolt
No rock bolt (RB)Existing type of RB

Performance 3x number of existing RB
improved RB (2x(cross section area)x1.5(pitch)
Displacement
100

62mm

42mm

10mm

13mm

-20mm

-52mm

-49mm

Controlled
displacement

2.6 times

Equivalent

80
60
40
20
0
(mm)

Fig. 2 Evaluation of effectiveness of displacement control through numerical analysis

16

Annual Report 2017-2018

Railway Technical Research Institute

14. Simple catenary designed for running speeds of over 300
km/h• A simple catenary has been developed with fewer components and good maintainability for lines withrunning speeds of over 300km/h.
• Tests on a revenue line confirmed that the contact loss ratio and contact wire uplift were both within
admissible limits, and that the new design posed no problem for the current collecting function of the
new system.
Auxiliary messenger wires on Japan’s Shinkansen line
heavy compound catenary systems are gradually coming
the time having to be replaced on a large scale. This isbeing used as an opportunity to replace incumbent installations with simple catenary systems on lines with runningspeeds below 300 km/h. Interest has been growing in themeantime, to have simple catenary systems introduced onlines with running speeds of over 300 km/h. Consequently,
two types of simple catenary system designed for operating
speeds over 300 km/h were developed (Table 1).
Compared to heavy compound catenary systems, theproblem with simple systems was that at speeds of over
300 km/h there is a risk for vertical pantograph vibrations toincrease in the intervals between masts, which hinders current collection. As such, the overall tension of the catenary
was increased above the normal simple catenary systemlevel in order to increase the spring constant of the contact
wire in the middle of the span between masts, thereby
controlling the vertical vibration of the pantograph. Two

simple catenary designs were developed, one for runningspeeds of 320/km/h and the other for 360 km/h (Fig.1).
For the 320 km/h design, in order to ensure that thewave propagation speed in the contact wire allows stablecurrent collection at 1.4 times the standard speed, the selected contact wire had a cross sectional area of 170mm2
and was tensioned to 22.54kN.
For use at 360km/h, the cross sectional area of theselected wire was 130mm2 even though this reduces themaintenance margin against frictional wear, which wastensioned to 24.5kN.
The two designs were tested on a revenue line to verify
their current collection performance. Results confirmedthat the contact loss ratio and contact wire uplift were bothwithin target values, and that the new design did not posea problem for current collection. In addition, tests demonstrated that the state of frictional wear and workability of
the new design were also satisfactory (Fig. 2).

Table 1 Overview of high speed catenary systems on Shinkansen lines

In the region of
250 km/h

Type of catenary
systemCompound catenary
system
Simple catenary
system

285km/hHeavy compound
catenary system

Large current capacity
high speed simple
catenary(total tensile force 49.0 kN)

320 km/h use 170 mm2
cross-section contact
wire(total tensile force 53.9 kN)

Messenger wire

5
0
100

Contact wire
Uplift [mm]Contact wire

Simple catenary system(new design)

Fig. 1 Schematic and image of developed catenary system

Annual Report 2017-2018

Contact loss
ratio[%]

10

Compound catenary system

With proposed ※catenary system
360 km/h use 130 mm2
cross-section contact
wire(total tensile force 53.9 kN)※ after completion of functional performance verification in high speed running tests

Messenger wire

Auxiliary
messenger wire

360km/hHigh-tensile force heavy compound catenary

High speed use simple
catenary for new
Shinkansen bullet-train
projects(total tensile force 39.2 kN)

Existing catenary wire

320km/h40

Measured value Target value below 10%
Calculated value

200

300

Speed [km/h]

400

Measured value Target value below 100mm
Calculated value

20
0
100

200

300

Speed [km/h]

400Fig. 2 In-line tests (360 km/h)

17

Major Results of Research and Development

15. Decision making system for economical mid-term track
maintenance plans• A system has been developed to optimize five-year maintenance plans for track irregularity and ballast
replacement.
• This system makes it possible to decide track irregularity maintenance and ballast replacement plansthat reduce the total cost of maintaining tracks to a satisfactory level over the medium term.

543Inspection

Track irregularity
measurements

2

First year
Maintenance
Maintenance plan targeting
optimal track condition
after five years

D

C

Ballast replacement
AnnualAnnualMTT
Section No. 1 2 3 4 5 Section No. 1 2 3 4 5
23
21
25
22
27
23
205
24
207
25
214
27
Mid-term
230
maintenance 28
planStandard deviation for longitudinalirregularity after five years.(mm)In order for track maintenance and management to be
more efficient, it is important to make the, “inspection,
diagnosis (level of deterioration), maintenance plan preparation, maintenance implementation” cycle as functionallyefficient as possible. Consequently, discussions beganon how to effectively exploit track irregularity data etc.
collected by either track inspection cars or commercial
trains in order to develop a system that would propose
maintenance plans for short to medium and long term
periods.
As a result, a medium term maintenance planningsystem was developed to plan both ballast replacement
and maintenance for track irregularity for 5-year periods.
Figure 1 shows how a yearly maintenance planningsystem functions according to the 5-year maintenance plan
decided by this system, upgrading track maintenance andmanagement more efficient.
In the developed medium-term maintenance planningsystem, the state of deterioration of the track is diagnosed
on the basis of past maintenance and track irregularity
data, from which sections of ballast that require replacement are extracted. Ballast replacement prioritization is
calculated on the basis of savings to be made on the costof track irregularity maintenance by replacing the ballast.
If the maximum possible maintenance for each year forballast replacement and track irregularity maintenance isattributed, then the plan decided by this system will ensure

MTT : Multiple Tie
Tamper17km/yr
10km/yr

2.5

Satisfactory
conditions

2

1.5

Optimum : ballast replacement
125m, MTT17km/yr

0

125

250

Length of sections requiring ballast
replacement over one year (m/yr)

Fig. 2 Example of mid-term maintenance plan trialthat the track is in best condition after five years (annual
ballast replacement and track irregularity maintenance).
Then, since the relationship between the amount of maintenance and track condition can be analyzed (Fig. 2), it ispossible to decide the maintenance plan to maintain the
track to a satisfactory level at a lower cost. Apart fromdetermining the sections requiring maintenance to manage
track irregularities over a year, use of the collected data
allows the plan to be reviewed etc., and can beconnected to the newly developed management
and maintenance planning system to update annual plans, in order to continuously improve theefficiency of the management cycle.
The new system was introduced into the track
maintenance planning systems being developed byrailway operators, and brought into service in 2018.

Ongoing improvementof mid-term maintenanceplan and related track
conditionnpla
ce trackna),ten nt ceAaincemeenanmDiagnosis of track deteriorationtP
rm replamain
e
t
t ity
d
Track irregularity progressesisa
M all lar
Ballast condition diagnosis(b eguirr
Decision of annual maintenance plan

Track irregularity maintenanceFig. 1 Image of mid-term maintenance planning system

18

Annual Report 2017-2018

Railway Technical Research Institute

16. Rail head defect repair method with reduced work time
• An automatically controlled hot rail correcting machine was developed as a rail head defect repair
method.
• The new machine can reduce working time by 2/3 compared to existing methods, to within three hours.
• In order to generalize the use of this method, a “Working handbook” was compiled.
The method used for repairing rail head defects involves
localized removal of the damaged part of the rail head, andfilling the gap with molten steel. It is an inexpensive repair
for the rail damage method and railway companies havetested the method and have now begun to use it in earnest.
In this method, heat is only applied to the affected partof the rail head, therefore, because of thermal contraction,
the rail will dip after cooling (Fig. 1). Consequently, after
pouring the molten steel on the rail to mend the defect,
the repaired part of the rail is bent upwards whilst it is stillhot (hot rail correction), in anticipation of the dipping in
the rail, preventing the thermal contraction effect (Fig. 2).
Nevertheless, the following issues have arisen withthis hot rail correcting process so far, which will form an
obstacle to the method being adopted generally:
Significant dipping in rail caused by thermal contraction

Repaired partFig. 1 Thermal contraction of repaired part

Hydraulic cylinder

Hydraulic cylinder

Fig. 2 Bending upwards the repaired partof the rail by hot correcting

Hydraulic cylinder
SensorPreparatory work Welding work Finishing work Follow up work

Current system(Normal plan) 18

60

120

30 228 mins

67 mins shorter
Automatic 15
control
0

68

60

18 161 mins

50 100 150 200 250
Work time (minutes)

Reduction by half of finishing work time

Fig. 4 Resulting shorter work time(1) The operator must visually measure rail deformation
using a custom-designed special ruler whilst operating ahydraulic pump, which requires a high degree of skill andexperience.
(2) There are cases where the rail is bent upwards too
far, which increases the time required for rail grinding work,
while it is necessary to keep work time to around 4 hours.
In order to deskill the rail head repair process, anautomatically controlled hot rail correcting machine wasdeveloped (Fig.3).
With the new machine it is possible for an ordinary
operator (without the specialist skills) to accurately andquickly carry out the hot rail correction work. The machineis also simpler with only one hydraulic cylinder, in order tomake it lighter and less expensive. Trials where the machine was used on actual in-service railway lines confirmedthat repairs could be completed in approximately 160
minutes. Removing the risk of bending the rail upwards
too far makes the new method 60 mins shorter than theexisting method (Fig. 4).
In addition, in order to support the creationof a qualification system for operators using
this method which is essential if it is to be usedby operating companies throughout Japan, a“work manual” was compiled containing the
key points on how to apply the rail head repair
method.

correcting possible with single hydraulic cylinder
Fig. 3 Outline of automatically controlled hot rail correcting machine

Annual Report 2017-2018

19

Major Results of Research and Development

17. Wireless train control systems designed for regional
railways• A train control system has been developed, designed for regional railways using wireless communication
which does not require track circuits and wayside signals in station yards.
• Trains are protected when running from one station to the next by an onboard device installed with a
database.
• Since a generic wireless LAN is used, and IP telephone connection can be used for ground facility-train
communication
Current train control systems designed for regional
railways includes electronic blocking systems, and train
control systems using area-specific radio communications
developed by RTRI, which both still require track circuits
and wayside signaling equipment. In the proposed newly
developed system, the train position recognized by the
onboard system is transmitted by radio to a central management device, which determines the section within which
the train can operate and transmits this information back to
the train, which does not require track circuits and wayside
signaling equipment. The train position in the developed
system is recognized using the ATS-Dx function of theonboard database, developed by RTRI.
ATS ground coilfor SPAD prevention(signal passed at danger)

Radio device

Onboard device

StationStationATS onboard
deviceTrack circuit(for train
detection)

Wayside signal
Interlocking
deviceStation control
terminal

Communication
line

Interlocking
deviceCentral device(operational
management)

Station control
terminal

Fig. 1 Schematic of existing system (with radio communications in specific areas)

ATS-Dx ground coil(train position data)Radio
deviceWayside equipment is composed of ATS ground coils forabsolute position detection, radio devices, and the station
control terminal which interfaces with points machines andlevel crossing equipment (Fig. 1). Within station premises,
a generic 5.6GHz wireless LAN is used which does not
require a radio station license and has the advantage ofproviding track-train radio communication by IP telephone
connection, even for sections not equipped with train radio.
The bandwidth of control information to be transmitted issufficiently small for wireless networks to function, therefore, if the radio is adequately designed, it is possible toensure stability.
A special feature of this system is that the section
between the departure signal in the departure stationand the platform in the destination station is occupied
as one block, therefore, even if there is a problem inthe onboard or ground equipment on route, the train is
protected up to the destination platform.
The specifications of the system were defined andbased on these findings and tests were conducted witha prototype system to check basic functions such as
block control, control of passing and turning at stations,voice communication and emergency response. It was
confirmed that even when the radio was unstable, safety
was ensured. In the future, tests on commercial lines
are to be conducted.

Onboardequipment② Station control terminal

Central management① (control) device

StationStation
ATS-Dxonboard device
Communication line
Stationcontrol terminal

Track circuit
Trackside signaling
equipment②Stationcontrol terminal①Central management(control) device(interlocking functions/block function)

New equipment
Existing equipment

Fig. 2 Schematic of proposed new wireless train control
system for regional railways

20

Fig. 3 Station terminal device and central management
deviceAnnual Report 2017-2018

Railway Technical Research Institute

18. Concrete deterioration control using hydrogen-ion typegeopolymer• A method to synthesize hydrogen-ion type geopolymer with a high-performance concrete deterioration
inhibitory effect has been developed.
• The new compound is as effective against ASR concrete deterioration as existing lithium based
products, for one-fifth of the material cost.
In response to the commonly occurring Alkali-silica
reaction (ASR) deterioration to concrete, RTRI developed
a protective lithium (Li+) type zeolite material based on
a compound using zeolite and lithium ion (Li+), known
for their effectiveness against ASR, which is now used inpractice. The issue with this compound is that the ingredient Lithium is expensive, limiting possible cost reductionof the product.
Investigations were therefore made with geopolymer
which has the same properties as zeolite and combines
easily with hydrogen ions (H+), focusing on cheap industrial
by-product and mineral admixture geopolymer technology,
and developing a hydrogen-ion geopolymer synthesizing
method which uses materials that are 1/5 to 1/10 the costof the existing lithium-ion zeolite combination.
In tests with a mortar to reproduce grout injection
into cracks, a cement paste containing the developed
Hydrogen-ion geopolymer was injected into holes (Fig. 1)

0.30

K＋
Na＋

H

H＋

on
on
Adsorpti Adsorpti
on H＋
Adsorpti

Desorption

Na＋
Desorption

The paste is injected into the concrete
body cause desorption of Hydrogen ions,while K+ and Na+ ions are adsorbed
reducing the pH of the concrete body.
Fig. 1 Specimen reproducing grout injection into cracks
and schematic showing how ASR process is suppressed

Annual Report 2017-2018

0.00

(1)

(2)

(3)
With adjunction of Li+
type zeolite

Desorption

0.10

With adjunction of H+
type geopolymer

pH is reduced

Paste injection

Effectiveness insuppressing
expansion

0.20

Without adjunction of
ASR controllingmaterials

Expansion rate(%)

40mm×40mm×160mm
φ6mm＋

and the expansion rate was measured. Results showedthat even though the developed Hydrogen-ion geopolymer
contained materials the cost of which was less than 20%,
it was just as effective in suppressing expansion as the
Lithium-ion zeolite (Fig. 2).
The target now is to develop the new grout for crack
injection to suppress ASR, for practical use within three
years, which should contribute to improving concrete
structure maintenance.

Fig. 2 Effectiveness in suppressing expansion due to ASR

21

Major Results of Research and Development

HARMONY WITH THE ENVIRONMENT
19. Voltage control method for DC electric traction system withvariable inductor• A DC feeding voltage control technology has been developed to allow more efficient use of regenerativeelectric power.
• With the new technique, voltage can be controlled to within approximately 25% of the rated value,
whilst the cost is about 20% of the latest existing technology.
Optimized control of feeding voltage supplying DC
electrified railway lines should generate energy savings
and result in higher efficiency of power supply.
Robust and inexpensive diode rectifiers (middle of Table1) widely used today cannot control their output voltage,
and although the newest PWM rectifiers (right side of Table
1) that are able to control voltage are being used in practiceas well, they are approximately ten times more expensive
than diode rectifiers.
Consequently, a new voltage control method has been
designed (left side of Table 1), composed of a voltage control device built with a voltage control circuit and a variableinductor (Fig. 1) connected to a rectifier transformer with arectifier installed on both sides. This variable inductor type
method is based on a technology patented by the Tohoku
Electric Power Co., Inc. The equipment configuration anddesign method were then adapted for use on the railways.

Contrary to PWM rectifiers, the new method has someconstraints, for example it does not allow reverse power
flow (so regenerated power cannot be reused as a powersource in stations etc.), however, it can reduce costs toapproximately 20% of the latest existing method (about
1.5 to 2 times the cost of diode rectifier).
A prototype with a small capacity of rated current (500 A)
was built (Fig. 1), to validate the function and effectivenessof the new method. Results confirmed that the rated voltage (1500 V) could be controlled to approximately withina maximum of 25% (approx. 400V) (Fig. 2). ICT is used
to exchange data in real time between rolling stock andsubstations, which should allow energy savings to be madeacross the whole DC railway network. The new method
can also be used as a measure against voltage drops in
the DC electric traction system.

Table 1 Composition and position of new control method equipment
New control method

Type

Rectifier transformer

PWM rectifier

Diode rectifier

Rectifier

Rectifier transformer

RectifierThree-phase AC

DC

Rectifier transformer

PWM rectifier

Voltage control
deviceEquipment
configuration

Variable inductor＋

Control circuit

Three-phase AC of electric
power company

DC of overheadcontact line

DC

Voltage control

Available

Not available

Available

Reverse power flow
Relative priceNot available
1.5～2

Not available
1（baseline）

Available
10

Position

Newly developed voltage control technology

Widely used

Latest technology used in practice

Variable inductor

3.1m

2.1m

Output voltage(V)

1800

Controlequipment

1500
1200
900 Approximately
400V(25%)
600
300
0

Total weight 14.9ｔ

750kg

Fig. 1 Prototype voltage control equipment

22

Three-phase AC

0%

20%

Voltage can becontrolled within
this range

40%

60%

80%

Rectifier output power

100%

Fig. 2 Voltage control characteristics of new control method

Annual Report 2017-2018

Railway Technical Research Institute

20. Model for predicting wayside noise considering soundreflection from structures close to the railway track• A model for predicting wayside noise has been designed which takes into account the influence ofsound reflected or shielded by cut slopes, overpasses and other buildings.
• This model can be applied for investigating noise control for complex situations, for example if a newbuilding or overpass has been constructed adjacent to railway tracks.
In order to evaluate environmental impact assessments
and countermeasures to reduce noise, it is necessary tohave a model for predicting wayside noise which can beapplied to various situations, whereas existing prediction
models were mainly designed to estimate the noise fromtrains passing over viaducts.
Consequently, in order to extend the scope of application of these existing models, the influence of waysidestructures such as cut slopes, overpasses and buildings,
etc. on noise propagation was evaluated through model
acoustic tests and actual running tests, and the results ofthese tests were used to build a new model.
A noise source model to be applied to cut sections wasconstructed, taking into account the noise reflecting andshielding effects of noise barriers, slopes and carbodies.
Similarly, the model was applied to complex situations
with overpasses and buildings, taking into account thenoise reflection and shielding effects of the underside ofoverpasses and building fronts (Fig. 1).
Using a spread sheet software the influence of reflectedsound was calculated as a reflection correction of a finite
flat surface, and the influence of sound shielding was
calculated as a shielding correction of multiple walls andrectangular barriers. The difference between resulting

predictions made using this new model and results ofactual model tests on the influence of an overpass and abuilding, were within 1.5dB, confirming the validity of the
new model (Fig. 2).
The present model will make it possible to estimate noise
even in complex conditions, with adjacent overpasses
and buildings. It should also contribute to evaluation ofcountermeasures against noise when new overpasses orbuildings are constructed in the vicinity of railway tracks.

Benchmark: no overpass and no building
Overpass
Measurement (model test)
Overpass

Reflection

Railway bridge

Estimation

Building

Building

ShieldSound receiving point

Difference:less than 1.5dB

Overpass+ building
-2

0

5

10

Evaluation of sum power of noise from different passes

Noise variation (dB)

Fig. 1 New model for predicting wayside noise

Fig. 2 Example of evaluated influence of building
and overpass

Annual Report 2017-201823

Major Results of Research and Development

IMPROVEMENT OF CONVENIENCE
21. Active bogie angle steering system ensuring bothrunning stability and reduced lateral force• An active bogie angle steering system has been developed which can reduce the yawing moment ofa bogie by 77% and the average lateral force by 56% in curved sections.
• The new system includes a robust failsafe function, and can be fitted onto existing vehicles.
A new active bogie angle steering system has beendeveloped, which not only reduces the lateral force incurved sections by controlling the bogie angle of vehicles,
but also ensures the running stability in straight sections
by acting as a yaw damper. Unlike the existing system,
the present system does not require linking devices tobe installed under the primary suspension, avoiding the
problem of added weight to the bogie.
The developed steering system is composed of threeparts: a steering controller which detects curves andgenerates the steering command, steering actuators thatcan be activated to act as yaw dampers to maintain therunning stability if necessary, and a mechanical device
which detects the bogie angle to prevent reverse steering
and wrong steering on straight sections (Fig.1).

In simulation bogie rotational resistance tests conducted
on a commercial railway line, it was demonstrated that thesteering control system was able to reduce the yawing
moment of the bogie by 77% (Fig. 2). The results of hunting
stability tests confirmed that the new steering actuator wascapable of maintaining the same level of running stability
as the current yaw dampers. Trial running tests conductedon the RTRI test line on curves with a radius of 160m
confirmed that the average lateral force can be reducedby 56% in curved sections (Fig. 3).
This system is suitable for express trains that are
subject to very high lateral forces when running throughsharp curves or when running speeds on curved sections
are increased. The system can also be fitted to existingvehicles equipped with yaw dampers.

Prevention device of reverse steering/steering in straight sections

Steering actuator

20
10

12

-10
No steering control
Steering control
510Time (s)15

20

Fig. 2 Effective reduction in the yawing moment of the bogie
demonstrated in bogie rotational resistance tests simulating
on a curve section.

24

Average lateralforce reduced byapproximately 56%

10

Yawing moment of thebogie reduced byapproximately 77%

0

-20
0

Average lateral force on outer rail in curve[kN]

Yawing moment of the bogie (kNm)

Fig. 1 Active bogie angle steering system

8
6
4
2
0

No steering control

Steering control

Fig. 3 Effective reduction in the average lateral force in therunning tests at RTRI.

Annual Report 2017-2018

Railway Technical Research Institute

22. Improvement of the effectiveness of tunnel entrance
hoods by enlargement of their cross-sectional area toreduce micro-pressure waves• A cross-sectional area ratio of the tunnel entrance hood to the main tunnel has been proposed whichis effective in reducing micro-pressure waves.
• It has been found that if the tunnel-entrance-hood-to-main-tunnel cross-section ratio is increased to
2.5, the hood will still be effective in reducing micro-pressure waves even if all side-wall openings areclosed, and the hood is less than 40m. It was also found that for cases where the extension is over
40m, a graduated increase in the cross-sectional area ratio of the tunnel entrance hood to the main
tunnel is also effective.

(a) Existing tunnel hood

Results of these trials showed that on hoods under
40 m in length, raising the tunnel-hood-to-extension
cross-sectional area ratio to 2.5 increased the reduction
effect compared to the existing design, even if side wall
openings were closed (Figs. 3 and 4). For hoods of over
40 m in length, a graduated increase in this ratio over thelength of the hood was even more effective (Fig. 4). The
two proposed solutions with larger and graduated crosssection ratios offer the added advantage of not requiringside openings along the tunnel hoods.

Maximum pressure gradient ratio

As Shinkansen running speeds increase, solutions haveto be found to reduce micro-pressure waves emitted fromtunnel portals. One approach is to install a tunnel entrance
hoods on tunnel portals at the point of trains entry. As
running speeds exceed 320 km/h however, the tunnelhood that would have to be added for these measures tobe effective, would be longer than the 30-50m currently
applied. This limitation added to the extra cost of extra
work, and in certain cases, these countermeasures would
not be feasible.
Consequently, model tests were carried out on newproposed designs (Figs. 1 and 2) that could be more
effective unconcerned about the existing specifications(currently, the cross-sectional area ratio of the hood to themain tunnel are between 1.4-1.6, and openings are added
to the side wall of these extensions).

1
0.8
0.6
0.4

Train nose length : 15m
Train speed : 360km/h
Side wall openings : all closed
Length of tunnel entrance hood : 50 m

0.2
0

1
1.5
2
2.5
3
Ratio of tunnel entrance hood / main tunnel cross-section(c) Graduated increase in cross-sectional area ratio
Fig. 1 Tested attenuation methods

Model train
Tunnel entrance hood modelFig. 2 Image of experiment set up for model test of tunnelhood with graduated increase in cross-section ratio

Annual Report 2017-2018

Fig. 3 Relation between tunnel entrance hood cross-sectionand effectivenessMaximum pressure gradient ratio(b) Increased cross-sectional area ratio

1

Cross-section ratio 1.4, side wall withdiscrete window-type openings
Cross-section ratio 2.5, all side openings closed
Graduated increase in cross-sectional
area ratio, all side openings closed

0.8
0.6
0.4
0.2
0

Train nose length : 15m
Train speed : 360 km/h
0

10
20
30
40
Tunnel entrance hood length

50

Fig. 4 Relation between tunnel entrance hood length andeffectiveness25

Major Results of Research and Development

23. Communication network and train operation simulator fordesigning train control system using radio communication• A simulator was developed to evaluate train delays and stability of the train control system using radio
communication.
• The simulator will help to reduce the cost of designing radio communication networks and also satisfy
the requirement of ensuring transmission quality and recovery from train delays.
In train control systems using radio communication , asection is predefined as a “zone” by each base station andthe base stations communicate with multiple trains locatedin their zone at the same time. Each base station allocates“timeslots” which are brief windows of time given to eachtrain to be able to communicate in real time. When traffic
density is very high and there are not enough timeslots
for each train, trains without allocated timeslots are forced
to stop. Therefore, when radio communication networks
are designed, it is necessary to take into account bothtransmission quality and the need to avoid train delays
due to lack of timeslots. Up until now, radio communication
network design focused solely on transmission quality,
which meant that excessive communication capacities
were provided to endure stable transportation service.
Consequently, RTRI developed a “Telecommunications
and train operation simulator for train control systems using
radio communication” which evaluates transmission quality
taking into account train operations. This method combined
the “Train communications network simulator for train

control systems using radio communication” for evaluating the stability of transmission quality of the train control
systems using radio communication with “Train operationand passenger flow simulator,” both previously developedby RTRI (Fig.1). It is now possible to quantitatively evaluate the load on radio communication networks, and train
delays not only for ordinary but also for disrupted situations which represent severe operating conditions for train
control systems using radio communication. A method was
also devised to detect sections vulnerable to deadlocks
which force trains to stop due to lack of timeslots.
In addition, a flow chart was produced for designingradio communication networks using the developed
simulator, etc. (Fig. 2). When new train control systems
using radio communication are introduced, this flow chart
will make it possible to ensure that the designs satisfy theneed for transmission quality and capacity to recover fromtrain delays. It can also ensure the lowest cost design forradio communication networks.

Lowest cost design
Radio network design compliant withtransmission quality requirements

Radio communication network design, operational planning, etc.
Communication network

Base station
Timeslot

StationIn cases where
standard
requirements are
not satisfied,increase in
number ofbase stations

StationTelecommunication and train operation simulator
for train controlusing radio communication
Communication network
simulator for train
Quality of radio
control system using transmissions
radio communication
Simulate of radio
communication
network

State of train
operations

Train operationand passenger flow
Simulator
Simulate train
operation

Likelihood of radio transmission error

Evaluation of probability of deadlock
occurring due to lack of timeslot
Likelihood of deadlock

Analytical evaluation of train operation
Likelihood of insufficient timeslots

Evaluation of train operation by simulation
Recovery ability from train delay

Evaluation of delay in transmission by simulation
Load on radio communication network, recovery ability from train delay, etc.

Fig. 1 Telecommunication and train operation simulator for
train control using radio communication

26

Likelihood of train delay due
to transmission delay

Fig. 2 Flow chart for system design

Annual Report 2017-2018

Railway Technical Research Institute

24. Method for supporting decisions on planning
Shinkansen transport services based on forecast
demand fluctuations• A method to forecast half-hourly demand fluctuations on a daily basis was developed based on pastactual Shinkansen ridership records, calendar arrays and large events scheduled to be held nearstations.
• With the developed decision-making support system for planning Shinkansen transport services, it
is possible to determine the need to operate or not daily pre-planned extra trains based on the resultof demand fluctuation forecasts.

Separation using statistical method Weights for M days

×

Weight 1M

Planning schedule

Calendar array

Information about largescheduled events×

System for supporting
decisions on planning
Shinkansen transport services

Input data
Sun Mon Tue Wed Thu Fri Sat＋…＋

WeightJ1

Development of forecasting
method for future demand fluctuations
Forecasting with basic demand fluctuations
and forecasting model of weight

Weight JM

Forecast demand
fluctuations

Formulation of forecasting model of future weights
based on relationship with calendar array andtionlarge scheduled events held near stations
nta

Constant
regardless of day

Days

Basic fluctuation J

Weight 11

Basic fluctuation 1…

Based on ridership
records…

Number ofpassengers

Demand fluctuations for M daysTime

based on the relationship between the weights, calendar
arrays and information about large scheduled events, anequation was formulated to forecast future weights. By
combining forecast weights with the basic fluctuations, future daily demand fluctuations were forecast. Comparisonof forecast results with actual data, confirmed a high levelof accuracy (correlation coefficient of over 0.8) for over
90% of the examined period of 172 days (Fig. 2).
The developed Shinkansen transport planning support
system which incorporates the demand forecasting method
can be used to calculate the load factor between all stations along the route of all scheduled trains, based on theforecast demand fluctuations. By using this system, it istherefore possible to determine whether pre-planned extra
trains need to be operated.

Number ofpassengers

In order to formulate Shinkansen transport planningwith high passengers’ convenience, it is necessary to accurately forecast Shinkansen demand which constantly
fluctuate. However, it was difficult to forecast such detailed
passenger demand with conventional approach because
it targets demand of average day.
Consequently, a method to forecast half-hourly fluctuations in Shinkansen passenger demand was developed
using actual ridership records, calendar arrays, andinformation about scheduled large local events (Fig. 1).
First of all, daily demand fluctuations were calculated
from collected ridership records. Using a statistical method,these fluctuations were separated into several ‘basic
fluctuations’ which were constant regardless of day, and‘weights’ of each basic fluctuations were estimated. Then,

Regular train
Pre-planned extra
train scheduleDays (future)

Time
me
ple
Im
Output of forecast load factor andrecommended extra trains to be operated

April 1, 2019 : Load factorof regular train X is 140%

April 1, 2019 : Operation of
extra train Y is recommended

Actual data

Forecasts

Number of passengers
3:00
5:00
7:00
9:00
11:00
13:00
15:00
17:00
19:00
21:00
23:00
1:00

Number of passengers
3:00
5:00
7:00
9:00
11:00
13:00
15:00
17:00
19:00
21:00
23:00
1:00

Fig. 1 Outline of the developed method for forecasting demand fluctuations and system for supporting decisions on planningtransport services
Actual data

Correlation
coefficient：

0.984

Forecasts

Correlation
coefficient：

0.985

Weekday example
Time

Holiday example
Time

Fig. 2 Example of accuracy verification for forecasting half-hourly fluctuations in Shinkansen passenger
demand (for same section (route))

Annual Report 2017-2018

27

Major Results of Research and Development

BASIC RESEARCH

25. Method for measuring dynamic deformation of brakedisc• A method has been proposed for measuring dynamic deformation on the friction surface of brake discs
heated to high temperature during high speed rotation, which up until now has been difficult to do.
• Better understanding of the dynamic deformation of the disc and the pad can be used for verifying
their design and examining relevant mechanisms.
The high speed vehicles that are the trademark of
Shinkansen lines use disc braking. This type of braking
method involves the brake pad being pressed onto thebrake disc generating frictional force. Consequently, thefaster the speed, the greater the heat produced by thisrubbing, which in some cases leads to lower braking performance. Observations made of the disc in this mechanism
using a thermal-camera show that the spots where heatis generated constantly vary over time. However, there
is no insight, including from other industries, about themechanisms underlying the dynamic deformation of discs,
which is another factor thought to contribute to lower performance. This lack of knowledge is one of the obstacles
to making progress in brake device assembly researchand development (discs, pads, calipers).
The method described here was therefore proposed
to measure the dynamic deformation of the brake disc inDistance of sensor 1.5mm

operation using a vibration-absorbing table and electrostatic capacitance type sensors capable of measuring
displacement without contact (Fig. 1).
Through in-depth dynamic deformation analysis of thedisc in operation from different rotation angles, it is possible
to visualize dynamic deformation (Fig. 2). Through theseinvestigations, it was possible to clarify: the cyclic appearance of deformation on the friction surface, the differing
aspects of dynamic deformation depending on the disc/pad configuration and microscopic deformation related tothe distance between disc lock (fastening) bolts.
The proposed measurement method will be useful not
only for design verification of the shape and mechanicalstructure of brake pads and discs, but may also contributeto clarifying frictional mechanisms and evaluating braking
noise.

-300 -200 -100 0
Displacement[μm]

100 200 300

Displacement
amplitude
600μm
270km/hDuringdeceleration

120km/hDuringdeceleration

Disc(a) Existing disc and pad
Displacement sensor

Displacement
amplitude
300μm

Pad

Vibration-absorbing table

270km/hDuringdeceleration

120km/hDuringdeceleration(b) Newly designed disc and pad
Fig. 1 External view of measuring device

28

Fig. 2 Example of visualization of dynamic deformation

Annual Report 2017-2018

Railway Technical Research Institute

26. Current collection HILS system enabling simulated
running tests• A current collection HILS system was developed which enables simulated running tests to be conductedusing stationary pantographs to examine the interaction between pantographs and overhead contactlines.
• Verifications were made to check that the system was able to reproduce OCL vibrations up to 20 Hz
generated at running speeds of 300 km/h by the span length between support points and distance
between droppers.
• The HILS system could reduce the time required to develop new pantograph designs.
In the process for developing pantographs, before actual vehicle tests are conducted, each component of the
new pantograph has to be tested on test rigs for resilienceof structural members and ability to comply to the vibrating
overhead contact line (OCL). Existing test rigs however,are unable to fully reproduce the vibrations generated by
the swaying movement of the OCL as a pantograph moves
along it, as in real running conditions. This means that in
actual vehicle tests, some pantographs may not produce
the same performance as verified in preliminary functional
bench tests, and until now, the only way to resolve design
problems was to carry out repeated adjustments and tests.
Consequently, a current collection HILS (Hardware
In the Loop Simulation) system was developed whichenables simulated running tests with stationary pantographs to examine the interaction between pantographs
and overhead contact lines (Fig. 1). The system calculates
the OCL vibration that would be generated by a passing

pantograph during running in real time, which controls thevibrating equipment, reproducing the vibration conditionsof a pantograph running under an OCL.
A comparison of the results obtained from the test
equipment reproducing running conditions at 300 km/h
with target values (set by simulation of the overhead line /pantograph system) showed that the frequency response
up to 20Hz correlated well, and confirmed that the simulated running test of a pantograph was able to reproduce
conditions which could examine the influence of OCL
vibration due to the periodicity in OCL structure and wave
propagation generated by the pantograph under running
conditions for speeds up to 300 km/h (Fig. 2). Given thatthe conditions reproduced in these stationary tests arevery close to real train tests, the newly developed systemshould be able to reduce the time required to develop new
pantograph designs.

Vibration equipment (reproducing overhead line vibration)

Real train test
Measurement of complianceto overhead line / component
strength, etc.
of
Span length between
ction lator
supporting points
rod u simu
Repns with tionary
Distance between conditio the sta ment
droppers
and st equipteControl command

Contact force

Overhead line
vibration

Overhead line
vibration simulator
eed

Running sp

Real pantographCalculation of overhead line
vibration according to actual
measured contact force

Evaluation of component
strength / tracking, etc.

80

HILS test

105

Target value

60

HILS test

Target value

100

40
20
0
0

Change in pantograph headvibration PSD (mm2/Hz)

Change in pantograph headvibration（mm）

Fig. 1 Outline of current collection HILS system

100

300
200
Distance（m）

400

10-5
0

Span length between supporting points
Distance between droppers

5

10
15
Frequency（Hz）

20

Fig. 2 Results of mock running test using HILS system (change in pantograph head vibration)

Annual Report 2017-2018

29

Major Results of Research and Development

27. Reproduction of meandering airflows under the
carbody through numerical simulation• Based on an analysis of airflows around a railway vehicle including the bogie, it was possible toreproduce the meandering airflows occurring underneath the carbody.
• Comparison of calculated airflows and wind tunnel test results showed that the tendencies in power
spectra for lateral airflow velocity fluctuations between the two were almost identical.
• The results of this work can be used to examine measures for reducing train oscillation in tunnels.
It has been shown using numerical simulations ofairflows around a simple shaped train model, that train
oscillation in tunnels is induced by meandering airflows
under the carbody floor. So far however, no quantitative
comparisons have been made using detailed investigations, or actual tests that also take into account the
influence of bogies.
Consequently, a numerical simulation of airflows beneath a carbody floor was carried out on a coupled trainmodel that included bogies (Fig. 1). The output of thissimulation was compared with the results of wind tunnel
tests (using a 1/8.4 scale train model on a moving belt)
which revealed that the power spectra of lateral airflow
velocity fluctuations showed the same tendencies, which
confirmed that it was possible to reproduce the meandering
airflows generated in wind tunnel tests (Fig. 2).

Investigations into the impact of modifying the bogie
shape confirmed that a completely smooth bogie generated
no meandering airflows, demonstrating that smoothing thebogie was an effective measure to reduce meandering
airflows.
Numerical simulation of the airflows beneath the vehicle
floors in a coupled train not only contributes to the development of carbody shapes that can reduce train oscillation intunnels, it can also be used as a tool to estimate airflows
around bogies, and to develop measures to reduce air
resistance of vehicles, snow accretion on bogies andaerodynamic noise from bogie parts.

Appearance of meandering airflow beneath coupled train

Calculation accuracy for 4-car consist with bogie

Reproduction of meandering airflow observed in wind tunnel tests
2.0

Non-dimensional conversion of flow
velocity based on train speed

0.0

Shape ofbogie part

Car No. 1

Car No.2

Car No.3

Shape of bogie part : bogie

Car No.4

Blue: low velocity region

Appearance of meandering
airflow beneath 3rd car

Power spectrum of lateralflow velocity fluctuation

Flow

10

Lateral flow velocity fluctuation
beneath carbody-1Wind tunnel tests ・1/8.4 scale・Moving belt

10-2
10-3

Calculation result
10-4

0

1
2
3
Non-dimensional frequency

4

Identical peak value, difference in peak frequency : 20%（Appearance seen diagonally from below）
Fig. 1 Fluid analysis considering bogie

30（Peak frequency converted for actual car at running speed of 300 km/h: approx.5 Hz）

Fig. 2 Comparison of fluid analysis and wind tunnel test

Annual Report 2017-2018

Railway Technical Research Institute

28. Wind tunnel tests reproducing the wind force resulting
from natural wind and vehicle velocity to evaluate
aerodynamic forces acting on railway vehicles• In order to evaluate the effect of wind force resulting from natural wind and vehicle velocity, a wind tunnel
test method was developed to evaluate the aerodynamic forces exerted on a moving vehicle model.
• It was found that on flat ground and on top of embankments, the influence of running on the sideforce coefficient is small, and it is therefore possible to evaluate the performance of a railway vehicle
in resistance to overturning in windy conditions by using a static train model.
Aerodynamic force evaluations are required to assess
running safety in high wind conditions, and in generalthey are made using wind tunnel tests. In these tests a
static model of a railway vehicle is placed on a piece ofrailway infrastructure, and the influence of the shape ofthe vehicle and the infrastructure, as well as aerodynamic
characteristics for the wind direction etc. are investigated.
This method however does not take into account another very important factor in aerodynamic force evaluationof a running vehicle, which is the influence of wind force
resulting from natural wind and moving velocity. Therefore,
with the purpose of validating the suitability of using a static
train model in wind tunnel tests, a moving model rig forreproducing the wind flows around a railway vehicle was
Collector

NozzleWind
Train modelMoving model rig
Direction of travel
Fig. 1 View of Wind tunnel test set up(RTRI’s large-scale low-noise wind tunnel)

installed in a wind tunnel, and a wind tunnel test method
was developed which can evaluate the aerodynamic forces
acting on a running vehicle under natural wind conditions
using a vehicle-mounted system (Fig. 1).
The wind tunnel test was conducted whilst varying thefollowing conditions: running speed (of the train model),wind speed in the wind tunnel and angle between the travel
direction and that of the natural wind. Wind-pressure taps
suitably distributed across the surface of the carbody wereused to measure pressure distribution. The side force,
which has the largest influence on overturning in all aerodynamic forces acting on a vehicle (the side force contributes
up to 70% of the overturning moment in critical conditions),
was evaluated.
The scale of the model was 1/60th, and its carbody
shape was the same as that of an ordinary commuter
train. The test was carried out both for flat ground andembankment conditions (Fig. 2).
The side force coefficients were estimated from thepressure coefficients measured on the model of thecommuter train. The maximum difference in side force
coefficient between the moving model tests and the static
model tests was a relatively small 0.04 (9%) on the flatground and the embankments (Fig. 3). This demonstrated
that it is possible to evaluate the performance of a railway
vehicle in resistance to overturning in windy conditions byusing a static train model in wind tunnel tests.

Wind（Natural wind）

Leading vehicle

Running velocity

Embankment modelFig. 2 Vehicle and infrastructure model

Annual Report 2017-2018

Side force coefficient

1.4
1.2
1.0
0.8
0.6
0.4
0.2

Static condition
Running conditions

0.0
20
30
40
50
60
70
80
90 100Wind angle relative to the train at the height of the carbody centre (degrees)Fig. 3 Comparison of side force coefficients on leading vehicle on embankment (1/60th scale model of commuter train)

31

Major Results of Research and Development

29.Wind tunnel tests for detailed detection of sources of
aerodynamic noise from bogies• A measuring method for detecting the sources of aerodynamic noise from bogies was developed
using a “sound transmission plate”• It was found that the main sources of aerodynamic noise were the traction motor and the gear unit.
• This method will now allow the reduction of the aerodynamic bogie noise more efficiently.
The main sources of aerodynamic noise from a railway vehicles running at high speed are the head car,pantographs and bogies. Work is ongoing using RTRI’slarge-scale low-noise wind tunnel facility to find ways toreduce aerodynamic noise generated by bogies, however,it has not been possible so far to clearly detect the exact
location of aerodynamic noise sources in a bogie throughlateral acoustic investigations because the bogie is fully
covered.
Therefore, the ground plate beneath the bogie was
replaced with a sound transmission board, which allows
sound waves to pass through but blocks air flow, and a
microphone array was installed beneath the board. The
proximity of the microphone array to the bogie made it possible to accurately distinguish the sources of aerodynamic
bogie noise (Fig. 1).

The results from tests using this method identified themain sources of aerodynamic bogie noise to be the traction
motor and the gear unit among others (Fig. 2). An acoustic
test using a speaker confirmed that the influence of thesound transmission board on measuring the location ofsound source was sufficiently small.
By using the developed measurement method, it will bepossible to locate various sources of aerodynamic noise,and contribute to the reduction of aerodynamic bogie noise.

Wind speed 325 km/h

Sound transmission board

Bogie equipment

Traction motor

Mounted during tests

Gear unit

Low
Microphone array

Fig. 1 Acoustic source investigation using sound

32

10dB

high

Bogie equipment seen from the bottom up
Fig. 2 Sources of aerodynamic bogie noise

Annual Report 2017-2018

Railway Technical Research Institute

30. Assessment of driver state based on physiologicalindices• It is now possible to objectively monitor changes in the physiological state of drivers as they carry out
their driving tasks, based on simultaneous measurement of various physiological indices using highperformance multipoint electroencephalographs etc.
• By combining various physiological indices, it is possible to detect moments of concentration or
psychological upset.
With a view to supporting drivers to prevent humanerror induced accidents, an experimental environment(physiological indices measurement system) was designed
incorporating various cutting edge measurement technologies, which makes it possible to measure variations in thephysiological state of drivers when carryout driving tasks.
The physiological indices measurement system combines high-resolution multipoint encephalographs withother simultaneously measured physiological factors suchas pupil diameter, electrocardiography, respiratory waves
and perspiration. In addition, the system also uses motion
capture and eye tracking technology which can then be applied to convert attention point data based on the subject’s
degree of movement in space, into digital form (Fig. 1).
A basic tests were conducted using the measurement
system on a normal adult as subject placed in a driving
simulator, which suggested that it is possible to pick upchanges in state of mind of the participant in abnormal
situations using the multiple physiological indices.
The experiments involved confronting the subject
with an accident scenario, or asking them to drive underpressure to meet tight timetabling requirements. Results
confirmed that concentration and decrease in alertness
during driving tasks, and the level of stress due to an

accident could be objectively evaluated based on brain
activity (Fig. 2).
Given the disparity in physiological indices obtained
from person to person, it has been difficult up until now to
use indices quantitatively. However, it has been suggested
that there appears to be a way to reproduce typical variation patterns based on a combination of certain common
indices found in individuals. Based on variation patternsof physiological indices found in certain individuals, thismethod should make it possible to objectively assesschanges in state of concentration or psychological upset.
Line of sight –pupil diameter

Brain waves

Perspiration

ECG
Respiration

Fig. 1 Physiological index measurement system and mock
driving experiment setup
Normal conditions

When fallen tree is discovered

Brain Alpha wave distribution two seconds before
and after discovery of the fallen tree on the track.

Pupil diameter Respiratory Heart rate Operation
waveformof brake
(mm)
(bpm)

Compared to pre-discovery, post-discovery distribution
shows an increase in deeper shade of blue in the prefrontal
area indicating greater brain activity.

10
5

Emergency brake

0100

When fallen tree
is discovered

80
60
0.1
0
-0.1
4
3
2
0

10

20
30
Time (seconds)

40

50

Fig. 2 Change in physiological indices in abnormal situation

Annual Report 2017-2018

33

Major Results of Research and Development

31.Multi-segment pantograph head with high complianceto contact wire fluctuation.
• A multi-segment pantograph head has been proposed which not only produces less noise but alsooffers high compliance to contact wire fluctuation .
• Compared to a conventional type pantograph head fitted with flexible contact strip support, tests
confirmed that the multi-segment panhead had ten times more compliance and a 50% lower contact
loss ratio.
Giving the cross-section of a pantograph head a curved
surface is an effective measure to reduce aerodynamic
noise. This type of conventional pantograph head howeverneeds to be fitted with a flexible contact strip support inorder to follow to the unevenness of the contact wire (thewhole contact strip moves vertically against the crosssection of the pantograph head). In doing so in this typeof pantograph head, the vertical movement of the contact
strip makes the lift force susceptible to change, which can
at high speeds induce unwanted vibration in the pantograph head.
For solving this problem a multi-segment pantographhead was proposed. In order to guarantee both low noiseand lift force stability, the shape of the pantograph headcross-section was made to be curved, and to be used
only in one travel direction. In addition, the pantographhead itself was divided into segments, so that each segment of the pantograph head was capable of verticalmovement whilst maintaining the same cross-section
shape, in order to follow to the contact wire. In orderto keep the weight of each moving part as low as possible, a carbon composite contact strip was adapted tothe multi-segment pantograph head and a prototype
was built (Fig. 1) and compared to a conventional type
pantograph head with flexible contact strip support for
current collection performance (Fig. 2). Compared to theconventional pantograph head, the compliance performance of the multi-segment pantograph head to contact
wire unevenness corresponding to the frequency bandof dropper intervals at a running speed of 300-400 km/h
was ten times higher (Fig. 3). In addition, it was confirmedthat the contact loss ratio was reduced by about 50% at arunning speed of 300km/h with a current of 400A (Fig. 4).
This prototype will contribute to further improving pantograph design.

Fig. 1 Prototype of multi-segment pantograph head and crosssection shape
Fig. 3 Compliance characteristics of multi-segment
pantograph head and conventional pantograph headFig. 2 Current collection performance verification
tests using pantograph testing equipment

34

Fig. 4 Comparison of contact loss ratio between multi-segment
pantograph head and conventional pantograph head

Annual Report 2017-2018

News
ReleaseRailway Technical Research Institute

1. RTRI Co-Hosts France-Japan Railway Technology
Symposium 2017
On April 23, RTRI co-hosted “France-Japan Railway Technology Symposium – Urban Railways of the
Near Future –“ with the Maison Franco-Japonaise. The main hosts of this symposium are la SociétéFranco-Japonaise des Techniques Industrielles (SFJTI) and French Embassy in Japan.

The first France-Japan Railway Technology Symposium
was held in 2007, followed by the second one in 2012 andthe third this year. This year’s symposium was organizedunder the theme ”Urban Railways of the Near Future”
and experts of Régie Autonome des Transports Parisiens(RATP), Alstom and Institut Français des Sciences etTechnologies des Transports de l’ Aménagement et desRéseaux (IFSTTAR).
RTRI has maintained a collaborative research agreement with IFSTTAR and co-hosted this symposium in orderto share information with French rail-related organizations
regarding state-of-the-art technologies such as autonomous driving, artificial intelligence and Internet of Things.
From Japan, engineers and researchers of East
Japan Railway Company, Tokyo Metro Co., Ltd., Bureauof Transportation of the Tokyo Metropolitan Government,
and RTRI participated. The following seven presentations were delivered by these French and Japanese andshared issues in both countries’ urban railway systems
were described and solutions toward the near future weresuggested. Representing RTRI, President Kumagai gave awelcome speech and Executive Director Watanabe madea presentation.
About 110 persons from Japan and other countries
joined this symposium and discussions were made regarding the current situation and issues of urban railways.

Details of the Symposium
1. Date and time: April 23, 2017 13:30 - 18:00
2. Venue: Maison Franco-Japonaise
3. Host organizations
Main hosts :La Société Franco-Japonaise des Techniques
Industrielles, Japan (SFJTI)Annual Report 2017-2018

French Embassy in Japan
Co-hosts : Maison Franco-Japonaise in Ebisu(MFJE)
Railway Technical Research Institute, Japan (RTRI)
Patronage:
Ministry of Land, Infrastructure, Transport andTourism, Japan (MLIT)
Régie Autonome des Transports Parisiens, France(RATP)
Tokyo Metro Co., Ltd.
Sponsors:
Japan Railway Engineers’ Association (JREA)
Japan Subway Association (JSA)
4. Program
Opening remark by Mr. Yutaka Takahashi, Presidentof SFJTI
Welcome by Mr. Yuki Yokoyama, Vice President, MFJE
Welcome by Mr. Norimichi Kumagai, President, RTRI
Greetings by:
Mr. Shunya Shiozaki, Deputy Director-General forEngineering Affairs, Railway Bureau, MLIT
Mr. Takao Nishiyama, Executive director, East Japan
Railway Company
Presentations(1) “Mobility Revolution by the East Japan Railway
Company with IoT and AI”
Mr. Atsushi Yokoyama
Executive Officer
Director, Technology Planning Department
Director General, Research and Development
Center of JR East Group
East Japan Railway Company(2) “Parisian Metro Network Modernization, Energy
Saving and Automation””
Mr. Jean-Marc Charoud, Director of the Engineering
Department, RATP
Mr. Claude Andlauer, Head of Railway Transportation
Systems, RATP

35

News Release36(3) “Railway Innovation Based on Network andSimulation”
Mr. Ikuo Watanabe, Executive Director, RTRI
(4) “Technological Development of Tokyo Metro”
Mr. Akihiro Kosaka, Director, Corporate Value
Enhancing Department, Tokyo Metro Co., Ltd.
(5) “Light Transit System in Tokyo Metropolitan Area”
Mr. Masaru Furuta, Former Bureau of Transportation,
Tokyo Metropolitan Government(6) “Alstom Business with Japanese Urban Transport”
Mr. Gérald Kowalski, Customer Director forInternational Business, Alstom(7) “R&D on Railway Infrastructures and Systems at
IFSTTAR”
Mr. Bruno Godart, Deputy Director of Materials
and Structures Department, Institut Français desSciences et Technologies des Transports de l’Aménagement et des Réseaux, France (IFSTTAR)

General review
Mr. Pierre Feuardant
Project Manager in Science and Technology, Embassyof France in Japan

President Kumagai of RTRI

Executive Director Watanabe

Closing remark
Mr. Tatsuhiko Suga, Chairman of the Railway
Transportation Committee
La Société Franco-Japonaise des Techniques
Industrielles (SFJTI)Annual Report 2017-2018

Railway Technical Research Institute

2. RTRI Sets up ICT Promotion TeamOn June 1, RTRI set up the ICT Promotion Team. The Team has been established in order to develop
a strategy and plan to promote systematic use of information and communication technologies in RTRI’s
entire research and development activities and to increase their speed.

This team, lead by Mr. Hiraguri, Deputy Director of the
Research and Development Promotion Division, consistsof principal researchers, directors and general managersof concerning research laboratories. President Kumagai,
Executive Director Ashiya and Mr. Furukawa, Director of
the Research and Development Promotion Division, havealso joined the team as supervisors. Under the team,three subgroups, sensing, information communications
and control, data analysis, have been set up.

Kumagai’s greetings, topics for research and developmentusing ICT have been listed. These are enhancing safety
and stability, autonomous driving and energy saving in
train operation and an advanced condition monitoring byautomated monitoring technologies. Techniques to shareand use data were also referred to at the meeting as important basic technologies. The members discussed what role
RTRI should play in order to develop these technologies.

On June 9, the first joint meeting of the team andsubgroups was held. At the meeting, following President
Fields and Topics to use ICTICT Promotion Team will propose a basic policy of
research and development using ICT. At the next phase,after September this year, the team will set ICT Innovation
Projects according to the proposal and establish a strategy
and an action plan for research and development. The
research and development will be promoted in cooperation
with other organizations which have advanced technologies, including universities.

extensive and intensive use of ICT. Since railway systems
are mainly based on conventional infrastructure, it is quite achallenge to apply innovative technologies to them, and justbecause of that, there is a possibility to be able to create arailway system surpassing current systems by using ICT.
So, I would like to set out a reliable strategy and would like
you all to actively implement research in order to build a
new railway system.

[ President Kumagai’s greetings ]RTRI has already been utilizing ICT in our research activities in specific technical fields and has been developing
the knowhow. But now, we need to focus our accumulated
knowhow on the newly-set research target which requires

Annual Report 2017-201837

News Release

Roles of ICT Promotion Team and ICT Innovation Projects

Members of ICT Promotion Team
Leader:•Deputy director of Research and Development
Promotion Division
Members:•Principal researchers of Research and Development
Promotion Division•Director of Power Supply Technology Division•Director of Track Technology Division•Director of Disaster Prevention Technology Division•Director of Signalling and Transport Information
Technology Division•General Manager of Transport Operation Systems•Director of Railway Dynamics Division•Director of Human Science Division•Manager of Research and Development Promotion
Division (secretariat)
Supervisors:•President•Executive director for research and development•Director of Research and Development Promotion
Division

The 1st meeting of the team and subgroups

38

Annual Report 2017-2018

Railway Technical Research Institute

3. The Vertical Vibration Reduction Control System Mounted
on the luxurious trains of JR East and JR West

The “vibration reduction control system using variable vertical damper,” what we call vertical vibration
reduction control system, jointly developed by Hitachi Automotive Systems, Ltd. and Railway TechnicalResearch Institute (RTRI) has been mounted to the luxurious trains newly launched by JR East and JR
West, “Train Suite Shiki-Shima”, and “Twilight Express Mizukaze.”

Fig Vertical vibration reduction control system mounted “Train Suite Shiki-Shima”
and “Twilight Express Mizukaze”

The vertical vibration reduction control system wasdeveloped to reduce vertical vibration of running railway
vehicles. This system has already been mounted on sightseeing express trains of JR Kyushu including “Ibusuki no
Tamatebako” and “Yufuin no Mori” and has contributed
to improving the ride comfort on these trains by reducing
vertical vibration by up to 50%. “Seven Stars in Kyushu,”a luxurious train of JR Kyushu which started operation in2013 has also been equipped with this system.
On May 1 and June 17 this year, luxurious trains of JR
East and West, “Train Suite Shiki-Shima” and “Twilight
Express Mizukaze” started commercial services. Following“Seven Stars in Kyushu,” this system has also been

Annual Report 2017-2018

mounted on these two trains. Now all the luxurious trains
in Japan have this system and their ride comfort is muchhigher than conventional passenger vehicles.
Overview of Vertical Vibration Reduction Control
System
In this system, variable vertical dampers (verticaldirection hydraulic dampers capable of controlling damping
force) and the secondary pneumatic suspensions aremounted on bogies in parallel. The dampers reduce verticalvibration by controlling the damping force so as to cancel
vibration of carbody based according to acceleration
measured by on-board (Fig. 1 and Fig. 2).

39

News Release

Fig.1 Structure of Vertical Vibration Reduction Control System

Fig.2 Variable vertical dampers mounted on vehicle, accelerometers and control unit

40

Annual Report 2017-2018

Railway Technical Research Institute

4. RTRI and Taiwan Railways Administration Co-Hosts
Technical Exchange Seminar
RTRI concluded an agreement for technical cooperation with TRA and the experts of both organizations
have been sharing information on railway technologies.

Participants from TRA and RTRI

On June 16 this year in Taipei, RTRI and TRA organizeda technical exchange seminar on railway technologies.
Seven people from RTRI including five experts and 70
people from TRA including four experts joined this seminar.
The participants exchanged information on the research and development of each organization regarding
the following four topics proposed by TRA:

The presentations were followed by lively Q & A sessions and discussions.

•The strategy of noise control for elevated railway system (ballasted and non-ballasted track) in metropolitan
area•Whole life cost analysis for rolling stock•Positioning technology analysis on shortage points foroverhead catenary system and early prediction method
for material variation of the overhead catenary system•The latest status of international standardization activities in railway field

Annual Report 2017-2018

41

News Release

Program of the 2017 TRA & RTRI Technical Exchange Seminar

42

Annual Report 2017-2018

Railway Technical Research Institute

Director General LU of TRA (right) and General Manager MIYAUCHI of RTRI (left)
exchanging gifts

Technical Exchange Seminar

Annual Report 2017-2018

43

News Release

5. RTRI Develops New Superconducting Power Cable System
for Testing on Commercial Railway Line
RTRI has developed a new superconducting feeder cable system which is closer to practical use, andis planning to test the system on an urban commercial line.

New superconducting feeder cable system at RTRI’s Hino Civil Engineering Testing Station【New Superconducting Feeder Cable System】
By improving its cryocooler mechanism, RTRI has succeeded in developing this new superconducting feeder
cable system that has stable enough performance to betested on commercial lines. The superconducting layer of
its cable is made of a material with high insulation performance in order to keep constant temperature inside thecable (Fig. 1), and the current terminal has a structure
which prevents heat conduction. Furthermore, a Braytoncycle-type cryocooler customized for the cable has been
adopted. Due to these improvements, the new system
has come a step closer to commercial application, withthe following features.

Fig. 1 Inside of Superconducting Feeder Cable

44

Annual Report 2017-2018

Railway Technical Research InstituteFig.2: Ampacity of the New System•The cable temperature can be set anywhere between
65 (-208℃), and 77K. Since the existing cable needs
to be cooled down to 77K, it has been impossible tomaintain superconducting state, when a cryocooler
goes down due to any trouble. But this new system iscapable of keeping the superconducting state for a few
days even if its cryocooler is down. It means that we will
be able to keep the superconducting state if we needto shut down the cryocooler for maintenance purpose.
•Due to the improvement on the cryocooler, this systemdoes not need an auxiliary cryocooler which requires
refilling of coolant.
•We have already tried 2-week continuous operation andconfirmed that the system works normally.
This new system has thicker layer of superconducting
material and its ampacity is 8,000 A or more for 408-meterlong cable. (Fig.2) This ampacity allows 2 or 3 trainsets
of 10 cars running at a time in the same block between
substations, a typical operation pattern on urban commuterlines.
We are planning to conduct power transmission tests
with this system on a commercial track.

【Existing superconducting feeder cable system】
In the superconducting feeder cable system, the cablemade of high-temperature superconducting material iscooled to extremely low temperatures which createssuperconducting state and transmit electricity with zero
electric resistance. This system requires a cooling systemusing -196℃(77K) liquid nitrogen as a coolant. We haveinstalled the existing system to RTRI’s test track andconducted running tests in order to seek the possibility ofapplying high-temperature superconducting material torailway systems. These running tests have been conductedwith a trainset of 2 to 3 cars for a few days. The existing
system has a sterling-type cryocooler and, in order tocontinue the running tests, it has been necessary to refill
the auxiliary cooling device with coolant and cryocooler
control by engineers has also been required. Therefore,
development of high-performance, reliable cryocooler
mechanism has been our top-priority issue in order to apply
the superconducting feeder cable system to commercial
operation.

•Part of this project has been supported by the subsidy
for railway technical development by the Ministry ofLand, Infrastructure, Transport and Tourism.
•Part of this project has been implemented as theProgram to Promote Strategic Innovation by the Japan
Science and Technology Agency.

Annual Report 2017-201845

News Release

6. S-Shaped-Sleeper Concrete-Bed Track with Resilient Pad- Cost Reduced and Construction Time Shortened -RTRI has developed S-shaped-sleeper concrete-bed track. This track is easier to construct and cheaper
than existing concrete-bed track.

S-shaped-sleeper concrete-bed track with resilient pad【Outline】
RTRI has developed s-shaped-sleeper concrete-bed
track with rubber pad in order to reduce the construction
cost of existing concrete-bed track. Major points of thisdevelopment are as follows. (Fig. 1)
1. This track supports lateral load with shear key on theside of the rail and therefore the width of the concrete
track bed is thinner and its material cost is lower thanexisting solid-bed track.
2. Since this track uses short-fiber-reinforced concreteand has a structure proper to unreinforced concrete
track bed, additional reinforcing bars except the displacement guide have become unnecessary.

Since the workload to construct this S-shaped-sleeper
track is smaller than that of D-shaped-sleeper track, itsconstruction periods can be shortened by more than 40%.
In addition, as its material cost can also be reduced , theconstruction cost of the concrete track bed and of the entire
track can be cut by 60 % and 20% respectively.
【Commercial application】
This S-shaped-sleeper track was already introduced
to commercial track of a rail operating company in theend of 2016. We will prepare a handbook for its designand construction in half a year, and will further promote
its practical use.

3. Its formwork placement and alignment has been madesimpler so that accurate shapes of concrete track bed
can be determined only by pressing the formwork to
the end of sleepers and shear keys.

46

Annual Report 2017-2018

Railway Technical Research Institute【Background of development】【Background of development】 Concrete-bed track with
Concrete-bed track with rubber pad is one of ballastlessrubber pad is one of ballastless tracks which supports
tracks which supports sleepers with elastic materials such
sleepers with elastic materials such as rubber pad placed
as rubber pad placed between track bed and sleepers.
between track bed and sleepers.

Fig.1 Newly-constructed concrete-bed track with s-shaped sleeper

Fig.2 Existing D-shaped-sleeper concrete bed track

Since this type of track reduces noise and vibration
generated by running trains, it has been used mainly on
elevated tracks in urban areas.
The D-shaped-sleeper concrete-bed track that RTRI
developed in 1998 has also been widely utilized on JR
and other private railway lines and the total length of the
D-shaped sleeper track has amounted to 60 km. But thecomplicated placement and precise alignment of reinforcing steel and formwork requires a lot of work whenconstructed. (Fig. 2) In order to reduce the construction
cost and to expand the use of concrete-bed track, RTRI
has developed the S-shaped-sleeper track which is easier
to construct.

Annual Report 2017-2018

We have conducted real-vehicle-weight loading tests
and non-linear FEM analysis in order to check its performance and confirmed that this track has sufficient strength
to bear train load. Through running tests with motor cars,
we have also confirmed that it has the same level of basic
performance as the D-shaped sleeper track.

47

News Release

7.Tunnel Crack Detection with Deep Learning
RTRI has developed a new technique to detect cracks on tunnel lining using deep learning technology.
This technique will enable more efficient tunnel maintenance.

【Outline】
With this technique, the cracks are automatically detected from the images of tunnel lining. (Fig. 1)
1.Using deep-learning technology, this technique iscapable of detecting cracks as accurately as visual
detections. (Fig. 1) With this technique, it is possible
to clearly distinguish cracks with other similarly-looking
objects such as signaling cables, contact wires andjoints and exclude these noises.

3.It is capable of detecting more than 83% of cracks
wider than 0.5 mm.
4.It is capable of checking the images covering 1 km
length of a tunnel in 15 minutes.
5.The images can be processed with a computer at
offices near tunnels.

2.It automatically processes, at one time, all the images of the entire tunnel lining surface taken by alaser-camera.

Fig.1 Cracks detected this technique

48

Annual Report 2017-2018

Railway Technical Research Institute【Detection using deep learning】
This technique has applied deep learning technology tocrack detection. It makes a computer to learn both images
with and without cracks so that the computer will be able torecognize cracks accurately. (Fig. 2 left) Then the computer

will examine the images of tunnel lining, detect cracks
and process the images to display the detected cracks
accurately. The results have succeeded in showing only
cracks without other similar objects such as cables andjoints. (Fig.2 right)

Fig. 2 Crack detection using deep learning technology【Existing image processing technology】
In order to correctly detect troubles on tunnel lining
surface such as cracks with existing image processing
programs, it has been necessary to adjust parameters
according to tunnel shapes and conditions of tunnel lining, using special know-how based upon experience. In
addition, it takes a lot of work to correct detection errors
caused by similar objects.
Deep learning is one of the analytical methods using
machine learning. Its neural network algorithm which has
imitated the human brain’s neural system has multiple
layers between the input and output layer in order to beable to solve complicated problems. We have made ourcomputer learn the images with and without cracks repeatedly with the deep learning method so that it will be able
to recognize the rules and patterns of the images, andto detect whether the tunnel lining has cracks or not as
accurately as humans do.
【Patent pending】

Annual Report 2017-201849

News Release

8. RTRI Launched Rail Maintenance & Welding Laboratory
On October 2, 2017, Rail Maintenance & Welding Laboratory was launched as a new laboratory in
the Track Technology Division of RTRI. This laboratory will take the responsibilities of research anddevelopment and technical support on rail maintenance, and it will quickly meet the needs of railway
operators.
RTRI has developed rail flaw detection technologies, rail
repair techniques, anti-corrosion measures and rail welding
techniques for continuous welded rail. The new laboratory
will actively utilize ICT including AI and develop highspeed, non-contact rail flaw detection technologies and50

techniques to detect broken rails without using track circuit.
This laboratory has also taken over the research work onrail welding from the former Rail Welding Laboratory.

Annual Report 2017-2018

Railway Technical Research Institute

9. RTRI and IFSTTAR Conclude Agreement on Collaborative
Research
On October 24 this year, the French Institute of Science and Technology for Transport, Development andNetworks (IFSTTAR) and RTRI signed an agreement on collaborative research in railway engineering.
1. The goal of the agreement
Both institutes concluded this agreement in order tocollaborate together in advanced and practical railway
research and in personnel exchange and training by utilizing their research resources. Their goal is to contribute todevelopment of railways, science and technology throughthis collaborative relationship.
2. The background of the research collaboration
In fiscal 2014 and 2015, RTRI implemented collaborative research and exchanged researchers with IFSTTAR,
and since then, both institutes have continued technicalexchange in design, construction and technical development of geotechnical engineering.
Since it is highly likely that the research collaborationand personnel exchange will be continued, RTRI andIFSTTAR concluded the agreement in order to strengthen
their collaborative relationship.
3. Form of collaboration and research topics
Under this agreement, IFSTTAR and RTRI will collaborate in the activities shown below.
(1) Collaborative research and information sharing projects with following three topics
・Analysis of scouring at river bridge base and soil
erosion・Comparison of Japanese and French technicalstandards for base and soil structures
・Information sharing on the methods to analyze
ground-structure dynamic interaction(2) Organizing joint research seminars(3) Personnel exchange – sending researchers to eachorganization
4. Messages from RTRI and IFSTTAR
Norimichi Kumagai, President of RTRI
I am honored to implement collaborative research withIFSTTAR, a prominent research institute on advanced
research and development in geotechnical engineering. In
recent years, the Japanese government has been leading
an effort to enhance the resilience of our national land.
But, over the last 6 years, Japan has been hit by many

Annual Report 2017-2018

natural disasters and suffered serious damage. We would
like to continue technical development to reinforce railway
systems, taking specifically defined steps.
Hélène Jacquot-Guimbal, Director General of IFSTTAR
Researchers of RTRI and IFSTTAR have had meetingsand shared their expertise at every phase,in particular,
on the topics of railway infrastructure and the risks ofearthquake and other natural disasters. Through thisprocess, we have forged a close relationship by the visits
of executives to each other and exchange of geotechnicalengineers. I am very much pleased that we have been
seeing each other very frequently in spite of the distance
between Japan and France. I hope to focus our efforts on
this 5-year collaborative research and to intensify various
fields of rail and transport research.
5. Signing ceremony
Date and time:October 24, 2017 14:00 – 15:00
Venue:IFSTTAR head office (Marne-la-vallée)Participants:
IFSTTAR
Ms. Hélène Jacquot-Guimbal
Director General
Dr. Éric Gaume
Head of Geotechnical Engineering, Environment,
Natural Hazards and Earth Sciences Department
Dr. Christophe ChevalierHead of Soils, Rocks and Geotechnical Structures
Laboratory
Geotechnical Engineering, Environment, Natural
Hazards and Earth Sciences Department
Dr. Jean-François Semblat
Deputy Head of Geotechnical Engineering
Head of Earthquakes and Vibrations Laboratory
Geotechnical Engineering, Environment, Natural
Hazards and Earth Sciences Department
Mr. Fabien Szymkiewicz
Soils, Rocks and Geotechnical Structures Laboratory
Geotechnical Engineering, Environment, Natural
Hazards and Earth Sciences Department
Mr. Bruno Godart

51

News Release

Head of Materials and Structure Department
Dr. Claude Marin-Lamellet
Deputy Head of European and International Affairs
Ms. Christelle Fongue
Manager of Bilateral and Multilateral Cooperation
Projects
RTRI
Norimichi Kumagai
President
Ikuo Watanabe
Executive Director
Atsushi Furukawa
Director
Research and Development Promotion Division
Naoyuki Ota
Director
Disaster Prevention Technology Division
Kenji Watanabe
Laboratory HeadFoundation and Geotechnical Engineering

Osamu Nunokawa
Laboratory Head
Geo-hazard and Risk Mitigation
Shuichi Myojo
Manager International Division
6. IFSTTAR
A national research institute of France, IFSTTAR, wasformed in 2011 by the merger of the French National
Institute for Transport and Safety Research (INRETS)
with the French Central Laboratory of Roads and Bridges(LCPC). Its head office is located in Marne-la-vallée and1,200 people works for IFSTTAR. Its research work covers
wide ranging fields including urban and civil engineering,natural disaster mitigation measures, transport efficiency
and safety. In particular, it has been promoting civil engineering research and development from basic to practicalon an impartial footing and has been involved in the work
to set French domestic standards and Euro Code.

President Kumagai and Director General Jacquot-Guimbal at signing ceremony

52

Annual Report 2017-2018

Railway Technical Research Institute

10.RTRI Launched Image Analysis and IT Laboratory
On December 1, 2017, Image Analysis and IT Laboratory was launched as a new laboratory in the
Signalling and Transport Information Technology Division of RTRI.
RTRI will promote the research and development
regarding information technologies, specifically, image
analysis technologies, big data analysis and deep learning, in order to meet the needs of railway operators more
quickly and to propose new technologies of these fields.
For these purposes, a new laboratory “Image Analysis
and IT” was set up in Signalling and Transport Information
Technology Division. RTRI will actively utilize imageprocessing technologies and IT that the researchers havealready accumulated and used in different technical fields.
This laboratory will seek to apply image analysis
technologies to constant condition-monitoring for railway
facilities and train driving safety and to use IT in maintenance and operation control.
At the inauguration of this laboratory RTRI’s president
Dr. Kumagai expressed his expectations for the new members, and Dr. Masato Ukai, the head of the laboratory, also
expressed his wishes.
President Kumagai’s statement
There are two purposes for the newly-established Image
Analysis and IT Laboratory. First one is to quickly andactively implement the research into IT for railways utilizing
the expertise of different fields of researchers. For thispurpose, the members of the new laboratory have beenchosen from among every research field at RTRI. In order

Annual Report 2017-2018

to introduce IT to railway operations, high-performancelow-cost systems need to be established. I hope thatthe researchers will integrate their research results andexpertise and that synergy will be generated. The second
purpose is to create a place where the researchers interested in image-related technologies and IT and hoping to
get involved will be able to have discussions openly andfreely and to absorb scientific knowledge. Every researchers active involvement is highly anticipated.
Greetings from Dr. Ukai, Laboratory Head of Image
Analysis and IT Laboratory
The Image Analysis and IT Laboratory is unique in that
researchers from different research fields have gathered
here. It is essential to make the best use of RTRI’s technical resources in order to generate effective results as earlyas possible. Now, its stage has been set. By sharing theexpertise of each researcher, I believe we will be able tohave synergy effects that is impossible without sharing andcooperation. We might have to start without a chart, but wewill keep close communication among the members anddedicate our efforts in order to create innovative results.
Image Analysis and IT Laboratory is launched with
Laboratory Head and 12 researchers.

53

News Release

President Kumagai (second left, front row) and the team of the new laboratory

54

Annual Report 2017-2018

Railway Technical Research Institute

11. RTRI and DLR conclude LoI and Collaboration Agreement
On March 1, 2018, at the German Embassy, Railway Technical Research Institute (RTRI) and the German
Aerospace Center (DLR), concluded a Letter of Intent to build a close relationship and a collaborationagreement on research in the field of large-scale 3D model experiments on micro-pressure waves .

1. The goal of the LoI and collaboration agreement
Under these LoI and agreement, RTRI and DLR will
explore possible scientific fields suitable for their collaborative research and information sharing and promotecollaborative projects utilizing the research resources andexpertise of both organizations. They concluded the agreement on 3D model experiments regarding micro-pressure
waves based on the LoI.
2. Background of the collaboration with DLR
RTRI and DLR have been sharing information on railway
technologies so far. In 1997, one of RTRI’s researchers
stayed at DLR and conducted collaborative research on
the measurement of aerodynamic noise at a wind tunnel.
Since both organizations have strongly recognized thenecessity to conduct collaborative research and personnel
exchange, they concluded the LoI to deepen their tie forthe future.
3. Main points of the LoI(1) To implement collaborative research(2) To hold management meetings in order to further
strengthen the RTRI-DLR relationship(3) To share views for the future research collaboration
4. Greetings by President of RTRI and Chair of DLR
Dr. Norimichi Kumagai, President of RTRI
Thank you so much for setting today’s signing ceremony.
I am so pleased that so many people are attending thisceremony, in particular, Dr. Wolfgang Sheremet, DirectorGeneral of Industrial Policy Bureau of the Federal Ministry
for Economic Affairs and Energy.
It is great honor for me to conclude the collaborative research agreement with DLR, the most influential
research institute in Germany which has abundant expertise and resources. It was also my pleasure to meet Prof.
Pascale Ehrenfreund yesterday, and to have a significant
discussion in order to build the RTRI-DLR collaborative
relationship. First, RTRI and DLR will start a collaborative

Annual Report 2017-2018

project related to aerodynamic issues for railway vehicles,
and continue to strengthen our relationship in other fields
of scientific research.
Prof. Dr. Pascale Ehrenfreund, Chair of Executive Boardof DLR
It is a great honor for DLR to conclude the agreement
for collaborative research with RTRI. I am so pleased to
be able to intensify cooperation with our Japanese partner,
RTRI, in the field of transport. With this agreement, we will
start collaborative research in the field of aerodynamics,
and I am also very happy that our researchers have alreadybeen cooperating since quite some time. Yesterday, we
visited RTRI, joined a very interesting tour to test facilities
and had a really great discussion. I would like add thisagreement is very much supported by the Federal Ministry
for Economic Affairs and Energy.
5. Signing ceremony
Date and time: March 1, 2018 18:30 – 19:00
Venue: German Embassy in Japan
Participants:
RTRI
Dr. Norimichi Kumagai President
Dr. Ikuo Watanabe Executive Director
Dr. Kimitoshi Ashiya Executive Director
Mr. Ryuji Tsuchya Director, International Division
Dr. Atsushi Furukawa Director, Research andDevelopment Promotion Division
Dr. Kiyoshi Nagakura Director, Environmental
Engineering Division

German side
Dr. Wolfgang Scheremet Director-General Industrial
Policy Bureau of the Federal Ministry for Economic
Affairs and Energy, Germany
Prof. Dr. Pascale Ehrenfreund Chair of Executive Board

55

News Releaseof DLR
Mr. Siegfried Loose Institute of Aerodynamics and Flow
Technology, DLR
Mr. Nicolas Peter Director International Relations, DLR
Dr. Niklas Reinke Director Tokyo Office DLR
6. Overview of DLR
DLR, headquartered in Cologne, is a national agency of
the Federal Republic of Germany responsible for development of aeronautical technology and space research. It has
approximately 8000 employees and 40 research institutes,
and it has been implementing a broad range of research

Prof. Dr. Ehrenfreund, and Dr. Kumagai at the signingceremony56

and development covering aeronautics, space, energy,
land and ocean transport.
The Institute of Aerodynamics and Flow Technologyof DLR, the counterpart institute for the collaborative
research, is located in Goettingen and Braunschweig in
Niedersachsen and has been dedicated to the research
into tunnel micro-pressure wave, aeronautical dynamics,
dynamics of helicopters, aerodynamic noise, supersonictechnologies and other relevant fields.

Dr. Scheremet Prof. Dr. Ehrenfreund Dr. Kumagai

Annual Report 2017-2018

Master PlanRESEARCH 2020

Railway Technical Research Institute1 Basic policies

To contribute to the advancement of railways
and help bring about an affluent society, RTRI
actively promotes R&D activities geared towards
railway innovation, delivering high-quality results
by fully deploying its comprehensive capabilities.
In addition, to fulfil its social responsibilities asa public interest incorporated foundation, RTRI
is active in promoting engineering and legal
compliance and carrying out neutral activities,
such as providing technical support in the eventof a disaster or an accident, based on technicalknowledge and experience. Moreover, in order tobe the leader in global railway technologies, RTRI
helps with the effective deployment of Japanese
railway technology in foreign countries, simultaneously increasing its presence in the global market.
To achieve these goals, RTRI adopts the following basic policies:(1) Dynamic R&D to encourage railway
innovation

RTRI should respond to the changing times
and the various needs of society and carry out
innovative technical development as a matter ofurgency. It should strongly promote advanced
R&D and R&D in new fields, including enhancement of simulation technology and active use of
information and communications technology, by
allocating more resources to such activities. Also,
it should steadily pursue basic research that canbe a source of innovative technology.

(2) Achieving high-quality results by fully
demonstrating its comprehensive
capabilities

RTRI should rigorously accumulate know-how
and pursue the development of human resourcesin preparation for solving various problems in
the railway industry and developing innovativetechnology, and at the same time combine
the strength of researchers and experts in different fields. Together with these actions, theAnnual Report 2017-2018

organization’s original facilities and equipment
for research should be rebuilt or revamped.
Building on these measures, RTRI should
achieve high-quality results and disseminate themwidely around the world.

(3) Trusted activities based on technicalknowledge and experience

RTRI should accumulate deep insights acrossthe railway industry and carry out investigations
into the causes of accidents and the damage
caused by disasters, presenting methods to guard
against their reoccurrence, and formulating technical standards based on its technical knowledge
and experience as an independent third-party
specialist organization.

(4) Support for overseas deployment
and enhancement of the Japanesepresence in the international railway
sectorTo become a leader in the field of railway
technologies, RTRI should effectively support
the overseas deployment of Japanese railway
technology and simultaneously enhance its
global presence by disseminating information andbuilding close relationships with foreign railway
operators and research institutes. It should also
actively propose the adoption of international
standards from Japan.

(5) Ensuring that the working environment
allows all employees to be highly
motivated

RTRI should foster an environment where freeminded researchers and experts can perform totheir full potential and produce results that willbring a sense of accomplishment. It should also
promote a pleasant workplace culture that allows
unfettered discussions while respecting diversity
in terms of age, sex, culture differences and otherconsiderations.

57

Master Plan RESEARCH 2020

2 Business Activities(1) Research and development(a) Basic principles of R&D

RTRI pursues the improvement of safety
by developing better measures to prevent or
mitigate the effects of major natural disasters andimplementing derailment prevention measures.
It also seeks to reduce the cost of maintenanceand other elements of the rail business, to attainharmony with the environment by using energy
more efficiently, and to enhance the convenienceof rail travel thanks to further increases in train
speeds. Drawing on these activities, RTRI will
create innovative technologies that can contributeto railway advancement while solving various
problems confronting the railway industry today.
These challenges constitute the four “R&D
Objectives” that RTRI should follow.

R&D Objectives• Improvement of safety• Cost reduction• Harmony with the environment• Improvement of travelling convenience
In order to promote R&D, resources should
be augmented in leading-edge technical fields
such as advanced simulation and informationand communication technologies, as well as in
specific technical fields relating to safety, energy,
and faster running, and in other new areas.
In addition, in order to deliver high-quality results, original facilities and equipment for researchand testing should be enhanced; studies should
be carried out across various specific areas; accumulated know-how and data should be actively
used; and the ability to offer a comprehensive
service should be leveraged through networks
with railway operators and domestic and overseas
universities and research organizations.
Furthermore, aiming at reaching a balanced
distribution of resources and achieving effective
R&D, the following three agendas are adopted as
the “Pillars of R&D” (Figure 2-1-1).

58

Pillars of R&D• R&D toward the future of railways• Development of practical technologies• Basic research for railways(b) Research and development toward thefuture of railways

With the objective in mind of achieving practical applications in 10 to 20 years’ time, research
topics should be carefully selected according to
the following principles:○ Respond to the needs of the JR companies
and other railway operators, and respond tosocial trends○ Point to advanced R&D and the future ofrailways○ Leverage RTRI’s expertise in fields and areas
where RTRI has higher R&D capability andunique features○ Pave the way for practical R&D and solve
critical problems in practical R&D, and encourage research staff to make academic
contributions.
○ Pursue challenges that will have a large spinoff effect when put to practical use
In FY2015, RTRI will start to implement thefour major challenges: “Pursuit of Safer Railway
Systems,” “Revolutionizing Railway Systems
with Information Networks,” “Speed-up of the
Shinkansen,” and “Construction of Railway
Simulators.” In each major challenge, two or three
individual R&D projects have been set. Withineach of these there are two or more detailed R&D
projects. There will be links between the individual
R&D projects so that they are implemented in a
logical and systematic way (Figure 2-1-2).

(c) Development of practical technologies

Research issues affecting the railway businessthat will yield rapid results should be tackled so
as to achieve a practical outcome in a timely andsatisfactory way.
(i) R&D designated by JR companies
R&D that can contribute to the on-site solutionof problems should be carried out, in response
to various requests from JR companies and forwhich they have specific requirements. In R&D,

Annual Report 2017-2018

Railway Technical Research Institute

Figure 2-1-1
sufficient resources should be mobilized so as
to meet the needs of the railway business and toensure that results are provided promptly.
(ii) R&D initiated by RTRI to investigate technology for practical use
R&D into novel technology should be pursued,
taking fully into account the needs of railway
operators, leveraging RTRI’s specialist facilities
and analysis technology, and aiming at practicalapplication in actual fields of the railway business.
In addition, for dealing with issues that require
an immediate response, such as accidents ordisasters, an organization should be formed to
manage two or more issues so that it has an
overview of the situation, and solutions should
be proposed quickly.
(iii) R&D commissioned by the Government or
the public sector
R&D commissioned by the Government or the
public sector should be undertaken in order to put
results to practical use and make them widely
available.

Annual Report 2017-2018(d) Basic research for railways

In order to solve various railway problems
and address challenges related to sources ofinnovative technologies, basic research forrailways should have high-level backing and support. It should include the following objectives:clarification of mechanisms and phenomena;
establishment of analytical, experimental, andevaluation methods; development of sophisticatedsimulation technology; and the development of
new technologies, new materials and of different
approaches to research.
In the process of promoting research, thefollowing five items should be allocated higher
priority, while research in new areas such as brain
science is pursued.
- Prediction, detection, and prevention of phenomena that cause disasters- Clarification of dynamic phenomena causedby rail travel- Elucidation of deterioration/damage
mechanisms- Improvement of the environment along railway

59

Master Plan RESEARCH 2020

Figure 2-1-2

lines and the global environment- Improvement of safety with a focus on humanfactors(e) Facilities and equipment for researchand testing

Original facilities and equipment for researchshould be replaced where necessary; the selected facilities should be directly connected to
R&D activities in fields where RTRI intends tointroduce innovative technologies. In addition,
where the performance of test facilities has
declined over time so that they no longer meetR&D needs, they should be improved or renewed,
in addition to construction of new buildings forexperiments.

(2) Investigation of railway technologies
and science
RTRI should grasp social, economic and technological changes, and then collect and analyze
various types of information generated in Japanand foreign countries that is needed in order to60

contribute to the technical development of therailway business. Once this has been completed,
the results of such activities should be transmitted to the parties concerned. RTRI should also
predict the future status of railways and conduct
investigations necessary to choose technical issues for its R&D objectives.

(3) Preparation of drafts of railway
technology standards

In accordance with the rising importance ofthe management and maintenance of society’s
infrastructure and the Japanese Government’s
movement towards performance specification oftechnology standards, RTRI should promote theformulation and arrangement of design standards,
maintenance management standards, and design
calculation examples of infrastructure. Technicalfields, such as vehicles, where new technicalstandards should be formulated, and therefore
where systematization is needed, should be clarified. This should ensure that tasks such as theformulation of design standards in these fields
can proceed smoothly.

Annual Report 2017-2018

Railway Technical Research Institute(4) Collection and release of railwayrelated documents, materials andstatistics

RTRI should collect and collate information
on Japanese and foreign railway technologies. It
should also leverage various channels, such as
mass media and the Internet, and transmit R&D
results and activity status in a planned and timely
manner. It should play a role as a source to send
timely and precise railway technical information
to the public.

(5) Publications and lectures to raise theprofile of railway technologies andscience

RTRI should expand the contents of its periodicals, such as the RTRI Report and RRR, lecture
presentations, and technical forums. Throughthese instruments, the results of RTRI’s R&D
work should be offered widely to the public. The
courses of lectures on railway technology andother lecture presentations should be systematic,
and designed to meet the needs of all, from beginners to experts.

(6) Diagnosis, advice and guidance on
railway technologies and science

RTRI should respond precisely to requests
from railway operators to continuously and positively carry out its mission. Especially in offeringa consulting service in response to a disaster oran equipment failure, a quick response shouldbe agreed in a tie-up with the railway businesses
or operators involved. Furthermore, consulting
services for local railway companies should beenhanced by making site visits and giving technical advice.

(7) Drafting of original plans andproposals for standardization withregard to international railway
standards
RTRI should promote, in a strategic way, activities related to the International ElectrotechnicalCommission (IEC) and the International
Organization for Standardization (ISO). In particular, RTRI should actively participate in theoperation of TC 269 (Railway Applications),
newly established in ISO in April 2012. It should

Annual Report 2017-2018

also strengthen its resources, and press on withprojects such as “rail project planning” which
Japan proposes. At the same time, RTRI should
exercise leadership in standardization activities in
the fields of operations and services where Japan
has technical predominance.

(8) Authorization of qualifications withrespect to railway-related science andtechnology

With a focus on accreditation tests forProfessional Railway Design Engineers, RTRI
should build up and arrange improvements in
examination opportunities for applicants throughoverall verification of the tests, thereby contributing to the enhancement and maintenance of thelevel of technical expertise of railway engineers.

(9) Railway Technology Promotion
Center

RTRI should contribute to an improvement in
the level of technical expertise in the railway industry by promoting related business while taking,as pillars, systematization of technologies andproblem solving, enhancement and maintenanceof technical capabilities, and technical information services. For this purpose, it should tackle
new research and study topics that are usefulfor systematization of vehicle technology, andsimultaneously offer technical support to local
railways and encourage technology succession
by positively applying the knowledge of “RailAdvisers.” In addition, the contents of the safety
database should be enriched through intensified
research and analysis activities in the humanfactors field.

(10) Railway International Standards
Center

RTRI should promote strategic activities aimed
at introducing Japanese technical specifications and concepts into international standards.
It should actively exchange information with
European and Asian standardization bodies andintensify its partnerships with them, and also boost
educational activities on international standards
for the parties concerned and human resource
development activities.

61

Master Plan RESEARCH 2020(11) International activities

For the purpose of further improving thetechnical capabilities and presence of RTRI,
joint research programmes with foreign universities and research bodies should be expanded.
Exchange of researchers should be promoted
by sending more RTRI researchers abroad andreceiving more foreign experts in Japan. RTRI
should actively take part in the World Congress
on Railway Research (WCRR) as a member of
the Organizing Committee, going ahead withpreparation and management of the WCRR meeting to be held in Tokyo in 2019. RTRI should also
aspire to organize international workshops andjoin various types of international conferences
to exchange information on the latest railway
technologies. RTRI researchers should be sent
overseas to investigate global railway conditions
and technologies.
RTRI should contribute to the wider applicationof Japanese railway technologies across the world
by providing active support for railway operatorsand related businesses, assisting overseas
deployment of intellectual property, and offering
guidance to engineers in foreign countries.

62

Annual Report 2017-2018

Railway Technical Research Institute

YEAR 2017-2018: April 1, 2017 - March 31, 2018
Copyright© 2018 Railway Technical Research Institute.
All rights reserved.
Published by Kimitoshi ASHIYA, 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
Other Publications: http://www.rtri.or.jp/eng/publish/

Annual Report 2017-2018

63