ANNUALREPORT

2015-2016
For the year ended March 31, 2016

Railway Technical Research InstituteForeword
Norimichi KUMAGAI
President of the Railway Technical Research Institute
In FY2015, to fulfil the responsibilities placed
upon us by the railway industry and by society
in general, RTRI set out its vision for the future
entitled “RISING: We will develop innovativetechnologies to enhance the rail mode so that
railways can contribute to the creation of a happier society”.This vision includes three missions– “dynamic research and development”,“neutral
activities based on technological common sense”
and “world leading activities in technology”.A
business strategy, supported by a strengthened
management policy, has been devised to accomplish these objectives.
Specific measures for implementing the strategies were set out in a five-year Master Plan
drawn up by RTRI entitled “RESEARCH 2020
– Aiming at Creation of Innovative Technologies”.
Starting in FY2015, the Master Plan sets out fivebasic policies: “Implementation of intensified
research and development aimed at innovation
for railways”,“Creation of high-quality research
results with excellence across all fields ofactivity”,“Activities based on the best scienceavailable conducted in an ethical way”,“Supporting
overseas deployment of Japanese railway systems and enhancing our global presence” and“Achieving a working environment in which all
employees can be highly motivated”.Under the
Master Plan, RTRI is endeavouring to improvesafety by implementing significant measures toprevent or mitigate the effects of major natural
disasters, including derailment prevention measures. The Master Plan also seeks to determine
ways of reducing the cost of maintenance andother factors, as well as aiming for harmony withthe environment by more efficient use of energy
and making travel more convenient thanks to afurther increase in train speeds.

Annual Report 2015-2016

Based on these efforts, RTRI will develop innovative technologies that can contribute to railway
advancement while solving various problems that
confront the railway industry today. These challenges
constitute the four R&D Objectives of the Master
Plan. In addition, the Master Plan is built on three
R&D Pillars:“Research and development for the futureof railways”, under which four major topics will
be addressed for practical application in 10 to 20
years’ time: further improvements in the safety ofrailway systems, modernisation of railway systems
using information and communication technologies,
acceleration of services on the Shinkansen, andenhancing the role of railway simulators;“Development of practical technologies”, aprogramme designed to offer solutions that deliver
rapid results when dealing with problems affecting
the railway business; and“Basic researches for railways” which aims tosolve various railway problems and address challenges related to sources of innovative technologies.
In FY2015, the first year of the RESEARCH 2020
Master Plan, we strove hard to produce high-quality
results for dissemination across Japan and overseas,
pursuing R&D activities in line with the business plans
based on the Master Plan’s basic policies as well asworking on innovative test facilities such as highspeed pantograph testing equipment and low-noisemodel train running test equipment.
I am confident that we can enhance RTRI’s reputation and achieve greater recognition of the valueof its services by earning trust through high-quality
results. We will not only tackle the challenges ofsafety, energy, and greater speed, but also invest
our limited research resources in an effective
way, thereby creating benefits that will rapidly andaccurately meet the needs of railway companies. In
order to achieve this goal, guidance and advice fromall railway stakeholders are most appreciated.

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Overview

Contents

Organization

2 Overview
4

Major Results of
Research and Development

Board of Trustees

Board of Directors

Auditors

from
34 Results
individual R&D divisions

60 Outline of Activities FY 2015

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Railway Technical Research InstituteExecutive
Vice
Presidents

ChairmanPlanning Division

Vehicle Structure
Technology Division

Compliance Division

Vehicle Control
Technology Division

President
Executive
Directors

Administration Division
Miyazaki Test
Center

Structures
Technology Division
Power Supply
Technology Division

Accounting Division

Track
Technology Division

Information
Management Division

Disaster Prevention
Technology Division

Health Insurance
Systems Center

Signalling &Transport Information
Technology DivisionInternational DivisionInternational
affairs
International
Divelopment
Research &Development
Promotion Division
Wind Tunnel
Technical Center
Marketing & Business
Development Division
Railway Technology
Promotion Center
Railway International
Standards Center

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 July 1, 2016)

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Major Results of
Research and Development
This publication is a collection of the major results obtained from research undertaken by theJapanese public body, the Railway Technology Research Institute, in 2015.
We would like to take this opportunity to thank all JR companies in particular and all the research
centers, universities, industrial partners and other entities which have offered their cooperation,commitment and support to achieve these results and without whom none of this work would havebeen possible.

IMPROVEMENT OF SAFETY
1. Advanced seismograph for earthquake early warnings• A seismograph was developed to issue earthquake early warnings, offering more accurate seismicparameter estimation and timing, and improved noise discrimination functions.
• The new advanced seismograph makes it possible to cut the time between warnings being issued tothe arrival of seismic motion, by one second.
• Noise discrimination was improved by 7.4% compared to existing devices.

4

In order to increase the resilience of railways to natural
disasters, a seismograph which uses a single-station wasdeveloped for issuing earthquake early warnings with moreaccurate seismic parameter estimation and timing, andimproved noise discrimination functions.
Algorithms for earthquake detection and estimating epicentral distance, back-azimuth and magnitude were revised
to improve the estimation accuracy and timing. Resultsfrom simulations using post-earthquake data confirmed
better estimation accuracy. Using the improved algorithms,
the time from earthquake to warning can be reduced fromtwo seconds to one second. In order to distinguish between
seismic motion and train-induced vibration, a method wasdeveloped taking into account frequency characteristics
in addition to amplitude characteristics. Results fromsimulations applying this new method confirmed that noise
discrimination performance was improved by 7.4%. On-site
tests focusing on the performance of the newly developed
seismograph to distinguish between seismic motion andtrain-induced vibrations demonstrated that train vibration
was correctly recognised as being noise in over 99.9% ofcases (Fig.2). Practical tests with the seismograph also
confirmed their stable operation over long periods of time.
Given that these seismographs offer the opportunity toincrease the accuracy and reliability of earthquake early
warnings, it is planned to introduce these devices into
service. The objective now is to work with seismographmanufacturers to produce the device commercially by theend of 2016.

fig.1 Picture of prototype advanced seismographfor earthquake early warnings

fig.2 Results from practical tests
showing noise discrimination

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Railway Technical Research Institute

2. Method for extracting vulnerable structures during
earthquakes• A method for identifying vulnerable structures on long-distance lines has been proposed, where therunning safety of trains can be compromised.
• This method does not require large scale measurements or surveys and can be used with simple data
found in design documents, drawings and specifications.
• In cases of tall structures on stiff ground, it was possible to improve accuracy of estimated dampingby over 50%.
• The proposed method indicates the supplemental damping required to assure the running safety of
trains.
In order to understand the damping characteristics ofstructures for which little observation data is available,
vibration measurements were carried out on 136 actual
structures. An estimation formula was derived from observed data as a function of the natural period ratio of thestructure to the ground (Fig.1). In the case of tall structures
built on stiff ground (Fig.2), whose damping ratio waspractically assumed to be 5% in the seismic design standard, the accuracy of estimated damping was increased
by approximately 50%. In addition, a simple nomograph
was proposed to estimate whether a given structure was
likely to vibrate significantly or not, due to poor damping (Fig.3). This figure was composed on the basis of

response analyses, assuming various structural andground conditions while using actual damping measurements (Fig.1). The key feature of this method is that it
requires data which is easily obtained from design documents and drawings such as height of structure and groundcondition, which means that large scale measurements or
surveys are not necessary.
A nomograph was also been proposed for estimating
the supplemental damping needed for a structure tomeet requirements in the “Design Standards for Railway
Structures: Displacement Limits” (Fig.4). This nomographcan be employed in the seismic retrofit design of structureswith poor damping performance.

Fig.1 Nomograph estimating the damping performancebased on actual measurements

Fig.2 Example of small damping structure

Fig.3 Evaluation nomograph of actual structural response
as a ratio to structural response with damping of 5%

Fig.4 Nomograph showing damping needed to meet train
running safety requirements

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Major Results of Research and Development

3. Seismic reinforcement technology for earth retaining walls innarrow locations• A technique has been developed to adapt natural ground seismic reinforcement measures to steeper
and narrower locations• Confirmation was obtained that the present reinforcement method doubles seismic resistance• A design manual was produced containing all the methods for selecting which kind of seismic
reinforcement measure to apply to earth retaining walls

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There are over 200 000 earth retaining walls acrossJapan that were built according to the standard designused by the former national railways. The preponderant
seismic reinforcement measure to prevent collapse during
large earthquakes, involves pouring natural ground reinforcement material on near-horizontal planes to increase
the safety of the earth retaining walls. However, in cities
in particular, the crown of the retaining wall is often close
to buildings. Given the lack of space, it is difficult to pourreinforcement material along the full length required, whichmeans that even in places which desperately need seismic
reinforcement, it is impossible to apply existing remedies.
As such a new technique was developed (Fig.1) using
smaller sized equipment suited to narrower locations
and capable of pouring reinforcement material at steeper

angles and along the full required length. Results fromtests on a 1/10 scale model showed that a wall without thisseismic reinforcement collapsed under vibrations at 400
gal, whereas as the wall which had been reinforced using
this technique resisted to 800 gal vibrations, with horizontal
displacement stopping at 4%. These results demonstratethat the new technique offers greater seismic resistancethan existing methods, and confirm that seismic resistanceis doubled when the method is applied. In addition to
proposing a design method taking into account the flexural
resistance of reinforcement material poured on steep gradients, a design manual was produced containing all themethods for selecting which kind of seismic reinforcement
measure to apply to earth retaining walls.

Fig.1 Comparison of existing methods and the newtechniqueFig.2 Comparison of residual horizontal displacement after
each vibration excitation test.

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Railway Technical Research Institute

4.Method for assessing tsunami damage to concrete bridges• A method has been proposed to calculate the fluid forces acting on concrete bridges, from tsunamis• A method has been proposed to assess tsunami damage to bridge piers and concrete girder outflow• The assessment and calculation methods can be used to design girder outflow prevention work andbridge pier reinforcement against tsunamis.
In order to counter the impact of large scale tsunamis
caused by subduction-zone earthquakes, and to understand the damage caused by tsunamis to railway bridges,
methods were proposed to diagnose damage and to
calculate the effect of fluid forces acting on bridges.
In the course of this research, tsunami tests were conducted, providing insight into the fact that in the area close
to concrete bridge girders, the water level rose as the flow
speed fell, and that there was a difference in water levels
between the upper and lower flow around the girders (Fig.
1); a method was then proposed to calculate fluid forces
acting on girders.
The proposed methods can calculate fluid forces exerted on the bearing surfaces between concrete girders
and bridge piers, using information about the bridge, andthe height and speed of the assumed tsunami (Fig. 2). The
lower resistance forces of the bridge pier and the bearing(girder-dropping prevention devices) are taken to be bridge
resistance, which in turn is compared to the calculated
fluid force, in order to evaluate tsunami damage to theconcrete bridge in terms of girder outflow and damage topiers. Tsunami tests were carried out on a concrete bridgemock-up equipped with girder-dropping prevention devices
and steel bearings. The proposed method calculated thefluid force using the wave height and speed under which
bridge damage occurred, which corresponded more orless with bridge resistance, confirming that it was possible
to estimate the damage to the bridge (girder outflow, piercollapse) using tsunami data (Fig. 3). Estimating damage
prior to an event will facilitate the preparation of recovery
plans, and is also useful for developing the girder-outflow
prevention devices and bridge column reinforcements
against tsunamis.

Fig.2 Modelisation of fluid forces acting on bridge

Fig.1 Tsunami engulfing girder and increase in flow speed

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Fig.3 Results of bridge damage assessment

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Major Results of Research and Development

5. Management of snowmelt for landslide prevention• This method can be used to predict critical periods during the snowmelt season, using meteorological
data to estimate run-off volume from snowmelt to evaluate the safety of slopes.
• A surveying method is proposed using topographical and ground condition data to identify vulnerable
landslide prone locations.

8

On slopes adjacent to railway lines covered with thicksnow, runoff from melting snow seeps into the ground andcan sometimes cause landslides. Current operating rules
only have provisions based on rainfall volumes and do
not offer a means to predict critical periods or locations
vulnerable to landslide disasters, which is a problem. As
such, a safety evaluation method has been developed
based on the volume of runoff from snow, which is the maincause of landslides during the snowmelt period, along witha survey method which then identifies vulnerable locations.
There is a close correlation between slopes becoming
unstable and water saturation of the ground. Consequently,
using temperature and other meteorological data fromthe met office, a model was designed to estimate theamount of runoff seeping into the ground from melting
snow. The volume of runoff from melting snow is converted
into a suitable indicator to show water saturation of theground (hereafter “effective snowmelt volume”) and when
this effective snowmelt volume indicator exceeds a set
alert threshold, this means that the slope in question hasreached critical instability. Fig. 1 shows a typical example
of slope inspection using this method. The alert thresholdvalue is set according to maximum snowmelt runoff volumes based on past data.

Data from previous landslides was then collected to
identify which ground conditions made a slope particularly
vulnerable to this kind of disaster. Following this, a survey
was conducted of the ground conditions where landslides
have occurred in the past. Then, using topographical conditions and ground conditions, a method was developed toquantitatively assess the safety of slopes. By applying
these processes, it should be possible to identify criticallyvulnerable landslide prone spots during snow melting
periods (Fig. 2).

Fig.1 An example of an inspection of an earth-bank slopein critical condition.

Fig.2 Example of excavation of a critical area
on a slope after applying the survey procedure.

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Railway Technical Research Institute

6. Calculation of the aerodynamic coefficient on trains in halfbank half-cut line sections• A quantitative evaluation was made of the aerodynamic coefficient of trains on half-bank half-cut
sections of line
• For winds acting at an angle of 90 degrees on intermediate carriages, it was observed that runningsafety was higher with cut banks of a height of 10 m or half-bank half-cut embankments of 15 m.
• A proposal was made to use the aerodynamic coefficient as an indicator for evaluating safety in highwinds on sections with half-bank half-cut embankments.
Evaluation of running safety in high winds is carriedout using an aerodynamic coefficient obtained from windtunnel tests. There are many types of section topography
along actual railway lines, however, the aerodynamic coefficient is sought for seven standard types of track-side
structure. Many lines close to the coast or rivers are often
on tracks flanked by a slope on one side and a bank on
the other (half-bank half-cut sections), and are treated asembankments. However, on sections with high embankments on the downwind side, the lateral force acting on the
train is lower than on normal embankments, which meansthat the aerodynamic coefficient is probably smaller.
Therefore, wind-tunnel tests were conducted to obtain
the aerodynamic coefficient on a half-bank half-cut section.

During the wind-tunnel tests, the angle and height of the
cut slope was varied along with the distance between the
cut slope and the train center (Fig.1).
Results showed that in cases where the cut slope was
10 m or 15 m, as the distance grew shorter between theside of the train and flanking cut slope, and as the angleof the slope became steeper, the lateral forces acting on
the intermediate carriages of the train at 90 degrees fell
between 5-100% (Fig. 2).
The outcome of these experiments shows that safety
evaluation of half-bank half-cut sections can be carried out
more suitably than simply applying the standard embankment evaluation method used previously.

Fig.1 Wind-tunnel experiment and parameters for tests on a (actual scale) half-bank half-cut section(Reduced scale: 1/60, Train: roof curvature radius of 5000 mm (actual scale) of a commuter train)

Fig.2 Comparison between aerodynamic coefficients on a half-bank half-cut section and a normal embankment(intermediate carriages, wind angle 90 degrees, top of cut slope and distance to slope of 20m)

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Major Results of Research and Development

7. Revision of evaluation criteria to check deterioration in lubricating grease used on trains• The values used in criteria applied for managing the grease used in axle boxes and traction motors
have been revised.
• Lithium complex soap grease is used for lubricating traction motors on approximately 80% of conventionalline trains. A new indicator has been proposed for the thermal tolerance of this grease to replace‘changes in dropping point value’.
• New criteria values have been proposed as the new standard for evaluating deterioration in the grease.
Lubricating grease is critical for bearings to function normally on conventional and high speed trains (Fig. 1). It istherefore necessary to be able to diagnose accurately any
signs that indicate deterioration in the grease in order to beable to replace it in time. As such, the predecessor instituteto RTRI established a set of standard reference values
for replacing the grease, relating to grease deterioration.
Recent years have seen an increase in the use of highthermal-resistance lithium complex soap grease with theintroduction of induction motors on trains, which havefaster bearing rotational speeds and higher temperatures.
As a result, cases have been discovered where the levelof deterioration in the grease does not correspond to thereference value, i.e. changes in the dropping point, fordetermining the thermal resistance of that kind of grease.

In addition, it has become clear that there is a need tounderstand the effect of increases in ferrous particles in
the axle bearings from fretting wear, and the impact ofdifferences in oil separation calculation methods, on thereference value. Then, based on insight gained into deterioration mechanisms during laboratory tests (Fig. 2) andresults of surveys into the deterioration of grease used on
actual trains, a new set of reference values were proposed
for managing the grease in relation to the three exposed
problems (Table 1). The new criteria make it possible tocorrectly evaluate the state of new types of grease being
used, which the existing criteria could not achieve. They
can also be used to determine when the grease should be
replaced (frequency), and periodicity of inspection.

Table 1 Revised grease management criteria

Fig.1 Grease in use

Fig.2 Change in dropping point mechanism

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Railway Technical Research Institute

8. Method for detecting step-shaped wear on contact strips on
pantograph heads• In order to prevent damage to overhead contact lines, a method for detecting step-shaped wear on
contact strips on pantographs has been developed. In addition, a data acquisition device suited to thismethod has also been developed.
• RTRI then drafted some technical recommendations for railway operators on the practical applicationof the system.
Step-shaped wear on pantograph head contact strips
can cause serious damage to the pantograph and catenary
system. A method for detecting step-shaped wear has
therefore been developed. In this method, step-shaped
wear can be detected by measuring the axial forces
acting on steady arms installed on three adjacent supporting points (Fig.1). This method has few constraints
with regards to where it can be applied. In addition, acompact light-weight and power saving data acquisition

device consisting of a dynamic strain amplifier and data
telemetry system were also developed (Table 1, Fig. 2) tosuit this new detection method. Fig.3 shows an exampleof the application of the new method and the device to acommercial railway line. When the system detects certain
specific features in the forces exerted on the steady arm,the system immediately triggers and alert to the transport
control centre etc.

Fig.1 Axial force fluctuation acting on steady arm(result of field tests)

Fig.2 Example of the method applied in practiceTable 1 Specifications of the developed
data acquisition equipment

Fig.3 Example of developed data acquisition

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Major Results of Research and Development

9. Improving lightening resistance of electrical equipment using
new grounding structure• A new grounding structure was developed to improve the lightening resistance of electrical equipment.
• Compared to existing structures, the potential-rise due to lightning strikes is reduced by approximately
50% and voltage difference by about 60%, cutting the frequency of estimated lightning damage byapproximately 20%.
As a countermeasure to earth fault and lightning strikedamage to substations etc, wire mesh (bare copper
stranded cables) is often buried around/under the equipment and connected to earthing rods to form a grounding
structure (Fig.1 ). However, this existing structure was
optimised for use with low frequencies, and is no longer offers adequate protection for today’s substations equippedwith information communication technology (ICT).
As such, a new grounding structure has been designed.
Given that potential rise in the grounding structure whenlightening strikes may damage electrical equipment, flat
rectangular section bare copper wires, which facilitate theflow of high frequency current were employed to reduce
this problem (Fig. 2).
Experimental set ups were installed in the ground,as shown in the figures, for comparative tests. Results
showed that the maximum voltage at the injection point to

Fig. 1 Existing grounding structure and test conditions

Fig. 3 Reduction of voltage rise at injection point (in relation
to 100% being the maximum voltage under existing system)

12

the new structure could be made 50% lower than in existing
structures (Fig. 3).
Following on, voltage difference which occurs ingrounding structures reduces the effectiveness of lightning protection devices such as lightning arresters, and isanother cause for damage to equipment. Therefore, coatedrectangular-section copper wires, with better voltage transfer charcteristics were connected in parallel. As a result,the maximum voltage difference between the injection
point and the the end point was reduced by approximately
60% (Fig. 4).
Considering past data and the two results describedabove, it is expected that lightning damage can be decreased by 20%. Since the proposal requires changing thetype of wire and double layered wires, introucing the thesystem will incur some cost, however, in relation to overall
work on substations, the cost is relatively small.

Fig. 2 Proposed grounding structure and test conditions

Fig. 4 Reduction of voltage difference between injection
point and end point (in relation to 100% being the maximum
voltage under existing system)

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Railway Technical Research Institute

10. Proposal of method for diagnosing health of concrete
masts for maintenance• Through surveys on the health of concrete masts, conducting bending strength tests and materials
analyses, insight was obtained into the processes involved in concrete mast deterioration.
• A new method was subsequently proposed to diagnose the health of concrete masts.
Concrete masts (hereafter ‘masts’) have been in mainstream use on the railways for over 50 years, and there isa need to determine what criteria and grounds should be
used, in terms of degradation, to decide when to replacethese masts.
To this end, the state of health of 500 masts was surveyed along a stretch of commercial line, including bending
strength tests and materials analyses. Results showedthat the main process generating mast damage was ‘crack
precedence’ i.e. the appearance of cracks followed bydeterioration of the construction material, for example rebar
corrosion in the cracked areas.
Based on this deterioration process, a method was proposed for diagnosing the health of masts, for maintenance(Fig. 1).
The diagnosis is made in several steps, starting withthe existing visual inspection of masts. When there is noapparent alteration, a ‘materials evaluation’ is conducted,
whereas a ‘strength evaluation’ is made if alteration isobserved.

The materials evaluation carried out when no apparent
alteration is observed involves testing for neutralization of
the concrete surface, which is a typical sign of concrete
deterioration. The progress of neutralization in masts
is significantly slower than on civil structures, therefore
thorough testing is required with testing of the surface toa depth of 1 mm.
In the case of strength tests conducted when apparent
alteration has been observed, a ‘strength evaluation sheet’
was designed showing the correlation between bending
strength and external circumference of the mast, making
on-site diagnosis possible by checking whether the mastmeets level 2 safety requirements contained in the regulations for railway technical standards.
If the external circumference of the mast is within theadmissible limits, then the mast can remain in place,otherwise, it is marked as needing to be replaced.

Fig. 1 Outline of diagnosis flow chart to check the health of concrete masts

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Major Results of Research and Development

11. On-board platform detection device to assist train crew intrain door operation• A device was developed to identify which side of the train the platform is on by image detection of the
train stopping position signs.
• By adding gyro-sensor and GPS functions, the platform can be detected in over 90% cases evenwhen covered in snow.
• A device was proposed to assist on board staff operating train doors.
In order to prevent train doors being operated incorrectly, image analysis using an onboard camera andsensor technology have been used to develop a system
to detect the presence of a platform alongside a train, andhelp train staff operate train doors.
Detection through image analysis offers significant
advantages compared to ultrasound sensors and tags,
since it does not need special sensors on the platform
side, functions regardless of the shape and height of theplatform and operates even in deep snow.
Given the potential influence of environmental conditions on image processing, such as changes in lighting, thestopping position sign is detected using contour data based
pattern matching, and an algorithm has been developed
to identify the platform side of the train (Fig.1).

In addition, a method was developed to identify theplatform at which the train arrives, by combining data collected by the gyro-sensor on the yaw angle of the train as
it passes through points which helps determine the pathtaken by the train, with GPS and station layout information(Fig.2).
Field test results showed that the presence of a platform
was correctly detected in over 90% of cases (Fig.3).

Fig 1 Results detecting train stopping position sign using the pattern matching method

Fig 2 Onboard platform detection display

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Fig 3 Test conditions for platform detection in winterwith Full HD camera

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Railway Technical Research Institute

12. Human factor analysis method using Potential Incidents
Reports• A method has been proposed to improve the effectiveness of analyses conducted using the RTRI
Human Factor Analysis method• Employing Potential Incidents Reports to promote better organizational and work systems.
Applying the RTRI Human Factor Analysis method foranalysing the underlying human factor related causes
becomes time consuming when a large number of error
incidents have to be examined and analysed. As such a
new procedure has been developed to improve processing
efficiency using potential incidents reports (Fig. 1).
In the existing method, time series contrastive analysis
was applied based on the difference between “Objective
required by the system” and “actual action” to identify“deviations”, whereas in the new method the object of theanalysis is limited to identify errors carrying a major risk
using potential incidents reports (Hiyari-Hatto).
A “Root Cause analyses (Why-Why analyses) support
tool” was developed to extend the investigation into thetheoretical causes leading to the detected human error.
Then, based on the analytical results of the causal

Fig 1 Outline of human factor analysis method
using potential incidents reports

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analysis hand of 900 error cases and their causes, an iterative process using the question “why” is used to elucidate
possible origins of the case in hand.
A “Human Factor countermeasure design flow chart”
was devised to ensure that corrective measures weremore than just a one-off remedy and contributed to lasting
improvements in the organisation of work (Fig. 2), withadditional considerations such as “raising awareness of
relevant parties” etc. The process is divided into 9 steps
organised in hierarchical order, aimed at ensuring that theapplicable measures are feasible can be implemented insuitable conditions.
This method uses potential incidents reports for safety
management system and theoretical human factor analysis
aims to promote better organisation of work.

Fig. 2 Outline of flow chart to consider humanfactor based countermeasures

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Major Results of Research and Development

HARMONY WITH THE ENVIRONMENT
13. Sheet pile reinforcement work on pile foundations during
ground liquefaction• A reinforcement technique has been developed using the addition of steel sheet piles with closed
sections at the bottom to existing pile foundations during ground liquefaction.
• Confirmation was obtained that this new technique can reduce the working load on existing pilefoundations by 30%, and a guide to use of the technique was compiled.
• This reinforcement technique costs approximately 20% less to apply than existing methods.
When liquefaction occurs during earthquakes, theground suddenly loses its rigidity and hardness, leading
to extensive pile foundation damage (Fig. 1).
Existing countermeasures to protect pile foundations
from ground liquefaction, such as additional pile systems
and soil improvement methods involve a major increasein the basic dimensions of the structure, which is difficult
to apply when limited space is available.
Work was therefore undertaken to find a new method
which would not require a great amount of space, andwhich was practical and economical to implement. As
such a sheet pile reinforcement method was developed
using steel sheet reinforcement which improves both theFig. 1 Damage to pile foundations from ground liquefaction

supporting force and rigidity of the structure (Fig. 2).
After clarifying the reinforcement mechanisms of steel
sheet piles during shaking table tests on models using the
new technique, confirmation was obtained that the developed method reduced shearing forces on the pile headby approximately 30% and axial force by approximately
20% (Fig. 3).
A manual for the technique was then compiled using
insights gained from tests. Test designs produced following
the manual showed that the cost of reinforcement work
could be reduced by about 20% compared to existing
methods.

Fig. 2 Sheet pile reinforcement method

Fig. 3 Large shaking table tests confirmed the effectiveness of reinforcement work during ground liquefaction

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14. Countermeasure for fatigue cracks around I-beam bridge
supports• A method has been developed to repair fatigue cracks around I-beam bridge supports by covering
the end of the girder with concrete.
• The method can be applied to most I-beam bridges which have a span of less than 7 m.
• The repairs can be completed quickly, and represent approximately 1/3 of the cost of replacing thebridge.
I-beam bridges are short span bridges built with smallsection I-shaped steel beams, and often suffer fatigue
cracks around the bridge supports (Fig 1).
It is difficult to patch the beams with repair plates overthe fatigue cracks since crack initiation is located in transition area between the bottom flange and the web of thebridge support. Since no other effective countermeasure
to this problem existed until now, this type of damage often
led to the replacement of the bridge. Therefore, to solve
this problem a new repair method has been developed
whereby the end of the girder is covered with concrete(Fig. 2).
The method can prevent the fatigue crack propagation

Fig.1 Fatigue cracking around the I-beambridge support

Fig.3 Loading tests (full scale)

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because the stress around the crack is drastically reducedby the concrete which supports the train load (Fig. 3 and 4).
This method was developed for small-section structures, and is applicable for most I-beam bridges that havea girder length of less than 7 m.
Fatigue cracking is caused by damage to the bearing
seat mortar (Fig. 2), so existing methods require large
scale work such as girder jacking to repair the bearing seatmortar. With this new method, it is not necessary to repair
the bearing seat mortar, nor is it necessary to jack thegirders. Repairs using the new method can be conducted
fairly rapidly and reduce the costs by one third compared
to bridge replacement.

Fig. 2 Concrete casing method

Fig.4 Effectiveness of the method (test results)

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Major Results of Research and Development

15. Countermeasure work on ballasted Shinkansen track toprevent ballast migration• Ballast migration on a ballasted Shinkansen track was reproduced by vibration machine, producing
insight into the mechanisms leading to this phenomenon.
• A countermeasure was developed using biodegradable aqueous polymer solution to stabilize theballast on the track.
• This measure manages to reduce costs by 50%, and allows tamping work to be conducted after theprocedure.

18

On ballasted Shinkansen track, in curves with large
cant the surface ballast flows from the outer rail towards
the inner rail due to the passage of trains, which cancause “ballast migration”, and lead to a frequent need formaintenance work.
As a measure to counteract this phenomenom, avibration machine was employed with controllable load
direction, to conduct repetitive tests taking into accountthe excessive centrifugal force which occurs when a train
runs through a curve (Fig. 1). The results of these tests
showed that it was possible to reproduce ballast migration
through tests conducted inside (Fig. 2).

Results from investigations into the mechanisms
producing ballast migration revealed that dynamic displacement of the sleepers was causing the ballast to
shake, and that using rectangular section sleepers andtrack bed improvement were effective. An additional
low-cost countermeasure involved using a biodegradable
aqueous polymer solution to stabilise the surface of theballast (Fig.3 and 4). This method is approximately 50%
more economical than frequent ballast scraping work, andallows tamping once work has been completed.

Fig 1 Loading tests taking into account excessive
centrifugal forcesFig 2 tests to reproduce ballast migration

Fig 3 Stabilization of ballast using polymer
solution

Fig 4 Confirmation of effectiveness of ballast
migration countermeasure

Annual Report 2015-2016

Railway Technical Research Institute

16. Method for detecting damage and repairing slab track
cement asphalt mortar layers• A method has been proposed to use track inspection data to detect damaged sections in the CA
mortar layer under slab track.
• A method for repairing the gaps in the upper CA mortar layer was developed, which reduces material
costs by 40% compared to existing renovation methods.
• A method was then developed to carry out repairs on large-scale damage to the CA mortar layer.
This new renovation method reduces costs by 50% compared to present methods which completely
replace the CA mortar layer.
Slab track can be subject to major damage due to gaps
forming underneath it or erosion on its sides up to several
dozen centimetres in size, due to frost damage etc. Thiskind of damage is very cumbersome to repair. The change
in support due to deterioration appears on each 5m track
slab. Using this characteristic, a more efficient method by
5m-chord longitudinal level irregularity was proposed todetect deteriorated slab track sections from track inspection data (Fig. 1).
Gaps under track slabs can be repaired using resin
injections. However, due to cost of materials and workability, this method is seldom employed. As such, a new
method for renovating slab track was developed which
reduces costs by 40% compared to existing materials. The

method uses high-fluidity CA milk (slurry) injected using asandy mould to fill the gap (Fig. 2).
A new method was then developed to renovate large
sectional areas, whereby an inspection rod is used toestimate the extent of the deteriorated area, which issubsequently cleared using a water jet and then injectionfilled using frost-damage resistant renovative CA mortar(Figs. 3 and 4). This method reduces the cost of repairingdamaged sections by 50% compared to present methods
which completely replace the CA mortar layer.
Results from applying the gap repair and large-section
renovation work to a commercial line demonstrated thatdynamic displacement of the track was reduced, and could
be kept below 1/10 (Fig. 5).

Fig.1 Correlation between longitudinal level irregularity and track slab displacement

Fig.2 Gap repair method

Fig 3 Example of extensive
deterioration (condition at thesurface)Annual Report 2015-2016

Fig 4 Work with the water jet

Fig 5 Reducing dynamic displacement
through large section repair

19

Major Results of Research and Development

17.Decision-making support system for planning replacementof wooden-sleepers with PC sleepers in curved sections• A system has been developed to help plan replacement of wooden sleepers with PC sleepers according
to the specific characteristics of each curved section, its track structure, rolling stock and operating
conditions.
• This system can also be used to calculate the most appropriate distribution of PC and wooden sleepers
when carrying out partial replacement work.
• By using the system, it is possible to reduce the length of curves requiring replacement of wooden
sleepers with PC sleepers by approximately 15% compared to taking curves in order of radius size
starting from the smallest.
On curved lines with wooden sleepers, the lateral resistance of track panels is low, which can lead to excessive
lateral displacement of the track, and rotting of sleepers
which can then lead to derailment due to gauge-widening,
therefore wooden sleepers are gradually being replacedwith PC sleepers. Therefore, in order to prioritize whichcurves should have replacement PC sleepers first, adecision-making support system was developed to plan
replacements considering the conditions of each curved
section (Fig. 1).

Fig 1 Decision-making support system for planning replacement of wooden sleepers with PC sleepers

Fig 2 Example of partial installation of PC sleepers

20This system takes into account curve and track structure
characteristics, rolling stock and operating conditions andthe deterioration of the track. It calculates which curves
should be classed as high priority for installation of PC
sleepers through evaluation of several running safety
related factors, such as derailment due to gauge-widening,
track panel displacement and extrusion or falling out ofrail spikes.
Moreover, the system sets limit conditions, namely
budget and length of track requiring replacement work,and helps to plan replacement work efficiently by selecting
those curved sections which would most benefit in termsof safety improvement by having PC sleepers laid.
In addition, when wooden sleepers are partially replacedwith PC sleepers (Fig 2), the system can calculate theappropriate distribution of PC sleepers to be installed etc.
This function can be also used to set maintenance criteria
in terms of admissible number of successive damaged
sleepers, when carrying out sleeper inspections.
After trying the new system with data from a few line
sections, it was found that compared to tackling wooden
sleeper replacement by order of curve radius, starting withthe smallest, the length of track work on could be reduced
through this system by 15% whilst achieving the same
improvements in safety (Fig.3).

Fig 3 Curves selected for replacement with PC sleepers

Annual Report 2015-2016

Railway Technical Research Institute

18.System for inspecting obstruction warning signals• Using image processing technology, a system for inspecting Obstacle Warning Signals has beendeveloped.
• By applying the new system, signals can be inspected during daytime operating hours, thus reducing
the inspection time to 30% of the existing method, according to estimations on a model line.
Obstruction warning signals do not emit light during
normal service hours and therefore it is necessary to turnthem on to check their visibility during inspection. In order
not to affect railway operations, these inspections therefore
have to be conducted after normal operating hours. This
work is time and labour consuming and therefore a costly
problem.
As a solution, an inspection system has been developed
using near-infrared light invisible to the naked eye and acamera capable of picking up this near-infrared light, which

Fig 1 Outline of the new systemallows verification of the light emitted from the obstruction
warning signal from onboard a running train (Fig. 1).
The new system can be used to carry out inspections
during daytime operating hours, making the procedure efficient and cost effective. The prototype of this system, (Fig.
2: onboard measurement device; Figs. 3 and 4: Obstruction
warning signal) were monitored over an extended periodof time, confirming that the device can function unimpededby the weather, season or time of operation.
Image data for the whole line can be obtained in justone return journey, reducing the overall
inspection time in terms of days, to nearly
30% of the time required with the existing
method, according to calculations on amodel line. In addition, the new inspection
method is more accurate, since the obtained image is continuous and therfore
visibility can be inspected right up until
the train has passed the signal.
In order to implement the new method,
it will be necessary to replace existing obstruction warning signals with the newly
developed signals and equip trains withthe portable onboard inspection device.

Fig 2 Onboard device

Fig 3 Detection

Annual Report 2015-2016

Fig 4 Comparison between existing andnew obstruction warning signal

21

Major Results of Research and Development

19.Possibility of practical application of a 920MHz bandwidth
network• It has been demonstrated through experiments that wireless network technology using a 920MHz
frequency band has the potential for broad application in the monitoring of railway infrastructure andequipment, such as structures and railway vehicles.
• This type of network is unaffected by weather conditions and is capable of successfully transmitting
over 95% of various kinds of data.
In line with the growing use of the Internet of Things(IoT), wireless network technology is increasingly being
introduced for infrastruture monitoring systems using different frequency bands.
However, there is no standard network technology yet
which can be broadly applied to both structures in zones
where maintenance is difficult and to running trains.
As such, Wi-SUN (Wireless Smart Utility Network) technology, which was developed in Japan for the automaticcollection of gas and electricity meter data, and became
an international standard in wireless technology in 2012,
was evaluated in tests to assess its transmission capacity
in a railway environment to monitor the state of railway
infrastructure.
Wi-SUN is designed to carry data in small packets, andtherefore only consumes tens of mWs, which is a fraction ofelectricity consumption in other systems. Furthermore, theradio waves in the 920MHz band for which it is designed,
can propagate over longer distances than in the 2.45 GHzband used by other communication systems, and suffervery little interference. Results of tests conducted at RTRI
on a temporary test network set up using the test line, test
vehicle, heavy rain rig and snow obstacle test area, toevaluate data transmission performance of the network(Fig.1) confirmed that under various meteorological andclimatic conditions which can affect radio propagtion characteristics, on average over 95% of data was successfullytransmitted (Fig. 2).
Results from this study demonstrate that Wi-SUN
specifications can be broadly applied for the monitoring ofrailway infrastructure, and will the technology will therefore
be instrumental in developing a railway network technology
standard in the future.

Fig. 1 Structure of crowd based wireless sensor network and Wi-SUN in
verification tests

22

Fig.2 Results of evaluation of
successful data transmission

Annual Report 2015-2016

COST REDUCTION

Railway Technical Research Institute

20. Characteristics of long-term fuel cell deterioration• Before introducing fuel cells onto trains, their endurance for long-term use be tested through 3600
train runs and ten years of power generation tests.
• This paper proposes new fuel cell design guidelines based on risk assessments in the light of defectreports.
The introduction of clean energy fuel cells to trains isbeing eargerly awaited. In fuel cells a platinum catalyst
causes oxygen and hydrogen to react, generating electricity. The catalyst however suffers wear, which can cause
a fall in fuel cell output voltage and efficiency. Therefore,a ten-year continuous running test was conducted using
a test train with a fuel cell (Fig. 1) to investigate output
voltage and efficiency.
The experiment was carried out using a large capacity
fuel cell, capable of propelling a train, which showed thesame type of wear as smaller sized fuel cells, with a fallin output voltage of about 5% compared to initial values.

Efficiency however remained at about 52%, and it wasdemonstrated that even over a long period, there was no
significant decrease in fuel cell performance nor were there
any notable driving failures (Fig. 2).
Based on fuel cell problem reports, assessments weremade to establish the presence of unacceptable risks in thefuel cell due to age-related deterioration or an accidental
defect.
This process made it possible to identify the areas
requiring improvement, and made it possible to draft aset of new guidelines for a safer and more reliable newgeneration fuel cell (Table 1).

Fig 1 Fuel cell test railway vehicle

Fig 2 Change in fuel cell characteristics over the long term

Table 1 Example of Fuel cell risk assessment

Annual Report 2015-2016

23

Major Results of Research and Development

21. Quantification of impact noise due to local wear on
wheel treads on Shinkansen railway noise, and method for
detecting local wear.
• A quantitative investigation was made into the effect of impact noise due to local wear on wheel treads,
on Shinkansen railway noise.
• A method has been developed for detecting local wear above 0.1mm on wheel treads from vibrations
induced on viaducts.
• This method can contribute greatly to detecting local wheel wear, which affects wayside noise.
The impact noise due to local wear on Shinkansen train
wheel treads, when the trains are running at high speed,
contributes significantly to railway noise (Fig. 1). The contribution of the noise has not been understood properly,
nor has it been possible to detect local wear through visualinspection. Therefore, it is necessary to develop a method
which can identify the state of wheel treads.
Through the investigation of a large number of wheels,the geometry of those which affect wayside noise were
examined carefully, and it was found that the width of
typical local wear on the tread is about 300 mm, with amaximum depth of 0.5 mm.
Then, based on the relationship between bridge noise

and wheel roughness levels, based on the collected geometries, e.g. wear depth, it was confirmed that, when
the roughness level is greater than that corresponding
to a wear depth of about 0.1 mm, bridge noise increases
siginificantly (Fig. 2).
Examination of the correlation between the maximum
depth, δ, of local wear on the wheel tread and vibrations
induced on concrete viaducts suggests that the vibration
was approximately proportional to δ^1.8 (Fig. 3).
It is confirmed that, based on these results measured
with an accelerometer placed on the concrete viaduct, it ispossible to quantitatively estimate the depth of local wheel
tread wear above 0.1 mm in a single bogie.

Fig.1 Example of local wear on a wheel and influence on bridge noiseFig 2 Correlation between trackside noise (noise directly
beneath structure) and wheel tread roughness24

Fig 3 Relationship between vibration of a viaduct and wear
depth (extracting the component generated by local wheel
wear)

Annual Report 2015-2016

Railway Technical Research Institute

22. Verification of High Temperature Superconducting
Flywheel Storage Systems• A machine has been developed for verifying high-temperature superconducting flywheel storage
systems with contactless flywheel support, using high-temperature superconducting magnetic bearings.
• Confirmation was obtained using the verification equipment that a small high-temperature
superconducting magnetic contactless bearing was capable of supporting a 4-ton flywheel in a systemwith an output power of 300kW, and storage capacity of 25kWh.
Flywheel Energy Storage Systems work by having an
in-built flywheel (rotor), which changes the electric power
to kinetic energy which is then stored, and can releaseelectric power on demand by reconverting the kinetic
energy back into electricity.
The specificity of the flywheel energy storage systembeing verified in this paper is that it uses high-temperature
superconducting magnetic bearings. The system has ahigh-temperature superconducting bulk body rotating shaft
and high-temperature superconducting bearings, which
produces a step-change improvement in supporting force
and means that the bearing can be made relatively muchsmaller than before for the load it must support (Fig. 1).
The demonstration machine used for verification tests(Figs. 2 and 3) had a 2 m diameter and a mass of 4 tons,

supported by a CFRP superconducting magnetic-bearing
flywheel. Rotations were adjusted through the generator
motor; therefore, it was possible to test the system’s capacity to absorb and release 300 kW of power, and verify it
could store 25kWh of power.
The superconducting magnetic bearing was cooledwith a commercially available compact cooler, removing the need for liquid nitrogen etc., and electric power
consumption was less than 1% of output power. Since
September 2015 this demonstration machine has beenused in verification tests to equalize solar photovoltaic
power output (at the Yamanashi prefecture facility).
This storage system, apart from the fact that it does
not suffer wear from repeated charging and discharging,is low-loss, long-life and low-maintenance and is suited
for use on the railways for regenerative power purposes
and as a measure to prevent voltage dropping. The next
step will be to design the energy storage system for useon the railways.

Fig. 1 High-temperature superconducting
magnetic bearing structure

Fig.2 Outside view of the demonstration machine

Annual Report 2015-2016

Fig.3 Structure of the demonstration machine25

Major Results of Research and Development

IMPROVEMENT OF CONVENIENCE
23. Car-body tilt control system for better ride comfort• A control system was developed for tilting trains to mitigate motion sickness.
• The new system can reduce the motion sickness dose value in sharp curves by 30% and be installedon existing tilting trains.
• It is proposed that the system can be installed on not only new trains but also existing tilting trains
travelling through sections with successive sharp curves during their overhaul periods.
The car-body tilting mechanism with tilting bolsters androllers, while it is more complex than the mechanism with
air-spring systems, offers a larger tilt angle and optimal
reactivity, and is designed for trains which require betterride comfort or that must pass through sections with successive sharp curves.
The tilt control system was designed to provide improved ride comfort and reduce motion sickness through(1) precise train positioning, (2) tilt patterns offering better ride comfort, and (3) optimal response pneumatic tilt
actuators.
Table 1 compares the new mechanism with the existing
system. Ride comfort is improved thanks to a “Tilt pattern”
function which responds to curve radius, cant size andrunning speed, and produces successive predictions of theaccelerations exerted on passengers in order to suppress
the low frequency swaying action which causes motion
sickness.

Results from test runs confirmed that compared to theexisting system the new mechanism could reduce themotion sickness dose value (MSDV-y) by 30%, i.e. froma current average of 4.2m/s1.5 to 3.0 m/s1.5 with the new
system (Fig 1).
It was also verified that if the tilt actuator could be applied then existing tilting dampers were no longer required.
Based on these findings, further developments weremade to the device to incorporate features needed forthe system to be installed on commercial trains, suchas connectivity with monitoring equipment and failsafe
performance (Fig. 2).

Table 1 Comparison with the existing system

Fig. 1 Reduction in motion sickness dose value (MSDV-y)26

Fig. 2 Tilting control device adapted
for use on commercial trains

Annual Report 2015-2016

Railway Technical Research Institute

24. Design method and performance verification for linear
rail brakes used on high-speed trains• A design method has been developed to produce contactless, compact and light-weight linear rail
brakes which can still function during power cuts and can be used on high-speed trains.
• Based on model tests and simulations, it is expected that the new model linear rail brake will be able
to reduce the stopping distance after application of brakes at nearly the maximum running speed, by
about 10% compared brake systems using adhesion alone.
While plans are being made to increase train speed,
there is a concomitant need to increase the braking force
when wheel/rail frictional forces (adhesive force) decreaseat these higher running speeds.
A contactless and non-adhesive linear rail brake has
therefore been designed with this objective in mind. The
new brake utilizes the electromagnetic interaction with therail to produce the braking force while generating itself thepower required for excitation. This means that it can operate stably even in bad weather and through power cuts. A
design method was then devised and is proposed to build
a compact light-weight version of this brake especially
adapted for high speeds.
The iron core for passing the magnetic flux in the present design method is much smaller than in existing systems
which are designed to operate even at low speed. The
present design is geared to maintain braking force which
influences greatly the stopping distance at high speed.

After conducting detailed magnetic field value andstructural analyses and proposing a reinforced support
structure, the new design can reduce the iron core byapproximately 60% compared to the existing system.
A prototype suited for testing on a roller rig was thenbuilt applying the new design method described above(Fig. 1). Results after tests during a mock power cut confirmed that the same braking force could be obtained athigh speed as with the existing design, despite the lower
weight (Fig. 2). Using the test data, simulations were thenconducted using the system together with adhesive braking to measure stopping distances when running at nearlymaximum speed. The simulations demonstrated that the
stopping distance could be shortened by approximately
10% compared to when adhesive braking (applied at theadhesive limit in dry conditions) is used alone.

Fig.1 Picture of basic structure of the linear rail brake (top)and prototype built for tests on the roller rig (bottom)

Fig. 2 Braking force test results

Annual Report 2015-2016

27

Major Results of Research and Development

25. Method for predicting passenger thermal comfort inrailway vehicles• A method has been developed to predict passenger thermal comfort which correlates closely with thephysiological and psychological state of passengers.
• Subjective experiments in thermal environments were conducted in main line and commuter vehicles.
Results demonstrated that the proposed prediction method reflected passenger thermal comfort
accurately, with a correlation of over 0.8.
In order to improve the on-board thermal environment
for rail passengers, it is important to be able to accurately
evaluate and predict thermal comfort levels. A methodfor determining thermal comfort already exists for indoor
spaces in the ISO 7730. However, there is no standard
specifying a similar method for the railway environment
which has specific characteristics, for example, contrary
to indoor spaces, temperature and humidity variation in
railway vehicles can be very drastic, and there are alsosignificant differences in thermal comfort from season toseason. Consequently, taking these specificities into account, a new method has been proposed for determining
thermal comfort levels specially adapted to railway rollingstock (Fig. 1).
The proposed method is made up of physiologicaland psychological predictions. A human thermal modelwith a built-in body temperature regulation function
is used to estimate the various thermal physiologicalstates of the passenger, such as skin temperature andperspiration in various thermal environments in railway
vehicles. It is also possible to take into account the clothing
and posture of the passenger in these estimations. To
estimate psychological states, a statistical model is built
on data collected from subjective experiments conductedin railway vehicles stationed at rolling stock centers in
different seasons (a total of 350 people for a temperature
range of 20℃〜32℃), and this is applied to predict passenger thermal comfort (level of discomfort and percentage
of dissatisfied customers).
Comparing predicted thermal comfort results with theactual comfort of subjects participating in a simulated thermal experiment revealed a correlation of over 0.8 between
them (Fig. 2, Fig. 3). This method will make it possible toquantitatively evaluate air-conditioning adjustment from thepassenger thermal comfort perspective in railway vehicles.

Fig. 1 Overview diagram of the proposed thermal comfort prediction method for thermal environments in railway vehicles.

Fig. 2 Example of dissatisfaction level prediction in relation
to thermal environment, using the proposed method

28

Fig. 3 Comparison between actual comfort level values andpredicted comfort levels using the new method

Annual Report 2015-2016

Railway Technical Research Institute

26. Training support program to foster resourcefulness when
making PA announcements during disruptions• A training method has been proposed to encourage train conductors to be more resourceful when
making PA announcements during disruptions, and a training program has been devised to support
trainers when conducting on-site practice sessions.
• After training train conductors with this method, their resourcefulness improved by approximately 20
points on the evaluation scale.
• The method has been proposed in the form of “study support material” and “trainer and evaluation
support material” for trainers.
A method has been proposed to improve the level ofresourcefulness among those having to make announcements during disruptions. In addition, a training support
program has been devised (Fig. 1) aimed at trainers
conducting on-site practical sessions. Part of the support
program includes two types of teaching material to help
trainers in learning, teaching and evaluating the subject.
Learning support material (bird’s eye approach to learning how to make announcements in DVD, handbook andpractical study format)
Trainer/ evaluation material (Step-by-step slides, study
topics, announcement evaluation sheet)
The proposed training program was tried as part of
conductor training in the railway companies in metropolitan
areas (approximately 400 participants).

Fig.1 Outline of training support program

The conductors’ announcing skills were measured inpractical tests before and after the training by asking themto make improvised announcements for mock cases, suchas an interminable disruption requiring repeated updatesof the situation, or other possible difficult scenarios. Theirperformances were given a score reached on a set ofcheck-list items from existing manuals for the ‘basic score’,and according to another set of check-list items to measure
resourcefulness, for the ‘responsiveness score’ (Table 1).
Comparison of their scores before and after the training(Fig.2) showed that their basic score had improved by
10 points, whereas resourcefulness had improved by 20
points on the scale. This confirmed that the newly proposed program aimed at improving the announcing skillsof railway staff is effective.

Fig.2 Number of check-list items in relation
to score achieved in practical skills test

Table 1 Example of practical skills test score reached and check-list items

Annual Report 2015-2016

29

Major Results of Research and Development

27. Improvement of visibility of Tactile Walking Surface
Indicators (TWSIs) for people with low vision• Investigations were conducted into suitable specifications for the continuous adjoining bands (CAB)
to improve the visibility of tactile walking surface indicators (TWSIs).
• A proposal was made to make CABs about 5-15 cm wide, with a luminance ratio of about 3, at least,
when used with TWSIs.

30

Visibility of tactile walking surface indicators (TWSIs)
is important for people with low vision when they walk bythemselves, since people with low vision, approximately
90% of the blind and vision-impaired persons, use residual
vision in their independent travel. Visibility of TWSIs is
determined chiefly by the luminance contrast between
TWSIs and their surrounding surfaces. In this study, three
investigations were conducted concerning the luminanceratio, an index of luminance contrast, between TWSIs andtheir surroundings, as follows.
First, the relationship between the luminance ration of
TWSIs and the surrounding surfaces, and the visibility of
TWSIs was examined. Forty-six people with low visionparticipated in this investigation. Results demonstrated therelationship between luminance ratio and the percentageof those with low vision who find the visibility of TWSIs to
be unacceptable (Figure 1).

Second, some previous studies showed that when theluminance ratio is insufficient (Fig. 2), continuous adjoining
bands (CAB) of dark color can be used to improve thevisibility of TWSIs (Fig. 3). Some other previous studies
however warn that bands of dark color on the walking surface may be falsely recognized by people with low vision
as street gutters, depending on their color and/or width.
Investigations were conducted to identify the optimal color
and width of CABs which improve the visibility of TWSIs
without being mistaken for street gutters. Forty-four people
with low vision participated in this investigation. Based on
the result, it was proposed to make CABs 5-15 cm widewith a luminance ratio of about 3, at least, when used withTWSIs (Figure 4).
Finally, a manual was proposed containing methods formeasuring the luminance ratio between TWSIs and theirsurrounding surfaces, taking the environmental characteristics of railway stations into consideration.

Fig.1 Proportion of subjects with low vision
who find visibility unacceptable

Fig.2 Example of location with low luminance ratio

Fig.3 Example of continuous adjoining bands (CABs)
with TWSIs

Fig. 4 Ratings for different CAB width/luminanceratio combinations

Annual Report 2015-2016

BASIC RESEARCH

Railway Technical Research Institute

28. Obstacle monitoring system using 90GHz band
millimeter wave
• A new monitoring system has been proposed which combines a 90 GHz band millimeter wave not
yet used in the railway environment and Radio over Fiber technology.
• It has been confirmed that the system can detect the presence of a small group of people from a
distance over 100m with a resolution of 50cm.
The characteristics of 90 GHz band millimeter waves
include low attenuation due to dry air and the fact that they
can be used in a wide frequency range. Therefore it canbe applied to radar systems able to detect obstacles withhigh resolution from a long distance.
By applying Radio over Fiber (RoF) technology whichtransmits radio frequency signals through over opticalfiber, it is possible to bring together control units whichhave the function of costly millimeter-wave signal sources
and signal processing units, simplifying the configurationof the radar nodes installed on the trackside, in order totransmit and receive the radio waves. Compared to theexisting systems, it is expected that the proposed new

system will cut installation costs by more than half (Fig.
1). A prototype system constituted by combining a 90 GHz
band millimeter-wave and RoF technology was installed
and the verification test was carried out. As a result, it
was confirmed that a group of several people can be
distinguished from a distance of over 100m and people andconcrete blocks can be detected from a distance of about
200m (Fig. 2 and Fig. 3). These research results havedemonstrated that it is possible to apply available radio
resources in the form of 90GHz band millimeter waves
that were not used until now in the railway environment todetect obstacles on railway tracks.

Fig.1 Configuration of the proposed future track monitoring system

Fig. 2 Received power of radar

Annual Report 2015-2016

Fig. 3 Example of display of detection result31

Major Results of Research and Development

29. Simulation of contact between running railway vehicles
and railway structures during earthquakes• Previously, due to unfeasible calculation times required, it was not possible to analyze contact between
running railway vehicles and railway structures during earthquakes. However, a new method has now
been developed with feasible calculation times to analyze such situations, in order to evaluate theeffectiveness of derailment damage mitigation measures such as L-guides and vehicle guide guards
during very large earthquakes.
• The new method can be used as a tool to evaluate the effectiveness of derailment damage mitigation
measures and analyze vehicle contact with railway structures in case of a derailment.
In order to carry out efficient simulations of runningtrains coming into contact with railway structures, a newalgorithm was developed (Fig. 1). The new algorithm
calculates contact between contact points placed on amultiple-body vehicle model and contact surfaces on 3D
FEM-model railway structures.
Since this method significantly decreases the degrees
of freedom in the analytical model, calculation times are
significantly shorter than in the previous method where
only FEM models were used. This means that practically,
contact phenomena can be calculated in units of tens ofseconds using this analytical method. The vehicle/railway
structure contact model was also constructed using resultsfrom other detailed FEM analyses and actual large scalemodel experiments.

Fig. 1 Schematic diagram of proposed algorithm

32

Integration of this new contact-algorithm into the
dynamic interaction analysis program DIASTARS for
Shinkansen trains and railway structures, has made it
possible to quantitatively evaluate railway vehicle behavior
and contact forces, taking into account contact with railway structures (Fig. 2 (a)). This method can also perform
stable calculations in cases with non-linear contact force
characteristics (Fig. 2 (b)).

Fig. 2 Analysis using the constructed analyticalmethod (Derailed running vehicle coming into
contact with through girders)Annual Report 2015-2016

Railway Technical Research Institute

30. Aerodynamic characteristics simulation method
capable of reproducing crosswind wind tunnel tests• A numerical flow simulation method has been developed capable of reproducing crosswind windtunnel tests.
• It was confirmed that the simulation method could predict the side force coefficient in wind tunnel
tests within a maximum 20% error margin.
• This simulation method can be used to narrow down certain test conditions and thereby be used asa tool to improve testing efficiency.
To ensure the operating safety and stability of trains instrong crosswind, it is important to understand the aerodynamic characteristics of railway rolling stock exposed tocrosswind, and currently these are evaluated in wind tunnel
tests. However, it is very difficult to verify all necessary
conditions in wind tunnel tests, and therefore a numericalsimulation method capable of reproducing crosswind windtunnel tests was developed.
The computational domain was a wide area including
the turbulent boundary layer generation installations (Fig.
1), which meant that the computational cost was formidable. However, by separating calculation of the turbulent
boundary layer from calculation of flows around the railway
vehicles (Fig. 2), it was possible to shorten calculation
times.

Fig. 1 Computational domain

Using the simulation method to calculate flows arounda railway vehicle on a viaduct and then an embankment
showed that the calculated results were within a maximum
error margin of 20% in relation to wind tunnel experimentresults, demonstrating its ability to effectively reproduce
flows (Fig. 3 and Fig. 4).
This simulation method can therefore be used to narrow
down certain test conditions and thereby be used as a tool
to improve testing efficiency.

Fig. 2 Separation of computational
domainFig. 3 Results of turbulent boundary layer
calculation

Fig. 4 Computational results for the flow around the railway vehicle with the inflow turbulent boundary layer

Annual Report 2015-2016

33

Results fromindividual R&D divisions

1

Vehicle Structure Technology
Division

The Vehicle Structure Technology Divisionconsists of four laboratories, namely, the Vehicle
Dynamics, Running Gear, Vehicle Noise andVibration, and Vehicle Strength Labs. They are
responsible for a wide range of matters related
to safety, stability, comfort, durability etc. The following is an outline of various research activitiesof the Division in FY2015.
The Division worked on a total of 23 researchand development themes, of which 3 were related
to “Research and development for the future ofrailways”, 5 to “Development of practical technologies”, and 15 to “Basic research for railways”.
The Division responded to requests for
consulting advice from railway business operators including investigating incidents suchas equipment failures and accidents, studying
countermeasures, and clarifying the performanceof new vehicles. Contract work, in addition to individual requests from railway business operators,
included conducting survey research (entrusted
by the national government) on the impact ofvibration of vehicle equipment.

■ Vehicle Dynamics

The Vehicle Dynamics Lab develops safety
evaluation methods and simulation technologies
related to the running safety of vehicles. In adevelopment project titled “Clarification of wheel
wear generation mechanisms,” wear analysis
found that wheels exhibited more wear when
shaken laterally at frequencies higher than 1 Hz,
while running stability analysis found that evenlight concave wear affected running stability andride comfort. In a study titled “Clarification of theamount of container car vibration,” a method for
estimating separation between container cars
and the track clearance envelope was proposed
based on running test results.
In a study titled “Method for improving vehicles’
anti-overturn performance against cross wind,”34

vehicle specification impact sensitivity analysis
found that the vehicle’s anti-overturn performance
was affected significantly by the mass of the carbody/bogie, the heights of the carbody’s center ofgravity and the carbody’s lateral area. In a study
titled “Carbody suspension system using air
springs with less air consumption,” preparations
were made for a stationary test by developing a
hybrid simulation environment with a combinationof test equipment and simulation.

■ Running Gear

The Running Gear Lab works to develop ways
to improve the functions of vehicles and riding
comfort. In a development project for carbody
tilting technology, a tilt control system was developed that reduces motion sickness. A pneumatic
centering cylinder was developed that dampens
lateral bump stop contact for vehicles which tilt
their bodies with air springs (Figure 4-1-1).
In a development project for a rapid prototyping
bogie, an actuator control method was developedthat prevents dynamic coupling between actuators. A bench test confirmed the method is capableof reproducing bogie motions. Also, a prototype
vertical vibration control system was developed
to improve the ride comfort in high-deck vehicles.
The improvement was confirmed in a running test.
Two development projects were conducted
for steering bogies. In one project, running tests
confirmed that an axle box suspension using
magnetic elastomers that have a variable coefficient of elasticity depending on magnetic fields
achieved the expected improvement in curving
performance. Secondly, specifications were considered for a bogie angle steering system where
hydraulic actuators can supplement the active

Fig. 4-1-1: Pneumatic centering cylinder

Annual Report 2015-2016

Railway Technical Research Institutesteering force of the ordinary bogie angle linked
steering mechanism. In another development
project, it was confirmed through field tests thatmultiple wireless modules formed a mesh topology of a wireless network. This work is related tothe implementation of bogie condition monitoring
systems.
Two further evaluations are notable. In one,
simulations verified the impact of wheel diameter on axle box acceleration that is generated
on a wheelset with flats. In the second study,
on running stability evaluation methods using
rolling stock test equipment, a review was madeof excitation methods and evaluation criteria.
Excitation methods were examined to determine
possible impact on the critical speed of hunting.

■ Vehicle Noise and Vibration

The Vehicle Noise and Vibration Lab conducts
research and development to reduce vibrationand interior noise for higher standards of interior
comfort. In a project to reduce the elastic vibrationof carbodies, a vibration test using a rolling stock
test stand confirmed that vibration was reducedwith a movable yaw damper and multiple axle
deforming elastic torus, both of which weredeveloped in the project. Also on the subject ofvibration, in a study on improving the accuracyof a carbody vibration analysis model, a method
was proposed for estimating parameters for the
analysis model based on measurements taken
during vehicle running. The accuracy of the analysis model was verified by comparing calculations
based on input of measured track irregularity withthe measurements.
In a study to reduce interior noise on Shinkansen
trains that join its bogie and carbody, the contribution of components to interior vibration and noise
was clarified by a transmission route analysis.
The contribution of interior vibration to interior
noise was calculated based on the velocity of
acoustic particles near the interior decoration andfloor boards. An independent one-piece interior
decoration structure, which had been proposed
Annual Report 2015-2016

as a measure to reduce interior noise, was madeabout 3.2 times more rigid by improving the structure of the bottom surface reinforcement of thedecoration’s floor board. A vibration test using
a test vehicle fitted with the interior decoration
confirmed the effectiveness of the decoration
structure in reducing the vibration and noise of
the suspended floor.

■ Vehicle and Bogie Parts Strength

The Vehicle and Bogie Parts Strength Lab conducts research on the evaluation of the strengthof car bodies and bogie components and on nondestructive inspection technologies. In a study on
vehicle crashworthiness, quasi-static compressive
failure tests using an actual coupler were carriedout in order to achieve crash behavior of a coupler
under extremely large compressive loads. Fourdifferent angles of a coupler body were applied
for these tests. FEM analyses were carried out tovalidate the test results (Figure 4-1-2). Moreover,the FEM analysis model of a train set including
this coupler model was built for the purpose ofevaluating the crash behavior of train sets, anda study on the improvement of crashworthiness
was conducted using this model.
In a study on the evaluation of axle strength,a fatigue testing methodology under variable
amplitude tests based on an in-service stress
spectrum was proposed to evaluate the crack

Fig. 4-1-2: FEM analysis model of a coupler

35

Results from indivisual R&D divisions

growth behavior of railway axles. Full-scale axle
specimens with a fatigue pre-crack for crack
propagation tests were fabricated.

2

Vehicle Control Technology
Division

The Vehicle Control Technology Division consists of four laboratories, namely, the Traction
Control, Hydrogen and Sustainable Energy, Drive
Systems and Brake Control Labs, which are primarily responsible for research and development,
consulting and contract work on instruments andcontrol; technologies to evaluate and reduce running resistance and energy consumption; andnew circuit technologies, such as hybrid systems,
storage battery systems and fuel cell power generation systems, related to traction and braking.

■ Traction Control

In a study on storage battery charge control
for a wider use of battery-powered railcars oncommercial lines, a thermal model of a storage

battery was developed to reflect the heat dissipation structure of the storage battery box on actual
vehicles. Using the model, the temperature riseduring a quick charge was computed.
An electric train set simulation model wasdeveloped as part of an effort to control the traction motor of an electric train set in response tochanges in tangential force during re-adhesion
control. Results from the simulation model were
found to agree with actual vehicle data.
In a study to simplify the inductive obstruction
test, maximum noise values were computed fora converter and an inverter in a return current
test for AC electric railcars. It was confirmed thatnoise components could be estimated up to the
maximum speeds of three car types based on
measured data.
As part of a study on a new traction circuit for
AC electric railcars (commissioned by the New
Energy and Industrial Technology Development
Organization (NEDO)), an experiment using a
mini model showed a possibility that a proposed
flying capacitor method could be used for the traction circuit systems not equipped with a traction
transformer.

Fig. 4-2-1: Trial design of equipment for fuel cell railcars

36

Annual Report 2015-2016

Railway Technical Research Institute■ Hydrogen and Sustainable Energy

The Hydrogen and Sustainable Energy Lab
was set up in May 2015 to conduct comprehensive research and development for practicalapplications of energy saving technologies andnew energy sources.
The laboratory has been pursuing the development of fuel cell powered railcars and energy
saving operations to help reduce the railway sector’s impact on the environment. Related activities
conducted in FY2015 included determining thelong-term deterioration mechanism of fuel cellsystems using an RTRI electric test vehicle,
downsizing of devices and trial designing ofequipment for fuel cell railcars operating on commercial lines (Figure 4-2-1). Energy consumption
simulations were conducted for specific revenuelines including the development of novel computation methods for computing running resistanceby analyzing mass data from train information
recorders on actual vehicles.

■ Drive Systems

The Drive Systems Lab has been working on
the development of methods for monitoring thecondition of engines, transmissions and otherdrive systems for diagnostic purposes, reductionof gear unit noise and for other research themes.
To help monitor drive systems, an error detection method based on octave band analysis ofvibration was developed. A prototype condition
monitoring device was made for collecting vibration data and a stationary test was conducted inwhich engine lubrication oil was contaminatedwith foreign matter to wear down sliding parts ofthe engine. The results showed that the method
was effective in detecting errors.
In studying methods to reduce gear unit noise,a gear unit rotation test was conducted to identify
the distribution of vibration on gear box surfaces
while a sound source search found that noise
was generated around plates near the gear bearings. In a related gear mesh sound simulation,
the noise reduction effect from changing gear box
materials was computed.

■ Brake Control

The Brake Control Lab conducts researchand development on the structure and control ofAnnual Report 2015-2016

Fig. 4-2-2: Results of bench test in low-adhesion condition

mechanical braking systems on Shinkansen andconventional line railcars. In an effort to develop
an improved slip control method that would prevent both stopping distance becoming longer due
to slipping during braking and wheel flats due
to wheel lock, a control method was proposedthat features a control function for adhesion in
macro slip regions where adhesion is unstable. Ina low-adhesion bench test, the proposed method
showed that in a braking test with an initial braking speed of 130 km/h, it could nearly halve thedecline in the deceleration rate of the existing slip
control (Figure 4-2-2).
In a project to develop a brake system for
Shinkansen consisting of a combination of nonadhesive brakes that do not rely on force acting
between wheels and rails, efforts were made to
reduce the current emergency braking distancefor next-generation high-speed Shinkansen. It
was found that a combination of a disk brakesystem and a small air drag brake has the potential to stop trains within today’s typical distances
but from higher speeds even in low-adhesion
condition.

3

Structures Technology Division

The Structures Technology Division consists offive laboratories, namely the Concrete Structures,
Steel and Hybrid Structures, Foundation andGeotechnical Engineering, Tunnel Engineering,37

Research and Development

and Architecture Labs, which are responsible forresearch and development, forming the relevant
technical standards, and consulting and contract
work related to these structures. Research anddevelopment covered such areas as improving
the efficiency of structure maintenance, aseismic
countermeasures including earthquakes thatmight directly hit the Tokyo area in the near future,and design methods and structures resistant totsunamis. Technical standards work included
developing a draft version of the cut-and-covertunneling section in order to bring the design standard for tunnels into alignment with performancebased design methods, while the processes todraft the technical standards sections on shieldtunneling and mountain tunneling methods werestarted.

■ Concrete Structures

The Concrete Structures Lab conducts research and development of technical standards
for concrete structures and is working on the
preparation of related manuals. It is also involvedin structural design methods and maintenancetechnologies. On technical standards, the laboratory worked on design methods for cut-and-covertunnels in consideration of tunnel durability andeffective measures to prevent the peeling of
concrete structures.
Research and development projects included
clarifying the wave force that concrete beams
are subjected to in tsunamis and the mechanism
involved when concrete beams are washed away.
These activities made possible the predictionof damage to bridges in tsunamis. In addition,

methods for preventing bridges being washedaway in tsunamis were proposed (subsidized by
the Ministry of Land, Infrastructure, Transport andTourism in its railway technology development
scheme). On maintenance technologies, research
was conducted on methods for accurately predicting the harmful and long-term deformation ofreinforced concrete structures.

■ Steel and Hybrid Structures

The Steel and Hybrid Structures Lab preparestechnical standards for steel and hybrid structuresand conducts research and development related
to design, maintenance. Regarding technicalstandards, the laboratory has cooperated with
the Concrete Structures Lab to publish the design
standards for steel and concrete hybrid structures and to conduct training sessions. It also
supplemented the maintenance standards, andcompleted the manuals on steel bridge inspection
and repair, which bring together information of use
in maintenance work.
Research and development work resulted ina concrete jacketing method being developed to
repair fatigue cracks which often occur in supports for short span steel girders (Figure 4-3-1).
Research was also conducted on design methods
for steel framed reinforced concrete through girders and rectangular section concrete filled steel
pipe columns as well as on redundancy inspections of steel bridges.

■ Foundation and GeotechnicalEngineering

The Foundation and Geotechnical Engineering

Fig. 4-3-1: Concrete jacketing method for short span steel girder supports

38

Annual Report 2015-2016

Railway Technical Research InstituteLab conducts research and development work torevise technical standards related to foundations
and earth structures and to develop soundness
evaluation methods and lifetime extension technologies for ground structures and reinforced
soil structures. The laboratory advanced therevision process for the technical standards on
cut-and-cover tunnels (guidelines on base unit
structure and soil retaining), published a manual
for aseismic diagnosis of railway earth structuresand held training sessions. It also published amanual for pile design based on the 2012 foundations standards as well as examples of design
calculations for steel pipe soil cement piles.
Research and development efforts resulted indeveloping a liquefaction countermeasure technical method for existing pile foundations using steel
sheet piles with a closed section at the bottom(Figure 4-3-2). Aseismic reinforcement technology for existing stone masonry retaining walls
using net and ground reinforcement material was
also developed. Systematic tests were conductedon the strength and rigidity of geo-materials andon the characteristics of partially saturated soil
in order to contribute to the design of new earth
structures and aseismic reinforcement of existing
earth structures. The studies required the use oflaboratory equipment and machines such as a
medium-sized shaking table, a dynamic and static
foundations loading machine and a soil element

tester for the torsional shear test.

■ Tunnel Engineering

The Tunnel Engineering Lab performs researchand development to enact technical standards
and to provide maintenance technologies, design methods, and construction technologies forrailway tunnels. To provide technical standards, it
conducted studies to revise the design standards
for cut-and-cover tunnels into performance based
design methods while also revising standards
for shield and mountain tunnels. Research anddevelopment resulted in the laboratory proposing lining reinforcement techniques for mountaintunnels under earth pressure and evaluating theeffects of reinforcement for mountain tunnels. The
Lab also worked on methods for evaluating thehealth of existing shield tunnels with deformation and for evaluating the ground deformationof thrusting elements on constructing structures
crossing under railroad track.

■ Architecture

The Architecture Lab performs research anddevelopment to improve the safety, convenienceand comfort of stations. From the viewpoint ofsafety, the laboratory is working on a seismic
resistance diagnosis tool for platform sheds anda seismic design tool for suspended ceilings instations. The laboratory also proposed concepts

Fig. 4-3-2: Liquefaction countermeasure technical method for existing pile foundations
using steel sheet piles with a closed section at the bottom

Annual Report 2015-2016

39

Research and Developmentof load fluctuation caused by passing trains andpassengers on falling protection facilities on
conventional line platforms. On improvement inconvenience and comfort, efforts were made to
develop improved public address methods forlarge concourses and methods for measuring
the relationship between passenger density andwalking speed in stations.

4Power Supply Technology
Division

The Power Supply Technology Division consistsof three laboratories, namely, the Power Supply,
Current Collection Maintenance, and Contact Line
Structure Labs. They are in charge of researchand development, consulting, and contracted
work intended to provide stable power to electricrailways. In FY2015, under one of the three R&D
Pillars, “R&D toward the future of railways,” thelaboratories tackled two individual R&D programsin one of three major challenges involved in thepillar: “Save energy by making better use ofenergy networks” which aimed to achieve higher
levels of energy saving through concerted efforts
by the ground, vehicle and operation divisions,and “Efficient maintenance with ICT” which aimed
to develop a maintenance system that offers more
efficient and accurate inspection.

Fig. 4-4-1: Ground system for enhanced lightning resistance40■ Power Supply

The Power Supply Lab undertakes researchand development to improve the energy efficiencyof the railway power supply system, reduce
equipment maintenance labor requirements, andenhance equipment protection. Under the “R&D
toward the future of railways,” energy efficiency
improvement efforts were launched to develop ahigh-tech rectifier capable of continuously controlling DC voltage using a variable reactor. On
reducing equipment maintenance labor requirements, under the“R&D of technology for practicaluse,” research was conducted on the evaluationof the remaining life of oil-immersed transformers
in which criteria suitable for train operation were
proposed regarding methods for estimating thedegree of degradation of insulating paper basedon the analysis of insulating oil.
On enhanced equipment protection, a newearth system was proposed that excels in limiting the potential rise in a lightning strike while
maintaining equipotential at substations. The
proposal is based on a past theoretical review andverification through on-site testing of grounding
methods for enhanced lightning resistance for
substations (Figure 4-4-1).
On the theme of substation protection frominverter controlled vehicles, a proposal was
made to eliminate unwanted trips of protection
relays caused by transient current generated
when pantographs re-make contact after contact loss. In addition, a further theoretical review

Fig. 4-4-2: Identifying the characteristics
of arc in basic research test

Annual Report 2015-2016

Railway Technical Research Institutewas conducted on control methods for feeding
voltage harmonics in conjunction with inverter
controlled vehicles. Research and development
was launched on the coordination of insulatorsin addressing ground faults in the boosting transformer feeding system and in simplifying related
facilities.

■ Current Collection Maintenance

The Current Collection Maintenance Lab conducts research and development on preservative
measures and overhead contact line materials for
current collection systems comprising overheadcontact lines and pantographs. Under the “R&D
toward the future of railways,” efforts were madeto develop basic technology for image-based contact line inspection. Under the “R&D of technology
for practical use,” review was made on the fatigue
resistance of steel wire strands of overhead contact lines while fouling categories for contact lines
were re-defined. Under the “basic research forrailways,” a fatigue mechanism of the contact wirematerial was determined while a technique wasdeveloped to estimate arc-discharged damage
to the pantograph that is caused when a frosted
contact wire loses contact.
In the estimation of arc-discharged damage tothe pantograph, basic research was conducted
to identify the characteristics of the arc (therelationships between its length, voltage andcurrent) to estimate its behavior (Figure 4-4-2).
In addition, the behavior of the arc during wire
contact loss was estimated by an electromagnetic field analysis. Furthermore, simulation ofarc-discharged damage to the pantograph was
conducted using a scale model of a pantographhead and sophisticated pantograph test equipment, the results of which indicated a possibility
to compare the effects of damage prevention
proposals.

■ Contact Line Structure

The Contact Line Structure Lab performs research and development to improve the current
collection process to prepare for higher speed,
reliability and seismic resistance. As part of “R&Dof technology for practical use research to develop “replacement standards for concrete poles”
was conducted. Typical degradation processes ofconcrete poles were identified through a surveyof concrete poles for damage, bending strengthand material analysis while a new process flow for
maintenance was proposed that includes strengthand material evaluations based on external harmful damage and alterations (Figure 4-4-3).
As a part of this effort, new items were developed to enable railway business operators
to easily implement the maintenance process

Fig. 4-4-3: Outline of the flow of concrete pole maintenance

Annual Report 2015-2016

41

Research and Development

flow including: a strength evaluation sheet whichshows the relationship between the peripheral
length of harmful alteration and the strength of
concrete pole; and a neutralization tester capableof accurately measuring the neutralization depthof concrete material.
Under the project “methods for setting the wiretension and deviation of overhead contact line,”
the impact that various types of tensioners canhave on current collection performance was clarified and appropriate use was suggested for all
types of tensioners based on their characteristics.
In another project entitled “identification oftemperature rise and wear mechanisms of acurrent collection component,” the cause forstepped wear of carbon composite contact strips
was clarified based on the graphitization degreeof the strip material and preventive measures
were proposed. In the research “evaluation of the
behavior of overhead contact line during earthquake,” a coupled analysis of the contact line andrailway structure was conducted to evaluate thecontact line’s seismic performance. Guidelines
were proposed for improvement of the contact
line.

5

Track Technology Division

The Track Technology Division consists offour laboratories, namely, Track Structures andComponents, Track Structures and Geotechnology,
Track Geometry and Maintenance, and Rail
Welding Labs. They are in charge of research anddevelopment on “safety improvement,” “speeding up”, “making maintenance more efficient andFig. 4-5-1: Proposed corrosion protection methods for rails

42

lower cost” and “reduction of noise and vibration” with respect to the track and its structure. In
FY2015, the research and development centeredon improved maintenance of rails, ballasted track
and ballastless track.

■ Track Structures and Components

The Track Structures and Components Lab
performs research and development of track components such as rails and rail fastening systems
that form tracks, turnouts, expansion joints andcontinuous welded rail.
Corrosion protection methods were proposed
for rails laid in corrosive environments such as
in tunnels: to select highly effective corrosion
protection measures;, to evaluate durability under
repeated wheel loads; and to mitigate damage tothe coating by rail fasteners (Figure 4-5-1).
To study “speed limitation measures based on
track conditions with rail failure,” the influence of
track irregularities, curve radius and speed onrunning safety were evaluated by simulating a
train running over a rail gap. Also, in the “development of a running simulator with consideration for
turnouts,” a running test was conducted using a
motor car to evaluate the behavior of the car running over set-off equipment and the force acting
on the track components.

■ Track Structures and Geotechnology

The Track Structures and Geotechnology Lab
conducts research and development on directly
fastened and ballasted track, roadbeds of new
and existing lines, embankment materials andmanagement, noise and vibration countermeasures, and the reuse of building and industry
by-products.
A new, low cost structure with a thinner concreteFig. 4-5-2: Method for filling gaps in slab filling layers

Annual Report 2015-2016

Railway Technical Research Institute

bed was developed as part of the “development of
low cost directly fastened tracks with resilient ties”
initiative. The performance of the new structure
was verified in a loading test.
In the “development of a method for evaluating the condition of slab filling layers basedon onboard-measured data and related repair
methods,” a method for filling gaps in slab filling
layers using high-fluidity cement asphalt grout,so called “High-fluidity CA milk” in Japan, (Figure
4-5-2) was developed and its effectiveness wasverified in an on-site test.
Ballast migration was reproduced in a loading
test using an exciter with variable loading direction and a low cost prevention method using
biodegradable polymer was developed. These
efforts were part of the “development of rational
ballasted track structure for steep cant curves.”
A device capable of swiftly measuring thestiffness of track while running on track was developed in a project subsidized by the Ministryof Land, Infrastructure, Transport and Tourism in
its railway technology development scheme. An
evaluation was made of changes in the rigidity of
track bearing beds under repeated loading using
a full scale model.

■ Track Geometry and Maintenance

The Track Geometry and Maintenance Lab
conducts research and development on track
maintenance methods, systems and machines
to improve both train running safety and ride

comfort.
In a project subsidized by the Ministry ofLand, Infrastructure, Transport and Tourism in
its railway technology development scheme, a
track structure improvement planning system
for local railways was developed for tracks withwood sleepers by considering safety parameterswhich are evaluated for each curve type. These
parameters include gauge-widening derailment,
spike failure and lateral shift of the track panel.
Based on the results, conversion to pre-stressed
concrete sleepers can be prioritized and a conversion plan prepared (Figure 4-5-3).
To help understand the mechanism of rail corrugations, a vehicle running simulation model wasdeveloped based on a track excitation model capable of reproducing varying degrees of rigidity of
track bearing beds with directly fastened sleepers
and the dynamic behavior of a multi-body vehicle.
Simulation model results confirmed that the useof low elastic track pads and the smoothing of
inner rail corrugation are effective in preventing
the generation of outer rail corrugations.

■ Rail Welding

The Rail Welding Lab conducts research anddevelopment on rail welding technologies, rail
head repair welding technologies, and nondestructive inspection technologies for rail andrail welds.
Thermite weld internal defect generation
mechanisms were identified by understanding

Fig. 4-5-3: Planning support system for conversion to prestressed concrete sleeper

Annual Report 2015-201643

Research and Development

how the thermite weld solidifies in a temperature
measuring test and in a numerical analysis using
a solidification analysis model. Further research
examined the wider application of thermite welding as a rail head repair method by proposing
the conditions for using the repair method forhead hardened rails. Test pieces were produced,
subjected to various solvent and forced air coolingand then examined for hardness and structure
to determine their potential as a possible repair
technique.

6

Disaster Prevention Technology
Division

The Disaster Prevention Technology Divisionconsists of three laboratories, namely, theMeteorological Disaster Prevention, Geo-hazard
and Risk Mitigation, and Geology Labs, which
are responsible for research and development,
consulting work, and contract work concerning
mitigation of natural disasters caused by rain,
wind, and snow, surveying and evaluation technologies for ground vibrations caused by therunning of trains.
In FY2015, efforts were made to advance the“realization of practical applications for a meteorological disaster hazard mapping system”
to produce practical applications of the fruits of
the laboratory’s activities gained thus far underthe “Research and development for the futureof railways.” Also, two new projects were initiated under the “sophistication of railway disasterprevention and mitigation technologies,” namely
the mitigation measures for disasters caused by
local meteorological phenomena such as wind
gusts and mitigation technologies for disasters
caused by heavy rainfall of short duration.

■ Meteorological Disaster Prevention

The Meteorological Disaster Prevention Lab
conducts research and development activities on
methods for determining weather conditions totake meteorological disaster countermeasures,and on methods for disaster risk evaluation.
The laboratory continued to advance the correlation analysis of precipitation intensity obtainedby weather radar and by ground observation
measurements, and the sophistication of snowfall
intensity estimation techniques. In addition, anevaluation was made of the space-time representation of wind velocity and wind direction obtainedby an anemometer on flat ground (category I – IIsurface roughness). Then a model was developed to estimate the wind direction and velocity
at locations up to 10 km away based on the winddirection and velocity at one point (Figure 4-6-1).
On the mitigation of wind gust disasters, anevaluation was made on the possibility of detecting gusts using data obtained by anemometers
and by analyzing wind data at locations near toprevious gusts. A project was also launched todevelop a gust detection method using weather
radar data. Also, as part of the research on disaster risk evaluation, a basic experiment was
conducted to develop methods of evaluating
damage by flying objects caused by tornadoes.
Based only on Japan Meteorological Agency’s
AMeDAS data two models were developed aspart of the research to help mitigate slope disasters caused by avalanches or snowmelt water inthe snowmelt seasons: a snow properties model
which estimates snow depth and snow density;and a snow melt model which estimates outflow
from the bottom of the snowpack on slopes.

Fig. 4-6-1: Example of 2-location, wind-velocity-difference model

44

Annual Report 2015-2016

Railway Technical Research Institute■ Geo-hazard and Risk Mitigation

The Geo-hazard and Risk Mitigation Lab conducts research and development for preventing
or mitigating slope disasters and river disasters.
To assist slope management during the snowmelt
period, we developed a method that can evaluateslope stability based on calculations of a parameter (effective snowmelt) that takes into accountthe impact of snowmelt and rainfall (Figure 4-6-2).
To help restore cracked embankments causedby an earthquake, we presented analytical results to demonstrate that the rainfall durabilityof a cracked embankment could be restored toits previous level by backfilling the cracks. We
developed an injection method as a countermeasure for the roadbed caving problem on the backside of abutments, and developed the relationshipbetween the viscosity of grout and the void-filledarea in the case of injecting grout into an embankment based on gravel.
In research to reinforce masonry walls withharmful deformations, a model experiment was
conducted to obtain essential coefficients fordeveloping a reinforcement method. And, in an
attempt to determine the destabilization mechanism of bridges by scouring in swollen rivers, ahydraulic model experiment was conducted tounderstand changes of water pressure and otherparameters in the ground with ongoing scouring.

■ Geology

The Geology Lab conducts research and development on large-scale slope disaster evaluation
methods, evaluation of geological factors concerning deformation of tunnels, prediction of thequality of water leached from waste/surplus soil,

basic studies on the impact of volcanic disasters
on railways, and ground vibration phenomena
clarification and prediction methods.
On large-scale slope disaster evaluation
methods, the topographic and geological characteristics of collapsed slopes were studied basedon the findings of site inspection, aerial survey
data, etc, and rainfall records were analyzed forany relationship with disasters (conducted aspart of the Cabinet Office’s Strategic Innovation
Promotion Program). Geological factors for tunnel
deformation were studied in a rock laboratory test
and by numerical analysis to develop a proposed
inspection plan for deformation due to plasticpressure.
In the project to predict the quality of waterleached from waste/surplus soil, the validity ofa model developed in the previous fiscal year
was verified in experiments and calculations. On
the topic of the impact of volcanic disasters on
railways, the following were clarified: situations
anticipated for railways following volcanic eruptions; and related subjects that must be studied
further.
To compare results of different modeling methods for analyzing the ground vibration problem on
structures near railway lines, different analyticalmodels were tried on the same rigid-frame viaduct. Numerical analysis found that the frequency
characteristics of the response acceleration are
different between dynamic components and static
components of axle load.

Fig. 4-6-2: Application example of slope stability
evaluation method

Annual Report 2015-201645

Research and Development

7

Signalling and Transport Information
Technology Division

The Signalling and Transport Information
Technology Division consists of five laboratories, namely, Signalling Systems, Train Control
Systems, Telecommunications and Networking,Transport Operation Systems, and Transport
Planning and Marketing Labs. They performresearch and development, consulting and contract work related to developing and improving
signalling and communication systems, clarifying
phenomena, evaluating technologies, increasing
the efficiency of train and traffic operation andenhancing the convenience of passengers. The
experts from this Division also participate actively
in international standard development and activities of academic societies.

■ Signalling Systems

The Signalling Systems Lab works to develop
and improve signalling systems, clarify causes ofmalfunctions, apply image processing technologies, and evaluate the service life of signalling
equipment. With the aim of saving labor requiredfor visual inspection of obstruction warning
signals, an inspection system consisting of an
obstruction warning signal fitted with near infrared
LEDs that emit invisible light and an onboard
camera was developed (Figure 4-7-1). It was
found in a long-term, on-site test that the system’s
inspection accuracy is unchanged regardless ofthe season or time.
A reference model for train protection systems

was developed to provide a means of ensuring
security for railway signaling software. The project
was conducted as part of the effort to develop
formal methods that describe specifications
based on mathematics and logic. To enhance thesafety of level crossings, a prototype system forcontrolling level crossings primarily via onboard
equipment was developed and the system’s following functions were tested: issuing commands
via onboard equipment to close a level crossing;and controlling speed by a protective speed profile
for a level crossing after detection of an obstacle.

■ Train Control Systems

By using information communication technology, the Train Control Systems Lab worked on
future train operation systems that offer flexible
and safe train services, evaluated safety andreliability of signaling systems, and provided
design support for signaling systems. On future
train operation systems, basic specifications fora system that controls individual trains and theirroutes were developed. The system integrates
train operation and protection controls and performs real-time recalculation of station arrival anddeparture times and train performance curves.
A system combining an inertial sensor and atachometer generator was proposed to calculate
train lengths for radio based train control systems.
A prototype system that controls train routes
primarily via onboard equipment while not relying on the conventional interlocking device wasdeveloped for local railways (subsidized by the
Ministry of Land, Infrastructure, Transport andTourism in its railway technology development

Fig. 4-7-1: Obstruction warning signal inspection system

46

Annual Report 2015-2016

Railway Technical Research Institutescheme). A running test conducted on the RTRI’s
test track verified that the system is capableof controlling trains safely even in non-normal
situations.

■ Telecommunications and Networking

The Telecommunications and Networking Lab
works on telecommunication technologies suchas wireless and wired communication and sensor networks, researches mathematical analysis
and prediction methods on structure monitoringdata to support maintenance work, and develops
prediction and evaluation methods for electromagnetic environments on electric railways.
On telecommunication technologies, anexperiment was conducted to examine the possibility of adopting the 920 MHz Wi-SUN network
technology for facilities monitoring. Its practical
performance was verified in the experiment in accordance with the theme offered by the National
Institute of Information and Communications
Technology for open participation (Figure 4-7-2).
Also, software that predicts train radio call quality
by simulation and supports radio link design wasdeveloped.
A method for analyzing the relationship between monitoring data sent from multiple sensors
and predicting changes in facilities status wasdeveloped. In work on the electromagnetic environment, a system that simulates voltage andcurrent applied to communication facilities in alightning surge was developed, and a method was

proposed for quantitatively evaluating the effect ofprotection measures such as changing grounding
methods and installing a surge protective device.

■ Transport Operation Systems

The Transport Operation System Lab develops
methods to improve the efficiency and convenience of transport planning and traffic control. A
train performance calculation function for energy
consumption evaluation was included in the system for predicting energy consumption from train
operations. It was confirmed that the calculated
power supply generally agrees with measured
data. (The study was subsidized by the Ministryof Land, Infrastructure, Transport and Tourism
in its railway technology development scheme.)
In developing train operation simulators to accommodate the sophistication of train control,
calculations were made possible to accommodate
moving block and prediction-based control. On
railway traffic operation arrangement with delays
caused by speed control, a cancellation method
proposed by the laboratory proved to be effective
in restoring train operation to normal within a shortperiod of time. Additionally, the interface for the
train performance calculation system SPEEDY
was upgraded.

■ Transport Planning and Marketing

The Transport Planning and Marketing Lab conducts research and development programs related
to the analysis of passengers’ decision-making

Fig. 4-7-2: Verification test of wireless sensor network

Annual Report 2015-201647

Research and Development

structures such as transport mode choice behavior and route choice behavior, and quantitativeevaluations of services in stations. In the project“methods for predicting passenger traffic taking
into consideration appealing features of andaround the station,” a method was developed thatquantitatively evaluates the change in a station’s
appeal due to renewals around the station as wellas the development of commercial operations andfacilities improvement at the station. A method
to predict passenger traffic was also developed.
In the project “methods for flexibly arranging
reserved and non-reserved seats in higher classtrains,” two models were developed: one for estimating potential demand not shown in demand
data; and another for estimating passengers’ best
choice in congestion or other unexpected situations. In further developments, two other items
were developed: a passenger traffic simulator;
and a seat type planning and allocation system.
In the project “methods for measuring windfall
benefits of railway investment,” a quantitativeevaluation was made using the stated choicemethod on windfall benefits of an investment inmaintaining or improving limited express services
for those who live near a station in a local city but
typically do not use limited express trains. Thisis a concept that has not been considered in thepast in railway investment processes.

8

Materials Technology Division

The Materials Technology Division consistsof five laboratories, namely, Concrete Materials,
Vibration-isolating Materials, Lubricating
Materials, Frictional Materials, and Applied
Superconductivity Labs. They are responsible
for research and development, consulting workand contract-based work concerning railway
materials, and also for searching, introducing,researching and evaluating the environmental
impacts of various new materials. With the aimof adopting flame-retardant magnesium alloy
for body structures, structural analyses wereconducted to propose members with optimally48

shaped cross sections while a basic study was
conducted on laser welding.

■ Concrete Materials

The Concrete Materials Lab works on methods
for evaluating technologies related to the maintenance and building of concrete structures andthe development of new materials. The resultsof the Lab’s research included determining therelationship between the composition and basic
properties of low-environmental-load geopolymer
concrete. Research on the deterioration of concrete resulted in determining the mechanism ofsulphate expansion and showed that expansion
can be triggered even with small amounts ofsulfate, Other studies on the mechanism of concrete structure degradation caused by chemical
reactions demonstrated that the quality of surface
layers is strongly affected by curing conditions
and that moisture penetration causes reinforcing
bars to corrode about 10 times faster in the neutralization zone. Additionally, Spray Test Method
A was developed as a simple non-destructive
inspection method to determine surface quality
by visual observation of water absorption.

■ Vibration-isolating Materials

The Vibration-isolating Materials Lab conducts
research and development of new materials related to rubber and resin/plastic used in railways
and investigates evaluation methods for theirperformance and durability. One research projecton materials for vehicles concerned the plastic
window glass used for vehicle weight reduction
purposes, whereby a method was developed toevaluate the yellow discoloration of polycarbonate
using a quick and non-destructive way to measure the color change. In an attempt to adopt
piezoelectric rubber, known for its flexibility andmoldability, for sensors of foreign matter on sliding
doors, a material durability test was conducted
and the results showed the rubber has the required durability. Also, as part of data gathering
for the development of a life cycle cost (LCC)
method to evaluate repainting of steel structuresin a corrosive environment, the criteria for rusting
was refined while the knowledge about the natureof rusting was developed further.

Annual Report 2015-2016

Railway Technical Research Institute

Table 4-8-1: Revised criteria values for control (Only the revised items are shown.)

Criteria values
Control item
Oil depletion rate
(formerly oil separation rate)

Dropping point

Iron content

Traction motor
bearing

15.0% or less (Alert level: 6%)
Lithium complex soap:
215 ºC or higher (Alert level: 240 ºC)
Other than the above:+/-20 ºC (variation range)
0.5% or less

■ Lubricating Materials

The Lubricating Materials Lab conducts research and development of bearings and othermachine components that play a part in the running of vehicles and of lubricant oils and greases
that maintain their operation. As a result of research into the degradation of grease for vehicles,
especially for axle and traction motor bearings,
the criteria values for control established by JNR
and existing guidelines on evaluating degradation, were revised. These revisions (see Table
4-8-1) are based on the current knowledge ofgrease degradation mechanism and the resultsof degradation analysis of grease used in actual
vehicles. To investigate fretting wear between theaxle bearing inner ring and the backing ring, abench test was conducted where contact pressure between the components was measured.
This work resulted in a hard film coating being
suggested as a probable resolution for the wear.
With the aim of further understanding the seizureof gear unit bearings, a test machine capable ofrunning pinion bearings under varying load andat varying speed was developed.

■ Frictional Materials

TThe Frictional Materials Lab conducts researchand development to improve the functionality andperformance of railway components involved intribology phenomena, including friction, wear andAnnual Report 2015-2016

Axle bearing

1.0% or lessHandling of fretting wear is
specified separately.

rolling contact fatigue, and clarifies the mechanism of damage caused by these phenomena Railresearch activities included investigating the useof a portable X-ray stress measuring device forthe proper control of rail axial force. It was foundthat the measurement accuracy of this device
can be improved by mechanically polishing atarget area for the measurement. In a research
project to reduce the wear of a wheel flange,
resulted in solid lubricants were prototyped andtheir wear performances were evaluated in wear
tests. Basic tests of the wheel and rail interface
were conducted to monitor the behavior of thetangential force coefficient under test conditions
with longitudinal and lateral tangential forces
applied. Research of carbon composite contact
strips included evaluating the bolt fastening axial
force as a function of the thickness of the contact
strip to determine wear limits.

■ Applied Superconductivity

The Applied Superconductivity Lab works on
the application of high-temperature superconducting material to railways, carrying out development
projects including superconducting feeder cables
and superconducting magnets. Superconducting
feeder cable fabricated by the laboratory was laid
at a substation on Izuhakone Railway’s Sunzu
Line and power was transmitted via the cables totrains. This was the first trial of its kind conducted49Research and Development

development to understand the phenomena associated with dynamic behavior occurring in railway
systems and various deterioration consequencesof these phenomena, and to propose appropriate,
specific resolutions. In FY2015, the laboratory
worked on the development of a method for
detecting stepped wear of contact strips of apantograph and a method for analyzing contact
behavior between car bodies and ground facilities
during earthquakes. These and other projects aredescribed below.
Fig. 4-8-1: Train running test using superconducting feeder cable

on a commercial line in the world (Figure 4-8-1).
In research to develop high-temperature superconducting materials, small superconducting
magnets were fabricated using rare-earth bulk
material and attempts were made to make themagnetic field homogeneous using shim coils thatwere fabricated. To investigate possible applications of the new MgB2 material, a bulk versionof the material was made to evaluate the current
conduction characteristics of a wire version in amagnetic field. In addition, efforts were made to
develop elements for a superconducting quantum
interference device to detect weak magnetic
fields.
This work was supported by the Ministry ofLand, Infrastructure, Transport and Tourism of theGovernment of Japan, and the Japan Science andTechnology Agency (JST), Strategic Promotion of
Innovative Research and Development, Advanced
Low Carbon Reduction Technology, Grant-in-Aid
for Scientific Research (A) from the Japan Society
for the Promotion of Science (JSPS) under grantNo. 16H01860.

■ Vehicle Mechanics

The Vehicle Mechanics Lab conducts researchand development related to the safe runningof vehicles. To reduce the risk of derailment,
the development of a new type of bogie with amechanism for controlling wheel load reduction
was continued. A running performance test of the
prototype bogies was planned at the Mihara Test
Center of Mitsubishi Heavy Industries in 2016.
Hence, a coupler was developed for the test inwhich the narrow gauge test vehicle will be pulled
by a standard gauge towing vehicle on a 3-rail
track.
In order to better understand the dynamic behavior of a vehicle when its wheels are in contact
with the guard angle, a test vehicle running test
was conducted on RTRI’s test track. In addition, a
new research project to develop a wheel lift measuring method and a next-generation wheel-rail
contact force measurement system was initiatedto establish new running safety evaluation procedures. On the development of vehicle parts
resistant to derailment during earthquakes, acompact crushable lateral displacement stopper
was developed as a practical proposal.

■ Current Collection

9

Railway Dynamics Division

The Railway Dynamics Division consistsof five laboratories, i.e., Vehicle Mechanics,
Current Collection, Track Dynamics, Structural
Mechanics, and Computational Mechanics Labs.
These laboratories are in charge of research and50

The Current Collection Lab conducts studies
on prediction methods of dynamic behavior of thepantograph/catenary system, condition monitoring methods for the catenary, and developmentof high-speed pantographs. To better predict
dynamic behavior of the pantograph/catenary
system, the three-dimensional dynamic pantograph/catenary simulator was improved to enablecalculation of static geometry of catenaries incurves. On condition monitoring of the catenary, aAnnual Report 2015-2016

Railway Technical Research Institutemethod that detects step-shaped wear of contact
strips of a pantograph based on measurementsof strain in the pull-off arms and a power saving
digital telemeter suitable for this system weredeveloped (Figure 4-9-1).
For the development of high-speed pantographs, a newly developed pantograph HILS
test confirmed that active control can halve lowfrequency contact force fluctuation. It was foundthat aerodynamic noise can be reduced by anappropriate arrangement of the pantograph head
and the articulated frame which affects aerodynamic interference between them.

■ Track Dynamics

The Track Dynamics Lab conducts researchand development activities on ballasted track
deterioration, rail damage, wheel/rail adhesion
and lubrication. As part of research on ballasted
track deterioration, a repeated loading test using
a life-size ballasted track model and numericalanalysis simulating the loading test revealed
that impact load can be reduced substantially by
adopting improved resilient sleepers. Motor car
running tests and simulations using a discretemodel were conducted to evaluate whether the
impact load generated at rail joints has any effectin causing ballast settlement. Also, efforts weremade to improve the estimation accuracy of themeasurement of axial force of the rail.
In researching damage to rails, on-site investigations and laboratory tests were conductedon the white layer. Specifically, the relationship between the thickness of the white layer
and the hardness of rail top surface as well as

Fig. 4-9-1: Contact strip stepped wear detection sensor
and its dedicated telemeter.

Annual Report 2015-2016

micro-cracking originating from the white layer
were investigated. On wheel/rail adhesion andlubrication, a vehicle running test was conducted
to clarify the effect that substances between thewheel and rail can have on wheel/rail adhesion
behavior.

■ Structural Mechanics

The Structural Mechanics Lab builds advanced
simulation and analysis technologies, and measurement technologies. It uses these technologies
to conduct research to improve running safety andto advance the design and maintenance strategies for railway structures.
In simulating vehicle running performance
during earthquakes, an algorithm capable of efficiently calculating the contact force between arunning train and ground facilities was proposed
while an analytical tool capable of quantitatively
evaluating the behavior of vehicles before andafter derailment was developed (Figure 4-9-2).
For remote non-contact evaluation of railway
bridges, a method was proposed to efficiently
estimate the natural frequencies of cable stayed
bridge cables and continuous rigid-frame viaducts
using a long-distance U-Doppler system. Alsoan unmanned aerial vehicle (UAV) for structuralinspection was developed to run under the structure surface by caterpillar tread and inspect areas
with damage or harmful alteration. On evaluation of the remaining life of prestressed concrete
sleepers, a remaining life evaluation method was
proposed based on examination results of 165
aged prestressed concrete sleepers.

Fig. 4-9-2: Analysis of contact between vehicle
and ground facilities

51

Research and Development■ Computational Mechanics

The Computational Mechanics Lab has constructed a wheel-rail rolling contact analysis
method based on finite element method to clarify
the long-term deterioration phenomena of wheels
and rails. A bogie model capable of simulating
the wheelset’s lateral movement and yawing wasdeveloped to enable more realistic analysis.
On the development of an air flow simulator,
a RANS/LES hybrid analysis method (DES) of
turbulence calculation based on the Reynolds
averaged model (RANS) and turbulence calculation by spatial averaging (LES) was introducedwith the aim of efficiently conducting analysis of
the turbulence in a flow field around the train set
A common platform was built to allow any
railway simulators to work independently. Also,on the optimization of carbody structures, a press
molded structure for the side body structure was
optimized by using the results of stress analysis
of a whole single-vehicle structure model.

10

Environmental Engineering
Division

The Environmental Engineering Division consists of three laboratories, namely, the Vehicle
Aerodynamics, Heat and Air Flow Analysis, andNoise Analysis Labs. They are responsible forresearch and development, consulting, and contract work concerning wayside environments andFig. 4-10-1: Numerical simulation of turbulence around a vehicle
on an embankment (Visualization of vortex structure)52

aerodynamic phenomena. In FY2015, the Division
worked on subjects related to environmental impact and safety of railways including “reduction in
wayside environmental impact caused by faster
Shinkansen,” which is a part of one of the 4 major
challenges,Research and development for the
future of railways.

■ Vehicle Aerodynamics

The Vehicle Aerodynamics Lab works on problems related to the aerodynamic characteristicsof railway vehicles. A number of projects wereconducted on vehicle aerodynamic characteristics
in cross winds: clarification of the aerodynamic
force coefficient for trains on coastal half-bankand half-cut structures; evaluation of the reduction in aerodynamic force by windbreak fences;and evaluation of the effect of a running vehicle
using a commuter type vehicle model. Numericalsimulations were conducted to reproduce a crosswind tunnel test (Figure 4-10-1).
To examine the aerodynamic forces acting on
a vehicle due to a turbulence field, a wind tunnel
test was conducted to measure lateral flow velocity under the vehicle floor as well as air resistancecaused by an irregular underfloor profile.
The Lab has air flow simulators capable ofhandling real train set configurations and thiscapability was improved by: a program updated
to accommodate GPU (Graphics ProcessingUnit); the introduction of a Reynolds averaged
turbulence model; and the introduction of DES(Detached Eddy Simulation), a hybrid of Reynolds
averaged turbulence model and LES (Large Eddy
Simulation) turbulence model. It was found thatthese methods produce reliable calculations.

Fig. 4-10-2: Tunnel fire experiment device

Annual Report 2015-2016

Railway Technical Research Institute■ Heat and Air Flow Analysis

The Heat and Air Flow Analysis Lab works
on aerodynamic phenomena related to railways
including: pressure waves and pressure variation
caused by trains traveling through tunnels; thethermal environment inside tunnels; and hot-gas
flow in a tunnel fire.
In a project involving micro-pressure waves,the Lab conducted quantitative evaluations ofproposed measures to accommodate further
increases in Shinkansen speed. The proposed
measures are concerned with compression wave
propagation and micro-pressure wave radiation.
On the thermal environment inside tunnels, anumerical simulation model of heat transfer tothe tunnel wall was improved for higher accuracy
based on results of theoretical analyses andmodel experiments. Comparison with results ofa long-term on-site test found that quantitative
analysis of the cooling capacity of undergroundstations is important in predicting the tunnel
temperature of underground railways. For theprediction of the flow of hot gases in a tunnel fire,a model experiment was conducted whereby thetemperature, propagation speed and temperature
distribution of the flow of hot gases were examined (Figure 4-10-2). The test was conducted toverify the results of numerical calculations basedon a general-purpose CFD code.

grinding intervals could be extended.
On aerodynamic noise, a wind tunnel test was
carried out in order to investigate the contributions of specific components of the bogie to total
aerodynamic noise generated around a bogie. It
was found that, apart from wheels and axles, traction motors, brake units and other components
within the bogie have moderate contributions
to the total noise. In the work on low frequency
noise in open sections, scale model experiments
using a train model launcher and full-scale fieldtests were carried out. Through the field tests, it
was found that aerodynamic noise in the range of
20 - 50 Hz has a greater contribution than otherranges above 5 Hz. For research related to noisepropagation, in order to investigate the acoustic
behaviors at a cut section along a Shinkansenline, scale model experiments were made andthe reflection and diffraction of sound on the slope
in the section were examined. Then, based on
the results obtained in the experiment, a noise
prediction model was developed.

■ Noise Analysis

The Noise Analysis Lab works to clarify andpredict railway wayside noise and to develop
countermeasures. To examine wheel/rail noiseand other structure borne noise, the impact noisedue to rail joints and high frequency noise above
10 kHz in curve sections were examined. Also,
the relationship between the geometries of thelocalized wear of wheel treads and the resulting bridge noise was investigated. The effect oftread wear on wayside noise was estimated anda method to estimate the depth of the localized
tread wear based on the vibration of a viaduct
was developed (Figure 4-10-3).
In order to understand suitable rail grinding intervals, rail roughness, rail vibration and waysidenoise were measured for long term evaluation
after rail grinding. Based on the measurementsby track inspection cars, it was found that rail
Annual Report 2015-2016

Fig. 4-10-3: Relationship between the vibrationof a viaduct and localized wear of a wheel

53

Research and Development

11

Human Science Division

The Human Science Division consists offour laboratories, namely, Safety Psychology,
Ergonomics, Safety Analysis, and Biotechnology
Labs, which are responsible for research anddevelopment on human factors to contribute to
the improvement of the safety and comfort ofrailways. In FY2015, the Division carried out
research on the prevention of human error, education and training, train operator support, skills
for coping with accidents and malfunctions, in-car
comfort, and support for safety management, andconvenience of railway station. It also provided
technical guidance for train operation aptitude
tests and supported safety activities of railway
companies.

■ Safety Psychology

The Safety Psychology Lab develops training
methods to prevent human error. It also provides
technical guidance for train operation aptitude
tests.
On the prevention of human errors, tasks designed to measure decision-making skills weredrafted to help develop education methods for

improving these skills. And, to develop education
methods for preventing errors in communication,a survey and experiment were conducted on theoccurrence of errors. In a project to develop
education and other methods for preventing levelcrossing accidents involving elderly automobile
drivers, a survey and experiment were conducted
to understand the participants’ knowledge about
correct ways to cope with emergencies and otherissues at a level crossing.
The Lab provided technical guidance for train
operation aptitude tests by providing lectures to
353 individuals from private railroad operatorsand district transport bureaus of the Ministry ofLand, Infrastructure, Transport and Tourism.

■ Ergonomics

The Ergonomics Lab conducts research anddevelopment on driver monitoring methods, vehicle safety enhancement in accidents, improved
information provision to passengers and improvement in in-car comfort.
On driver monitoring methods, a driving simulation experiment was conducted to measure brain
and other physiological activities. In researchingvehicle safety enhancement in accidents, theconditions for passengers in longitudinal seats tosustain severe injuries in accidents were identified

Fig. 4-11-1: Entire scope of in-car thermal comfort prediction model

54

Annual Report 2015-2016

Railway Technical Research Institutebased on the results of a sled impact test andsimulation analysis.
In work to provide information to passengers,
education programs were proposed that aredesigned to improve skills to be more flexible inproviding instructions to passengers when train
services are disrupted. Also, in order to improvethe visibility of blocks for Tactile Walking Surface
Indicators (TWSI) that guide visually impaired persons, the requirements for a continuous adjoining
band that is laid on both sides of the TWSIs wereclarified.
To improve in-car comfort, a thermal comfort
prediction model applicable to the non-steadythermal environment of railway vehicles was
proposed based on the results of thermal sensation experiments (Figure 4-11-1). In an effort tomonitor unpleasant vibration of running trains,tracks that had undergone maintenance wereidentified as having improved ride quality levels
and the Unified data-relevant-ride-comfort indication system was upgraded.

■ Safety Analysis

The Safety Analysis Lab helps railway companies evaluate railway risk and improve safety.
As a tool to efficiently use the RTRI Human
Factor Analysis Method designed to analyze
underlying factors for human errors, new procedures were proposed for facilitating improvementin operation and organization based on reports
of potential incidents and other risk-related
information and logical analysis of human factors (Figure 4-11-2). To help railway business
operators implement safety enhancement activities, technical guidance was provided on the RTRI
Human Factor Analysis Method and the Hearing
Investigation techniques. Also research projects
have been conducted on the Safety Climate in
the Work Site.

Fig. 4-11-2: Human Factor Analysis Method
using risk-related informationcrew workload.
To help evaluate the health impact of magnetic
fields, cultured mammalian nerve cells werestudied to monitor their reaction to stimulationof magnetic fields while their thresholds werestudied. To help prevent mold, a method was proposed for evaluating mold prevention measuresthat uses surface water content as a parameterfor plasterboard, one of widely used interior materials. On the utilization of fragrance, a survey
was conducted on the impact of fragrances thatcause cooling sensations for improvement of theheat environment in railway stations in summer.
In dealing with collision of trains and wild
animals, investigations were carried out to understand the behavior patterns of deer aroundrailway facilities. Several types of sound were
found effective in scaring away deer when thesound was transmitted from the front of a vehicle
in operation.

■ Biotechnology

The Biotechnology Lab works on the evaluationof short-term health impacts of magnetic fields tohelp ensure the safety of magnetic fields emitted
from railway systems, mold prevention measuresand utilization of fragrance to improve comfort,
and measures to reduce problems with wild
animals to ensure safe operation and suppress
Annual Report 2015-2016

55

Research and Development

12

Maglev Systems Technology
Division

The Maglev Systems Technology Divisionconsists of two laboratories, namely theElectromagnetic Systems Laboratory and
Cryogenic Systems Laboratory, and the
Yamanashi Maglev Test Center, which are responsible for basic research on superconducting
magnetically-levitated transportation (Maglev)
systems. They also conduct research on theapplication of technologies created by researchand development of Maglev systems (such as
superconducting technology, cryogenic technology, and linear motor technology) to conventional
railways and related contract work. Additionally,
they conduct vehicle running tests and manage
the assets of the Yamanashi Maglev Test Centerand other related operations.
As part of basic research on Maglev systems,
the Division has worked on vehicle dynamics,
made efforts to reduce the cost of introducing newtechnologies to superconducting coils and groundcoils, and researched equipment diagnosis andmaintenance technologies for commercial lines.
As part of research on application to conventional
railways, the Division has developed high-speed
linear induction motor (LIM) type eddy-current
rail brakes, flywheel energy storage systems forrailways using superconducting magnetic bearings, and non-contact power supply technologies.
At the Yamanashi Maglev Test Center, the total
distance traveled by the Maglev vehicles in thelong-term durability tests on the entire 42.8-km
track in the Japanese fiscal year of 2015 was344,422 km (about 4 times the greatest total distance recorded on the priority section) in a total of
247 testing days. These achievements represent
the greatest number of vehicle-running days andthe greatest total distance traveled by the Maglev
vehicles in any single year. With the contributionof this annual record, the cumulative Maglev
vehicle running distance on the entire 42.8-km
track exceeded 1.5 million km. On April 21, 2015,
the Maglev vehicle achieved a maximum speedof 603 km/h in a manned running test.

■ Electromagnetic Systems

The Electromagnetic Systems Lab conducts
vehicle dynamics analysis and ground coil evaluation of Maglev systems, develops linear induction
motor (LIM) type eddy-current rail brakes forhigh-speed trains and non-contact power supply
technologies for railway vehicles, and works onconventional railway vehicle magnetic field evaluation methods.
In anticipation of the adoption of rare-earth
high-temperature superconducting magnets on
Maglev vehicles, electromagnetic characteristics
were estimated for an environment with smaller
electric gaps, as part of the Maglev vehicle
dynamics initiative. This study led to the observation that lower ground coil current and power
consumption can be realized. In research on
ground coils, a non-contact insulation tester for
propulsion coils and cables was developed andits performance verified. Vibration characteristics
of propulsion system cables were identified inelectromagnetic vibration tests. Also, proposed
methods for extending the service life of groundcoils such as by repair were put to durability tests
using resin molds for ground coils as test pieces.
On the development of LIM-type eddy-current
rail brakes for high-speed trains, a small, lightweight armature that operates even during
power outages was designed and prototyped.
Subsequent roller tests showed that the prototype
was effective in shortening the braking distance(Figure 4-12-1).
For non-contact power supply technologies
for railway vehicles, calculations were madeincluding required power capacity for continuous
power feed to vehicles. It was found that thetwist of conductors is a contributing factor to
reduced efficiency of the power feed, an issue

Figure 4-12-1: Roller test rig for linear induction motor (LIM) typeeddy-current rail brakes

56

Annual Report 2015-2016

Railway Technical Research Instituteassociated with the lengthening of power feed
sections. And, in developing evaluation methods
for conventional railway vehicle magnetic fields,
an alternating magnetic field visualization device
was fabricated to enable efficient searches forcomplex alternating magnetic fields in vehicles.

■ Cryogenic Systems

The Cryogenic Systems Laboratory develops
high-temperature superconducting magnets forMaglev systems, and flywheel energy storage systems for railways using superconducting magnetic
bearings. On high-temperature superconducting
coils, a coil case resistant to 700 kA excitationstress was designed and fabricated based on
the results of numerical analysis and evaluationof mechanical vibration and eddy current heatgeneration characteristics, as well as related
sample testing. A full size high-temperature
superconducting coil capable of generating corresponding magnetomotive force was fabricatedusing rare-earth high-temperature superconducting wire. (The research was subsidized by the
Ministry of Land, Infrastructure, Transport andTourism in its railway technology development
scheme.)On flywheel energy storage systems, tests
were conducted on a test unit installed in a systemtest facility at a photovoltaic power plant (Figure
4-12-2) including: levitation and rotation tests on
the large-diameter flywheel with superconducting magnetic bearings; tests on related systems;
and non-normal performance tests in which therefrigerator was stopped by conditions such as
power outages. These tests proved that the unit
demonstrated stable levitation and rotation andthat the unit was appropriately designed for safe
operation. (The project was funded by the New
Energy and Industrial Technology Development
Organization (NEDO) and conducted jointly by
Kubotek Corporation, Furukawa Electric Co., Ltd.,
Mirapro Co., Ltd., the Public Enterprise Bureau
of Yamanashi Prefecture and RTRI.)
In other projects, it was found that: the current
design of superconducting magnetic bearing forthe heavy duty railway flywheel can be upgradedfor practical application; a proposed method for
estimating the internal temperature of resin using
heat flow sensors on the coil surface was foundAnnual Report 2015-2016

Fig. 4-12-2: Test unit for flywheel energy storage systemeffective as a diagnostic tool for ground coils; andthe communication range and reception rates
in the guideway were identified for low-powerconsumption Bluetooth Low Energy as a wirelesstool for interchange communication.

13

Center for Railway
Earthquake Engineering
Research

The Center for Railway Earthquake Engineering
Research consists of three laboratories,
namely, Seismic Data Analysis, Soil Dynamics
and Earthquake Engineering, and Structural
Dynamics and Response Control Labs, which
are responsible for earthquake-related researchand development, consulting work and contract
testing work.
The Earthquake Information Distribution
System was developed, and launched in June
2015. Under the system, information released
from the Japan Meteorological Agency and the
National Research Institute for Earth Science andDisaster Resilience after an earthquake is sent
to RTRI. Based on this information, RTRI swiftly
calculates the seismic ground motion (acceleration and seismic intensity) across Japan using
the Center’s ground database. The informationis then distributed on the Internet free of charge
to the subscribers to help them with repairs andrestoration of service.

57

Research and Development■ Seismic Data Analysis

The Seismic Data Analysis Lab undertakes
research and development to improve early
earthquake warning capabilities and its reliability,
to provide instantaneous predictions of tsunamis,
to estimate earthquake motion and damage withhigh precision and offer draft specifications/
regulations to achieve early restoration of railway
services.
To improve early earthquake warning capabilities, the laboratory produced and tested a
prototype seismograph that incorporates a new
P-wave based earthquake specification estimation

Fig. 4-13-1: Prototype seismograph and noise discrimination method

Figure 4-13-2: Deformation characteristics test methods

58

Annual Report 2015-2016

Railway Technical Research Institutealgorithm and a noise discrimination method. The
test found that the proposed algorithm runs in astable manner (Figure 4-13-1). Characteristics ofvibrations from construction/maintenance workthat may affect seismometers for early warning
were analyzed. Also a study of the behavior ofsea-bottom seismometers during strong earth
motions was started.
To help improve instantaneous predictions oftsunamis, a simulation was conducted to evaluate
the applicability of early tsunami height prediction
methods that are based on the characteristics oftsunami propagation with respect to earthquake
faults other than those related to major fault slips.
In a study to develop highly precise earthquake
motion estimation and regulations, it was foundthat the spatial change in earthquake response
measured around railway lines can be quantitatively evaluated with knowledge of relevant
underground structures.

■ Soil Dynamics and Earthquake
Engineering

The Soil Dynamics and Earthquake Engineering
Lab conducts a wide range of basic and appliedresearch and development on the ground behavior near to earthquakes from the basic propertiesof earthquake motion to its impact on the groundwhen an earthquake occurs. On projects that canbe immediately put to practical applications, thelaboratory has been working on the developmentof a seismic design method for railway structures
as well as on the development of economic countermeasures against liquefaction.
In the project on the ground behavior during
earthquakes, in an effort to establish more accurate methods for obtaining the deformation
characteristics of the soil for use in dynamic
response analysis, a laboratory soil test method
was proposed that is capable of evaluating moreaccurately the stiffness and hysteresis dampingof soil from low to high strains (Figure 4-13-2).

■ Structural Dynamics and Response
Control

Fig. 4-13-3: Evaluation graphs of damping constantsand develops sophisticated methods to evaluate
their behavior. It has conducted research anddevelopment of seismic design methods andseismic retrofitting work methods. To evaluate
the behavior of structures and vehicles, it has
measured the damping constants/coefficients ofabout 130 railway structures and produced graphsof their evaluations (Figure 4-13-3; subsidized by
the Ministry of Land, Infrastructure, Transport andTourism in its railway technology development
scheme). An evaluation was made on the relationship between the magnitude of the damping
constant and vehicle running safety. Based on
the results of these activities, a method was proposed whereby structures lacking good seismic
performance can be identified from among thosealong a specific railway line based on low marks
in damping constant.
On seismic design, research was conductedfocusing on input loss effect, one of phenomena
resulting from dynamic interaction between the
ground and structures. It was found that thefoundations restrain ground motion, which likely
dampens the seismic force applied to the structure on the foundations. Additionally, a method
for correcting design spectra with respect to that
damping effect was developed. This makes it
possible to provide rational designs especiallyfor structures with short periods.

The Structural Dynamics and Response
Control Lab works to determine the seismic behavior of structures, power poles, vehicles etc.

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Outline of Activities FY 2015

1 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, the60organization’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.

Annual Report 2015-2016

Railway Technical Research Institute2

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

Annual Report 2015-2016

R&D, the following three agendas are adopted as
the “Pillars of R&D” (Figure 2-1-1).

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 to social
trends○ Point to advanced R&D and the future ofrailways○ Leverage RTRI’s expertise in fields andareas 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
spin-off 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.

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Outline of Activities FY 2015

Figure 2-1-1(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,
sufficient resources should be mobilized so as
to meet the needs of the railway business andto ensure 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 ofrailway operators, leveraging RTRI’s specialist
facilities and analysis technology, and aiming
at practical application in actual fields of therailway 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.

62(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.

(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.

Annual Report 2015-2016

Railway Technical Research Institute

Figure 2-1-2- 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
lines and the global environment- Improvement of safety with a focus on humanfactors
Furthermore, research activities on Maglev
Systems should be conducted continuously with afocus on the application of superconductivity, linear motors, and other technologies to conventional
railways as a primary objective. Simultaneously,as part of the basic research programme, R&D
should be carried out for maintaining the technicalcapabilities needed for such activities.

(e) Facilities and equipment for researchand testing

facilities should be directly connected to R&D activities in fields where RTRI intends to introduce
innovative technologies. In addition, where theperformance of test facilities has declined overtime so that they no longer meet R&D needs,
they should be improved or renewed, in addition
to construction of new buildings for experiments.

(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 tocontribute 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.

Original facilities and equipment for researchshould be replaced where necessary; the selected

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63

Outline of Activities FY 2015(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.

(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 should64

be 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
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 “RailAnnual Report 2015-2016

Railway Technical Research Institute
Advisers.” 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
and intensify its partnerships with them, andalso boost educational activities on international
standards for the parties concerned and humanresource development activities.

(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.

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65

YEAR 2015-2016: April 1, 2015 - March 31, 2016
Copyright© 2016 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/

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Annual Report 2015-2016