Messages from Departments and Centers of NILIM

Towards effective use and appropriate maintenanceof the road stock —Initiatives under a new organization—
MORI Nozomu, Director
Road Department(Key words) Road, road traffic, road structure, stock, effective use, maintenance

1. New Organization
During the past period of more than half a century
since the beginning of full-scale road construction,
roads have played a role as the infrastructure
supporting social and economic activities centeredon automobiles while forming a quantitative stock.
But, the environment surrounding roads has beengreatly changed and will continue to change. Thischange means that the stock which has been formed
should be used more effectively and the stock shouldbe appropriately maintained.
For road users, problems remain; namely roadtraffic accidents and congestion. Taking traffic
accidents as an example, 4,373 fatalities occurred in2013, which is 1/4 of the record-setting 16,765
fatalities which occurred in 1970, but fatalities ofpedestrians and cyclists has risen from about 38% of
all road traffic accident fatalities in 1993, which it wasat its lowest level, to about 50% in 2013. Annual
congestion loss time is about 5 billion hours, or about
40 hours per person. There are many problems related
to the use of the stock which has been formed,
requiring that the stock be used more effectively, by
improving road space or effectively use networks andso on.
Regarding the appropriate maintenance of the stock
which has been formed, problems with technology
methods, standards, systems, technological capability
etc. for the maintenance of aged and deteriorated
structures have been pointed out, requiring thattechnology methods be established and supportsystems be constructed quickly. The Great East Japan
Earthquake showed the importance of opening roads
and of overlapping and alternate networks. To
improve wide area disaster prevention, it is necessary
to manage roads so that they can function as networks
immediately after a natural disaster.
Road related departments and centers of the NILIM
have worked in cooperation with concerned bodies
such as the headquarters of the Ministry of Land,
Infrastructure, Transport and Tourism in order totechnologically support such effective use andappropriate maintenance. But to be able to respond
more flexibly and appropriately, as shown in thefigure, beginning in FY2014, the Road Traffic

Road Traffic Department
Research Coordinator for Road Affairs
Research Coordinator for Road Traffic
Information Technology
Research Coordinator for Road DisasterPrevention
Traffic Engineering DivisionRoad Environment Division
Intelligent Transport Systems DivisionRoad Structures Department
Research Coordinator for Road
Structures
Bridge and Structures Division
Foundation, Tunnel and Substructures
Division
Pavement and Earthworks Division

Figure. New Organization of Road Related
Departments in FY2014
Department and the Road Structures Department
which include necessary research coordinators anddivisions have been set up to conduct surveys andresearch.
2. For effective use of the stock—Road TrafficDepartment
To reduce traffic accidents involving pedestrians orcyclists and relieve congestion, road space planningand improvement methods centered on pedestrians andcyclists and bottleneck countermeasures are being
taken. The accident rate on expressways is about 1/10of that on ordinary roads, and CO2 emissions of asmall-size car on an expressway are about 2/3 of thaton ordinary roads when the traveling speed on eachtype of road is assumed to be 80km/h and 20km/h
respectively. Improving safety measures and reducing
congestion on the existing ordinary roads, andconversion of trips from ordinary roads toexpressways
accordingtotheirpurposes,origin/destination and so on both help reduce traffic
accidents, congestion on ordinary roads, and CO2
emissions, and the Panel on Infrastructure

Development , Road Committee, Basic Policy
Sub-committee and National Arterial Road
Sub-committee have, as one theme, discussed theintelligent use of networks.
ITS Spots have also been placed along ordinaryroads, so road managers can now obtain more
information about road traffic. Furthermore, there isinformation about the movement of automobiles andpeople that private companies collect, process, andprovide. Various ways of using these types of
information are considered, andeffective
applications are expected to be constructed in order
to effectively use the existing stock including
networks.
In order to effectively use such existing stock, theRoad Traffic Department will mainly undertake thefollowing research.
(1) Improvement of safety for pedestrians and cyclists
 Methods of promoting safety countermeasures forroads in residential districts
 Methods of designing bicycle paths(2) Effective use of information and of information
communication technologies
Information and information communication
technology studies are undertaken assuming thatthese can be applied to improve many aspects of roadtraffic, and we wish to continue these initiatives in thefuture. Specifically, the following are given as
examples, Studies will include system design
considering necessity.
 Methods of clarifying the state of movement, suchas OD, of automobiles, bicycles, and pedestrians
 Methods of clarifying and evaluating the levels ofroad services
 Methods of clarifying hazardous spots
 Methods of clarifying congestion locations, causes,
and range of impacts
 Methods of smooth traffic and safe driving
assistance on expressways
 Methods of clarifying state of use of road networks
including their use after disasters(3) Road structures adapted flexibly to regional
conditions
3. For appropriate maintenance of thestock—Road Structures Department
In deteriorated road structures, problems haveappeared including breakage of steel, fallen concreteslabs, breakage of suspension bridge cables, crumblingof concrete lining of tunnels, and so on.
In response to the 2013 revision of the Road Act,
technology standards for maintenance wereenacted
in March 2014, and inspections, diagnosis, recording
and other maintenance will be conducted according tothese standards including that done by cities, towns,and villages. But to perform rational maintenanceunder harsh financial conditions, inspection methods
which are economical and rational, accurate methodsof assessing soundness, and asset management
methods are needed.
In order to maintain the functions of roads or to
rapidly restore them after a disaster, there must be nostructures on the road which have sustained fataldamage. For this purpose, it is necessary to develop
soundness evaluation methods with concepts common
to all types of road structures. This is not simply
soundness evaluation for maintenance purposes; it is aproblem that should be considered from the design
stage.
In order for road structure maintenance to be amethod rational and systematic from the structure
perspective and network functions perspective, theRoad Structure Department will conduct the following
researches.
(1) Appropriate inspections and evaluations
 Monitoring methods
 Inspection
methods
usingnon-destructive
inspection
 Soundness evaluation methods(2) Asset management
 Public risk evaluation method
 Comprehensive maintenance indices common tomost types of structures(3) Coordination design and maintenance concepts
among structures(4) Safety evaluation methods for non-structuralmembers which work united with structural members ,and new technologies and new materials etc.
We will clarify concepts of performance required
concepts of setting safety factors and concepts ofensuring safety (only safety factor/introducing failsafe) to study the adoption of new technologies andnew materials.
4. For Support for road administration—commonto both departments
Both the Road Traffic Department and Road
Structures Department will, in addition to the above,
work to spread research results
at academic
conferences, and coordinate with the MLIT
headquarters and other concerned organizations so theresults are reflected in technology standards andpolicies.
And of course, we will accept engineers from roadadministrations including those from cities, towns, andvillages, and aggressively provide them withtechnology consulting services.
[Sources]
Panel on Infrastructure Development , Road
Committee, 44th Basic Policy Sub-committee meeting,and 11th National Land and Arterial Road
Sub-committee, meeting documents (February 7,2014)
https://www.mlit.go.jp/policy/shingikai/s203_seisaku01.html
https://www.mlit.go.jp/policy/shingikai/s204_kokudokannsenn.html