22nd Infrastructure Technology Development Award 2020
Japan Institute of Country-ology and Engineering

As a result of examination, institutes and(JICE) was established as a public interest

researchers with the following technologies werecorporation to promote construction engineering inawarded the 22nd prizes.

Japan by conducting cutting-edge research anddevelopment activities.

The grand prize was awarded to “Liquefaction
Countermeasure for Existing Residential Areas”,

To provide more incentives for construction

while the two excellence prizes were awarded totechnology researchers and research institutes tothe “Educational System for Close Visualenhance the level of construction engineering

Inspection of Fatigue Failure in Steelmore effectively, JICE commenced Infrastructure

Bridges“ and the “Steel timbering erecting robot”.

Technology Development Award with Coastal
Development Institute of Technology (CDIT)

The two excellent prizes are introduced below.

under the auspices of the Ministry of Land,
Infrastructure, Transport and Tourism (MLIT).

For any inquiries/ comments please contact toJICE :Forty technologies competed for the 22nd

Homepage: http://www.jice.or.jp/

Infrastructure Technology Development Award.

(Japanese version only)

In principle, the applicants’ technologies must

E-Mail: webmaster@jice.or.jp

have been developed within the past five years,already applied to real sites.

Infrastructure Development Institute - Japan

Educational System for Close Visual Inspection of Fatigue Failure in Steel Bridges
Inspection training simulator system for effectively improving inspection skills
1. Background and opportunities fortechnological development
Fatigue failure is a type of deterioration on steel
bridges caused by aging. Early detection via
inspection is critical since the progression offatigue failure may cause members to break.
This makes improving inspection skills
essential. Classroom lectures based on currenttextbooks can be carried out relatively easily toeducate
inspectionengineers,butunderstanding the actual structure of a bridgein its entirety is difficult.
Furthermore, although the actual structure canbe observed while conducting practice fieldwork
on-site, a lot of effort is required to prepare andensure safety at the site, and the number ofstudents who can participate in fieldwork islimited. To supplement the advantages anddisadvantages of classroom lectures and on-sitepractice, we developed a simulator that makes
it possible to effectively learn about the areas
where fatigue
failures occur and their causes in a virtual space.
(Figure.1)

2. Details of the technology
The current simulator system uses the 3D gamedevelopment software Unity as a development
platform to create a 3D model of a bridge and toprovide a virtual reality (VR) environment. Thissystem allows the user to experience performing
an inspection on a virtual bridge using acomputer (Photo1) or head-mounted display(Photo 2), and has the advantage of not being
limited by time or place.
The bridges that can be examined and studied
within this system are simply-supported Igirder bridges with a reinforced concrete deckslab and box-girder bridges. (Figure.2)
The proposed system makes it possible toacquire basic knowledge of bridges andconstituent members for inspection, learn how
to assess and rank actual damage throughplenty of case examples of damage, become
proficient in identifying where dangerous crack
failures occur and their causes, and undergo
continuous training by identifying randomly
occurring damaged areas.
Photo-1 Computer version

Figure-1 Purpose of the system

Photo-2 Head-mounted display version
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Figure-2 Composition of IMS3

Beginners can acquire the basic knowledge offatigue
failureandinspection,
while
experienced inspectors can improve theirknowledge and skills in order to reliably
perform inspections.(Figure 3)
3. Range of application of the technology
This system can be used for inspection training
for all kinds of bridges.
4. Benefits of the technology

⚫

⚫

⚫

Using 3D technology makes it possible toobtain a three-dimensional bird's-eye viewof the bridge,thereby speeding up thelearning process compared to using atextbook alone.
Learning can be conducted at the user's
pace without being restricted by place ortime.
The technology makes it possible to provide
much greater efficiency, since practiceinspections of actual bridges can be carriedout indoors. Practical training can beacquired in a quarter of the time requiredfor on-site inspections.

5. Social significance and potential of thetechnology
With the revision of the Regulation forEnforcement of the Road Act (issued in March
31, 2014, and enforced in July 1, 2014), regularroad bridge inspections require a qualified
person with the knowledge and skills to carryout close visual inspections once every five years.
This led to a pressing social need for a more
effective way to educate inspection engineers.
The presently proposed system addresses theseissues by making it possible to effectively learn
through simulations of close visual inspection ina virtual space. Since this system can be easily
used on a desktop computer, we anticipate its
use at inspection workshops, study sessions andother training programs for bridge inspectionengineers of highway administrators and local
governments throughout Japan.

4(a) Interior of a virtual bridge(b) Explanation of the causes of damage(c) Damage ranking screen(d) Inspection result confirmation screen
Figure-3 Simulator screen

6. Adoption of the technology
FY 2019 Metropolitan Expressway Company
Limited: Interim Review of Inspection Engineer
Qualifications (Based on the Inspection
Procedure for Structures, December 2019)[Contact Information]
Technology Developer:
Metropolitan Expressway Company Limited／
Shutoko Technology Center／
Gotoh Educational Corporation, Tokyo City
University
TEL：+81-3-3539-9546
FAX：+81-3-3539-9546
E-mail：s.hina1942@shutoko.jp
TEL：+81-3-3578-5758
FAX：+81-3-3578-5762
E-mail：s.fujiwara@tecmex.or.jp

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Steel Timbering Erecting Robot
Technology for increasing the safety and productivity of mountain tunneling works
1. Background to and impetus for thedevelopment of the technology
Rockfall accidents on tunnel faces are
specific to mountain tunnels, and human
involvement in these accidents during steel
timbering erection works represent the mostcommon case of its consequences. As measures
to prevent such accidents, efforts to reduce them
have been made by taking measures to control
the loosening of ground, predicting rockfalls,and providing protection in a complex manner.
However, these measures tend to fall short incomparison to other extreme countermeasures.
JapaneseGuidelines
requireamachinery-based measure be implemented toprevent such accidents, as human involvementin such accidents will not occur if workers do notenter the tunnel face in the first place.

This led to the development of a “SteelTimbering Erecting Robot,” which is capable ofinstalling steel timbering for mountain tunnels
without requiring a worker to enter the tunnel
face.

Photo-1 Steel Timbering Erecting RobotFig. 1 Schematic drawing of the steel timbering erecting robot’s system configuration
62. Content of the technology
This technology is intended to enable
the operator to perform steel timbering erection
work alone in a mountain tunnel. This highaccuracy timbering erection, solely performed
through the operation of the robot from the cabseat, is achieved by combining a “timbering
position navigation system,” which consists ofdevices such as a surveying prism magneticallymounted on steel timbering, a “highperformance erector,” an auto-tracking total
station which is capable of holding steel
timbering and fine-adjusting the installation
position, and a “spraying arm,” capable ofspraying concrete while the steel timbering isheld. In addition, formerly required manpowered works are eliminated making it
unnecessary for workers to enter the tunnel face,through the spraying of concrete and tighteningof the crown joint using “steel timbering forautomatic erection,” which is equipped with aquick joint, holding the timbering to secure thelegs.

Holds the timbering
using the erector arm

After the positioning is completed,sprays concrete down to the bottom of the erector arm

Photo 4: Securing the legs of the steel timbering
3. Scope of application of the technology
Steel timbering erection works inmountain tunneling.
4. Effects of the technology⚫

Achieving the elimination of works
requiring human entry in tunnel faces forsteel timbering erection work⚫

Manpower saving in steel timbering
erection work⚫

Shortened work cycle⚫

Increased accuracy of steel timbering
erection

Photo-2 Positioning using the navigation system

Crown tightening

5. Social significance and potential of thetechnology
This technology can eliminate allworks involving human entry in tunnel faces forsteeltimberingerection,
significantly
increasing the safety against rockfall accidents
on tunnel faces during erection. In addition, it
saves manpower in steel timbering erection
work, increasing productivity through theshortening of the work cycle, and achieving
high-accuracy erection. This will contribute to
the improvement of the safety and productivity
techniques, which have long been a social
challenge in mountain tunneling. The
technology is expected to be adopted not only inconstruction sites in Japan and abroad, but also
in the field of mining.

Photo-3 Crown tightening, and positioning ofthe steel timbering
76.Track record of the adoption oftechnology
Adopted in Miyazaki No. 218 Hirasoko Tunnel
Building Work, March 2018 to March 2019
Applicant : Maeda Corporation
Technology Developer: Kazuhiko Mizutani
E-mail: mizutani.k@jcity.maeda.co.jp
TEL: +81-3-3265-5551

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About IDI and IDI-quarterly
Infrastructure Development Institute-Japan (IDI) is a general incorporated
association operating under the guidance of Ministry of Land, Infrastructure,
Transport and Tourism of Japanese Government.
IDI provides consulting services to facilitate international assistance to developing
countries, to promote international exchange of information and human resources,
and to support globalization of project implementation systems targeting bothdeveloped and developing countries in the field of infrastructure.
IDI has been publishing the free quarterly journal called “IDI Quarterly” since 1996
to introduce information regarding public works and construction technologies
developed in Japan, to foreign countries. We have distributed the journal toadministration officials in more than 90 countries around the world via e-mail.
It will be highly appreciated if you could send us your opinions, impressions, etc.
regarding the articles.
We also welcome your specific requests regarding technologies you would like tosee on following Quarterly issues.

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