Annual Report
2020
Port and Airport Research Institute Annual Report 2020

Message from the Director General

Message from the Director General

Creating Technologies
That Contributeto the World
港湾空港技術研究所長（うみそら研理事）

稲田雅裕

Masahiro Inada
Director General, Port and Airport Research Institute(Executive Director, National Institute of Maritime, Port and Aviation Technology)

In April 2016, three research centers – the National Maritime Research Institute (NMRI), the Port and Airport Research Institute (PARI), and the Electronic Navigation Research Institute (ENRI) – were merged to form a newnational research and development agency, the National Institute of Maritime,
Port and Aviation Technology (MPAT). Now a part of MPAT, all of us working at
PARI remain committed to maintaining our heritage as a research institute that has contributed to surveys, research, and technological advancementin port and airport development, and to continuing to serve our designated roles. After our predecessor organization, the Port and Harbour ResearchInstitute, was created as a division of the Ministry of Transport in 1962, the organization provided technical support on numerous port, harbor, andairport projects, including the development of Kashima Port and the construction of Haneda International Airport and Kansai International Airport, andalso conducted research activities that produced world-renowned results. Looking ahead, PARI will effectively collaborate with the two other research
institutes it has been integrated with, in addition to continuing to work closely with the National Institute for Land and Infrastructure Management(NILIM) at the Ministry of Land, Infrastructure, Transport and Tourism (MLIT), in order to develop and extend the collaboration and consolidation in
multidisciplinary research among the MPAT member institutes. By leveraging the synergistic effects of the consolidation of member institutes, PARI
will strive to achieve maximum results in its research and development.
This annual report summarizes PARI’s track record in FY 2019, the fourth year of the first mid-term plan (from FY 2016 through FY 2022). In this plan,
PARI is focusing on the following four research and development challenges: Coastal Disaster Mitigation and Restoration, Formation of Infrastructure
for Vigorous Economy and Society, Preservation of Marine Interests and Utilization of Oceans, and Creation and Utilization of Coastal Environment.
For Coastal Disaster Mitigation and Restoration, we have been conducting research on topics such as estimating the damage caused by maximum-level earthquakes, storm surges and high waves, analyzing tsunami-induced scouring, and studying structural stability.
For the Formation of Infrastructure for a Vigorous Economy and Society, we have been conducting research projects involving evaluation of thelong-term durability of infrastructures, development of inspection and diagnostic technology, improvement of existing facilities, development offacility upgrading technology, and examination of methods to improve cargo-handling efficiency at container terminals, etc.
For the Preservation of Marine Interests and Utilization of Oceans, we have been engaged in projects for the preservation of ports and harbors
on remote islands and other territories of Japan in general, development of acoustic video cameras that serve as basic technology enabling iConstruction, and development of reasonable design techniques to create offshore wind power plants, etc.
For the Creation and Utilization of Coastal Environments, our research has focused on developing a novel coastal ecosystem model that canquantify the amounts of blue carbon (i.e., mitigating effect) existing in various coastal areas, and also enable ocean-wave attenuation predictor
models (i.e., adaptation effect) while considering the effects on the ecosystem.
In executing these research activities, PARI will continuously strive to live up to its two major mottos, which are to conduct research at the world’s
highest level and to make sure that the results of its research are useful in actual projects. In addition, PARI will promote government-led strategicinternational activities, including contributing to the expansion of infrastructures overseas and providing technical assistance to other countries.
Furthermore, in order to tackle various technological challenges that encompass different research fields, PARI has internally set up five missiondriven centers (the International Research Center for Coastal Disasters, the Life Cycle Management Research Center, the Ocean Infrastructure andOffshore Wind Energy Research Center, the Productivity Improvement Research Center, and the Innovation Promotion Center), through which we
intend to continuously enhance our collaboration with private-sector companies as well as with the Regional Development Bureau and other divisions of MLIT that manage project sites where our technologies are implemented. In view of the increasing number of natural disasters such as
earthquakes, storm surges and high waves in recent years, there is an urgent need to improve the resilience of our national land. While recognizing
the unique position of PARI as a research institute responsible for conducting practical R&D activities that can be utilized in actual on-site operations
under the demanding natural conditions specific to Japan, we intend to continuously leverage all knowledge, human resources, and other assetsthat are available at PARI in order to provide disaster-prevention education to the public, respond to emergencies during earthquakes, tsunami, andother disasters, and assist post-disaster recovery efforts in a reliable manner.
We would greatly appreciate your continued support.

CONTENTS
12345

Outline of Organization

02p

Management Strategy

03p

Structure of Research Themes in FY 201904p

Research Themes and Activities in FY 201905p

Fundamental and Exploratory Research

14p

01 PARI Annual Report 2020

6
7
8
9

Published Research Papers

19p

Public Relations

20p

Outstanding Research Activities

21p

PARI Events

22p

Outline of Organization
Administrative Staff and Researchers, and Budget

1

Administrative staff
20

Researchers(Others)
38

Commissioned research income, etc.
1,523 million yen

Researchers(with PhD)
45
As of April 1, 2020 (In Yokosuka)

Operational subsidies
1,231 million yen* The graph above shows the budget for technical fields related to ports,
waterways, coasts, and airports.

Organizational Structure
President

Distinguished
Researchers

Strategic Planning andManagement Office

Auditors

National Institute of Maritime,
Port and Aviation Technology (MPAT)

Vice Presidents(In Yokosuka)

Administration Department

Planning Department

Administrative Coordination andDisaster Prevention Department

Director for Research Planning
Director for Promotion of Intellectual Property Utilization
Administrative Division(In Yokosuka)
National Maritime
Research Institute(NMRI)

Port and Airport
Research Institute(PARI)

Electronic Navigation
Research Institute(ENRI)

Planning, Coordination and Disaster Prevention Division
Facilities Division
Wave Group

Coastal and Ocean Engineering Department

Maritime Structures Group
Coastal and Ocean Development Group
Marine Information Group

Marine Information and Tsunami Department

Marine Environmental Information Group
Tsunami and Storm Surge Group

Coastal and Estuarine Environment Department

Coastal and Estuarine Environment Group
Coastal and Estuarine Sediment Dynamics Group
Soil Mechanics and Geo-Environment Group

Geotechnical Engineering Department

Foundations Group

Fellow
Managing Director for
Research Affairs

Earthquake Disaster Prevention Engineering Department

Senior Director forInternational Affairs
Senior Director for Research

Soil Dynamics Group
Soil Stabilization GroupEngineering Seismology Group
Earthquake and Structural Dynamics Group
Structural Mechanics Group

Structural Engineering Department

Materials Group
Pavement Group

Frontier Technology and Engineering Department

Sensing and System Technology Group
Robotics GroupOil Spill Response GroupInternational Research Center for Coastal Disasters
Life Cycle Management Research Center
Ocean Infrastructure and Offshore Wind Energy Reorganized on October 1, 2017
Research Center
Productivity Improvement Research Center
Innovation Promotion Center

Established on April 1, 2017
Established on February 1, 2020

As of April 1, 2020PARI Annual Report 2020 02

Outline of Organization

FY 2020
Annual Budget
2,754 million yen

Total
103

Management Strategy

2Management Strategy

Mid- and Long-Term Objectives(FY 2016 to FY 2022)

Mid- and Long-Term Plans(FY 2016 to FY 2022)

The Minister of Land, Infrastructure, Transport and Tourism(MLIT) sets mid- and long-term business goals for the National Research and Development Agency, National Instituteof Maritime, Port and Aviation Technology to achieve. These
goals stipulate our operations as follows.

The MLIT sets mid- and long-term goals. In response tosuch goals, MPAT sets mid- and long-term plans to achieve
the goals. Among such plans, important points in maximizing
research and development results and improving the qualityof other projects are outlined below.

Basic Policies for Structural Reform of Independent Administrative Institutions were decided in a Cabinet decisionon December 24, 2013 (hereafter called “Basic Policies for
Reform”). Based on these policies, the National Maritime
Research Institute (NMRI), Port and Airport Research Institute (PARI), and Electronic Navigation Research Institute(ENRI), which were National Research and Development
Agencies operated under the jurisdiction of the MLIT, were
integrated into the National Institute of Maritime, Port andAviation Technology (hereafter called “MPAT”) to implement the policies.
Article 2, paragraph 1 of the Act on General Rules stipulates as follows: some clerical tasks and business require
sound implementation from the viewpoint of general welfare including stabilization of people’s life and socioeconomy, but at the same time do not require government-led
implementation. Some of these clerical tasks and businesses face the risk of neglect when their operation is
entrusted to private entities, so MPAT was established toeffectively and efficiently conduct their operation.
In consideration of the previous roles of each institute,
MPAT is required to continue to make full use of its accumulated wealth of knowledge and stature, and to proceedwith research and development according to the Basic
Policies for Reform. In addition, MPAT will constantly review research contents and select research areas to address changes in the social environment. At the same time,
MPAT will more actively engage in research and development activities to solve policy challenges in each field,
such as conducting research in emerging fields.
MPAT has promoted research and development in eachfield, cultivated technological seeds, and accumulated
specialized knowledge. Thanks to MPAT’s legacy, such
multidisciplinary research became viable. In considerationof this background, MPAT will efficiently and effectively
implement multidisciplinary research including “Promoting
the protection of maritime interests and the utilization andapplication of marine-resource/marine-renewable-energy
development and other projects”. Through such implementation, MPAT will help put national policies into practice.
Furthermore, MPAT considers that it is important toreturn the benefits achieved through research and development to society, as well as to cooperate with external
institutes and to widely disseminate research results. In
addition, MPAT is committed to strategically implementing international activities as follows: active participationin projects to formulate international criteria and standards; international promotion of Japanese technologies
and systems through international cooperation; and otheractivities.
As outlined above, MPAT’s missions are based on the
MLIT’s Basic Plan for putting MLIT-recommended policies into practice. Today, Japan faces various important
challenges. By realizing these policies, we can solve suchchallenges.

1. Promotion of multidisciplinary research and other activities
MPAT will efficiently and effectively implement multidisciplinary research spanning research fields of the three pre-integration institutions to contribute to putting the following policies into practice: promotion of ocean utilization, enforcementof international industrial competitiveness, and other policies.

03 PARI Annual Report 2020

2. Research and development of technologies associated withports, water ways, coasts, and airports and other activities
MPAT will focus on the research and development challenges detailed in the following pages, to devise the following
MLIT-recommended initiatives: disaster-prevention and disaster-reduction countermeasures for port and airport facilities;
countermeasures for facility obsolescence of existing structures; and initiatives to create maritime-development hubs.
Among basic research, MPAT also actively engages in research to understand the mechanisms of ocean waves andbeach transformation and principles and phenomena regarding the dynamic behavior of the ground and structures.
MPAT also uses its foresight and flexibility to accurately
address emerging research which might lead to new research results.
3. Returning benefits from research and development results
to society
MPAT will try to resolve technological policy challenges, toaddress disasters and accidents, to enforce bridging functions, to promote and utilize intellectual property right, andto enhance the transmission of information and publication.
4. Promotion of strategic international activities
MPAT will contribute to international standardization andcooperate with overseas institutions.

MPAT Operation Management
MPAT will focus on rapid decision-making to engage instrategic institutional operations.
MPAT will also hold the following meetings for multi-faceted investigation of various operational agendas from a broad
perspective:
1. Management strategy meetings: In-house meetings formaking decisions on important issues related to the core
principles of MPAT management
2. Board of Directors meetings: Weekly meetings involving all
executives and division managers as well as the three directors of the Administrative, Coordination and Disaster Prevention Department
3. Board of Councilors meetings: Meetings to gather insightsfrom independent experts who have broad and deep knowledge
4. External Evaluation Board: An external body in which third
parties objectively and technically evaluate MPAT’s research

Structure of Research Themes in FY 2019
Research
Field

Research Theme

Research Subtheme① Research on strong ground motions
and damage predictions in the case of thegreatest earthquakes

Fundamental Research

Strong motion earthquake observation in port and airport area (2A②)

Fundamental Research

Investigation of earthquake disaster (2A②)

Fundamental Research

Development of estimation method for near-fault strong ground motions

Fundamental Research② Research on damage-reduction
techniques against the greatest
earthquakes

Applied Research
Applied Research③ Research on the interaction ofearthquakes, tsunamis, and high waves
with ground dynamics

Fundamental Research① Research on ICT-based decision

Development Research

Applied Research

Development of countermeasures for early exhibition of seismic performance of coastal facilities
Study from geotechnical view-point on stability evaluation method of coastal structure subjected
to high waves (1C②)
Stability evaluation of offshore structures against washout, cavity formation, etc. and development☆
of countermeasure techniques (1C②)
Development of a 3-dimensional simulation model for drift behavior and its application to a
2-dimensional simulation model

Development Research

Development of multi-observation based tsunami forecasting method

Fundamental Research

Development of the estimation method for local scour around coastal structures due to tsunami

Development Research

Application of the particle method to the large deformation of port structures due to tsunami

Fundamental Research

Elucidation of oceanographic phenomena based on central processing and analysis of observation
data

Applied Research① Research on storm surge, wave and
1C Research on Mitigation maximum damage estimation
and Restoration of Storm
Surge and Wave Disasters

A study of seasonal and regional statistics on swell observed in Japanese coast
Development of a harbor tranquility analysis method for local wind waves and ship waves in a
harborEstimation of wave transformation around damaged structures to evaluate remaining performancefor sheltering

Development Research
Applied Research
Applied Research

2. Formation of Infrastructure for Vigorous Economy and Society② Research on the technology to reduce
maximum storm surge and wave disasters① Research and development forenhancing the operations of ports,
2A Research on
Enhancement of Port and harbors, and airports
Airport Performance for② Development of technology to assist
Industrial Competitiveness efficient and effective development ofports, harbors, and airports① Research on technologies forprolonging the life of infrastructure
2B Research on Life
Cycle Management ofInfrastructures

Assessment of possible maximum storm surge hazard by using storm-surge-wave coupled model☆

(All research items marked “2A②” in this Table)
Fundamental Research

Evaluation of longterm durability of concrete, steel and various materials based on exposure test

Fundamental Research

Evaluation of applicability of sustainable materials in the marine environment

Fundamental Research

Development of the performance evaluation method in protective coating for marine structures

Fundamental Research

Evaluation of the durability of various materials under severe environments

Applied Research③ Research on maintenance andmanagement systems for infrastructure① Research on techniques to improve or
renew existing facilities② Research on effective use andtechniques of treating construction
byproducts

Study of the effects of steel mesh in concrete pavement used at airports from the design andimplementation perspectives (2A②)☆ Systematization of repair and strengthening of marine concrete structures

Study on application of inspection and diagnosis systems for improvement of performance
evaluation of marine structures

Applied Research
Development Research

Development of adaptive technique for inspection vehicle to disturbance in operation (2A①)

Applied Research

Study on maintenance planning of port facilities in term of LCC optimization

Applied Research

Development of quality evaluation method for ground improvement using geophysical exploration(2A②)

Fundamental Research
Fundamental Research

Study on process leading to rupture of pier structure for high definition of performance regulation☆

Applied Research

3. Preservation of Marine
Interests and Utilization of
Oceans3A Research on
Development andUtilization of Oceans② Research on infrastructure technology
for utilization and development of oceans

Development Research

4. Creation and Utilization of Coastal
Environment

4A Research on
Enhancement andUtilization of Coastal
Ecology

Fundamental Research

Development of next-generation acoustic imaging system (2A①)

Development Research

Research on adaptation of the machine guidance for an underwater excavator (2A①)

Applied Research

4B Research on Coastal
and Estuarine Processes① Research on coastal protection andmaintenance of waterways and mooringbasinsStudy on floating breakwater equipped with wave power generation device

Applied Research

Fundamental Research
Applied Research

Research on the estimation method of wave force acting on offshore wind power facilities
Elucidation of the horizontal resistance characteristics of pile foundations for offshore wind power
plants under various fluctuating loads (2C①)
Validation of the newly developed global dynamic model for the projection of atmospheric CO2☆
uptake rate and inundation control in shallow coastal ecosystems☆

Coastal geotechnical/geomorphological design for disaster mitigation and ecological environment☆ Cross-sectional observation and analysis of atmospheric and oceanographic issues at bay mouths

Fundamental Research

Analytical study of macro-organisms dynamics on a coastal ecosystem simulation

Fundamental Research

Development of the methods for increasing ecosystem functions in eelgrass meadow

Applied Research③ Research on countermeasuretechnologies against sea oil spill

Technological development on advanced ship mooring system in port

☆ Development of analytical methods for the topographic dynamics of carbonate islands

Development Research

Fundamental Research② Research on the water-environment
simulation and analysis in inner-bay

Study on technique of wave sheltering for isolated coral reef area

Development Research

Fundamental Research① Research on coastal-ecosystemutilization

Enhancement of accuracy of method for evaluating mechanical properties of composite
geomaterials based on microstructural feature
Development of technique increasing capacity of disposal site for dredged soil

③ Research on management andutilization of waste disposal sites at sea① Research on port construction andmanagement in remote islands

Study on wave forces on the structural members of protective facilities under storm surges, highwaves, and tsunami (1B②)
Proposal of evaluation method to estimate the productivity of the container terminal system
introduced AI and ICT technology or other method

Applied Research

Applied Research② Research on systems for inspecting
and diagnosing infrastructure

2C Research on
Effective Use of Existing
Infrastructure Facilities

Applied Research

Numerical analysis of coastal current by numerical simulation and data assimilation

Development Research

Development of oil spill response technology for next generation

Fundamental Research

Developing future projection model of coastal change in the context of climate change

Fundamental Research

Observation of coastal phenomena at HORS and development of numerical simulation of
topography change for port and surrounding beaches

Fundamental Research

Study on sediment transport in estuary and deposition process in navigation channel

Fundamental Research

Study on applicability of airborne laser bathymetry for topographic monitoring in coastal zone ofsea shore* Special research involves high-priority research topics on which PARI must conduct studies intensively. PARI allocates significant human resources and funding to these projects, and also arranges crossfunctional research systems extending beyond the basic organizational structure within PARI as needed, in order to accelerate research.

PARI Annual Report 2020 04

Structure of Research Themes in FY 2019

1B Research on Mitigation support systems
and Restoration of Tsunami
Disasters② Research on the development oftsunami-resistant ports

Study on the evaluation and analysis of liquefied ground behavior and effective countermeasures
under sequenced earthquake motions
Development of seismic performance evaluation method for offshore wind turbines and coastal☆
structures against the largest earthquake motions

3

1. Coastal Disaster Mitigation and Restoration

1A Research on Mitigationof and Restoration from
Earthquake Disasters

Item on the Research Agenda(☆indicates special research*)

Type of ResearchResearch Themes and Activities in FY 20191A

Research on Mitigation of and Restoration from Earthquake Disasters

Background and Objectives

4
Research Themes and Activities in FY 2019

• In the event of large-scale disasters including Nankai megathrustearthquakes and earthquakes in the greater Tokyo area, it is required
to secure necessary trunk line cargo transportation soon after anearthquake and to quickly secure the requisite minimum transportation of key emergency supplies for recovery and reconstruction. In
addition, the interaction of earthquakes, tsunamis, and high waves
with the ground might cause coastal disasters, so it is necessary to
reduce such risks.
• Therefore, the themes of this research cover research and development which simultaneously achieves the two goals of improving
earthquake resistance and reducing construction costs. These twogoals can be achieved through diagnosis and performance verification of earthquake-resistance of facilities which address the properties of long-period and long-duration earthquake ground motion,
which is expected to occur during a subduction-zone megathrustearthquake, as well as the properties of earthquake ground motion
caused by local ground characteristics. Research and development
are being conducted mainly on methods for investigating and diagnosing earthquake resistance as well as construction methods that
improve the resistance of existing facilities with limited design lifethat were erected during the era of rapid economic growth without
disturbing their use.

Research Topics

Research and development comprises the following three subthemes:i) Research on strong ground motions and damage predictions in
the case of the greatest earthquakes
Subduction-zone megathrust earthquakes may cause the greatest
and long-duration earthquake motions, so we will develop techniques
for predicting such motions. Also, we will develop techniques for predicting liquefaction and structural damage caused by such motions.
ii) Research on damage-reduction techniques against the greatest
earthquakes
We will suggest the most effective countermeasures under given
limitations to effectively promote seismic strengthening of existing
structures. In doing so, we will actively utilize damage reduction andstrengthening techniques that use novel materials, structures, and construction methods. Especially, as measures for improving earthquake
resistance of industrial complexes, we will consider maintaining thefunctions while reducing costs for overall plants, and then develop investigation, diagnosis and countermeasure techniques which minimize
usage limitations of plants. In addition, we will develop methods to rapidly evaluate damage levels on site immediately after a disaster as wellas emergency restoration techniques.
iii) Research on the interaction of earthquakes, tsunamis, and highwaves with ground dynamics
We will proceed with research on the following interaction problemsof earthquakes and ocean waves with the ground: stability evaluation
against seabed liquefaction, washout, cavity formation and collapse under earthquakes or under ocean waves; a mechanism in which a breakwater foundation loses its bearing capacity in the presence of tsunami;
and other interaction problems. Also, we will use numerical simulation
models, model experiments (on a centrifuge and a large-scale fluidtank), and other methods to investigate earthquake-induced submarine
landslides, the resulting tsunamis, ground dynamics including deformation and failure under the influence of tsunami and high waves, as wellas their countermeasures.

Activities in FY 2019

• We obtained 1,900 strong motion earthquake records during the period between January to December 2019. Of those data, the motion
recorded at the Port of Soma showed the maximum amplitude witha maximum acceleration of 159 Gal, which was caused by the earthquake (M6.4) that occurred off the coast of Fukushima Prefecture on
August 4. As progressive efforts had been made to implement a system that would automatically distribute by email preliminary seismic
motion data as they were acquired, preliminary data on the earthquake were transmitted roughly 10 minutes after it occurred. In addition, we collaborated with the MLIT and the Regional Development
Bureaus to improve the system, etc. concurrently with the upgradingof strong-motion seismometers.
• Concerning the RTK-GNSS-based system called “Berth Surveyor”
that was developed in the previous year to swiftly determine thesafety of mooring facilities following major earthquakes, we improved
its display function and also held discussions with the MLIT and theRegional Development Bureaus on ways for using the system. Information on the system was disseminated to related parties, and its
trial implementation was done on site.
• We conducted fundamental researches on the issue of the discretization of fault planes, etc., with a view to developing a comprehensive
strong-motion prediction method that can not only take into consideration the strong ground motions due to the rupture of asperities inthe deeper parts of the fault but can also take into account the effectsof shallower slip which was widely recognized after the occurrence ofthe Kumamoto earthquake.
• We evaluated and analyzed the liquefaction behavior of grounds subject to successive earthquake motions or had fine content, and suggested a technique for suppressing the amount of internal ground flow
and boiling that would occur with the propagation of liquefied zones.
• Concerning offshore wind turbines, we started developing an analytical code for elucidating their behavior when subjected to various
external forces including seismic motions, wind, etc. and developinga reliable method for evaluating their seismic performance.
• In order to develop a structure that can achieve desired seismic performance at an early stage after a major earthquake, we examined a
new method for retrofitting existing pile-supported mooring facilities
by installing struts and new piles. In addition, we conducted shake
table tests using scale models and analyzed the test results to elucidate the basic characteristics of their behavior during earthquakes
and how their seismic performance could be improved.
• We conducted stability evaluations and analyses of washout and cavity formation caused by various dynamic external forces resulting fromearthquakes, waves, and currents, elucidated their characteristics
and mechanisms, and evaluated novel countermeasure technologies
that could effectively suppress such washout and cavity formation.
• We developed a centrifuge model-based experimental method forstudying the rupturing behavior of grounds caused by waves and currents, and examined a method for evaluating the stability of coastal
structures against high waves from a geotechnological perspective.

Newly installed pile

Existing pile

Strut

A new method for improving the seismic performance of an existing pile-supported mooring facility by installing struts and new piles

05 PARI Annual Report 2020

Research
Research
Themes
Themesand and
Activities
Activities
in FY
in2019FY 2019

1B

Research on Mitigation and Restoration of Tsunami Disasters

Background and Objectives

Research and development comprise the following two sub-themes:i) Research on ICT-based decision support systems
We have previously developed a system for rapid forecasting of tsunami inundation, which utilizes offshore-tsunami waveforms observedby GPS-mounted wave buoys. For highly reliable tsunami prediction,
we will additionally utilize ground deformation data obtained by on-land
GPS base stations and remote-sensing information including ocean HF
radars, and will refine the system. To ensure the safety of evacuationsites, it is necessary to assess not only tsunami-induced inundation
depth but also the tsunami velocity and floating objects to determine
the resistance of structures and even to assess fires, which are associated with floating objects. So, we establish an integrated simulation
system which can assess these risks.
ii) Research on the development of tsunami-resistant ports
We will clarify the structures of violent flows, scours around structures induced by large tsunami-overflows, and the influence of drifting
objects including ships and vessels on the damages. Then, we will develop a method of designing tsunami-resistant breakwaters and otherfacilities as well as a method of planning tsunami-resistant ports. We
will also develop a 3-D multiphysics numeric calculation model thatincorporates novel calculation methods such as particle methods andthat can perform computations while considering both fluids and solids
as one, to be used as a new design and planning tool, in addition to thenumeric calculation models that were previously developed. Moreover,
we will conduct a large-scale model experiment to validate the robustness and accuracy of the numerical model, and will understand complex tsunami phenomena in port cities.

Ground truth

Conventional method

New method

Score: 0.52

Score: 0.66

Comparison of accuracy in rectangular fault tsunami source estimation between the conventional and new methods• Regarding the development of a method for estimating local scourthat a tsunami causes around structures, we conducted large-scale
hydraulic experiments and performed numerical calculations on local scour that occurs near the breakwater head, and identified thecharacteristics of the large eddy that occurs around the head. In addition, we conducted experiments on the scour that occurs behindthe breakwater due to tsunami overflow and clarified that the rubble
mound suppresses overflow-induced scour.
• Concerning the application of particle methods to tsunami-induced
large deformation of port structures, we developed the multi-physics
model based on the Discrete Element Method and a porous model tosimulate the behavior of various rigid objects, e.g. mounds, blocks,
caissons. In addition, we have developed a novel wave-generation
model that considers the incident wave height as the only parameterand built a framework in which the model can be easily connected to
2-D planar simulation models.

(2-D simulation)

Activities in FY 2019

• As for the development of a 3-D simulation model for drift behavior
and its application to a 2-D simulation model, we conducted the experiments on drift objects in a coastal area including a port and studied the methods of coupling the fluid model and drift object modelthat are integrated in the 3-D simulation model. In these experiments,
we acquired 3-D data using acceleration sensors embedded in drift
objects of various shapes and analyzed plane behavior of the drift
objects by image analysis.
(3-D simulation)
Analysis of flow around breakwater in a numerical wave tank utilizing the particle method

PARI Annual Report 2020 06

Research Themes and Activities in FY 2019

Research Topics• Aiming to build a multi-observation based tsunami forecasting
method, we developed a new tsunami source inversion method thatutilizes data-driven bases created by time-reversal imaging, which
improved the accuracy of the tsunami source estimation by 14%. In
addition, we succeeded in developing a reciprocal-theorem-based
technique that reduced the cost of calculating Green’s functions,which is necessary for the tsunami source estimation, to approximately 1/100. These new technological inventions allow us to perform the tsunami source analyses with ultrahigh resolution, which are
expected to improve the accuracy of tsunami waveform prediction.

4• Since the Great East Japan Earthquake in 2011, we have studied
stable structures against tsunami overflows and developed a numerical simulation model to predict the drifting of debris generated by
the destruction of buildings. However, complex behaviors of tsunami
run-up on land and the resulting damages are not fully understoodand modeled yet. In addition, regarding a technique for real-time inundation forecast, which is expected to be utilized for evacuation andother purposes, only data from GPS-mounted wave buoys is used;other valuable data is not fully utilized yet.
• Therefore, we are aimed for changing disaster prevention and reduction countermeasures into a pre-disaster stage from post-disasterone, and will conduct research to establish resilient coastal zones
which can withstand the most severe tsunamis, i.e., to protect lives
against the most severe tsunami, to avoid catastrophic socioeconomic damages, and to enable early recovery and reconstruction.

Research Themes and Activities in FY 20191C

Research on Mitigation and Restoration of Storm Surge and Wave Disasters

Background and Objectives

4
Research Themes and Activities in FY 2019

• Since Typhoon Vera struck in September 1959, there have been nodevastating storm surge and wave disasters in Japan. However, theU.S. suffered severe damages due to Hurricane Katrina in September
2005, and so did the Philippines due to Typhoon Haiyan in November
2013. In future, global warming might bring higher storm surges andwaves than those we have expected in Japan.
• Therefore, this research is aimed for changing disaster prevention
and mitigation measures into a pre-disaster stage from post-disaster one and focuses on how to mitigate damage by the maximum
storm surge and wave conditions and how to rapidly recover andreconstruct after the damage has occurred. Therefore, we conduct
research to encourage hard and soft measures. Specifically, we willdevelop a numerical model to estimate the maximum storm surge
and wave and their damage and will also develop design methods tobuild robust structures.

• Regarding the development of a harbor tranquility analysis method
for local wind waves and ship waves, we suggested a novel harbor
tranquility analysis method that considers ship waves, and quantitatively compared the cargo-handling efficiency between the conventional and presented methods. In addition, we conducted anexperiment using a wind-wave flume to study the process of wave
development under strong wind in a port, and discovered that thevariation of water-surface friction velocity with wind velocity might
depend on the initial state of the water surface.

Research Topics

Research and development comprises the following two subthemes:i) Research on storm surge, wave and maximum damage estimation
We will develop the following to determine the characteristics of thedamage due to the maximum storm surge and wave: an accurate storm
surge prediction model, which incorporates a weather model; and a new
method based on a 3-D fluid model to simulate tidal levels and flows at
the time of storm surge. Also, we will employ a high statistical analysis
to estimate the effects of global warming on the maximum storm surge
and wave and long-term variations in these statistics. In addition, we
will establish a calculation technique to estimate the following wave
transformations: the wave sheltering effects of breakwaters damaged
through sliding, depression and others; and overtopping prevention effects of seawall having collapsed parapet, dispersed wave-dissipating
blocks and other damages.

Calculation of generation and propagation of ship wave from a sailing freight vessel (5,000 WT) in a port

• For the evaluation of wave transformation and propagation characteristics around damaged structures to consider remaining performancefor sheltering, we studied planar harbor waves behind submerged
breakwater to verify the accuracy of the NOWT-PARI Boussinesq
model. In addition, we performed calculation of wave transformation on model ports to study the wave-controlling performance of the
breakwater partially submerged by disasters and newly constructedsubmerged breakwaters, and quantitatively elucidated the effects ofthe breakwaters on harbor tranquility.

ii) Research on the technology to reduce maximum storm surge
and wave disasters
We will elucidate structural stability under complex conditions inwhich unexpectedly high water level due to storm surge coincides withhigh waves. In addition, we will investigate methods of estimating thedamage on structures due to storm surge and waves and countermeasure against such damages, and develop a method to design robust
structures.

Activities in FY 2019

• Regarding the central processing and analysis of observational dataon oceanographic phenomena, we organized the wave data observed through the Nationwide Ocean Wave Information Network forPorts and Harbours (NOWPHAS) in 2018 and compiled the annual
wave observation report. Concerning the high waves caused by Typhoon Faxai that passed through Tokyo Bay from south to north, we
analyzed the wave data acquired at the NOWPHAS station “Dainikaiho” and estimated them with a wave model.
• For studying the seasonal and regional characteristics of swells observed along the coast of Japan and the mechanism of the swelldevelopment, we organized data to better understand the wave directional spectrum with multi peaks and the occurrence characteristics of wind waves and swells. It led that wind waves appear more
frequent on the coast facing the Sea of Japan where wind waves
caused by the winter monsoon are prominent. Meanwhile, swells playa larger role on the coast of the Pacific Ocean where swells generated by summer typhoons reach the shore. We also quantitatively
confirmed that wave directional spectrum with multi peaks appeared
more frequently on the Pacific coast than on the Sea of Japan coast.

07 PARI Annual Report 2020

Shortening of swell wave period caused by partially submerged
breakwater (compared to 12s)

• To assess the possible maximum storm surge hazard using a storm
surge and wave coupled model, we first examined the reproducibility of storm surges along major coastal areas of Japan using the
ROMS ocean model, and then focused on a sample port to estimate
the storm surges and the associated coastal inundation using the
ROMS-SWAN coupled model considering wave setup. In addition,
we applied Emanuel’s MPI theory to calculate the maximum intensity
to which typhoons could develop and evaluated a method for defining the worst class typhoon.
• Regarding the study on wave forces acting on the structural members of protective facilities under storm surges, high waves, and tsunamis, we conducted a hydraulic experiment to elucidate the wave
force acting on seawalls having complicated structural cross sections which were damaged by Typhoon Faxai. In addition, we evaluated methods for estimating the maximum and time-series wave
forces by applying ANN to the experimental data. We also verified theefficacy of a work method to prevent the detachment of geotextile
sheets installed on backfill stones of seawalls by waves in a largescale experiment.

Research
Research
Themes
Themesand and
Activities
Activities
in FY
in2019FY 2019

2A

Research on Enhancement of Port and Airport Performance forIndustrial CompetitivenessBackground and Objectives

Activities in FY 2019(Sec)

Research Topics

R&D on technology that contributes to improving the capability andfunctions of ports and airports
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The graph indicates the idle time of different cargo-handling machines waiting for each other. It is apparent that RTG cranes andtrucks (TRK) are waiting for each other. (Data is of a certain weekwhere the required cargo capacity is 1,500,000 TEUs per year, assuming use of CONPAS, on-dock depots, and remote-control RTGs.)(Sec)

Average
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iii) Proposal of new technology for container terminal operations
We will conduct R&D on operation support technology (damage inspection system) pertaining to the container damage inspection system, autonomous control of gantry cranes, remote control of RTG,
adoption of AI, etc., which have been funded with PRISM, etc., and will
also provide technical support to the government.

7:00
4:00

ii) Proposal of planning method for automated container terminalby quantitative numerical simulation
We will formulate and suggest quantitative-simulation-based planning technology applicable to container terminals using the quantitative
simulations previously run on Tokyo Port, Yokohama Port, Nagoya Port,
Osaka Port, Kobe Port, and Hakata Port, while referencing the automated terminal planning guidelines currently being drafted by PIANC
for issuance in 2021.

1:00i) Proposal of evaluation method to estimate the productivity of
the container terminal system introduced AI and ICT technology
or other method
We will create data models for assessing various facility arrangements at the 1,000-m extension container terminal on New Honmoku
Pier at the Port of Yokohama and evaluating the effects of CONPAS,
remote-control RTG, and on-dock depots, and suggest suitable functions to be implemented, how to utilize those functions, and arrange
facilities based on quantitative evaluation using AutoMod simulations.

Day 3

One operator is assigned to four remote-control RTGs. Therefore, if
more than one RTG must be operated simultaneously, idle time will
occur while waiting for the operator to complete the operation of
one crane at a time. The graph indicates such idle time.

As shown above, the on-premises cargo-handling capacity is clearly
more critical than the throughput at the gates when large quantities ofcontainers must be handled. Based on this finding, it is considered thatuse of an AI-powered terminal system that enables programming of efficient operations for the storage space and cargo-handling machines
could improve the aforementioned issues.

PARI Annual Report 2020 08

Research Themes and Activities in FY 2019i) Proposal of evaluation method to estimate the productivity of
the container terminal system introduced AI and ICT technology
or other method
As for our specific activities that were conducted during FY 2019,
we focused on New Honmoku Pier at the Port of Yokohama and ran
AutoMod simulations on the gates, storage space, and overall pier operation while specifying numbers of GCs, RTGs, and gate lanes basedon data from Minami Honmoku Pier MC-1 through 4 of Yokohama Portand assuming cargo-handling throughputs of 1,000,000 TEUs per year
and 1,500,000 TEUs per year, which are more than the planned cargohandling capacity. During this process, we created and evaluated data
models related to the CONPAS reservation system, the prior clerk system, remote-control RTGs, and on-dock depots.
At a throughput of 1,500,000 TEUs per year, there would be many
trucks waiting for their turns on the premises, so we determined that it
would be insufficient to have the number of RTGs in proportion to how
they are deployed at MC-3 and MC-4. Meanwhile, we also found thata long line of trucks waiting for their turns would still form even at a
throughput of 1,000,000 TEUs per year. However, as there was waitingtime for both RTG cranes and trucks, such congestion could be improved by devising a method that enables more suitable programming
to optimize the matching between different cargo-handling machines.
By simply adopting on-dock depots that can actively perform cargohandling at night, these shortcomings could be improved significantly.
As for the efficacy of CONPAS, we were able to verify it based on thefact that the amount of cargo passing through the gates had increased.
As for the remote-control RTGs, we found that having one person
simultaneously handle operations of four RTG cranes during busy times
would create idle time for the RTG cranes.

4• As Japan’s population keeps declining, with the elderly comprising an ever-growing part of its society, and as many infrastructures
built in the past continue to deteriorate, technological solutions areneeded in order to achieve the following goals: Improve the global
competitiveness of the industries in Japan, which are the main sourceof the country’s vitality; identify means of maintaining the functions of
the country’s ports, harbors, and airports that are essential for sustaining people’s living; and maintain, upgrade, and repair the aging
infrastructures with limited financial and human resources efficiently
and effectively while also trying to extend their lifespans.
• Toward the aforementioned goals, PARI has been committed to R&D,
etc. for enhancing the functions of ports, harbors, and airports. As forthe related subthemes that contribute to raising the country’s competitive edge on a global scale such as adoption of policies on internationally strategic ports and enhancement of metropolitan airport
functions (improvement of Haneda Airport), etc., we have been conducting R&D activities in a comprehensive manner throughout PARI.
• Concerning this particular research theme, we have been developing certain technology that will expand Japan’s global competitive
advantage, including implementation of ICT, AI, and other information technology at container terminals, and automation of cargohandling services.
As for PARI’s activities to create technology that enables efficientand effective development of port and airport facilities, reports areprovided under other research themes. Such activities include formulation of work and inspection methods that are better tailoredto port and airport facility operations and work coordination, construction of large-scale facilities for rapid functional improvement,
improvement of the seismic performance of facilities, maintenanceand management of facilities after they are built, and improvementof existing facilities.

Research Themes and Activities in FY 20192B

Research on Life Cycle Management of Infrastructures

Background and Objectives

4• The ports, airports and coastal infrastructures that have been inservice for a long time are increasing, but financial resources andthe number of engineers for facility maintenance are limited. As important port, airport, and coastal infrastructure functions should bemaintained, the strategic maintenance, renewal, and other measures
to maintain such functions are strongly required.
• Therefore, we are trying to establish methods for structure design
and material selection which are excellent in terms of maintenance,
and will develop techniques and technologies regarding various
countermeasures for maintenance phase.

Research Topics

Research Themes and Activities in FY 2019

Research and development comprises the following three subthemes:i) Research on technologies for prolonging the life of infrastructure
Regarding various construction materials in marine environments, wewill conduct research on the following: evaluation of long-term durability, understanding of deterioration mechanisms, and investigation of theprevention effects of protective methods for steel structures. Especially,
assuming that infrastructure is used overseas and on remote islands
in Japan, we will investigate material characteristics for durability improvement under severe environments and under conditions in which
low-quality material is used, and will investigate environmental-load
reduction, durability improvement, and environmental harmonization.
Regarding airport pavement, we will investigate methods for detecting
the stripping of asphalt mixtures, measures to prevent such stripping,
how the durability performance of airport pavement can be improved,and quick repair and rehabilitation techniques while construction quality, is still assured.
ii) Research on systems for inspecting and diagnosing infrastructure
We will conduct R&D on inspection and diagnosis techniques that utilize non-destructive and semi-destructive inspection methods and sensors, and unmanned investigation devices including ROVs. We will also
study operation methods for inspection and diagnostic systems, etc.
that leverage robots, drones, and other novel technology. Especially, we
will propose a health monitoring system that utilizes sensors and also anefficient inspection and diagnosis method specific to each component
and material type, and will also study efficient data analysis methods.
In addition, for piers, we will establish a scheme for selecting inspection and diagnosing methods according to the performance of structures to be evaluated and the accuracy of expected output.

•

•

•

•

•

•

Research Station, including exposure tests on steel pipe piles towhich anti-corrosion protective coating had been applied, and also
on hat-shaped sheet piles. We also conducted accelerated aging
tests and exposure tests to further elucidate the deterioration mechanism of petrolatum coating methods.
We evaluated the durability of concrete, in which low-grade aggregate (coral aggregate) and seawater as mixing water had been
used, and conducted exposure tests to develop a concrete-curing
technique using seawater. We also evaluated the durability of highly
corrosion-resistant reinforcing steel and surface coating materials
through exposure testing.
To study the effects of steel wire mesh in airfield concrete pavements,
we reviewed documents about the effects of steel wire mesh, thequantities in which it may be applied, available joint spacing variations, etc., and also conducted indoor experiments, etc.
We studied the workability of the filling material solidification method
for reinforcing existing caissons, and how their load-bearing and impact-resistant capacities would be affected by the improved strengthand the scope of improvement. Also, to enhance the technique forrepairing prestressed concrete components, we studied how their
durability would be compromised by chloride-induced corrosion, andhow their structural characteristics might be affected by repairs. We
then systematically organized our findings on those elemental technologies, and proposed a design workflow (draft) for repairing and reinforcing concrete structures. In addition, we conducted experimentson the expansion caused by delayed ettringite formation, and studied
and evaluated how it would be affected by water-shielding repair andrestraining reinforcement methods.
We conducted verification tests on monitoring by the inspection anddiagnosis system using IoT in addition, we studied the feasibility of
performing inspections using underwater drones and examined how
such inspection method could be operated.
We conducted experiments on ROVs for inspecting the superstructures of piers, and observed how their position measurement would
be affected by waves and other external disturbances. In addition, we
conducted on-site surveys using the ROVs while taking into accountthe waves and other site-specific conditions.
To advance the process of formulating preventive maintenance plansfor port and harbor facilities, we performed case studies on model
piled piers, while formulating renovation scenarios (selection of an
optimal renovation method and timing) based on which those piled
piers can be converted into a preventive maintenance, using LCC,
NPV, and LCCO2 as evaluation indicators.

iii) Research on maintenance and management systems for infrastructure
We will conduct accelerated deterioration tests of members of port
structures, investigate performance deterioration models which cover theentire lifecycle of structures, and validate such models through exposure
tests in actual environments and through on-site investigation. We will also
take into account the required properties and utilization of individual structures, budgets, and various limitations, and then suggest strategies ofmanagement of port-based and district-based groups of port structures.

Activities in FY 2019

• We used long-term exposure facilities to study how to predict chloride-induced concrete deterioration, the electrolytic protection characteristics of steel bars in reinforced concrete, and the concentrated
corrosion mechanism that affects steel materials. We also obtained
data on the durability of various wood materials and reinforced concrete that utilized recycled aggregate.
• We aimed to establish a method for predicting the deterioration ofprotective coating methods against corrosion. To achieve this goal,
we conducted continuous experiments at Hazaki Oceanographical09 PARI Annual Report 2020

ROV for inspecting pier superstructures and its experiment in a water tank(with wave and current)Research
Research
Themes
Themesand and
Activities
Activities
in FY
in2019FY 2019

2C

Research on Effective Use of Existing Infrastructure Facilities

Background and Objectives

Research and development comprise the following three sub-themes:i) Research on techniques to improve or renew existing facilities
We have already conducted research and development on improving existing facilities including deepening existing quaywalls. However, such improvements were made using techniques for newly-built
structures. Hereafter, we will investigate methods of evaluating groundcharacteristics, design methods, and geotechnical survey methods toimprove and renew existing facilities. In such methods, the construction
history, effects from neighboring structures, and other factors will betaken into account. We will also investigate ground evaluation methods
and geotechnical information databases, both of which cover residual
settlement and other phenomena, with the aim of long-term facility
maintenance and management.

• As there were no effective methods for checking the status of improved objects underground in 3D in cases where the risk of soil liquefaction is addressed by injecting chemical grout into grounds withununiform fine contents, we started examining methods for evaluating the quality of improved soils through geophysical exploration,and studied their effectiveness with the aim of establishing a suitable construction work management method. If such a method canbe established, it will be likely to enable more sophisticated quality
management during and after each construction work project andalso promote i-construction. To this end, we combined indoor tests,
on-site experiments, and numerical simulations to study the relation
between the physical characteristics of improved soils and the datum
measured during the geophysical explorations.
• We conducted scale model experiments to observe the plastic behavior of steel pipe piles and their bending behavior underground inorder to obtain basic data for high definition of performance regulation of piers. In addition, we made a flowchart indicating the basic
concept of design for improving sheet-pile-type mooring wharves.
• To visualize the microstructural features of original underground soils
on site, we developed and produced a compact X-ray CT scannerand a special drilling machine that could capture underground images in situ on site.
• We conducted numerical analyses for typical cross sections to examine how increasing the height of a bank would alter deformation ofits body, by changing conditons such as the height of raised dredgedsoil, distance between the temporary partition wall of raised bank andthe sea wall, structural and mechanical properties of the temporary
partition wall of the raised bank, countermeasures implemented on
the seawall itself, etc. To achieve the aforementioned objective, we
conducted a centrifugal test to verify simulation results and formulated a study method for raising a bank directly behind the seawall.

ii) Research on effective use and techniques of treating construction byproducts
We will investigate the following techniques regarding dredged soil:
improvement techniques to transform dredged soil into high-value added materials including composite soil, which provides habitats for benthic creatures, and solidified soil with high water permeability; and newvolume reduction techniques. We will also investigate durability whensolidified soil and slag composite soil are used in sea areas, the mechanical characteristics of composite ground materials containing various byproducts, crushable materials, and other contents, and methodsof evaluating and managing the quality of these materials.
iii) Research on management and utilization of waste disposalsites at sea
Regarding disposal sites at sea, technologies for seepage control
works for site development have been progressed. However, researchon post-construction utilization of such sites has not been conducted.
Therefore, we will investigate the following which are necessary for utilization: foundations, construction methods, effects on impermeable
layers, management methods of the internal water level at low cost,
techniques to detoxify waste before land reclamation, and the mediumto long-term strength and elution characteristics of solidified soil.

Development of technology for enhancing the capacity of a dredged soil disposal site
Top: centrifugal test, bottom: numerical simulation

PARI Annual Report 2020 10

Research Themes and Activities in FY 2019

Research Topics

Activities in FY 20194

• There is strong demand to improve the functions of existing infrastructure and use them effectively as possible. Requests include
measures to handle increasing cargo volume and larger ships andvessels, diversification of airport functions, and countermeasures
to deal with existing facilities which can no longer be used due toincreased external forces and other reasons. In addition, regarding
waste disposal sites at ports which accept industrial and non-industrial waste, there is social demand for the highly effective use of them.
On the other hand, it has become difficult to secure disposal sites
which accept soil dredged from water channels for shipping routes.
Accordingly, it is necessary to prolong the life of soil disposal sites.
• Therefore, we will develop the following: techniques to improve
the functions of existing infrastructure and to renew and efficiently
change the intended use of existing infrastructure; techniques to reduce or effectively utilize construction byproducts; and techniques toeffectively utilize waste disposal sites at ports.

Research Themes and Activities in FY 20193A

Research on Development and Utilization of Oceans

Background and Objectives

4
Research Themes and Activities in FY 2019

• Since the 1960s, the importance of marine utilization and development has been pointed out. Various approaches for this purpose
have been taken, but the progress remains inadequate. One of thereasons is the lack of infrastructure at sea as a hub. Therefore, marine hub ports should be constructed on remote islands including
Minamitorishima Island and Okinotorishima Island to promote marine
utilization and development.
• However, these remote islands are surrounded by severe sea wave
environment and severe sea climate for port construction which are
different from those of general ports in main islands. Further technological development is required to ensure smooth ship berthing,cargo-handling, and port construction.
• Therefore, in this research theme, we will make maximum use of previously accumulated knowledge regarding waves, sea-bed soils, port
structures, and port construction to construct ports on remote islands,
and will also promote marine utilization and development. Specifically,
we will clarify the characteristics of waves in isolated reef areas, andwill develop a new mooring system for ships. We will also develop
technologies for downsizing and reducing the weight of underwater
acoustic video cameras, as well as utilization and development.

••

Research Topics

Research and development comprises the following two subthemes:i) Research on port construction and management in remote islands
We will develop a numerical model for wave transformations on continental shelf boundaries and around isolated islands. We will also propose a technology to create calm water areas against wave propagationand long-period waves around isolated reefs. At the same time, we willdevelop a new mooring system applicable to remote islands to improvecargo-handling efficiency for ships.
ii) Research on infrastructure technology for utilization and development of oceans
We are trying to downsize and lighten underwater acoustic video
cameras, and will also develop an unmanned underwater construction
system to construct marine infrastructure. In addition, we will propose
environmental conservation technologies utilizing calcifiers.

Activities in FY 2019

• For the research on wave-controlling technology that can be applied to isolated coral reef sea areas, we conducted planar modelexperiments to study the characteristics of wave transformation that
normally occurs in isolated coral reefs, including how wave transformation occurs differently in relation to changing sea levels by tide,and also confirmed the reproducibility of the aforementioned phenomenon using high-resolution Boussinesq calculations. In addition,
we corrected the calculation result based on what we had learnedin those experiments as needed, and developed a tool that would
enable us to estimate and display the spatial distribution of waves
and currents over isolated coral reefs for various wave and current
conditions that normally arise.
• For the technological development of the new mooring system forships in ports, we suggested measures for resolving the previously
identified technical issues with the aforementioned system, for application to remote islands, and also summarized our research findings
obtained thus far.
• For the research on machine guidance technology used for underwater excavator, we conducted independent-element testing of moundleveling attachment in actual sea areas, to verify the usability of theadditional technology for remote operation. In addition, we evaluateda remote operation support system that integrated external measure-

11 PARI Annual Report 2020

•

•

•

ment sensors and the attachment into machine guidance, and tested
its usability by applying it to caisson mounds in Hirara Port.
For the development of the next-generation acoustic imaging system, we conducted experiments on dredging and bottom mud replacement works in actual work areas. As for acoustic video cameras, we applied detailed adjustments as needed for each work type,and removed the strong noise affecting the captured images originating from the power supply in order to improve the image quality. In
addition, as for the acoustic image viewing system, we created application software dedicated to each work type and also developeda viewer that updates the image along with the progress of the work
being conducted, which enabled us to determine when the current
seafloor height achieved the targeted value.
For the development of analytical methods applicable to the topographic dynamics of carbonate islands, we conducted GNSS surveys, photographic surveys using RTK-equipped drones, multi-beamsounding, aerial photography using a combination of visible light and
NDVI cameras, sediment and benthic organism sampling, seafloor
topography surveys using green-laser drones, and surveys of corallarvae. In addition, we analyzed factors that facilitate topographicalchanges, developed prediction methods, studied the relation between coral growth and the surrounding environmental conditions,and developed a method using deep learning that could automatically determine the distribution of reef-forming organisms and theirlevels of activity.
For the study of floating breakwaters equipped with a wave-power
generation function, we conceptually evaluated the configuration ofwave-power generation devices that would be integrated into floating breakwaters, and performed numerical calculations to examine
the optimal shape of such breakwaters while taking into account thewave-dissipating capability of the wave-power generation devices.
For the study of methods for calculating wave forces acting on offshore wind power plants, we evaluated the stability of the numericalcalculation using CADMAS-SURF while varying the mesh size andtime interval, so that we could calculate the wave force from the velocity and the acceleration of the water particles of progressive waves.
For the study of wave force calculation methods applicable to offshore wind power plants, we reviewed the current designs of offshore
wind power plants built on pile foundations, conducted repeated horizontal loading tests on piles set in saturated sandy ground in a large
soil tank, and also conducted repeated horizontal loading tests on
piles set in saturated clay ground at actual operation sites. Furthermore, we developed a numerical analysis code that could demonstrate the pile-driving (installation) process.

AI-powered automatic coral detection utilizing machine learning
1. Based on a sample image (top left), a correct (labeled) image(bottom left) is created.
2. Based on the labeled image, teaching data is created.
3. Machine learning occurs based on the teaching data.
4. Coral areas are automatically detected on the target image (right).

Research
Research
Themes
Themesand and
Activities
Activities
in FY
in2019FY 2019

4A

Research on Enhancement and Utilization of Coastal Ecology

Background and Objectives

Research and development comprise the following three subthemes:i) Research on coastal-ecosystem utilization
Regarding the ecosystem-based countermeasures against the impacts of climate change, we will conduct research on various phenomenathat help suppress climate change, such as carbon sequestration/storage by coastal ecosystems (blue carbon), and their absorption of CO2 in
the atmosphere, in various domestic and international sea areas. We alsoplan to develop related technology on a global scale. We will also develop
a technology to create coastal ecosystems which suffer less damage due
to earthquakes and tsunamis and which recover rapidly. Through suchtechnologies, we can continuously reap the benefits of the ecosystem.
ii) Research on the water-environment simulation and analysis in
inner-bay
Regarding the acquisition and utilization of environment observation
data, we will develop a new method for analyzing the marine monitoringdata obtained from the ferries, monitoring posts, etc. that are currently
in operation, and will also develop a new observation method that willallow us to effectively acquire certain types of environmental data forwhich conventional methods have not yielded sufficient results. We will
also re-analyze existing underutilized environmental data, and will use
multi-functionalized GPS wave-observation buoys to continuously observe areas for which environmental data has not been obtained. In addition, we will integrate weather/marine/ecosystem models and utilize inreal time the environmental observation data. Through these means, wewill develop a system which comprehensively predicts problems that frequently occur in inner bays, including red tides, blue tides, and hypoxia.
iii) Research on countermeasure technologies against sea oil spill
Regarding technologies for dealing with spilled oil, in addition todeveloping technologies to resolve conventional on-site challenges,
we will conduct new research and development on the following: oilgathering equipment loaded on next-generation oil-recovery ships;
and systems which comprehensively recover or treat oil and which canaddress large-scale oil spill incidents. In addition, we will establish an
information system for the risk management of oil pollution based on
simulation technology, understand the behavior and mechanisms ofoil spilled from dangerous facilities in waterfront areas due to natural
disasters including earthquakes and tsunamis, and conduct researchand development of quantitative prediction techniques and mitigation
techniques for spilled oil. Through such approaches, we will develop
innovative countermeasure techniques against oil pollution and improve
the ability to respond oil pollution.

• As for the study on the global dynamics model for estimating the CO2
absorption rates in shallow sea areas and inundation suppression effects, we developed and tested a global carbon circulation/ecosystem model and a wave and topography model, gathered topographic
and ecosystem data for global estimation, and performed GIS analyses of such data. We also conducted in situ surveys and experiments
on carbon dynamics in seagrass meadows, and performed analyses
using numerical models.
• For the creation of coastal topography and geo-design that help both
mitigate disasters and preserve ecosystems, we further improved
the integrated assessment and prediction method applicable to thecoastal ecosystems and geoenvironmental dynamics, elucidated
how earthquake-induced soil liquefaction, storms, and waves could
impact various types of benthic organisms in intertidal and subtidal
zones in terms of how they would be transported, floated, and buried,
and also their mortality rates. In addition, we evaluated and analyzed
the performance of various geoenvironments, including recycled soil,
to resist erosion and be used as a habitat by organisms.
• For the research on cross-sectional observation and analysis of atmospheric and oceanographic issues at bay mouths, we monitored
wind conditions in the atmosphere and facilitated development of
the cross-sectional observation system. In addition, we continued
steadily with marine observation activities, examined the feasibilityof applying satellite data to bay-mouth monitoring, and conducted
on-site observations.
• For the dynamic analysis of macro-organisms in coastal ecosystemsimulations, we created a code based on the formulation work done
during the previous fiscal year, implemented the code in the Ise Bay simulator, organized data gathered during on-site observations related tocurrent quantities, etc., and compared the data to the simulation results.
• For the development of technology to improve the functions of ecosystems in seagrass meadows, we obtained data on the fish community by utilizing environmental DNA, for which technical innovation has been advancing in recent years. In addition, we conducted
feeding experiments on the fauna inhabiting seagrass meadows andassessed their value as food in order to evaluate the function of seagrass meadows as feeding grounds for fishes.
• For the numerical analysis of coastal currents using current simulation and data assimilation, we conducted numerical experiments
in rectangular model sea areas, and verified that data assimilation
can be done by using a method of adding noise to the boundary
conditions to create their ensemble. In addition, we conducted data
assimilation using actual water temperature data measured in Tokyo
Bay and demonstrated that the water temperatures were correctedso as to approach the measured values.
• As for R&D on improving next-generation technology to mitigate oil pollution, we conducted model experiments to explore oil-gathering methods that might be suitable for adoption by next-generation oil recovery
equipment, which involved using pressurized water jet suction and an
excess water recycling system. In addition, we upgraded the networkadaptive oil movement prediction system to better estimate how marine oil spills are transported by the water. Furthermore, we studied amethod of controlling oil spills using self-extracting bubble curtains.
Top-down control
Bottom-up control

Organic sestons, detritus, algae, etc.

Study of prey organisms in a seagrass meadow

PARI Annual Report 2020 12

Research Themes and Activities in FY 2019

Research Topics

Activities in FY 20194

• Rich ecosystems in coastal zones include tidal flats, seagrass meadows, and coral reefs. Coastal zones are valuable places for the global
environment. However, during the era of rapid economic growth,
intense socio-economic activities caused the deterioration of water
quality in coastal inner bays and enclosed waters, resulting in ecosystem damage. Thanks to subsequent countermeasures, water
quality has gradually been improving in some coastal zones; however, recovery of the coastal zone environment including ecosystems
remains a formidable challenge.
• On the other hand, new challenges include the utilization of coastalzone functions for mitigating climate change, as well as countermeasures against large-scale oil spill incidents from maritime industrial
complexes and other facilities.
• Therefore, in the themes of this research, we will conduct researchand development with the following goals: further restoration of thecoastal zone environment, coastal zone utilization for climate change
mitigation, and establishment of technologies to counter large-scale
oil spill incidents.

Research Themes and Activities in FY 20194B

Research on Coastal and Estuarine Processes

Background and Objectives

4
Research Themes and Activities in FY 2019

• PARI’s research activity of littoral drift was started to examine thecritical water depth of sediment movement for harbor planning. Now,
prevention methods against sedimentation and also siltation are proposed. However, in Japan, sedimentation and siltation are still progressing in some ports, and in other countries which aim to expand
their infrastructure overseas, a much greater amount of siltation thanin Japan is projected. Countermeasures against such sedimentationand siltation problem have been inadequate.
• On the other hand, beaches are valuable as they provide protection,
environment and utilization functions. However, the area of beaches
has been decreasing since the era of rapid economic growth, and is
still shrinking at a rate of 1.6 km2 per year. Various countermeasures
have been taken to prevent such coastal erosion, and as a result,the beach area has increased at some coasts. Nevertheless, global
warming is expected to cause more severe coastal erosion. In addition, when remote islands and overseas are taken into account, it isimportant to maintain not only beaches but also coral-reef coasts.
• Therefore, in the themes of this study, we aim to maintain the following under future climate change: natural coastline geometry including beaches, mangrove coasts, and coral-reef coasts; and artificial
coastline geometry including navigation channels and harbor basins,
which support logistics. We will also estimate changes in coastalerosion and sedimentation phenomena assuming the progress ofglobal warming, and then propose countermeasures against thosechanges. Also, we will clarify siltation processes in the estuaries oflarge rivers, mangroves and intertidal zone in the Asian countries, andthen propose countermeasures against such phenomena.

Activities in FY 2019

• For the development of a method for predicting beach morphologicalchanges along with climate change, we used the shoreline change
model, which has been developed based on the observation data obtained at the Hasaki coast, and applied it to Omotehama Beach andOcean Beach. In addition, we started organizing the beach morphological change data in France and the future scenario data for predicting the future coastal change in collaborating with French researchers.
• As for observation at the Hazaki Oceanographical Research Station and the development of a coastal topographic change prediction model, we continuously conducted on-site observation of wind,
waves, currents, and topographic changes at the Hazaki Oceanographical Research Station. In addition, we performed calculations
to estimate topographic changes that would arise around structures,using the topographic change prediction model.
• As for the study on the transportation of sediments around estuaries
and their deposition processes in navigation channels and turningbasins, we developed and applied a numerical model that can simulate the sediment transport caused by waves and tidal currents toactual coastal areas in Java Sea, Indonesia. In addition, we examinedthe dynamic characteristics of fluid muds, which have been observedin the Java sea and the Niigata Port, and the prevention methods forminimizing harbor siltation with the fluid mud.
• As for the applicability of airborne laser bathymetry for topographic
monitoring in coastal areas, we studied survey methods to reduce
data losses caused by turbid seawater and white foam. In addition,
we developed a data reading program that could directly analyze
waveform data of laser reflection intensity.

Research Topics

Our researches and developments for coastal protection and maintenance of waterways and mooring basins are as follows:
We will analyze long-term measurement data of the Hasaki coast andconduct short-term, intensive, on-site observation of how beaches respond to different sea levels. Through this, we will understand beachresponse mechanisms to sea level rise, and will develop methods ofpredicting future beach morphology. We will take into consideration thespatial scale of not only the Hasaki coast but also global, and predict
long-term coastal changes (including natural sand coasts, sand coasts
protected by structures, coral-reef coasts, and pebble coasts) alongwith variations of coastal disaster risks. In addition, we will develop
hybrid beach-maintenance methods, which minimize structure volume
and actively introduce sand bypasses, and propose effective beach
maintenance methods that account for the disaster risks.
Regarding sediment transport which accompanies port utilization, we
will expand the scope of our research to include estuaries of large rivers, mangroves, and intertidal zones over-seas. Then, we will develop
monitoring method for topographic change which address regional
characteristics and understand the dynamics of topographic changes.
In addition, we will examine strategies to reduce siltation and sedimentation and will develop the efficient maintenance methods of navigation
channels and harbor basins as well as conservation of the surrounding
environment of port and harbor facilities.

Calculation of currents with and without a submerged breakwater, and topographic change (with oblique waves with a height of 1 m and a cycle of 6 s)
Left: with a submerged breakwater installed on the seabed 2 m below sea level,with its top surface 1 m below sea level
Right: without any submerged breakwater
Top: Currents (arrows) and the mean sea level (light blue indicates elevation)
Bottom: Topographic change (red indicates areas of erosion)

Application of the sediment transport model around the Patimban Coast,
Indonesia(Left) Simulated tidal current field(Right) Simulated wave field (arrows indicate wind direction and velocity; colors
indicate significant wave heights)

13 PARI Annual Report 2020

Fundamental
Fundamental
and and
Exploratory
Exploratory
ResearchResearch
Fundamental Research in FY 2019

The fundamental research of waves, beaches, ground, earthquakes,
environments, etc., is the basis of every study conducted by PARI, andtherefore we are actively working on clarifying principles and phenomena, such as the mechanisms of natural phenomena and dynamic behavior of the ground and structures.
Research theme (Fundamental research)

2

Investigation of earthquake disaster3

Development of estimation method for near-fault strong groundmotions

4

Study on the evaluation and analysis of liquefied ground behavior andeffective countermeasures under sequenced earthquake motions

5

Study from geotechnical view-point on stability evaluation methodof coastal structure subjected to high waves

6

Development of the estimation method for local scour aroundcoastal structures due to tsunami

7

Elucidation of oceanographic phenomena based on central
processing and analysis of observation data8

Evaluation of longterm durability of concrete, steel and various
materials based on exposure test

9

Evaluation of applicability of sustainable materials in the marine
environment

10

Development of the performance evaluation method in protective
coating for marine structures

11

Evaluation of the durability of various materials under severe
environments

12

Study on process leading to rupture of pier structure for highdefinition of performance regulation

13

Enhancement of accuracy of method for evaluating mechanicalproperties of composite geomaterials based on microstructuralfeature14

Development of analytical methods for the topographic dynamics
of carbonate islands

15

Elucidation of the horizontal resistance characteristics of pile foundations
for offshore wind power plants under various fluctuating loads

16

Validation of the newly developed global dynamic model for the
projection of atmospheric CO2 uptake rate and inundation control inshallow coastal ecosystems

17

Cross-sectional observation and analysis of atmospheric andoceanographic issues at bay mouths

18

Analytical study of macro-organisms dynamics on a coastal
ecosystem simulation

19

Development of the methods for increasing ecosystem functions ineelgrass meadow

20

Developing future projection model of coastal change in the context
of climate change

21

Observation of coastal phenomena at HORS and developmentof numerical simulation of topography change for port andsurrounding beaches

22

Study on sediment transport in estuary and deposition process innavigation channel

23

Study on applicability of airborne laser bathymetry for topographic
monitoring in coastal zone of sea shore

PARI Annual Report 2020 14

Fundamental and Exploratory Research

Strong motion earthquake observation in port and airport area

Development of estimation method for near-fault strong groundmotions• When a large crustal earthquake accompanies either a large slip near
the earth’s surface or a surface fault trace, ground motions arisethat contain permanent displacements in the near-source regions.
Ground motions containing such permanent displacements are often
referred to as “fling steps.” When the 1995 Hyogo-ken Nanbu Earthquake occurred, the ground motions observed in Kobe City did notcontain significant fling-step components. However, during the 2016
Kumamoto Earthquake, the rupture of the fault reached the earth’s
surface, and significant fling-step components were observed in
Komori, Nishiharamura, etc. near the fault. For those fling steps observed during the 2016 Kumamoto Earthquake, the rise time was as
small as 2 s and they could have caused a significant response to
structures. This highlighted the importance of fling steps once again.
• When calculating ground motions containing fling-step components,
it is necessary to use a method that can precisely handle the boundary conditions at the free surface in order to accurately consider thedifference in permanent displacement between the hanging walland foot wall sides. The discrete wavenumber method is one suchmethod: it allows precise calculation of ground motions for a halfspace or a layered half-space. However, when applying the discrete
wavenumber method to near-fault ground motions, various factorsthat affect the calculation result must be considered, one of which isthe subfault size.
• In some of previous studies to verify the applicability of the discrete
wavenumber method to near-fault ground motions containing flingstep components, the results of the discrete wavenumber method
were compared with analytical solutions for the permanent displacement. However, there have been few cases where analytical solutions
were obtained for displacement waveforms including the processthat leads to permanent displacements. Hence, such verification bycomparison with analytical solutions for displacement waveforms
themselves has been little studied.
• Therefore, in this study, we used the analytical solution obtained by
Masuda and Hikima, which is one of the few analytical solutions available as described above, to verify the effectiveness of the discrete
wavenumber method for calculating near-fault ground motions. During this study, we examined the required subfault size among otherconditions in order to achieve high-precision results. The aforementioned analytical solution pertains to ground motions for an elastic fullspace when a simultaneous slip occurs on a circular fault; it pertains
to displacement components parallel to the slip direction at receivers
along the central axis of the circle.
• This study revealed that using subfaults as small as 0.5 times the fault
distance would yield sufficiently precise results. The figures below
indicate the resultsof calculating displacement waveforms at distancesof 10,000 m, 1,000
m, and 100 m froma circular fault witha radius of 1,000
m, using a subfault
size of 50 m. Black
traces indicate theanalytical solutions
and red traces indicate the results
obtained using thediscrete wavenumber method; theyagree to each other
Comparison of displacement waveforms at distancesquite well, indicatof 10,000 m, 1,000 m, and 100 m from the fault
ing good calcula- Black traces indicate the analytical solutions and redtion accuracy with traces indicate the results obtained using the discrete wavenumber method
these conditions.

51Cases of Fundamental ResearchFundamental
Fundamental
andandExploratory
Exploratory
ResearchResearch

5
Fundamental and Exploratory Research

Elucidation of oceanographic phenomena based on central processing and analysis of observation data
• Since 1970, PARI has been constantly handling the routine work ofcentrally processing and analyzing the observation data obtained
through the Nationwide Ocean Wave Information Network for Portsand Harbours (NOWPHAS). As the risk of climate change intensifies, itis crucial to continue performing the work well, and also to provide information that is closely related to works at ports, harbors, and coasts.
• To achieve these objectives, we perform central processing and analysis of observed oceanographic data in this research. More specifically,
we will provide quick and final analysis on wave data observed at eachobservation station, summarize the wave statistical analyses in the Annual Report on NOWPHAS, and also store the tidal level and wind data.
• In FY 2019, we performed statistical analyses on the wave data obtained during 2018, and summarized the results in the Annual Reporton NOWPHAS. During this year, the highest significant wave was
updated at six observation stations; these are three coastal seabedwave gauges at Ise Bay, Shionomisaki, and Kobe as well as three
GPS-mounted wave buoys off the coasts of Kaiyo in Tokushima,
Cape Muroto in Kochi, and Hyuga in Miyazaki. Each of these locations set the new record because of the typhoons (Jebi and Trami)that made landfall in the Kinki region in September 2018.
• We will continue with our work of producing the Annual Report on
NOWPHAS, analyzing significant tsunami and wave events, andimproving related data processing and analysis methods, in order
15 PARI Annual Report 2020

to positively contribute to facility design and disaster prevention at
ports, harbors, and coasts.
Annual-meansignificant wave height

Annual-meansignificant wave period

Annual-maximum
significant wave height

Annual-maximum
significant wave period

Highest significant
wave height

Significant wave period
corresponding to highest
significant wave height

Significant wave height (m), period (s)Development of the estimation method for local scour aroundcoastal structures due to tsunami• Local scours behind breakwaters and around breakwater heads are
critical to the structural stability against a tsunami, but the amount of
the scour remains difficult to estimate.
• Therefore, in this study, we will elucidate the mechanism of local
scour by conducting hydraulic experiments, and establish a model
to estimate the amount of the scour by applying a particle-based
numerical simulation, etc.
• In FY 2019, we conducted a hydraulic experiment and numerical simulations to elucidate the phenomenon of local scour that will occur
around the head of the bay-mouth breakwater which is planned to bebuilt in Urado Bay, Kochi Prefecture.
• In this experiment, we installed a 1/40 scale model breakwater in ourlarge experimental wave basin and used a pump to reproduce tsunami.
We then measured the currents around the breakwater and the wave
forces acting on the caisson. A fixed floor was used in this experiment.
• Meanwhile, we used the tsunami and storm surge simulator (STOC) to
run simulations covering the large area extending from the tsunami wave
source area to Urado Bay, and calculated the current velocity distribution at the mouth of the bay, which would be the boundary condition of
the experiment. In addition, we found that the conventional calculation
method, which approximated the breakwater as the demarcation line,
tends to underestimate the current velocity and the amount of scour.
• Furthermore, to elucidate the characteristics of large eddies that occur around breakwaters, we performed 3-D calculations by applying
the particle-based numerical simulation method, PARISPHERE. The
results showed that the eddies around the breakwater head flowed
to a diagonally downward direction, from upstream to downstream.
• In addition, we conducted experiments to study the scour that occurs
behind a breakwater by a tsunami overflowing current, varying the
rubble mound shapeand the water level
behind the breakwater caisson. The experiments revealed
that the velocity ofthe overflow current
Breakwater head
Tsunamiincreases and bends
propagation
toward the caisson.
The bend current hit
Eddy
not the sandbed but
the rubble moundresulting in the suppression of the sandbed scour.
Experiment on currents around breakwater head

History of wave statistics at Ise Bay station of NOWPHAS(Highest significant wave height was updated for the first time in 14 years,
since observations started in 2002)

Evaluation of applicability of sustainable materials in the marine
environment• In order for us to achieve a sustainable society, it is desirable to reduce the usage of natural resources and cut CO2 emissions when
new structures (mainly concrete ones) are built. In addition, it is necessary to improve the performance of such structures and extend
their usable lifespans, to increase the safety margin for their timeinduced deterioration and ability to withstand natural disasters.
• One possible action to achieve these objectives is to utilize recycled materials (various slag aggregates, blast-furnace slag fine powder, fly ash,etc.), which is a clear and effective approach. However, there are few
instances where such approach is taken. Reasons why such action is
not taken often enough include the fact that performance requirements,
especially of structures made of non-reinforced concrete (i.e., blocks, superstructures of breakwaters, etc.), are not clearly defined, and also a lackof any established method for evaluating their long-term durability, etc.
• In addition, greater use of more environment-friendly construction
materials is desirable to reduce the negative environmental impacts.
However, few research projects have studied the environmental compatibility of various materials.
• To solve this problem, we will mainly tackle the following tasks.
• Multifactor evaluation of concrete performance involving recycledmaterials (workability, durability, etc.)• Organization of information on the performance requirements of concrete structures to be built at ports and harbors (mainly focusing on
non-reinforced concrete) and formulation of a method for evaluating
their long-term durability.
• Evaluation of environment-friendly materials (especially recycled materials) (While most previous studies focused on evaluating durability,
we will adopt a more comprehensive approach that also considers
environmentally negative effects (CO2 emissions, etc.).)Caisson (RC) is simulated

Parapet (non-reinforced) is simulatedExperiment on concrete made of high-density recycled aggregate (copper slag fine aggregate)(The concrete was produced at an actual plant and then transported and placed using a concrete pump)Indoor test

Marine exposure test

Comparison

Accelerated evaluation of chloride ion permeability of concrete utilizing blast-furnace slag fine powder (Comparison between indoor and marine exposure tests)

Fundamental
Fundamental
and and
Exploratory
Exploratory
ResearchResearch

Compression test on a simulated specimen having theidentical particle structure• A compact X-ray CT scanner and an excavator were developed andproduced in order to capture images of the soil microstructure ofground on site.

Numerical simulation of a pile-driving process(shear strain distribution and axial symmetry analysis)

Analytical study of macro-organisms dynamics on a coastal ecosystem simulation• Inner bays in Japan such as Tokyo Bay and Ise Bay experienced
industrial development and population growth during the post-war
period of high economic growth, which caused large amounts of nutrients to be transported from rivers into those inner bays, causing
eutrophication. Although the regulation on aggregate amount thatwas subsequent enforced improved the situation to some degree,
the decreasing amount of fish caught in the inner bays remains a
problem, the root cause of which is yet to be identified.
• The objective of this study is to simulate fish dynamics by integratinga fish ecosystem model into the Ise Bay simulator comprised of acurrent model and a lower-trophic-level ecosystem model.
• We developed a fish ecosystem model that could be run on the Ise
Bay simulator, and performed calculations to simulate fish dynamics
present in Ise Bay. Application of this model not only allowed us to
produce short-term results but also prove that it could perform calculations for whole years.
• This model is also applicable to other inner bays besides Ise Bay, andis expected to play an important role in fishery resource management
in various sea areas. For example, if a coastal sea area is to be developed and there is a fish species that uses the sea area only during a
specific season, we could create a work schedule to avoid disturbing
the fish during that season, and manage the overall work process inconsideration of the creatures and the environment that could be affected by the work.

Large quantity

Compact X-ray CT scanner

CT image of gravel (grain diameter of 2 to 5 mm)

Elucidation of the horizontal resistance characteristics of pile foundations for offshore wind power plants under various fluctuating
loads• Offshore wind power plants that are built directly on the seabed are
subjected to a variety of variable loads simultaneously for extended
periods, including wind, waves, earthquakes, etc. As each such variable load has a unique load amplitude, frequency band, number ofrepetitions, acting position, etc., the horizontal load affecting pilefoundations also consists of complex factors.
• In practice, the beam spring model in which the lower ends of piles
are fixed has been mostly used. However, as it is unclear whether
large-diameter piles could exhibit a similar resistance mechanism, thenon-linear ground spring model that is used cannot demonstrate thedeformation characteristics of ground that are manifested when subjected to repetitive loads. In addition, as it has not yet been clarified
the change of mechanical properties of ground during pile-driving, atpresent we must treat ground as virgin ground for design purposes.

Small quantity
February

April

June

AugustOctober

December

Simulation of distribution of adult Japanese anchovy(Engraulis japonicus) population• We will attempt to improve the calculation precision using a parameter tuning system. It is also important to accumulate data on the existing fish species utilizing fish-finder data, environmental DNA, andother related technology.
PARI Annual Report 2020 16

Fundamental and Exploratory ResearchParticle structure of thenumerical analysis model• Therefore, the objective of this study is to evaluate bearing capacity
while taking into consideration the history of pile-driving and externalvariable loads for offshore wind power plant having a pile foundation.
• During this fiscal year, we produced test equipment that can apply
horizontal loads to the piles, utilizing the large soil tank experimentplanned for execution in the next fiscal year, and also developed anumerical analysis code that can simulate the pile-driving process.

5

Enhancement of accuracy of method for evaluating mechanical properties of composite geomaterials based on microstructural feature• Geomaterials with different grain size distribution, particle shape, andother micro-structural features exhibit various mechanical properties
due to those features. In addition, even if soil specimens are sampledfrom the same geological stratum or prepared in a similar manner, thetest result may vary depending on their micro-structural differences.
Therefore, evaluating the effects of such micro-structural features willlead to advances in methods for evaluating the mechanical propertiesof the ground. In the conventional geotechnical investigation method,
undisturbed samples (i.e., cores) are taken from the original ground,after which various types of laboratory tests must be performed tomeasure their properties, etc. depending on the purpose. On the other
hand, if it were possible to use an X-ray CT scanner to acquire imagesof the micro-structural features of the ground, perform CT image andnumerical analyses, and conduct simulated soil tests using 3D printing
technology, it would enable the evaluation of the various mechanicalproperties of the core samples, which would be highly useful in practice.
• We performed uniaxial and triaxial compression tests on simulated
specimens created using 3D printing representing the particles andtheir sedimentary structures, and confirmed that they exhibited a
granular ground behavior resembling a ground.
• We applied the original data (shape and location data of each particle) on the simulated specimens as a numerical analysis model andattempted to reproduce the compressing movement.

Fundamental
Fundamental
andandExploratory
Exploratory
ResearchResearch
Developing future projection model of coastal change in the context of climate changesuch as the thickness measurement of steel pipe piles. Therefore,are expected to occur due to climate change, the beach morphology• We captured serial images on a steel pipe pile but were unable to

the risk of coastal disasters with a long-term view and to devise ap-

ment. Possible causes of this failure might be the less distinctive fea-

beach morphology with sufficient precision.

in the water that prohibited us from acquiring clear images, and thearound the world and develop a model that can predict future shore-

and prevented it from capturing images stably.

• In response to the rising sea levels and changing wave climate that

underwater drones might contribute to the labor-saving and effective
inspection and diagnosis.

at the end of this century will change drastically. Hence, to manage

generate a 3D model from images within the scope of this experi-

propriate countermeasures, we must be able to predict the futuretures acquired from each image, the murkiness and floating objects• In this study, we use observation data acquired from various beaches

waves and tidal currents that constantly shook the underwater droneline changes caused by climate change.

• In FY 2019, we applied the shoreline change model to Hasaki Coastin Ibaraki Prefecture, Omotehama Beach in Aichi Prefecture, and5

Ocean Beach in California, U.S.A. to check the model’s reproducibili-

ty. While the precision of the reproduction achieved by our model was
fairly good, the model parameters need to be made more generally

Fundamental and Exploratory Research

applicable. We will endeavor to resolve this issue in order to better
predict global beach morphological changes in the future.

Image of an underwater drone capturing images of structural components

Development of a sediment transport model that considers the 3D
dynamics of fluid mud• In ports and harbors located near estuaries, siltation (deposition ofmud) in shipping routes and basins could pose an issue in some cir-

cumstances. Therefore, it is important to develop a sediment trans-

port model that can accurately predict mud transport processes for
efficient maintenance and management of ports and harbors (e.g.,

dredging shipping routes and basins). It has been reported that thefluid mud formed on top of the consolidated bed affects the result of

acoustic sounding using multibeam sonar, etc. Therefore, we mustalso understand and predict the formation processes of fluid mudthat occurs with the accumulation of suspended mud. In this study,
Shoreline changes hindcasted by the model(Top: Hasaki Coast, middle: Omotehama Beach, bottom: Ocean Beach)

we developed a sediment transport model that can consider the ver-tical structure of high-concentrated mud including fluid mud and theflow structure depending on the mud concentration.

Exploratory Research in FY 2019
In FY 2019, exploratory research projects based on ingenious and/or advanced ideas that could potentially lead to new research fields for
PARI in the future were carried out.

A basic study on application of underwater drone and 3D data forinspection and diagnosis of marine structures• We successfully simulated the formation processes of fluid mud andthe flow structure depending on the mud concentration, by imple-

menting into the model the following key factors for simulating the

movement of high-concentrated mud: (i) flocculation of mud particles
and hindered settling of high-concentrated mud; (ii) buoyancy effectcaused by the mud concentration gradient; (iii) self-weight consolida-tion of fluid mud; and (iv) non-Newtonian fluid movement of fluid mud.

• In this study, we conducted an on-site experiment on existing underwater drones, 3D data, etc. to examine the applicability of them andto identify issues that must be addressed, with the aim of developing
an efficient and effective inspection method for the underwater components of marine structures.

• As underwater components of structures are generally covered bymarine creatures, we found it difficult to visually check the conditionof components only with the underwater drone. However, we found it
possible to apply the underwater drone for the preliminary inspection,
which is to determine the area where to perform detailed inspections
17 PARI Annual Report 2020

Simulated mud concentration, flow velocity, and vertical eddy diffusivity(Numerical configuration: initial concentration as indicated in the legend,depth-averaged flow velocity of 0.2 m/s, after one day)

Fundamental
Fundamental
and and
Exploratory
Exploratory
ResearchResearch(Left) New high-precision bi-directional shear test equipment developed inthis study(Right) Relation between two types of energy components and the number ofrepetitions of shear loading which caused re-liquefaction

Challenging research toward building infrastructure in the deep sea:
Evaluation of the physiochemical stability of concrete in the deep sea• As Japan’s territorial oceans and exclusive economic zone (EEZ) arearound 12 times larger than its territorial land area, the country’s ability to utilize its deep-sea resources is expected to radically improveits global competitive advantage. While the types of concrete being
used to build marine infrastructure in shallow sea areas could be also
used in the deep sea, there is a risk that conventional concrete might
deteriorate faster in the deep sea.
• To address this issue, in this project we conducted experimental
studies focusing on two points, the physical damage caused by hydraulic pressure and the chemical deterioration caused by low-temperature sea water, in order to evaluate the physiochemical stabilityof concrete in the deep sea.
• As concrete is a porous material, it is susceptible to the movement ofliquid water through microscopic pores and resulting changes in the
stress distribution, which could cause physical damage. Therefore,
we developed new equipment that could withstand high hydraulicpressure (maximum 20 MPa at a water depth of 2,000 m) and capture
images of the internal structure of specimens using micro-X-ray CT
technology (Figure 1). The physical damage caused to the specimens
by the water pressure was evaluated, based on the image analysis.
• Cement paste was immersed in low-temperature sea water and thenthe progress of its chemical deterioration was observed. It was revealed
that rapid deterioration of the cement paste was found at low-temper-

Averaged AE energy

Loading equipment
for horizontal motion(Y direction)

Development of a real-time mapping system for indicating the degreeof damage to pier floor slabs, utilizing mobile cargo-handling machinery• Since the piers in ports are used for logistics activities, it is difficult tostop such operations to inspect the piers, both for economic reasons
and also for avoiding disruption to citizens’ daily lives, as large quantities of supplies are loaded/unloaded and transported every day.
• In this study, we obtained AE data from the operation of mobilecargo-handling machinery as it traveled regularly from one location
to another, and performed analyses for formulating a measurement
method for evaluating the degree of damage and developing a wayof automatically determining the level of damage by using data obtained from AE activities.
• For data measurement, we drove the vehicles around while setting
the area of damage or non-damage as a parameter. By using thedata obtained from multiple sensors (four or more in this project) to
detect the elastic waves that occur during such vehicle operation, we
identified the points of excitation where elastic waves originated fromthe damaged locations. We then categorized the obtained data into
several different clusters, and formulated a method for determining
the degree of damage. More specifically, we adopted k-means clustering, which is an unsupervised machine learning method, and used
it to conduct the cluster categorization using the feature amounts
extracted from those elastic waves. As a result, we found that by conducting the cluster categorization based on the feature amounts ofthe data obtained from the power spectrum (Figure 1), the cluster categorization could be done based on the degree of damage detected.
In particular, as shown in Figure 2, when we assumed the number ofclusters was four and applied k-means clustering, we could achieve
cluster categorization of varying degrees of damage that corresponded to the mean AE energy and the number of AE hits.
• In the future, we will study measurement methods that can take actualsite conditions into account, develop a system to be able to make realtime determination, and also research location information systems.

Power Spectral Density

Loading equipment
for horizontal motion(X direction)

Figure 1: CT image captured by the equipment
developed in this research project

Frequency (kHz)

Number of AE hits

Figure 1: Power spectrum

Figure 2: Cluster categorization result

PARI Annual Report 2020 18

Fundamental and Exploratory Research

Loading equipment
for vertical motion

ature sea water, and the mechanism of rapid deterioration was estimated on the basis of thermodynamic phase equilibrium calculations.

5

Analysis of the re-liquefaction characteristics of sand with a historyof various types of shear including multi-directional shear based on
dissipated energy• Most of the previous studies on how shear history affected the re-liquefaction characteristics only considered one direction under planestrain; few studies examined the shear history considering the multidirectional seismic motions.
• To investigate the re-liquefaction characteristics of sand subjected toa multidirectional shear history, we developed bi-directional shear test
equipment that could conduct simple shear in multiple directions. We
chose loading equipment with an electromagnetic clutch, of whicha gap on the loading axis is minimize, so that it could perform finerepetition and stopping operations in a precise manner. Further, thisapparatus hardly showed backlash when the loading direction was
reversed, which enabled liquefaction tests to be conducted precisely.
• To quantitatively evaluate the effect of various types of shear history
on the re-liquefaction characteristics of sand, we calculated an index
based on dissipated energy during shear loading from the relation between the stress ratio and the strain. This index was found to show arational relation to the re-liquefaction characteristics. This energy index can be divided into two types of component. The one enhanced
the re-liquefaction resistance of sand and the other reduced. We
found that the number of repetitions of shear loading which causes
re-liquefaction can be estimated based on the relation between these
two types of components obtained from the shear history.

Published Research Papers
Number of Peer-reviewed papers in FY 2019
Number of papers in Japanese

Number of papers in non-Japanese languages

Total

Rate of papers in non-Japanese language

48 (36)53 (22)111 (58)

47.7% (37.9%)* The above numbers contain proceedings that only reviewed the abstract. (Numbers in parentheses indicate the number of journals.)

Papers Published in PARI Reports in FY 2019
LanguageMonth/Year

58-1-1No.

Development of Analysis Method of Moored Ship
Motion in 3D Fluid Field

Yasuhiro AIDA, Katsuya HIRAYAMA

Japanese

August 201958-1-2Strong Motion Simulation with the Pseudo Pointsource Model for Intraslab Earthquakes

Atsushi NOZU, Yosuke NAGASAKA

Japanese

August 201958-2-1Development of Visualization Method of Inter-particle
Force Distribution by Using Mechanoluminescentcoated Particle and Its Application

Akihiko KONDO, Daiki TAKANO, Eiji KOHAMA, Richard J. Bathurst

Japanese

February 2020

Development of Seismic Improvement Method for Pile
Supported Wharf Utilizing Existing Pile

Akihiko KONDO, Eiji KOHAMA, Yasuhiro TAKAHASHI,
Hideki YOSHIDA, Kenji WATANABE, Hayato KOKUSHO,
Shun AMANO, Moemi OYAMA, Shohei NAGASE, Takao FUJISAWA,
Nobuyuki OKAJIMA, Tetsushi ABE, Masashi INOUE,
Tohru YOSHIHARA, Mutsuro TSUKUDA, Tomoyuki UEDA,
Noriyoshi HARATA, Naoya NAGAO, Shin OIKAWA

Japanese

February 2020

58-2-2Title

Author(s)6Papers Published in PARI Technical Notes in FY 2019
Published Research Papers

No.

Author(s)LanguageMonth/Year

Development of Hydro-Geotechnical Centrifuge PARI
No.1353
Mark II-R

Hidenori TAKAHASHI, Naruhiko FUJII,
Yoshiyuki MORIKAWA, Daiki TAKANOJapanese

August 2019

Development of a New Compaction Grouting Method
No.1354 with Improved Upheaval Control and Efficacy ofLiquefaction Countermeasures

Shinji SASSA, Hiroyuki YAMAZAKI, Takeshi KONISHI,
Masaki ADACHI, Takashi SHINSAKA, Kanji TAKENOUCHI,
Hiroki MOROHASHI, Hidenori SAITO, Hiroshi OKADA, Keita TAKADA,
Shingo WATANABE, Chikai KANEKO, Tadashi TAKAHASHIJapanese

August 2019

Physical Environment Concerning Hard Clam’s
No.1355 (Merterix lamarckii) Survival at Kashima-nada OpenSea

Shin-ichi YANAGISHIMA, Satoshi NAKAMURA,
Masayuki BANNO, Yukio YAMAZAKI, Hiromi HANZAWA,
Toru UDAGAWA, Koichi SUGIMATSU, Ryogen NAMBU,
Hideki SAWADA, Satoshi TAKEWAKA

Japanese

August 2019

Yosuke NAGASAKA, Atsushi NOZU

No.1356

Title

Annual Report on Strong-Motion Earthquake Records
in Japanese Ports (2017)

Japanese

August 2019

Annual Report on Nationwide Ocean Wave Information Koji KAWAGUCHI, Fumikazu SUEHIRO,
No.1357
Network for Ports and Harbours (NOWPHAS 2017)
Takashi FUJIKI, Hitoshi TAMURA

Japanese

August 2019

Validation of Third-generation Wave Models in Terms
No.1358
of Ocean Swells

Hitoshi TAMURA, Koji KAWAGUCHI,
Takashi FUJIKI, Fumikazu SUEHIROJapanese

August 2019No.1359

Proposal of Pile Connection Method with Precast
Superstructure for Port Pier

Yuichiro KAWABATA, Katsuya IKENO,
Ema KATO, Mitsuyasu IWANAMI

Japanese

August 2019No.1360

Examination of Accuracy of Photogrammetry of
Coastal Area by UAV

Shingo KAWAGUCHI, Kojiro SUZUKI, Naoki TSURUTA, Shota ASAHI

Japanese

November
2019

No.1361

Diversity Indices in Marine Invertebrates: Comparisonof Two Types of Sampling Efforts

Shinya HOSOKAWA, Kyosuke MOMOTAJapanese

November2019

Long-term Exposure Test of Concrete Using Surface
No.1362 Coating Materials and Epoxy Resin-coated Rebar in
Naha Port Road Bridge

Toru YAMAJI, Nobuyuki KINJOH, Jun TOMIYAMAJapanese

November
2019

Axial Resistance of Steel Pipe Piles Installed andNo.1363 Cemented to Bedrock by Piling Rig with Twin Coaxial
Rotary Head

Takaaki MIZUTANI, Masaaki KOJIMA, Kazuyuki MURAKAMI,
Hirofumi MIGITA, Haruhiro MARUYAMA,
Hiroyuki HASHIMOTO, Takefumi ISHIDA

Japanese

November
2019

Japanese

November
2019

No.1364

Model Test for Effect of Installation Process and Shape Keita NAKAMURA, Yusuke MOTOMIZU, Satoshi MATSUMURA,of Piles on Pullout Resistance of Open-Ended Piles
Takaaki MIZUTANI, Satoshi SHINGAI, Eiji OSHITA, Naoaki SUEMASA

Field Test on Validation Accuracy of Residual
No.1365 Displacement Measurement Method after Earthquake
for Mooring Facilities

Yosuke OHYA, Eiji KOHAMA

Japanese

February 2020

Study on Strength Evaluation Technique by Using
No.1366 In-situ Tests on Chemical Grouted Ground as aCountermeasure for Liquefaction

Takahiro SUGANO, Kouki ZEN, Naoaki SUEMASA, Yasuo KASUGAI,
Hiroyuki YAMAZAKI, Kentaro HAYASHI, Shun-ichi SAWADA,
Toshio ENDO, Takaki KATO, Hiroshi NAKAGAWA, Hiroyoshi KIKU,Emi YAMAGUCHI, Noriyuki FUJII, Kanae BABA,
Teruhisa FUJII, Keita TAKADA

Japanese

February 2020

A Study of Calculation Conditions of Data Assimilation
No.1367 for Flow Analysis of Closed Waters by Ensemble
Kalman Filter

Yoshitaka MATSUZAKI, Tetsunori INOUE

Japanese

February 2020

No.1368

Analysis of Lower Trophic Ecosystem Model and Fish
Catches Using a New Fish Ecosystem Model

Tetsunori INOUE, Takashi KOMURO

Japanese

March 2020

No.1369

Recent Findings in Concentrated Corrosion andCathodic Protection in Marine Steel Structures

Toru YAMAJI, Hiroto TADO, Yoshiyuki KAWASE,
Atsushi KOBAYASHI, Michio YOSHIDA

Japanese

March 2020

Hirotaka ITO, Eiji KOHAMA

Japanese

March 2020

Japanese

March 2020

Development of Displacement Measurement andNo.1370 Stability Evaluation Support System of Mooring
Facilities after Earthquake by RTK-GNSS
No.1371

Annual Report on Nationwide Ocean Wave Information Koji KAWAGUCHI, Fumikazu SUEHIRO,
Network for Ports and Harbours (NOWPHAS 2018)
Takashi FUJIKI, Hitoshi TAMURA

19 PARI Annual Report 2020

Public Relations
Annual Report, Technical Journals,
and Website

Port and Airport Technology Lecture
Aiming to present and disseminate the achievements ofinvestigations, research, and technical developments carriedout at PARI, we held a Port and Airport Technology Lecture inTokyo on October 11, 2019 in cooperation with the National
Institute for Land and Infrastructure Management, which wasattended by 150 participants.

Open House set-up

Other Facility Tours
Other than the Open House, we held 59 facility tours, with
1,833 visitors. We introduced PARI facilities and PARI-associated research to visitors from private companies, the government, municipalities, and educational institutions to broaden
understanding of PARI’s activities and the social importanceof researchers. We also carried out activities to increase understanding of disaster prevention, such as providing various
information on earthquakes and tsunamis.

Other Outreach Activities
Cooperation with Super Science High school (SSH) Projects
For first- and second-year students from Kanagawa Prefectural Yokosuka High School which is SSHs designatedby the Ministry of Education, Culture, Sports, Science andTechnology, we explained our studies and organized tours
to PARI’s facilities to enhance students’ interest in scienceand math.

Presentation by a PARI researcher

Port and Airport Technology Special Lecture in Region
Aiming to widely provide information on the research activities and achievements of PARI and collect information suchas research needs in each region of Japan, we held 4 lecture
meetings throughout Japan in cooperation with the National
Institute for Land and Infrastructure Management, Regional
Development Bureaus, and others, gathering approximately
600 participants.

Students listening to an explanation on test
specimens used in experiments

Port and Airport Research Symposium
We held the Port and Airport Research Symposium in cooperation with the National Institute for Land and Infrastructure Management in Yokosuka City on January 17, 2020,
which was attended by more than 100 people.

PARI Annual Report 2020 20

Public Relations

Lectures for the General Public

Open House
During the Open House event held on July 20 (Sat), 2019,
which was jointly hosted with the National Institute for Landand Infrastructure Management (NILIM), we held a variety ofdemonstration experiments including one titled “Let’s Feelthe Power of a Giant Tsunami!,” set up experiential areas
such as one titled “Let’s Observe Marine Creatures’ Functions!,” and arranged exhibitions
such as one titled “Let’s Learn
Using a Drone Simulator!” Theevent was attended by a total of
870 visitors.

7

The Annual Report 2019 (Japanese version) and the PARI Annual Report 2019 (English version),
which summarized the activities
in FY 2018, were produced asa record of achievements, andwere distributed to the parties
concerned and published on
PARI’s website.
Regarding the PARI Technical Journal, we selected special
articles for each study theme forevery issue to introduce utiliza- The PARI Technical Journaltion situations of study results
and PARI’s experiment and on-site observation facilities. Approximately 2,000 copies of the PARI Technical Journal were
distributed to approximately 1,600 places.
On PARI’s website, we provided various information on
events and news including PARI’s summarized information,achievements, facilities, symposiums on a real time basis; wegot approximately 130,000 accesses in this fiscal year.

Open House

Outstanding Research Activities
Awards for Papers and Others in FY 2019
Name

Award

Institution

Date

Remarks

Japan Society of Civil Engineering,
Japan Society of Civil
FY2018 Distinguished Paper
Engineers
Award

April 5, 2019

Studies on the cathodic
protection characteristics inseabed soil and the cathodic
protection design of the port steel
structures in consideration of thesoil reactivity

2

Yuichiro KAWABATA Senior Researcher,
Structural Mechanics GroupFY2019 the Commendation for
Science and Technology by the
Minister of Education, Culture,
Sports, Science and Technology(The Young Scientists’ Award)

Ministry of Education,
Culture, Sports, Science andTechnology

April 17, 2019

Research on control of concrete
expansion and deterioration
based on structural analysis

3

Takahiro NISHIDA Senior Researcher,
Materials GroupFY2018 Society of Materials
Science, Japan, Kansai BranchManager’s Award

Society of Materials Science,
Japan (public interest
incorporated association),
Kansai Branch

April 18, 20194

Yuichiro KAWABATA Senior Researcher,
Structural Mechanics Groupand two others

Ports & Harbours Associationof Japan, FY2019 Distinguished
Paper Award

The Ports & Harbours
Association of JapanMay 22, 2019

Development of technology
applicable to the pile-connection
areas of precast superstructuresutilizing the sleeve tube type
method5

Sayuri MATSUMOTO Head, Sensing and
System Technology Group
Kageyoshi KATAKURA Visiting Researcher,Sensing and System Technology Group
Tomoo SATO Postdoctoral Researcher,Sensing and System Technology Group
Muneo YOSHIE Senior Director for Research

Marine Acoustic Society of Japan
Distinguished Achievement Award

Marine Acoustic Society ofJapan (corporation engaging inspecified non-profit activities)

May 30, 2019

High-resolution audiovisual dataacquisition system

6

Yuri SUGIYAMA Researcher, Soil Mechanics
and Geo-Environment GroupFY2018 Japanese GeotechnicalSociety, Research Encouragement
Award

Japanese Geotechnical Society

June 7, 2019

Analytical investigation of
disturbance on seabed-sampled
soil specimens and its influence
on unconfined strength

7

Takahiro NISHIDA Senior Researcher,
Materials Group

Presentation Award

4th International Symposiumon Concrete and Structures for
Next Generation

June 18, 20198

Tomohiro KUWAE Head, Coastal andEstuarine Environment Research Groupand one other

FY2019Japanese Association for Coastal
Zone Studies, Publication andCulture Award

Japanese Association for
Coastal Zone Studies

July 19, 2019Blue Carbon: CO2 Uptake andCarbon Storage in Shallow
Coastal Ecosystems and Their
Utilization

9

Technical Emergency Control (TEC) Force,
Port and Airport Research Institute, National
Institute of Maritime, Port and Aviation
Technology

2019 Prime Minister’sCommendation to Contributors for
Disaster Prevention

Cabinet Office

September 20,
20192018 Dispatch of TEC-FORCE
following the Hokkaido Eastern
Iburi earthquake

10

Hidenori TAKAHASHI Head, Soil Stabilization
Group
Yoshiyuki MORIKAWA Director, GeotechnicalEngineering Department
and two others

Telford Premium Prize(Distinguished Paper Award)

Institution of Civil Engineers(ICE), U.K.

October 4, 2019Thirty-seven-year investigation ofquicklime-treated soil produced
by deep mixing method

11

Toshinari TANAKA Senior Researcher,
Robotics GroupEma KATO Head, Structural Mechanics
Group
Shuji NOGAMI Senior Researcher, Structural
Mechanics Group

19th Symposium on Construction
Robotics in Japan, Outstanding
Paper Award

Council for Construction Robot
Research (CCRR)

8

1Toru YAMAJI Director, Structural Engineering
Department
Kazuhide YONAMINE Researcher, Materials
Groupand eight others

Outstanding Research Activities

12

Shinji SASSA Head, Soil Dynamics Group

3rd Infrastructure Management
Award, Special Award

Six Ministries (Ministry of Land,
Infrastructure, Transport andTourism; Ministry of Internal
Affairs and Communications;
Ministry of Education,
Culture, Sports, Science andTechnology; Ministry of Health,Labour and Welfare; Ministryof Agriculture, Forestry and
Fisheries; Ministry of Defense)

13

Hitoshi TAMURA Senior Researcher, Marine
Information GroupFY2019 Hydrographic Technology
Encouragement Award

Japan Hydrographic
Association (generalincorporated foundation)

21 PARI Annual Report 2020

October 10,
2019

Field test of ROV equippedwith tele-operation assistancefunctions for inspection of
concrete pier superstructure

November 7,
2019

Method for reducing waves
passing through caisson joints tosuppress washout and collapseof seawalls and quaywalls and toextend the service life of port andharbor structures

February 27,
2020

Development of a wave
prediction system for oceanswells based on a coupled phasemodel

PARI Events
Active Commitment in International Meetings,
Workshops, and Other Projects
In December 2015, the United Nations General Assembly officiallydesignated November 5th, which has already been designated as Tsunami Prevention Day in Japan, as World Tsunami Awareness Day. Subsequently in 2016, the Goryo Hamaguchi International Award, an award
granted by the Minister of Land, Infrastructure, Transport and Tourism,
was inaugurated, to recognize those who have made significant accomplishments related to the prevention and mitigation of tsunami andother coastal disasters. On October 29, 2019, the award was given to
two recipients: Dr. Tomoya Shibayama, professor at Waseda University
and professor emeritus at Yokohama National University, and Dr. Ahmet
Cevdet Yalciner, professor at Middle East Technical University (Turkey).

Broad Research Exchange with Japanese andOverseas Research Institutes
To improve the quality and efficiency of research, we actively collaborated on research with domestic and overseas research institutes andsigned a total of 39 research cooperation agreements with 13 Japaneseand 26 overseas institutes as of FY 2019. Also during FY 2019, PARI
extended the research cooperation agreement it had executed with the
French Institute of Science and Technology for Transport, Development
and Networks (IFSTTAR) in order to continue with the mutual technicalcooperation between the parties in geotechnology and civil engineering.

Conclusion of Education and Research
Collaboration Agreements

Dispatching of Researchers to Various Technical Committees
We dispatched a total of 131 researchers to various technical committees organized by governments and other organizations to solve
technical issues concerning the execution of port, coastal, and airport
public works by national and municipal governments and local administrations. Including technical committees on improving ports, coasts andairports established by various institutions, a total of 316 researchers
were dispatched by PARI, and actively tackled technical issues facedby governments and other organizations.
Dispatching of Lecturers to Training Courses for Domestic Engineers
Training courses for national and other public service engineers areheld by NILIM. We actively participate from the planning stage and havedispatched a total of 34 researchers to 15 training courses as lecturers.
Providing Operational Support for Technical Standards for Ports,
Airports, etc.
Regarding technical standards for port facilities, our researchers
took part in technical committees set up by the Ports and Harbours
Bureau of the Ministry of Land, Infrastructure, Transport and Tourism.
Our researchers also gave lectures at NILIM, conferences, and seminars organized by other relevant organizations, and contributed to the
spread of technical standards. Regarding airport facilities, our researchers participated in various investigative commissions in preparation forthe smooth introduction and operation of technical standards for airport
civil engineering facilities.
Support for Evaluation of New Technologies
In response to a request of the Ministry of Land, Infrastructure, Transport and Tourism (including regional development bureaus), PARI offered technical support by dispatching researchers to the New Technology Utilization Evaluation Conference established by each organizationfor evaluating the practicality and applicability of the technologies to beregistered in the New Technology Information System (NETIS) in orderto promote the application of useful new technologies.

We signed agreements with national, public and private universities.
Under these agreements, PARI researchers serve as grad-school professors or take other positions at the universities. Under the graduate
school linking system, in which postgraduate students receive instructions at research institutions, we concluded collaboration agreementswith 12 universities including the Tokyo Institute of Technology, Nagoya
University, and Nagaoka University of Technology. In FY 2019, we dispatched 9 researchers as lecturers. We also dispatched a total of four
researchers to universities which are not under the graduate school linking system, including the Nihon University.

PARI Annual Report 2020 22

PARI Events

In May 2019, PARI representatives attended Coastal Sediments 2019held in Houston, Texas, U.S.A., which is an international conference onbottom sediment movement and topographic changes in coastal areas, to present their research findings on the medium-term topographic
changes observed on back shores, and gather information on various
research projects taking place overseas.
In addition, PARI hosted a seminar at the University of Transport andCommunications (UTC) in Hanoi, Vietnam in November 2019, on life
cycle management pertaining to marine structures. During the event,lectures were given on the electrolytic protection of concrete structuresfrom corrosion, etc., and participants actively exchanged ideas andopinions on the topic.

Dispatching of Researchers to Disaster Sites
As record rainfall occurred on August 28, 2019 mainly affecting Northern Kyushu and caused damage to bulkheads on the coast around Shimonoseki Port in the Sanyo region, PARI dispatched four researchers,
etc. (two of whom were PARI employees) to Shimonoseki Port, jointlywith the Ports and Harbours Bureau, MLIT and the National Institutefor Land and Infrastructure Management (Yokosuka), to investigate thedetails of the damage caused by the disaster.
In addition, the violent winds caused by Typhoon Faxai that passed
over Japan on September 9, 2019 caused a ship to collide into Hama
Road in Minami-Honmoku pier of Yokohama Port, and also the storm
surge driven by the same typhoon caused damage to the bulkheads
on the pier there, so PARI dispatched seven researchers to the site toinvestigate the damage to the bulkheads.
Furthermore, as Typhoon Hagibis made landfall on the Izu Peninsula on October 12, 2019, and the storm surge driven by this large andstrong typhoon caused damage to the bulkheads in the Kanazawa areaof Yokohama Port, PARI sent four of its researchers to the site for investigation.

9

A prize awarding ceremony and commemorative lecture of the
Hamaguchi Award (October 29, 2019, Tokyo)

Promotion of Administrative SupportJuly 2020

−Creating Technologies that Contribute to the World−

National Institute of Maritime, Port and Aviation Technology

Port and Airport Research Institute3-1-1 Nagase, Yokosuka, Kanagawa 239-0826, JAPAN TEL +81-46-844-5040 FAX +81-46-844-5072 URL http://www.pari.go.jp