LRRI 技術情報，Vol.2，No.2，pp.1-88，2024.3

気候変動に対する地盤工学的対応策
安原一哉（一社）地域国土強靱化研究所 代表理事
概 要
◆目的・主旨
気候変動を含めたサステナビリティに対する地盤工学的対応策の現状を紹介することによって、この方面の地盤工学の関心を高揚させることを目的とする。
◆話題の概要「気候変動における持続可能性への地盤工学的貢献」
安原一哉
サステナビリティのうち、気候変動に伴う地盤災害（特に、複合災害）に焦点を当て、現状の分
析と今後の対応策を展望した。加えて、IPCC 等の国際機関に対する貢献策も併せて提案した。
「丸太を用いた液状化対策による気候変動緩和貢献の事例紹介」
村田拓海
気候変動緩和策としての地盤災害対策への木材利用の可能性に焦点を当て、大規模分譲住宅地に丸太を用いた液状化対策工法を適用した事例と、その工事における炭素貯蔵効果を紹介した。
「産官学連携による地方都市における木材利用促進と社会貢献」
吉田雅穂
木材資源の豊富な地方都市の福井県における、産業振興、地域活性化、国土強靭化、気候変動緩和への貢献を目的として、産学官が連携した木材利用研究会の活動を照会した。
「気候変動における持続可能性に関する LRRI の活動」
安原一哉
地域国土の強靭化の課題のうち、気候変動に伴う地盤災害に焦点を当て、LRRI における過去 3
年間の取り組みを報告し、併せて、LRRI 会員の所有する関連の技術例を紹介した。
◆知見・結論の要点
SDGs のなかで取り上げられている“気候変動”に対する対応策（緩和策、適応策、緩和策と適応策の融合）の事例を紹介し、地盤技術もこのことに貢献することができることを示した。
◆知見の意義地盤工学が地域社会のサステナビリティにも貢献できる分野であることで認知を広げることができる。併せて、LRRI の認知の拡大にも繋げることができる。

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目 次
第Ⅰ編
1． CREST 2023 の概要 ・・・・・・・・・・・・・・・・・・・・・・・・・・3
2.

CREST 2023 WORKSHP 2 の概要 ・・・・・・・・・・・・・・・・・・・・7

第Ⅱ編
1. 「気候変動における持続可能性への地盤工学的貢献」 ・・・・・・・・・・・10
安原一哉，茨城大学名誉教授， (一社)地域国土強靭化研究所(LRRI)代表理事
2. 「丸太を用いた液状化対策による気候変動緩和貢献の事例紹介」・・・・・・・42
村田拓海， 飛島建設(株)， 副主任（博士）3. 「産官学連携による地方都市における木材利用促進と社会貢献」・・・・・・・55
吉田雅穂，福井県木材利用研究会会長，福井工業高等専門学校教授
4. 「気候変動における持続可能性に関する LRRI の活動」・・・・・・・・・・・74
安原一哉，(一社)地域国土強靭化研究所(LRRI)代表理事

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1．CREST 2023 の概要

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2. CREST 2023 WORKSHP 2 の概要

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2024.3

第Ⅱ編
1. 「気候変動における持続可能性への地盤工学的貢献」

Lecture Content◆ Background situations◆ Compound Event Importance◆Adaptation Strategies for
Climate change-induced Disasters◆Increasing Resilience against
Climate change-induced Disasters◆ Challenges for Increasing
Geotechnical Engineering’s Rolein IPCC

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安原一哉

2024.3

Background Situations

IPCC AR6:Change in Global Surface Temperature
Relative to 1850 - 1900

It is unequivocal that human influence has warmed the atmosphere, ocean and land. Widespread andrapid changes in the atmosphere, ocean, cryosphere and biosphere have occurred.
人間活動が気候システムの温暖化および広範で急速な気候変化をもたらしてきたことは疑う余地がない。

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2024.3

IPCC AR6:
Precipitation & Soil
Moisture Content• Many changes in the climate
system become larger in direct
relation to increasing global
warming. They include increases
in the frequency and intensity of
hot extremes, marine heatwaves,and heavy precipitation,
agricultural and ecologicaldroughts in some regions,
proportion of intense tropical
cyclones as well as reductions in
Arctic sea ice, snow cover andpermafrost.
• 熱波、豪雨、干ばつ、強い台風、北極海
氷・積雪・永久凍土などの損失といった気候システムの変化の多くは温暖化の進行とともに大きくなる。

Definition of Risk in IPCC AR5 and AR6

AR5 2014（第５次報告書）

AR6 2021（第6次報告書）

Risk in AR6 is also a function of response in addition to hazard, exposureand vulnerability in AR5. This means that mal-adaptation may increase risk.

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2024.3

Economic Losses,
Poverty and Disasters

1998-2017
UNISDRUNISDR: United Nations International Strategy for Disaster Reduction (before 2019)
UNDRR: United Nations Office for Disaster Risk Reduction (after 2019)

Recent natural disasters: Number of occurrences of events(a) Around the world(b) In Asia

世界，アジアともに水害，暴風，地震が中心

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2024.3

Numbers of Disasters per Type1998 - 2017
④Extremetemperature① Flood② Storm③ Earthquake⑥Drought⑤Landslide⑧Volcanic
activity⑦Wildfire⑨Massmovement

世界中では，災害発生数は，水害が50％弱を占める

Change of Disaster Characteristics
Markedly
decreased in Africa

Considerablyincreased in Asia

Asia has become the most vulnerable region to natural disasters.
（アジアが最も災害脆弱性が高い!）

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2024.3

Percentages by death

1990--2015 (25 years)

1990--2005 (15 years)(Present study)(adopted from Kokusho, T. (2005))

Statistical Data for Disasters from EM-DATThe Emergency Events Database(EM-DAT) has been maintained by theCentrefor
Researchonthe
Epidemiology of Disasters (CRED)
since 1988. The primary objective of
EM-DAT is to provide information to
support humanitarian action at thenationalandinternational
level,
enabling rational decision-making indisaster preparedness. The databaseoffersobjective,
evidence-based
information that can be used to assess
the vulnerability of communities todisasters, thus assisting policymakers
in setting priorities.

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2024.3

Number of Disasters by Continent

④

②

③
①

Occurrence by Disaster Type

③

③

①

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2024.3

Human Impact: Total Affected

④

②

③

①

Number of Affected
by Disaster Type
②

①

③
④
①

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Economic Losses by Continent

②

①
④

③

経済的損失は，GDP の高い国とGDP の低い国とも大きく，二極化している

Economic Losses by
Disaster Type

④

③

②

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①

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Human Impact: Total Deaths by Continent②①③④
死者数も，GDP の高い国とGDP の低い国とも大きく，二極化している

Number of Deaths
by Disaster Type

①

②

④

③

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2024.3

Japanese Situation2011 East Japan Great
Earthquake2015 Flooding in Ibaraki
2016 Kumamoto Earthquake2014 Debris flows in Hiroshima
2017 Flooding in northern Kyushu

2019 Typhoon-induced flooding
in Nagano2023 Torrential rainfall-induced
slope failure in Hitachi, Ibaraki

2018 Earthquake in Hokkaido

水害，地盤災害（含土砂災害）が多発している➉

Sediment Disasters
Caused by Intense Rainfall and Strong Earthquakes

Sediment disasters（土砂災害）are related more closely to torrential rainfall than to strong earthquakes.

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2024.3

Compound Disaster
Importance

What are compound disasters（複合災害）?
Climate-change
triggered
SLR

Vulnerable social, andhuman backgroundTyphoonCompounddisasterRainfall

Not NoclimateclimatechangechangeassociatedassociatedEarthq.

Vulnerable natural
background(b) Events and background forincreasing compound disasters

Overlapping of multiple phenomena
triggered by global warming
Overlapping climate change-associatedand non-associated phenomena＋

Overlapping vulnerable social and naturalenvironments and aged infrastructure－

GeodisasterLand sub.
Tectonic
Movem.

(a) Disasters caused by overlappingof multiple phenomena

Waterdisaster21－

Extremeevents2024.3

Compound Disasters and Chained Disasters（複合災害と連鎖災害）
Compound disasters（複合災害）

Climatic
event

ErosionTsunamiEarthquake

Nonclimatic
event

Landslides

Nuclear waste
contamination

Chained disasters（連鎖災害）

Flood

Land disturbanceClimate changeEast Japan Great Earthquake
The event of 2011 is a noteworthy
exampleCompounding Factors ➣ Magnifying, Intensifying and Widening

How can we make strategies forsecurity and safety?

Has the earth been getting worse?

Two Examples of Compound Disasters（複合災害の事例）
Climate-change
triggered
SLR

Vulnerable social,human background

CASE I

TyphoonCompounddisasterRainfallWater
disasterclimatechange
Not Noclimatechange
associatedassociatedEarthq.
Tectonic
Movem.

Geodisaster

Combined with
SLR and land
subsidence（海面上昇と地盤沈下の複合）

CASE II

Land
sub.

Combined
torrential rainfallwith earthquake

Vulnerable natural
background（猛烈な雨と地震の複合）

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CASE I:
Combined with SLR and land subsidence
Susceptible to undergo the impacts of flood andinundation caused by storm surge andoverlapping waves

Sea-level
rise (SLR)

Land
subsidence
Breakwater

Sea

Building
structureLand◆ There are many vulnerable low-lying coastal areas, such as
・Mega deltas (Niles, Ganges, Mekong)・Important coasts (Venice, New Orleans)

Objective Areas among Vulnerable Coastal Deltas(Chao Phraya Delta in Thailand, チャオプラヤデルタ，タイ国）☚対象地域

Relative vulnerability of coastal deltas (IPCC WGII, 2007)

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2024.3

Definition of Relative Sea-Level Rise (SLR)
Normal SLR(a) Typical variation of SLR with elapsed timein 2100 (IPCC, 2007)(b) Definition of relative sea-level rise (SLR)

Observational Prediction Procedures for Land
Subsidence (Murakami et al., 2004))

 S i  S P 0 1  exp  C R ti }

Case of Chao Phraya Delta, Thailand(adapted from Murakami et al., 2004)

 T 
S p 0  S f 2 exp  v 0 

 4 
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2024.3

Case study: Chao Phraya Delta, Thailand(from Murakami and Yasuhara, 2011).

(b) Contour map of the interpolated future(a) Contour lines of land subsidence in Chao Phraya
Delta (from Murakami et al, 2004).

and subsidence (from Murakami et al., 2004).

Assessing the Influences of Dual Effects of SLR and Land
Subsidence on Inundation Areas(from Murakami et al., 2011)(a) Inundation area caused only by sea-levelrise－(c) Inundation area caused by sea-level riseand land subsidence with estimation error

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CASE II:
Combined torrential rainfall with earthquake（猛烈な雨と地震の複合:2004年 新潟中越地震）

2004 Niigata
Chuetsu
Earthquake

Typical Example of Compound Disasters:
Niigata-Chuetsu Earthquake in 2004
（新幹線の脱線）（高速道路盛土の崩壊）

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Mechanism of Slope Failure Caused by
Earthquake and Abnormal Rainfall

⾧期にわたる降雨と度重なる余震を伴う大きな地震の複合➢
4000か所にわたる斜面崩壊

Mechanism of Slope Failure Caused by Earthquake
and Abnormal Rainfall (Nunokawa et al., 2007)
Earthquake
Hourly rainfall (mm)Hourly rainfall

Working rainfall

Working rainfall (mm)Rw = Σi 0.5i/TRi• Working rainfall Rw: Index of precipitation calculated using hourly reduction of
the influence of past precipitation（傾斜の緩やかな斜面の崩壊が顕著）

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2024.3

Adaptation Strategies for
Climate change-induced
Disasters

Climate Change Responses and Their Synergy（気候変動対応策と緩和策と適応策の融合）
Mitigation
GHG
・Capture・Storage・Effective utilization

Adaptation

Synergy of
Mitigation
and Adaptation【Carbon neutral】

Disasters
・Protection
・Accommodation
・Evacuation/
Relocation【Local Resilience
increase】

Challenging issues（期待される挑戦的課題）
Adaptation strategies are emphasized in today’s presentation because the strong focus has
been placed too much on mitigation including carbon neutral.

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2024.3

Strategic Situation of Climate Change Adaptationin Japan (by LRRI through Consignment by Ibaraki University)（茨城大学委託業務報告書（2023）による）

7%
Others①Centralgovernment②Localgovernment

36%

35%

③Private
sector22%442: Number of adaptationcollected from publication

7 fields of adaptation in Japan（適応策の７つの分野）
Citizen life
& urban life

Common & basic measures②Agriculture,

6%

livestock11%

forestry &fishery

Industry, energy

22%
Water

& economic activities
8%

environment& water③Health①Natural disasters

13%& coastal areas

resources
10%
Ecology

25%

5%

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2024.3

Categories of Adaptation to Natural Disasters（災害に対する手法のカテゴリー）
Modelling & analysis ofpresent situation, 6%
Economic
measures, 7%③空間＆インフラ計画①Technical③Space planning,measures,infrastructures,51%①技術的手法13%②社会的手法②Social●Technical measures are
predominant.
This is one of the characteristics inadaptation strategies in Japan.

measures, 22%

Increasing Resilience against
Climate change-induced
Disasters

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2024.3

Hazard, Vulnerability ,Adaptation, and Resilience（ハザード，脆弱性，適応＆強靭化）
Mitigation

ClimatehazardProgress of global warming

Vulnerability

External
force
Large gap
Aged
infrastructure

Developed
infrastructure

Resistance

Defensive force
Past(was predictable)

Present

Adaptation

Future(unpredictable)

Elapsedtime

Resilience shrinks vulnerability

from Komatsu et al. (2014)

A Successful Case Study in Bangladesh for Road
Embankment Using Jute (Matsushima et al., 2011)

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2024.3

An Example of Hard Mitigation Measure Adopted by Geosynthetics
and Cement (Yasuhara and Recio, 2007)
09,000

Vertical Deformation (mm)518,000
NumberNumber
of of
Waves
Waves

27,00036,000Nonwoven,dense sand

10

Nonwoven; Sewn together and Injected15
collapse
Injected withmortar20

Wave height 0.18m
Period 4 second

25
30

STABLE
collapse

Layers sewn
together

Nonwoven Geotextile, dense sand,
Non-Geo, loose sand, layers sewn together
Non-Geo, loose sand, injected with mortar(a) Test scheme
35
0

10

(c) Test results

20
time (hours)

30

40

The concept is “From Rigid
to Flexible Structures”➢減災対策(b) Model test equipment

From Reactive to Proactive Measures（事後保全から予防保全へ）

Good combination of reactive measures with proactive measures➣ equivalent to the “adaptive adaptation” concept

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2024.3

Green Infrastructure（グリーンインフラ）● Grey infrastructure
Concrete structure/ Geosynthetics ⇒ Protection● Green infrastructure
・CO2 absorption potential in plants ⇒ Mitigation
・ Biomass CCS (Recovery storage)
・ Utilization of thinned wood and bamboo◆ Synergy of grey infrastructure with green infrastructure
Must be an example of combination of adaptation and mitigation

Development of Used Tire Application
for Coastal Protection （古タイヤの有効利用）
SeasideLandside

Vegetation

Sea WallUsed tire structures for erosion
and scouring prevention
Hazarika and Fukumoto (2016): International Journal of Geomechanics, ASCE

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2024.3

Multi-protection Measures with Green--Grey Infrastructure
Synergy in Vietnamese Coasts (Yasuhara, 2016)（グリーンとグレーの融合による多重防御の例）(a) SandNourishment(b) Mangroves(c) Gabion

Multiple Protection Based on GGB Concept
Proposal in
Vietnamesecoast
ベトナム沿岸域での提案

UAV

事例

Mangrove
Dyke soil
mixedwith fiber& cement

Acceleration
sensorGrey-infrastructure（波消しブロック）➢波力を弱める＊グリーンを防護する

Green-infrastructure➢堤防を防護する＊CO2 を捕捉？

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Brown-infrastructure➢（堤防を強化する）

2024.3

Typical Example: Monitoring System for Slope Stability andEvacuation Using MEMS Sensors (After Saito, Ibaraki University)

Example as Soft Technology
for Increasing Local Resilience(After Saitoh, Ibaraki University)
Internet (IP) infrastructure

Kana-chanleft school at
3 PM.

Cloud server

Monitoring
using UAV

Local community・
Infrastructure

SchoolSchoolInformation
sharing Mobile
Sensing TAG

Sensing TAG

Transmissionof disaster
information

Hospital・ GPS (Location information)・ Acceleration (Health monitoring)・ Radiation (Small scintillation sensor)

Mobile(UAV, un-crewed aerial vehicle)

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Dual Approach of Adaptation:
Top-down and Bottom-up Approaches
Scientific knowledge

Public assistance（公助）

assistanceScience-based, Mutual（共助／協助）Natural Science
Oriented

Community-based
Human Science
Oriented
Self assistance（自助）

Local residents’knowledge & wisdom

Roles of Stakeholders

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2024.3

Some Keys for Overcoming Extreme & Catastrophic Disasters◆Scientific aspects➣ Uncertainty ➣ increase certainty◆Natural environment aspects➣Vulnerability ➣ strengthen resilience•◆Social aspects• ➣ Myth ➣ should not believe and produce myths•- Shinkansen （Japanese bullet train) should
never collapse•- Nuclear power station is safe
◆Human aspects• ➣ Unpreparedness, Negligence,•
Overconfidence ➣ overcome througheducation, enhancement and emergence
training for and with citizens

Compound Disasters Leading toCatastrophic Disasters◆ Unexpected (disasters) – Souteigai “想定外”➣ Disaster beyond what one would expect◆ Unprecedented (disasters) – Mizou “未曽有”➣ The most disastrous event that has ever beenrecordedWe, researchers, should not allow mass-media
to use these expressions too frequently.

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2024.3

Challenges for Increasing GeotechnicalEngineering’s Rolein IPCC（地盤工学のIPCC への貢献の挑戦）

Some Activities of Geotechnics for Climate Change
Year

Country

Reference

2002

2012

Research as CoE on Climate Change-induced Geo-disasters

NorwayCarried out at Norwegian Geotechnical Institute (NGI). The representative is
Dr. Farokh Nadhim.

2005

2009

Strategic project on climate change adaptation called S-4

Japan

Supported by Ministry of Environment

2010

2014

Strategic project on climate change adaptation called S-8

Japan

Supported by Ministry of Environment

2013

Present

Asian Technical Committee (ATC1) on Geotechnical Mitigation
and Adaptation to Climate Change-Induced Geo-disasters in
Asia-Pacific Regions

Asia

Activity of ATC1 is included in International Society of Soil Mechanics &Foundation Engineering

2013

2014

Research Committee on Synergy of Geo-disaster Risk
management and Climate Change Adaptation

Japan

Organized by Japan Geotechnical Society (JGS) and chaired by Professor
Hemanta Hazarika (Kyushu University)

2014

2015

Course on Global Warming-induced Geo-environments andGeo-disasters

Japan

Journal of Japan Geotechnical Engineering (in Japanese)

2016

2016

56th Rankine Lecture entiled Geotechnics,Energy and Climate
Change

UK

2016

2016

Symposium on Climate Change-induced Geo-disaster Risk in
Snowy Regions

Japan

Organized by Hokkaido Branch of JGS which was chaired by Professor
Tatsuya Ishikawa of Hokkaido University

2017

2017

2017 PGS Workshop &15th G. A. Leonards Lecture on Climate
Change & Geotechnical Engineering

USA

Held at Purdue University

2018

2018

Special Issue on Climate Change & Geotechnical Engineering

Thailand

Journal of Southeast Asian Geotechnical Society (SEAGS) & Association of
Geotechncal Societies in South East Asia (AGSSEA), Vol. 47, No. 1

2019Present

Colloborative Geotechnical Research Group in Branches of
Hokkaido & Kyushu

Japan

Under the support from Geotechnical Research Committee in JapaneseSociety of Civil Engineers (JSCE)2020

1st International Conference on CONSTRUCTION RESOURCESFOR ENVIRONMENTALLY SUSTAINABLE TECHNOLOGIES(CREST 2020)

Japan

Climate change is a topic.

2023

9th International Conf. on Environmental Geotechnics

GreeceClimate change is raised up as a topic for the first time.

2023

CREST 2023

Japan

Climate change is a topic.

From

Activity

To

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Delivered by Professor Richard Jardine (Imperial College) under Organisation
by British Geotechnical Association－

2024.3

56th Rankine Lecture given by Prof. R. Jardine, Imperial College,
UK, entitled “Geotechnics, energy and climate change” 2016
◆ Part 1 specifically examines support of offshorehydrocarbon production.
◆ Part 2 describes investigations into the geotechnicalimpact of climate change in a permafrost region and apeatland study that contributes to alleviating flood risks
exacerbated by climate change.
◆ Part 3 outlines research that is improving the economics of renewable
offshore wind energy for multi-pile and monopile supported turbines.

There can be no doubt that his lecture raises a profound challenge!

Constitution of IPCC:
Three Working Groups◆ WGI: provides scientific information related to
the global community to meet challenges posed byclimate change.
◆ WGII: assesses impacts of climate change froma world-wide to a regional view of ecosystems andbiodiversity, and of humans and their diverse
societies, cultures and settlements.
◆ WGIII: specifically examines climate change
mitigation, assessing methods for reducing andremoving greenhouse gas emissions(AR5 WG II Part A, 2014)

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2024.3

Managing the Risks of Extreme Events and Disasters to
Advance Climate Change Adaptation (SREX Report)◆ A Special Report of Working Groups I and II of theIntergovernmental Panel on Climate Change (IPCC)
published in 2012
◆ Field, C.B., V. Barros, T.F. Stocker, D. Qin, D.J.
Dokken, K.L. Ebi, M.D. Mastrandrea, K.J. Mach, G.-K.
Plattner, S.K. Allen, M. Tignor, and P.M. Midgley (eds.).
◆ Cambridge University Press, Cambridge, UK, andNew York, NY, USA, 582 pp.

No references to geotechnical aspects
were included!

IPCC and Geotechnical Engineering（IPCC AR には地盤工学的記述はない!）◆ From geotechnical perspective• Geotechnical findings scarcely reflected in any assessment report• No keywords such as landslide or land subsidence have been observed in the glossary andindex.
◆ Why? Through experiences as review editors of AR5 (2011--2014)
・ No authors from geotechnical fields
・ No recognition of geotechnical engineering in academia
・ No recognition of geo-disasters or geo-hazards
・ Low recognition of climate change importance in Geotechnical Society◆ How should we do this?（どうすべきか?何もしなくてよいか?）・ Efforts from ICSMGE are needed・ Strategic submission to journals associated with high IF
・ Not only from academic-oriented studies but also from policy-oriented studies

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2024.3

Summary and Conclusions（まとめ）This study was conducted to present knowledge and lessons learned from several case studies indifferent countries in Asia, particularly in Japan. Based on this knowledge and lessons, special
emphases have been placed on the importance of ameliorating compound geo-disasters, which include
events combined with and without climate change-associated or non-associated factors. For
preparation and countermeasures to be pursued in the future, we must acknowledge the following
techniques and policies.

i) Greater insight should be sought in relation to proactive rather thanreactive measures that underscore the concept of “adaptive adaptation”.
ii) Such emission resources as used tires and other industrial byproducts
should be used to develop adaptive measures. At the same time, locallyavailable materials are the same.
iii) Green infrastructure should be explored to combine with grey
infrastructures and brown earth structures.
iv) Geotechnical engineering should/can contribute to internationalorganizations studying climate change, such as the IPCC.

Thank you for your kind attention!

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2024.3

2. 「丸太を用いた液状化対策による気候変動緩和貢献の事例紹介」

村田拓海

Contribution to Climate Change Mitigation ofUsing Logs for Liquefaction Countermeasures: a Case Study（丸太を用いた液状化対策による気候変動緩和貢献の事例紹介）

November 20, 2023
Takumi Murata (Tobishima Corporation)

CREST2023

Workshop2“Practices for Sustainable and Resilient Geotechnology”

Contents
 Contribution to Climate Change Mitigation by using Wood
(木材利用による気候変動緩和への貢献)
 Overview of LP-LiC Method(丸太を用いた液状化対策の概要)
 A Case Study of Application to a Large Residential Area
(大規模分譲住宅地への適用事例)
 Carbon Storage Effect of LP-LiC method(丸太を用いた液状化対策による炭素貯効果)
 Summary(まとめ)

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Contribution to Climate Change Mitigation by using Wood
Effect of mature forest on CO2 reduction
Question
How much does this mature jungle
contribute to CO2 reduction from theatmosphere?
(成熟した森林はどれくらい大気中のCO2削減に貢献している?)

AnswerMature forest does not contribute to
CO2 reduction in the atmosphere(成熟した森林は大気中のCO2削減に貢献していない)

Rondonia，Brazil
フレッド・ピアス:写真が語る地球激変，ゆまに書房

CREST2023

Workshop2“Practices for Sustainable and Resilient Geotechnology”

Contribution to Climate Change Mitigation by using Wood
Effect of mature forest on CO2 reduction
Young phase

Maturity phase

Old age phase(若齢段階)(成熟段階)(老齢段階)

Mature forests will not
contribute to CO2 reduction
from the atmosphere

Amount of carbon

Amount of carbon absorption
from the atmosphere byphotosynthesis
Amount of carbon emission
due to breathing and decay offallen branches and leaves

Amount of carbon stockAge of tree
林野庁:平成25年度森林及び林業の動向・平成26年度森林及び林業施策

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2024.3

Contribution to Climate Change Mitigation by using Wood
Carbon storage and wood use

Amount of carbon stock

Harvesting
Scrap
wood

Materials

ForestTo increase the total amount ofCO2carbon stock, increasing theamount of trees and wood

Decay
etc

Scrap
wood

CO2

CO2

Decay
etc

Burning

0

50

Time

(炭素ストックの総量を増やすには，樹木や木材製品の量を増やすことが重要)

Fuel

Recycling

products is important.

 Extend the service life span
(⾧期間の利用) Increase the use of wood

100 years

products

Wood products continue to fix
carbon as wood after harvest
CREST2023(大量に利用)Workshop2“Practices for Sustainable and Resilient Geotechnology”

Contribution to Climate Change Mitigation by using Wood
Measures to reduce CO2 from the atmosphere by increasing the amount of wood

Plant trees and increase the amount of trees(植林し樹木の数を増やす)

Encourage the growth of trees by thinningand increase the volume of wood
(間伐し樹木の生⾧を促し材積を増やす)

Use wood products in urban area
and increase the total amount of wood
(木材を利用し都市部で木材の総量を増やす)
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2024.3

Contribution to Climate Change Mitigation by using Wood
Durability of wood in the ground

Dekijima coast

AjigasawaAge

28,000 years ago

Treespecies

Coniferous trees(Ezo Spruce and Larch etc)

Soil type Peat

Aomori

Hirosaki

Dekijima coast buried forest
It became submerged due toenvironmental changes such as flooding.

CREST2023

Workshop2“Practices for Sustainable and Resilient Geotechnology”

Contribution to Climate Change Mitigation by using Wood
Durability of wood in the ground
Building Completion

Inclination of Building

1959

Number of floors

4

Building structure

RC

Building foundation

Pile

Pile type

Wood

Wood placed in the groundis high durability undercertain conditions(ある条件下において，地中の木材は高い耐久性を持つ)

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2024.3

Contribution to Climate Change Mitigation by using Wood
Durability of wood in the ground
Z: No
measures

A: Resin

B: Clay

C: Dense
sand

D: Loosesand

8cm diameter log Resin

1cm thick

6cm thick

6cm thick

Soil

Unit：cm13

Ground water level

Log

70
30

120
100

View of large-scale container

100 cm in height,
8 cm in diameter

50
7
Going in and out of water

Tree species:
Cedar and Larch

Drain layer

Schematic cross section of log arrangement in the large-scale container
CREST2023

Workshop2“Practices for Sustainable and Resilient Geotechnology”

Contribution to Climate Change Mitigation by using Wood

Rc Japanese cedar
1173days - 1187days

Rc：Normalized compressive strength ：Compressive strength at any portion
water level (Completely sound)

Assumption
 The strength below the lowest
water level, L, keeps theinitial strength forever.
 Scattering within one log isvery small.

 Wood biodeterioration covered with clay does not occur at

Ce. no mea. lo. natur.

Ce. no mea. den. natur.

Types of covering(無対策)

Ce. no mea. backfill.

(緩い砂)

Ce. Lo. sand

(密な砂)

Ce. den. sandLowestwater(粘土)

Highestwater 100(%)
LL：Compressive strength below the lowest

Above the highest W.L.
Within the variation of W.L.
Below the lowest W.L.
Ce. Clay

Soil

Medium-sccal con. ■Normalized compressive strength of logs after 3 years

Large-sccal con.

120
110
100
90
80
70
60
50
40
30
20
10
0
Ce. resin

Normalized strength σ/σL (%)

Durability of wood in the groundall even if the wood is higher than the groundwater level.
(粘土に覆われていれば，地下水位以浅でも生物劣化は生じない)

 Wood biodeterioration hardly occurs within the changing
range of water level.
(水位変動域では，生物劣化がほとんど生じない)

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2024.3

Contribution to Climate Change Mitigation by using Wood
Characteristics of soft ground
CommonfeatureGroundtype

Time ofdamageOccurrence
phenomenon

Damage type

Settlement
 Shallow

Clay

Consolidation

Ordinary

Slip failure

groundwater

LP-SoC

Inclination

MethodHorizontal displacement, etc.

level
 New deposition

Settlement

 Very soft
 No gravel

Differential settlement

Differential settlement
Sand

Earthquake

Liquefaction

Inclination
UpliftLP-LiC
MethodHorizontal displacement, etc.
CREST2023

Workshop2“Practices for Sustainable and Resilient Geotechnology”

Contribution to Climate Change Mitigation by using Wood
Summary Trees absorb carbon dioxide from the atmosphere, fix carbon, and produce oxygen, so
the growth of trees that stock carbon will reduce the carbon dioxide in the atmosphere.
Using more products made of wood, which also contain carbon, will reduce carbon
dioxide the same as the growth of trees.
(樹木は，大気中の二酸化炭素を吸収し，炭素を固定するため，樹木が成⾧すれば大気中の二酸化炭素を減らすことができる．同じく炭素を含む木材製品を多く使うこととで，樹木の成⾧と同じように二酸化炭素を減らすことができる．)

 Wood has high durability in groundwater, and biodeterioration of wood scarcely occurs
within the changing range of water levels. Wood biodeterioration covered with clay does
not occur at all even if the wood is higher than the groundwater level.
(木材は地下水位以深で高い耐久性を示し，地下水位変動域でも生物劣化はほとんど生じない．地下水位以浅であっても，粘土で覆われていれば生物劣化は生じない．)

 Soft ground has always high groundwater level. So, the log in the soft ground can stock
carbon almost forever.
(軟弱地盤は地下水位が高い．このため，軟弱地盤中の丸太は炭素を半永久的に貯蔵することができる．)

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2024.3

Overview of LP-LiC Method
Liquefaction phenomenon
Typical damage due to liquefaction

Conditions for occurrenceof liquefaction

Bridge fall

The 1964 Niigata earthquake SandInclination of building(砂)Rail meandering Loose
Dense
(密実)
(緩い)

 Saturated withwater
(地下水で飽和)

Inclination of apartment

 External force(外力)

Ejected sand
地盤工学会:液状化災害発生直後の新潟市街地航空写真集，1999.2.

新潟日報社:新潟地震から40年～大災害を振り返る～）

CREST2023

Workshop2“Practices for Sustainable and Resilient Geotechnology”

Overview of LP-LiC Method
What is LP-LiC method ?

Log Piling Method for Liquefaction Mitigation and Carbon Stock Piling logs improves theground by densifying theloose sand
(丸太を地盤に打設することで，緩い砂地盤を密な砂地盤に改良する)

 Logs below the groundwaterlevel can stock carbon in the
ground(地下水位以深の丸太は，地中に炭素を貯蔵できる)
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2024.3

Overview of LP-LiC Method
Effect of liquefaction countermeasures by LP-LiC method
Log

3.6m

2.3m
1.8m

5波

100

20波

5波

A(gal)

加速度 A(gal)

150

50
0
-50
-100

大型模型振動実験(X 軸方向)

4Hz

-150
0.0

5.0

10.0
時間

15.0

t(s)

Large-scale shaking table test
CREST2023

Workshop2“Practices for Sustainable and Resilient Geotechnology”

Overview of LP-LiC Method
Effect of liquefaction countermeasures by LP-LiC method

Input motion:150 Gal (157 Gal)
Improvement method:Unimprovement (無対策地盤)
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2024.3

Overview of LP-LiC Method
Effect of liquefaction countermeasures by LP-LiC method

Input motion:150 Gal (165 Gal)
Improvement method:Log pilling, Pitch = 4D(丸太打設地盤)
CREST2023

Workshop2“Practices for Sustainable and Resilient Geotechnology”

Overview of LP-LiC Method
Effect of liquefaction countermeasures by LP-LiC method
Large

Earthquake force

Small

Degree of damage

Small

Large

Cumulative settlement ΣS (mm)Input acceleration A(Gal)
0

100

200

300

400

500

0

100

200

NIP
P5D
P4D
DNS

Large-scale shaking table test
Kasumigaura sand
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2024.3

A Case Study of Application to a Large Residential Area
Construction site

Tokyo
Tokyo Bay
Yokohama
Pacific Ocean

CREST2023

Workshop2“Practices for Sustainable and Resilient Geotechnology”

A Case Study of Application to a Large Residential Area
Overview of construction
ca. 150 m

A=13,382 m2
n=13,420 logs
B=1.0m

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－

Log

4.0 m

Tree species：
Japanese cedar
andJapanese larchca. 100 m

Crushed stone
Covering soil

1.2 m

Ground surface

Diameter at the bottom tipof log : 0.15 m“Practices for Sustainable and Resilient Geotechnology”

2024.3

A Case Study of Application to a Large Residential Area
Construction process using LP-LiC method

CREST2023

Workshop2“Practices for Sustainable and Resilient Geotechnology”

A Case Study of Application to a Large Residential Area
Results of liquefaction countermeasures
N-value
0

10

20

Safety factor against liquefaction

30

0.0

0.0

Minimum safety factor FL against

1.0

Fc

4.0
5.0

As

6.0
7.0
8.0
9.0

Boring no.

3.0

1.0

shallower than 5 m

No.3

Minimum safety factor FL againstliquefaction(from GL 0.0 m to GL -5.0 m)
Original ground

Designed

1

2.46

2.46

2

0.96

1.17

3

0.97

1.18

4

2.40

2.43

5

1.16

1.44

Depth Z (m)Depth Z (m)

3.0

2.0

Recommendations for design ofbuilding foundations in Japanground liquefaction for each boring site

2.0

1.0

0.0

2.0

Log

3.0

4.0

5.0

Original ground
Designed value

No.3 (Original)

After log piling

10.0

6.0

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2024.3

Carbon Storage Effect of LP-LiC method

790,627

800,000

752,959

This construction method can

700,000
600,000
500,000

CO2 stockcontribute to reducing

CO2 balance

greenhouse gases, as long as

400,000

planting trees continues after

300,000

harvest.

200,000(伐採後も植林を続けることで，温室効果

0

Stock

100,000

Emission

Amount of CO 2 stock or emission（kg-CO2）

Application to a Large Residential Area
900,000

ガスの削減に貢献できる)-37,668-100,000

Stock in logs

Log pilingJointmaterial

Total

Category
CREST2023

Workshop2“Practices for Sustainable and Resilient Geotechnology”

Carbon Storage Effect of LP-LiC method
Relationship between carbon storage per volume of liquefaction improvement and pitch of logs

90
80
70
60
50
40
30
20

Storage

10
0

-1

100

Emission

Carbon storage pervolume of liquefaction improvement(kg-CO2/m3-imp)0

Carbon storage pervolume of liquefaction improvement(kg-CO2/m3-imp)

Carbon storage pervolume of liquefaction improvement(kg-CO2/m3-imp)

100

90

-2

80

-3

70

-4

60
50

-5
-6

40

-7

30
20

-8

0

-10
2.0 DT

3.0 DT

4.0 DT

5.0 DT

6.0 DT

7.0 DT

2.0 DT

3.0 DT

Pitch of log B

Carbon storage
by logs

4.0 DT

5.0 DT

6.0DT

2.0 DT

7.0 DT

Pitch of log B＋

Storage10-9by construction－

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4.0 DT

5.0 DT

6.0 DT

Pitch of log B

Carbon Emission

CREST2023

3.0 DT=

Carbon storage
by construction“Practices for Sustainable and Resilient Geotechnology”

7.0 DT2024.3

Conclusions
 Trees absorb carbon dioxide from the atmosphere, fix carbon, and produce oxygen, so
the growth of trees that stock carbon will reduce the carbon dioxide in the atmosphere.
Using more products made of wood, which also contain carbon, will reduce carbon
dioxide the same as the growth of trees.
(樹木は，大気中の二酸化炭素を吸収し，炭素を固定するため，樹木が成⾧すれば大気中の二酸化炭素を減らすことができる．同じく炭素を含む木材製品を多く使うこととで，樹木の成⾧と同じように二酸化炭素を減らすことができる．)

 Wood has high durability in groundwater. So, the log in the soft ground can stock carbon
almost forever.
(木材は地下水位以深で高い耐久性を示す．このため，軟弱地盤中の丸太は炭素を半永久的に貯蔵することができる．)

 The carbon stock effect of LP-LiC was found to exceed the amount of CO2 emitted as aresult of the construction work by more than a factor of 10, and therefore, contributed toa reduction in greenhouse.
(LP-LiC工法による炭素貯蔵効果は，施工によるCO2排出量の10倍以上となり，温室効果ガスの削減に大きく貢献する．)

CREST2023

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Thank You for Your Attention !
( ご清聴ありがとうございました ! )CREST2023－

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2024.3

3. 「産官学連携による地方都市における木材利用促進と社会貢献」

吉田雅穂

2nd International Conference on Construction Resources for Environmentally
Sustainable Technologies: CREST 2023
October 20th, 2023, Fukuoka International Congress Center

Promoting the utilization of wood in regional cities
and contributing to society through industry–
government–academia collaboration
産官学連携による地方都市における木材利用促進と社会貢献
Masaho YOSHIDA
President, Research Society of Wood Utilization in Fukui
Professor, National Institute of Technology, Fukui College
吉田雅穂
福井県木材利用研究会会⾧
福井工業高等専門学校教授

Research Society of Wood Utilization in Fukui
福井県木材利用研究会
Establishment 発足
April 2010 2010年4月
Purpose 目的
To promote the use and stable supply of wood in the fields of civil engineering,architectur and biomass, and to conduct surveys and research, dissemination andawareness-raising, and various activities to promote cooperation andcoordination among related parties.
「土木」，「建築」，「バイオマス」の各分野における，木材の利用拡大と安定供給を図ること目的に，調査・研究，普及・啓発，関係者の連携・協調を促進する
ための様々な活動を行う．
Subcommittees 分科会
Civil engineering, Architecture, Stable supply and biomass
土木系，建築系，バイオマス安定供給
Number of members 会員数
63 people / 29 (25 Companies), 16 (9 Public organizations), 15 (10 local
governments), 3 (2 Schools)
63人／企業29人（25社），公的団体16人（9機関），地方自治体15人（10機関），
学校3人（2機関）

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2024.3

OthersPlanted

その他

人工林

3%

39%

Fukui Prefecture
福井県

Area
森林面積

Natural
天然林
58%
Planted 人工林
Japanese cedar スギ 87％
Japanese cypress ヒノキ 5%

Item 区分Japan 日本

Fukui 福井県

Area Forest面積

37,800,000 ha

420,000 ha（31）

Forest 森林面積

25,080,000 ha

310,000 ha

Planted 人工林

10,200,0000
ha

120,000 ha

Natural 天然林
Others その他森林

14,880,000 ha

180.000 ha
10,000 ha

Use of Wood in Architecture
公共施設の内装木質化事例
建築における木材利用

JR Ashiharaonsen Station (Awara City)

Ichijodani Asakura Clan Site Museum (Fukui City)

JR芦原温泉駅（あわら市）

一乗谷朝倉氏遺跡博物館（福井市）

－

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2024.3

The reason for the establishment of the research society

研究会発足のきっかけ

Heavy rain fall in Fukui on July 18, 20042004年7月18日福井豪雨
人的被害
死者4人，行方不明者1人，負傷者9人
住家被害
全壊69棟，半壊140棟，一部破損229
棟
床下浸水8000棟以上
Asuwa River Breach
足羽川の決壊Bridge outflow
on the Etsumihokusen Line
越美北線の橋梁流出

Casualties
4 dead, 1 missing, 9 injured
Damage to houses
Totally destroyed 69, partiallydestroyed 140, partially damaged 229 ,More than 8,000 houses flooded
under the floor

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2024.3

Excavation survey of wooden piles at Saiwai Bridge
幸橋の木杭の掘り出し調査

Completion in 1933, 4th
generation, RC bridge
1933年竣工，4代目，RC橋
Length 杭⾧： 1.4m～5.7m
Diameter 直径： 17cm～20cm
Type 樹種： Pine マツ科マツ属
Year 埋設期間： 74年（1932～
2006）
Number 打設本数： 90本
Interval 打設間隔： 0.9～1.0m

Saiwai Bridge withstood the 1948 Fukui Earthquake (M7.1)
1948年福井地震（M7.1）に耐えた幸橋
Fukui Station
福井駅
Kida Bridge
木田橋

Saiwai Bridge
幸橋
Asuwa River
足羽川

Death: 3,769
Collapsed house：
More than 34,000
死者：3,769人
全壊：34,000棟以上[国土地理院］－

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2024.3

Full-scale field experiment at Tsuruga Port
敦賀港における実大現場実験
Fukui Prefectural Civil Engineering Department
Tobishima Corporation
National Colldge of Technology, Fukui Colledge
Kobe University
福井県土木部
飛島建設技術研究所
福井工業高等専門学校
神戸大学

Creation of artificial soft ground
人工軟弱地盤の作製

Fine fractionated sandy gravel (gravel: 41%, sand: 28%, fine sand: 31%)
細粒分質砂質礫（礫分：41%，砂分：28%，細粒分：31%）

－

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2024.3

Construction status on site
現場の施工状況

Logs peeled from the barkExperiment yard 実験ヤード

皮むき丸太

Driving of log 丸太打設

Embankment 盛土

Carbon storage of wood and carbon dioxide emissions from operations
丸太の炭素貯蔵量と作業による二酸化炭素排出量5.0
工事による二酸化炭素排出

2.0

1.0

工事 による
二酸化炭 素貯蔵 量

試験条件
丸太(スギ)ピッチ：0.5m
丸太運搬距離：68.3km
3
サンドマット(45.5m ):片道9km地点より運搬
3
盛土(100m ):片道2km地点より運搬
通勤考慮

貯蔵

Storage

作業項目

サン
ドマ
ット
盛土
(片
道2
km)
二酸
化炭
素収
支

丸太
打設

丸太
運搬

-1.0

丸太
加工

0.0
伐採
搬出

二酸化炭素貯蔵量（t-CO 2）

実測値
二酸化炭素収支

3.0

丸太
によ
る貯
蔵
地拵
え～
枝打
ち

Carbon dioxide storage

4.0

Work contents

－

60

－

Emissions
排出2024.3

Social changes in wood utilization
木材利用に関する社会の変化
平成9（1997）年 京都議定書 Kyoto Protocol
平成16（2004）年

福井豪雨 Fukui Heavy Rain Fall

平成19（2007）年

土木における木材の利用拡大に関する横断的研究会 発足

Cross-sectional Study Group on Expanding the Use of Wood in Civil Engineering is established.

平成21（2009）年
土木学会木材工学特別委員会 設置
Special Committee on Wood Engineering of the Civil Engineering Society Setting
平成22（2010）年「公共建築物等における木材の利用の促進に関する法律」
Act on Promotion of Utilization of Wood in Public Buildings, etc.
平成22（2010）年
福井県木材利用研究会 発足
Research Society of Wood Utilization in Fukui is established.
平成23（2011）年

東日本大震災 Great East Japan Earthquake

平成24（2012）年
土木学会木材工学委員会 発足
The Civil Engineering Society, Wood Engineering Committee is established.
平成25（2013）年「国土強靭化基本法」 Basic Act for National Resilience

令和3（2021）年 「脱炭素社会の実現に資する等のための建築物等における木材の利用の促進に関する法律」

Act on Promotion of Utilization of Wood in Buildings, etc. to Contribute to Realization of a Decarbonized Society, etc.

Activities of Research Society of Wood
Utilization in Fukui
福井県木材利用研究会の活動

－

61

－

2024.3

Wood Utilization Symposium in Fukui
木材利用シンポジウムin福井

December 6, 2020
Fukui International
Activities Plaza
164 participants
2020年11月6日
福井県国際交流会館
参加者164名
December 11, 2010
Fukui International Activities
Plaza
200 participants
2010年12月11日
福井県国際交流会館
参加者200名

Regular study meeting
定例研究会

2023/6/26, Fukui Forest Association
2023/6/26，福井県森林組合連合会

－

62

－

2024.3

Field trip 見学会

Biomass Power Plant(Fukui Green Power, Ono City)
バイオマス発電所（福井グリーンパワー，大野市）

Wood Market(Fukui Prefecture Wood Market
Cooperative Association, Fukui City)
木材市場（福井県木材市売協同組合，福井市）

Field trip 見学会
Flood control dam(Miyama-cho, Fukui City)
治山ダム（福井市美山町）

Sound Insulation Wall
(Geba, Fukui City)
遮音壁（福井市下馬）－63－

2024.3

Field trip 見学会

Fish Reef(Iimori, Obama City)
魚礁（小浜市飯盛）Fishway(Kyozen, Eiheiji-cho)
魚道（永平寺町京善）

Wood use seminar for children and their parents
親子で学ぶ木材利用セミナー

15 pairs of parents and children from inside and outside of the prefecture, 40 people intotal
県内外より15組計40名の親子

－

64

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2024.3

Wood utilization exhibition in Fukui City
福井市木材利用展示会（2023年10月2～6日）

Panels introducing Research Society of Wood Utilization in Fukui and products of member companies
福井県木材利用研究会の紹介パネルと会員企業の製品

Received the JSCE Kansai Branch Regional Activity Award for 2021
2021年度土木学会関西支部 地域活動賞 受賞

April 14, 2022, Construction Exchange Meeting (Osaka City, Osaka Prefecture)
2022年4月14日，建設交流館（大阪府大阪市）

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65

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2024.3

Example of wood utilization for soft
ground improvement in Fukui Prefecture

福井県における
軟弱地盤対策での木材利用事例

Soft ground improvement for detached house (2013/3/6, Sakai City)
戸建住宅の軟弱地盤対策（2013/3/6，坂井市）
Diameter 末口径： 14 cm
Length ⾧ さ： 6 m
Interval 間隔：1～1.5 m
Number 本数：44 本

－

66

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2024.3

Liquefaction countermeasures for farm building (2016/2/29, Fukui City )農舎の液状化対策（2016/2/29，福井市 ）Diameter 末口径： 15 cm
Length ⾧ さ： 4 m
Interval 間隔：0.9 m
Number 本数：564 本

Liquefaction Countermeasures for Red Brick Warehouse (2014/8/9, Tsuruga City)
赤レンガ倉庫の液状化対策（2014/8/9，敦賀市）

Diameter 末口径： 15 cm
Length ⾧ さ： 3 m
Number 本数：700 本以上

－

67

－

2024.3

Soft ground improvement for road body (2011/7/8, Obama City)
道路路体の軟弱地盤対策（2011/7/8，小浜市）
Diameter 末口径： 12 cm
Length ⾧ さ： 4 m

Soft ground improvement for embankment (2012/4/13, Mikata PA on Wakasa-Maizuru Expressway)
盛土の軟弱地盤対策（2012/4/13，若狭舞鶴自動車道三方PA）

Diameter 末口径： 14 cm
Length ⾧ さ： 4 m
Number 本数：723 本

－

68

－

2024.3

Soft ground improvement for box culverts (2016/2/4, Sabae City)
ボックスカルバートの軟弱地盤対策（2016/2/4，鯖江市）

Diameter 末口径： 18 cm
Length ⾧ さ： 4 m
Interval 間隔：0.75～1.00 m

Soft ground improvement for levees (2020/11/16, Obama City)
堤防の軟弱地盤対策（2020/11/16，小浜市）
Diameter 末口径： 18 cm
Length ⾧ さ： 4 m x 3本
Number 本数：約7.000 本

－

69

－

2024.3

Design and construction manual for soft ground improvement using log pile method
丸太杭工法を用いた軟弱地盤対策の設計・施工マニュアル

Excel版設計シート
Precast L-shaped retaining wall design sheet
Design sheet for precast box culvert
プレキャストL型擁壁の設計シート（土木編，建築編）
プレキャストボックスカルバートの設計シート（土木編）

Seminar for design andconstruction manual for soft
ground improvement using log
pile method
丸太杭工法を用いた軟弱地盤対策の設計・施工マニュアル講習会

March 2013 Published
Culvert (3m x 3m),vL-shaped
retaining wall (2m), Roadway
body
2013年3月刊行
カルバート（3m×3m），Ｌ型擁壁（2m），道路路体

Research and development of wood
utilization technology through industrygovernment-academia collaboration in Fukui
Prefecture
福井県の産官学連携による木材利用技術の研究開発
Industry: Miyama Town Forestry Cooperative
Government: Fukui Prefectural Department of Agriculture, Forestry
and Fisheries
Academia: Fukui National College of Technology
産：美山町森林組合
官：福井県農林水産部
学：福井工業高等専門学校

－

70

－

2024.3

Mechanical properties of saturated wood
飽水木材の力学特性の解明

Mechanical properties of saturated wood
飽水木材の力学特性の解明

－

71

－

2024.3

Sales of wood made in Fukui Prefecture to
Chiayi County, Taiwan
福井県産木材の台湾嘉義県へのセールス
Industry: Marvel Corporation
Government: Fukui Prefectural Department of Agriculture, Forestry
and Fisheries
Academia: Fukui National College of Technology
産：マーベルコーポレーション
官：福井県農林水産部
学：福井工業高等専門学校

Grant for Japan-Taiwan Industrial Cooperation Project
日台産業協力架け橋プロジェクト助成事業
October 12, 2023
Chiayi County Human
Resource Development
Office, Taiwan
2023年10月12日
台湾嘉義県人力発展所

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72

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2024.3

Conclusions まとめ“Promoting the utilization of wood in regional cities and contributing to society
through industry–government–academia collaboration”
Industrial Promotion and Regional Revitalization⇒Revitalization of the forestry and lumber industries by promoting the use oflumber in construction projects
National Land Stewardship and Climate Change Mitigation⇒Carbon stock through measures against soft ground using timber「産官学連携による地方都市における木材利用促進と社会貢献」◎産業振興と地域活性化⇒建設事業での木材利用促進による林業と製材業の活性化◎国土強靱化と気候変動緩和⇒木材を用いた軟弱地盤対策によるカーボンストック

－

73

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4. 「気候変動における持続可能性に関するLRRIの活動」安原一哉

LRRI Activities
for Climate Sustainability（気候サステナビリティに関するエルリの活動）
Workshop in CREST 2023 on“Practices for Sustainable and Resilient Geotechnology”• Kazuya YASUHARA, Ph.D.
• Representative of Local Resilience Research Institute (LRRI)(Professor Emeritus of Ibaraki University, Japan)-- November 20, 2023 -(see https://www.ic-crest.com/)(https://lrri.or.jp/)

Presentation Contents♦ What is LRRI?（LRRI って何？）♦ Activities of LRRI（活動内容）♦ How Should We at LRRI Cope with Climatic
Hazards?（LRRI は気候ハザードのどう立ち向かうか？）♦ LRRI Technologies for Climate Change
Responses（気候変動対応のためのLRRI関連技術）♦ Future Outlooks for Climate Change and SDGs at
LRRI （気候変動とSDGs対応の将来展望）

－

74

－

Outline of Local Resilient Research Institute(Non-profitable Private Sector : LRRI)♦ Mission Statement♦ Characteristic Features of the Organization• Engineering groups with rich humanity anddifferent experiences synergistically organized bysenior and middle leadersFirst Right Second Interest♦ Corporate Philosophy
Contribution to local resilience increase through knowledge
and wisdom of members and support for developing humanresources capable of finding and proposing solutions for
emerging difficulties, including climate change and SDG
related issues.
♦ Corporate Members
Organization
Japanese㈱JSP
アキレス㈱イーテック㈱エターナルプレザーブ㈱岡三リビック㈱（一社）GLOSS 研究会
昭和コンクリート工業㈱㈱T＆S開発設計事務所㈱高萩エンジニアリング
地水開発㈱東京インキ㈱福山コンサルタント㈱PEDI Civil Solutions ㈱水戸グリーンサービス㈱みらい建設工業㈱メトリー技術研究所㈱
木材活用地盤対策研究会• Providing opportunities and platforms on which
members and non-members collaborate to findsolutions for increasing local resilience• Providing platforms and lectures by which
members and non-members learn fundamental
and advanced knowledge about issues including
climate change

URL (Home page address)

EnglishJSP CO.,LTD.
ACHILLES CORPORATION

https://www.co-jsp.co.jp/
https://www.achilles.jp/
http://www.earth-techno.co.jp/
http://www.etp21.co.jp/
https://www.okasanlivic.co.jp/

Eternal Preserve Co., Ltd.
OKASANLIVIC.CO.,LTD.
Global Society for Smart Geo-Sustainnovation
Showa Concrete Co.,Ltd.
T&S Development Design Co., Ltd

https://www.geogloss21.org/
https://www.showa-con.co.jp/
https://www.tands-kaihatsu.co.jp/

http://www.t-hagi.co.jp/
https://chisui-kaihatsu.co.jp/
https://www.tokyoink.co.jp/
https://www.fukuyamaconsul.co.jp/
https://pedicivil.com/
http://www.greenservice.jp/
https://www.mirai-const.co.jp/
http://www.metry.jp/
https://mokuchiken.com/

TOKYO PRINTING INK MFG CO.,LTD.
FUKUYAMA CONSULTANTS CO., LTD.
PEDI Civil Solutions
Mito Green Service Corporation.
MIRAI CONSTRUCTION CO.,LTD.
metry Co., Ltd.

Divisions of LRRI
for SDGs and Climate Change[Consultant Division]（困難な課題解決応談）

Proposal of solutions forincreased local resilience

LRRI[Technical Development Division]（融合＆連携による新しい技術提案）[Educational Support Division]（継続教育，リスキリング支援）

Proposal of new technologies andpolicies for increasing local resilience・Support for human resource development
through seminar and training programs
・Publication of advanced technology related
to local resilience improvement

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75

－

Background and Roles of LRRI
[Seeds][Needs through Background]● Existence of potential senior
engineers capable ofsupporting them to findsolutions to extreme eventsand to increase local resilience
together with junior and middle
engineers● Necessity for new policies andtechnologies for responses toextreme events● Upgrading engineer andpolicymaker skills for finding suitable
solutions

Roles of LRRI

(1) Proposals of solutions for increasing local resilience, (2) Proposals of new technologies and policies
for increasing local resilience, (3) Support for human resource development through seminars andtraining programs, and (4) Book publication[Profiles of Corporate Officers]

Resilience Enhancement Leading to
Achievement of SGGs:What is Resilience?
Correlation with Other Keywords
Mitigation

ClimatehazardProgress of global warming

Vulnerability

External
force

Large gap
Adaptation
Agedinfrastructure

Developed
infrastructure
Defensive force
Past(was predictable)

Present

Future(unpredictable)from Komatsu et al. (2014)－

Resistance

Elapsedtime

Resilience shrinks vulnerability

76－

Climate Change Responses
and Their Synergies
Mitigation
GHG• Capture• Storage• Effective
utilization

Adaptation

Synergies of
Mitigation
and Adaptation

Disasters• Protection• Accommodation• Evacuation/ Relocation

Carbon neutral
Local Resilience
increase

Challenging issues

Dual Approach of Adaptation:
Top-down and Bottom-up Approaches
Scientific knowledge
Science-based,
Natural Science
Oriented

Public assistance（公助）

Mutual assistance（共助／協助）Community-based
Human Science
Oriented
Self assistance（自助）

Local residents’knowledge

－

77

－

8

Roles of Stakeholders

Residents

Researchers & Engineers

Roles of Private Sector (PS) in SDGs Including Climate
Change Responses【民間企業の役割／責任】♦ Demonstrate how private sector entities are prepared
to respond to SDGs including climate change.
♦ Demonstrate how their own techniques and skills
enable contributions to SDGs
♦ Disclose issues related to climate change associatedrisks and opportunities in accordance with proposals by
the Task Force on Climate-related Financial Disclosures(TCFD)(2017) (https://adaptation
platform.nies.go.jp/private_sector/tcfd/index.html)

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78

－

LRRI Technologies for
Infrastructural Sustainability[Part 1] Techniques for Infrastructural
Sustainability（インフラ長寿命化技術）

Tools for Reducing Effects of Extreme
EventsSoftwareHardware•Strengthening resilience ofinfrastructure• Hazard prediction•

Development of IoT, ICT, and DX• Easily usable hazard maps•

Monitoring tools• Evacuation support systems•

Temporary and permanent
recovery techniques

NPOs,
NGOs, etc.

Command-ware

Human-ware•Community-based adaptation•

Self help and mutual help•

Educational support andenlightenment for awarenessbuilding－

79•

Public help•

Transmission of information forsafe and effective evacuation•

Enlightenment for awarenessbuilding for local residents•

NPOs, NGOs, etc.

－

12Techniques for Increasing Resilience against
Infrastructural Aging and Earthquakes（橋梁の長寿命化）(1) Smoothly(Foam Support Technic)
workable

Foam Support Method〇供用しながら施工可〇騒音が少ない〇ヤードが小さい(2) Environmentallyfriendly〇軟弱地盤に適用〇埋設管の負荷軽減〇住宅密集地に採用可(3) Economical〇高さによるが撤去・架け換えより安価

Filling EPS and urethane into spaces between bridge piers(Developed by JSP Co. Ltd. in cooperation with Achilles Corporation,
Okasanlivic Co. Ltd., and Showa Concrete Industry Co. Ltd.)

Effects of Foamed Geosynthetics (Geofoam)
against Ageing of Bridges[Testing condition][Test results](1) Combining EPS with urethane is effective for
reducing earthquake damage.
(2) FCB and flowable concrete are also available as atechnique for increasing anti-earthquake capabilities.

(□) Input acceleration: 200 cm/s2(□) Frequency: 4 Hz(□) No. of cycles: 30 (sinusoidal)(a) Before test(a) Before test(b) After test(b) After test(a) Without RF

Outline of laboratory model tests(simulating Level 1 earthquake)(b) With RF（EPS with urethane）

Example of shaking table tests using
Foam Support Method (FSM)

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Infrastructural Rehabilitation Using Geofoam

Tunnel backfill void repaired using urethane injection“Tn-p Method”
Least destructive and environmentally safest tunnel repair
method (Achilles Corp.)

BEFORE♦ Features• Only compact foam injection
equipment is required.
• Urethane foam is light but also
durable and supportive.
• Backfill foam can be cured in a wet
environment, even with standing water.

AFTER

Construction site

Item

Unit

SK-01

SK-02

SK-03

SK-04

SK-05

SK-06

Foam
density

kg/m3

40±4

30±3

100±2060±9150±30175±30Compressive
strength

N/mm2

≥0.2

≥0.14

≥0.9

≥0.45

≥1.0

≥1.5

Quantitative Risk Analysis (QRA) for Major-Risk Plants(After H.N. Phan, et al., J. of Loss Prevention in the Process Industries, Vol. 53, May 2018, pp. 136-148)
Industrial plants

A Novel Framework for QRA under NATECH events

Earthquakes

NATECH events (Natural Hazard Triggering Technological Disasters )Propagation
effectUndamaged
unit
Secondaryundamaged
unit

Probit function for the damage
caused by physical effects

Unit damaged byearthquake
eventsSystem level

Component level(Structural world)

Damage Domino Conseq. Loss
Damage Seismic
Scenario Effects Analysis Analysis Analysis Demand

NaturalHazardP( X|Y) is the conditional probability of X given Y.

PEDI Civil Solutions (https://pedicivil.com/ )Contact Person: nam.phan@pedicivil.com (Mr.Nam Phan)－

Damage chains andpropagate damage
are automaticallygenerated based onMonte Carlo
Simulations

Machine learning-based Parametric Fragility Curves

Annual probability of risk due to loss of volume(Industrial/Chemical world)

Multiple accidental
chains are adopted
considering the
propagation effects
due the loss ofcontainment (LOC)81－

LRRI Technologies for
Infrastructural Sustainability[Part 2] Climate Sustainability

Technologies for Climate Sustainability（気候持続性技術）♦ Mitigation Techniques（緩和技術）♦ Adaptation Techniques（適応技術）: Hard, Softand Human Measures
In addition,（加えて）♦ Synergetic Techniques（融合技術）♦ Multiple Purpose Techniques（多目的技術）
Aim at proposal of unprecedented techniqueswith newly added value

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－

Log Piling Method for Soft Ground and Carbon Stock（丸太打設軟弱地盤対策＆カーボンストック工法）●日本建築センター (BCJ評定-FD0577-02)

Bearing capacity oflogs and ground＋

Carbon stock in logs

Load
Bearing capacity of ground

Surface ground
Foundation
slab

Cover soil

Bearing capacity of logs

GravelFrictionLog

End bearing capacity

Soft soil layer

Log Piling Method for Soft Ground and Carbon Stock（丸太打設軟弱地盤対策＆カーボンストック工法）

Logs are useful for both carbon storage and for reduction of liquefaction damage.

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83

－

Comparison of GHG Emissions among
Liquefaction Countermeasures
SECURE-G: Through geosynthetics reinforcement and gravel stiffness,embankment deformation is restrained by reducing lateral movement
TOFT(Deep Mixing Method)

SCP

SECURE-G

S
C e
r c
o t
s i
s o
n

1,283t-CO2eq/100m(10.8)

422 t-CO 2eq/100m(3.5)
119 t-CO2eq/100m(1.0)

GHG emissions from geosynthetics reinforcement are retrieved from EPD(From Eternal Preserve Co. Ltd., エターナルプレザーブ㈱）Sandbag (Geo-tube) for Beach Cliff Erosion
Countermeasures against SLR and intensified Typhoon waves
Sandbags reduce beach cliff and sand dune degradation
caused by coastal erosion together with reinforcement ofa dyke. Moreover, they can mitigate salt damage andflying sand at coastal areas.
In contrast to concrete walls, construction work is swift.
The sandbags also maintain the landscape because they
are embedded in the dyke.
Sand dune before
placement of sandbags
Sandbags
Sand dune
22（(From Mitsui Chemicals Industrial Products Ltd..（三井化学産資㈱）

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84

－

Slope Surface Protection against Torrential Rainsand Global WarmingThis earth reinforcement technology is characterized by the combination of
geocells (called “Groundcells”) with vegetation against surface erosionand erosion caused by torrential rainfall. This technique is also available
for heat protection through EPS.
(RTR ® Method owned by Tokyo Printing Ink Mfg. Co. Ltd.（東京インキ㈱）Rainwater Storage Tank
（多目的技術）

Geopool AE-1 is a rainwater infiltration and storage tankused as a countermeasure against floods during torrential
rains . Because it is molded with eco - friendly recycledplastic, it is lightweight and easy to handle. It can reduce
costs and can shorten construction periods compared toconventional concrete tanks.

Flood measures and rainwater storage► multi-purpose and multi-function(a) Infiltration type

Basic piece(reversed)(b) Storage type

Wall piece
Basic piece(Geopool AE-1; Okasanlivic Co., Ltd.)

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85

－

Technique for River Basin Disaster Resilienceand Sustainability by All (Flood Disaster Countermeasures:
Emergency Roadway on Sludge using D･Box)（多目的技術）(1) D•Box method involves
filling PP bags with crushedstone and other materials for
improvement of soft groundwithout cement. This approach
reduces vibration and CO2.
Moreover, it minimizes
liquefaction damage while
maintaining high permeability
and environmental benefits.
(2) Floods and Tsunami
waves engender the depositionof sludge and debris, blocking
the passage of emergency andconstruction vehicles. By
placing D･Box on top of thissediment during such disasters,
an emergency roadway can beestablished rapidly, ensuring
quick and direct relief routes.
(3) D･Box installations arefilled with materials such as
sludge and concrete rubble.
The surface is layered withsteel plates or planks to allow
vehicles to pass.

Although crushed stone (C40) is preferred as the infill material, onsite natural soil or concrete rubble (φ300 mm or smaller) can also
be accommodated.

HP: Ministry of Land, Infrastructure,
Transport and Tourism: Disaster
Information, Flood Report 2004

Example of sedimented sludge resulting
from an embankment breach

Lifting of the D-Box (1.5 m × 1.5 m ×
0.45 m).

Installation of D-Box on the sludge Internal structure of the D-Box (can belifted from a single point using truss
bands)

Installation of D-Box the sludge

Scaffolding boards used for mitigation(Indonesia)

Disaster damage reduction and environmental impact
reduction ► multi-functional(From Metry Technical Research Institute Co., Ltd.)，
メトリー技術研究所㈱による）Technique for River Basin Disaster Resilienceand Sustainability by All（流域治水技術）

Heavy rain

Ordinary dyke

Dyke with crushed
scallop shells

er
ow
Fl

Crushedscallop layer

Slip line

er
at

GWL

w

in

g

g
in

w

at

soil layerowFlIncreasing
saturation Fine-grained

Crushed scallops might be capable of greenhouse gas (CO2) capture.
(From Professor Kaoru Kobayashi, Ibaraki University, Japan)

－

86

－

Substructure Foundation Scour Monitoring System（ソフト技術）[Technical overview]
This technology remotely monitors scouring statuses of bridge
pier foundations in rivers, enabling data measurement andconfirmation of soundness without visiting the site.
This system determines whether a bridge is passable or notduring a flood and notifies the administrator by e-mail when anabnormality occurs.

[Features]• Requires only on-site installation.
• Installation costs can be reduced depending on the accuracyof detection of changes caused by scouring.
• Thresholds for issuing alerts can be set arbitrarily.

[Effect]• Rapid monitoring of scouring status through constantmonitoring• Ensures safety without being close to substructures, evenduring floods• Supports initial response in the event of a disaster throughnotification of abnormalities by email[Performance]

In Japan, we have track records of data from two nationallymanaged bridges and three prefecturally managed bridges.
We have more than 30 spot measurement records for roadbridges and railway bridges.
Fukuyama Consultants Co., Ltd.

Contact
Information https://www.fukuyamaconsul.co.jp/
m.miyamura@fukuyamaconsul.co.jp (charge: Miyamura)

Strategic Green Infrastructure Promotion Project through Public--Private
Partnership in Moriya City, Ibaraki Prefecture-- Moriya Green Infrastructure Initiative -適応技術例 （ソフト技術）

We are promoting green infrastructure to create a sustainable and prosperous city
by incorporating beautiful nature into daily life.

○POLICY
To use remaining abundant undeveloped city woodland areas,
which are easily accessible from the city center.
Picture: Moriya Yacho no Michi (Wild Bird Path)(Source: Moriya Yacho no Michi Nature Park)

Fukuyama Consultants Co., Ltd.

● The Moriya Green Infrastructure initiative began in November 2017 when Moriya City and Fukuyama
Consultants signed a comprehensive public-private partnership agreement.
● The project is led by the Moriya Green Infrastructure Promotion Council, a public--private consortium
comprising the city and the private sector. The goal is to launch a series of projects based on the policyof green infrastructure in the city through public--private partnership.

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Future Outlook for Climate Change and SDGs
in LRRI （将来展望）♦ Proposal of multi-purpose and multi-functional technologies throughsynergies among different fields, industries, and organizations with different
standpoints such as（融合による多目的で多機能な新しい技術）► Different fields（異なる分野）: Civil engineering, weather information
and ICT► Different industries（異なる業種）: Construction industries, material
industries and energy industries► Different organizations（異なる組織）: Local governments, research
institutes, private sector entities, non-profit organizations, and residents♦ Play roles in local resilience strengthening through synergetic actions（自助，共助，公助推進サポート）on climate change response measuresfrom Japan and overseas➢地域強靭化

Summary♦ How Should We at LRRI Cope with Climate Hazards? （LRRI は気候ハザー
ドのどう立ち向かうか？）► (1) Proposal of interdisciplinary responsive measures usingsynergetic approaches► (2) Increasing technical capabilities through educational support formutual enlightenment♦ LRRI Technologies and Strategies for Climate Change Responses （気候変動対応のためのLRRI関連技術&戦略）► Proposal of multi-purposed and multi-functional technicaldevelopment♦ Future Prospects for Climate Change and SDGs in LRRI （気候変動とSDGs対応の将来展望）► (1) Sharing the roles and responsibilities of construction fields► (2) Contribution to enhancement of local resilience－88－