Emerging trends in seismic Emerging trends in seismic design of geotechnical worksdesign of geotechnical works

Susumu Susumu IaiIaiDisaster Prevention Research InstituteDisaster Prevention Research Institute

Kyoto UniversityKyoto Universityearthquake.mpeg

North AmericanPlate

Pacific Plate

Philippine Plate

Eurasian Plate

1958

1969

1973

1952

1968

1933

1978 M7.4

1938

1953

1923

1944

1946

1964

1993 M7.8

1993 M7.8

1994 M8.1

1994 M7.5

19271925

19431995M7.2

1983 M7.7

Earthquakes Earthquakes and Seismic and Seismic Code Code Development Development （（19641964--19991999））

1993Kushiro

1968Tokachi-oki 1973Nemuro-oki

1983Nihonkai-chubu

1964Niigata

1995Kobe

•• 19641964 Strong motion Strong motion recordingrecording（（Tsuchida/KurataTsuchida/Kurata））

•• 19701970 Liquefaction criterionLiquefaction criterion（（TsuchidaTsuchida））

(1)Liquefaction criterion(1)Liquefaction criterion（（1964Niigata1964Niigata））

(2)Pseudo(2)Pseudo--static methodstatic method（（1968Tokachi1968Tokachi--oki/1973Namuro/1978Miyagioki/1973Namuro/1978MiyagiPGA=0.2PGA=0.2～～0.3g0.3g））

•• 19681968 HachinoheHachinohe（（Tsuchida/KuratTsuchida/Kurataa））

•• 19691969 KatayamaKatayama•• 19741974 MitsuhashiMitsuhashi•• 19751975 Noda et al. Noda et al. •• 19791979 Design Design

codecode 0 0.1 0.2 0.3 0.4 0.5Peak Ground Acceleration (amax/g)

0

0

.1

0

.2

0.

3

Equi

vale

nt S

eism

ic C

oeff

icie

nt k

h

k h = a max

/g

k h = 0.6(a max/

g)

kh = (1/3)(amax/g)1/3

Sakata

Yokosuka

TsumaraYokohama

Aburatsu

Iwafune

Funakawa

Uchiumi

Shimoda

Shimizu

Tokyo

Hachinohe

Aomori W akayama

8 Komatsujima

Shimizu

Takamatsu1 Muroran2 Kushiro

6 Nemuro7 Hanasaki

Miyako

Urakawea

Tokachi Inatori

Sakaide

Uwajima

Hakodate

NohejiKushiro

Pt.Montt

Urakawa

3 Akkeshi4 Uno5

Aklita

Shimoda

Shimizu

Kamakura1

2 3 4 6

8

75

(3)Measures against liquefaction(3)Measures against liquefaction（（1983Nihonkai1983Nihonkai--ChubuChubu））

•• 19841984 ManualManual•• 19841984 Strategic plan Strategic plan

by Ministry of by Ministry of Transport (high Transport (high performance quay performance quay walls)walls)

•• 19891989 Design code Design code (revision)(revision)

(4) Effectiveness of measures (4) Effectiveness of measures against liquefaction)against liquefaction)1993Kushiro/1993Hokkaido1993Kushiro/1993Hokkaido--Nanseioki/1994HokkaidoNanseioki/1994Hokkaido--

Tohooki/1994SanrikuTohooki/1994Sanriku--Harukaoki PGA=0.3Harukaoki PGA=0.3～～0.5g0.5g））

•• 19931993 Effectiveness of Effectiveness of measures against measures against liquefactionliquefaction

•• 19931993 Effectiveness of Effectiveness of seismic design of high seismic design of high embankmentsembankments

•• 19931993 Handbook on Handbook on liquefaction liquefaction remediationremediation

•• 19941994 Effectiveness of Effectiveness of overconsolidationoverconsolidation

High embankment for Kushiro Airport

1.0 5.0 5.0 1.0 2.0+3.6

HWL +1.6LWL +0.0

-7.5Alluvial Clay

Pleistocene Gravel(1)Pleistocene Clay(1)Pleistocene Gravel(2)Pleistocene Clay(2)

Sandy Fill

1.5 ～ 1.7m

after earthquakebefore earthquakeconcave bucklingconvex buckling

Cracking atPile Cap

Alluvial Sand-9.6

-13.1

-16.5-18.5-16.7

-11.9

Pile Thickness Change

3%tilting

HorizontalDisplacement

Rubble

(5)Performance based design(5)Performance based design（（1995Hyogoken1995Hyogoken--Nambu PGA=0.5Nambu PGA=0.5～～0.8g0.8g））

•• 19951995 Numerical analysis/underwater Numerical analysis/underwater shake table testsshake table tests

•• 19971997 Level 1&2 earthquake motionsLevel 1&2 earthquake motions•• 19971997 Performance design for Performance design for

liquefaction remediationliquefaction remediation(Handbook on liquefaction remediation (Handbook on liquefaction remediation

(revised))(revised))•• 19971997 FLIP open to public use (Finite FLIP open to public use (Finite

element code for evaluating degree of element code for evaluating degree of damage to soildamage to soil--structure systems)structure systems)

•• 19981998 Strong motion recording for Strong motion recording for airportsairports

•• 19991999 Liquefaction remediation for Liquefaction remediation for airport runway (Tokyo International airport runway (Tokyo International Airport)Airport)

•• 19991999 Design code (revision) Design code (revision)

0.004m1.20m 1.20m

0.10m

+0.0m

-7.5m

-25.0m

Emerging Trends in Seismic Design Emerging Trends in Seismic Design of Geotechnical Works (2000of Geotechnical Works (2000～）～）•• Imminent Large Earthquakes (Government)Imminent Large Earthquakes (Government)•• Strong motion recordsStrong motion records→→ Scenario earthquake motionsScenario earthquake motions（（NozuNozu））

•• Digital data of earthquake motions open to publicDigital data of earthquake motions open to public（（Nozu/KurataNozu/Kurata））

中央防災会議HPより

Performance Based DesignPerformance Based Design

•• Structure orientedStructure oriented→→ Performance orientedPerformance oriented•• Standardized earthquake loadsStandardized earthquake loads（（Seismic Seismic

coefficient/Design spectracoefficient/Design spectra））→→ SiteSite--specific specific earthquake motionsearthquake motions

•• Analysis of Structural PartAnalysis of Structural Part→→ Analysis of SoilAnalysis of Soil--Structure SystemStructure System Simplified analysis: Simplified analysis: Detailed analysis:Detailed analysis:Simplified analysis: Simplified analysis: Detailed analysis:Detailed analysis:

Firm LayerFirm Layer

Loose SubsoilLoose Subsoil

Firm FoundationFirm Foundation

On Firm Foundation

Loose Saturated Sandy Foundation

Failure modes

Globalization and seismic code Globalization and seismic code developmentdevelopment earthquake.mpeg

•• Handbook on liquefaction remediation Handbook on liquefaction remediation 19971997

•• UBCUBC→→IBC 2000IBC 2000•• PIANC Seismic Design Guidelines for Port PIANC Seismic Design Guidelines for Port

Structures 2001Structures 2001•• ISO23469 Seismic Actions for Designing ISO23469 Seismic Actions for Designing

Geotechnical Works 2005Geotechnical Works 2005•• USA/NEES Grand Challenge Program 2006USA/NEES Grand Challenge Program 2006

Global Seismic Hazard Assessment Program GSHAP

http://seismo.ethz.ch/GSHAP/

NEHRP http://eqhazmaps.usgs.gov/

Postal code search

MCE Ground Motion Map

IBC2000

MCE

NEHRP

EurocodeEurocode 8 Design of structures for 8 Design of structures for earthquake resistanceearthquake resistance

•• Part 1: General rules, seismic actions and rules Part 1: General rules, seismic actions and rules for buildingsfor buildings

•• Part 2: BridgesPart 2: Bridges•• Part 3: Strengthening and repair of buildingsPart 3: Strengthening and repair of buildings•• Part 4: Silos, tanks and pipelinesPart 4: Silos, tanks and pipelines•• Part 5: Foundations, retaining structures and Part 5: Foundations, retaining structures and

geotechnical aspectsgeotechnical aspects•• Part 6: Towers, masts and chimneysPart 6: Towers, masts and chimneys

Fundamental requirementsFundamental requirements

Fundamental requirementsFundamental requirements

The facilities fall into five general categories: Shaking tables

Tsunami wave basinGeotechnical centrifuges

Field experimentation and monitoringLarge-scale laboratory experimentation

Network for Earthquake Network for Earthquake Engineering Simulation (NEES) Engineering Simulation (NEES)

Emerging trendsEmerging trends（（ConstructionConstruction→→ ServiceService））Seismic design of urban systemSeismic design of urban system

•• Digital data of strong Digital data of strong motion open to motion open to public(Nozu/Kurata)2001public(Nozu/Kurata)2001

•• Oil tank damage 2003Oil tank damage 2003•• Blast experiments of Blast experiments of

urban system in urban system in Tokachi(Sugano)2004Tokachi(Sugano)2004

•• Emergency system Emergency system (Access and deployment)(Access and deployment)

•• RealReal--time monitoring for time monitoring for hazard mitigation

1964Niigata

1995Kobe

hazard mitigation

2003Tomakomai（after Mainichi）

Source: Digitalglobe Analysis

Grand MosquePort Mosque

Emerging trendsEmerging trends（（Measures for wide area and Measures for wide area and combined hazardscombined hazards））•• Combined hazards Combined hazards

((tsunami+earthquaketsunami+earthquake) ) ((flood+earthquakeflood+earthquake))

•• Coastal facilities (long) Coastal facilities (long) →→ Design chart systemDesign chart system20052005

Coastal facilitiesCoastal facilities（（Coastal protection Coastal protection →→Coastal serviceCoastal service））

New type

▽ LWL +0.00

ハーバーウォーク

10m 20m

▽2.67

HWL = +1.70

背 後 緑 地 官民境界

▽4.70

▽ HWL +1.70▽ HWL +1.70

▽3.80

標準断面図

想定津波高▽KP+2.8▽+2.50

Kobe City

Conventional type

Future directionsFuture directions（（Cost reductionCost reduction→→ Service increaseService increase））

•• ConstructionConstruction→→ PerformancePerformance•• PerformancePerformance→→ Developing new serviceDeveloping new service

e.g.e.g.））Built environmentBuilt environment（（urban systemurban system））, Natural , Natural environmentenvironment（（bio systembio system））

•• Steel & concreteSteel & concrete→→ New materials and ITNew materials and IT•• Combined engineering (Hard/soft)Combined engineering (Hard/soft)•• MaintenanceMaintenance→→ Renovation/RedevelopmentRenovation/Redevelopment•• Seismic designSeismic design→→ Creating a space of safety and Creating a space of safety and

securitysecurity

Egypt

Singapore

Dubai

ConclusionsConclusions

•• Design for construction Design for construction →→ Design for Design for performanceperformance

•• Standardized approach Standardized approach →→ SiteSite--specific approachspecific approach•• Segment (structure or soil part) design Segment (structure or soil part) design →→

System (soilSystem (soil--structure system) design structure system) design →→ Built Built environment designenvironment design

•• Cost reduction Cost reduction →→ Service increaseService increase•• Emerging trends appropriate for rEmerging trends appropriate for rapidlyapidly growing growing

social and economic needs in Asiasocial and economic needs in Asia