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2016-7

Joint ICTP/IAEA Advanced Workshop on Earthquake Engineeringfor Nuclear Facilities

Hiroshi Abe

30 November - 4 December, 2009

Japan Nuclear Energy Safety OrganizationSeismic Safety Division

TokyoJapan

Outline of seismic regulation on NPPsand

Seismic safety re-evaluation in Japan

1

Incorporated Administrative Agency Incorporated Administrative Agency Japan Nuclear Energy Safety Organization Japan Nuclear Energy Safety Organization

ICTP/IAEA Advanced Workshop on Earthquake Engineering for ICTP/IAEA Advanced Workshop on Earthquake Engineering for Nuclear FacilitiesNuclear Facilities

Outline of seismic regulation on NPPsOutline of seismic regulation on NPPsand and

Seismic safety reSeismic safety re--evaluation in Japanevaluation in Japan

Dec. 1Dec. 1 20092009

Hiroshi AbeHiroshi Abe

Incorporated Administrative Agency Incorporated Administrative Agency

Japan Nuclear Energy Safety Organization (Japan Nuclear Energy Safety Organization (JNESJNES))Seismic Safety DivisionSeismic Safety Division

2


ContentFormation of seismic regulation in JapanFormation of seismic design code in JapanOutline of ;

- 1 Seismic Design Review Guide(JNSC); comparing Before and Revised

-2 Technical Guidelines forSeismic design of NPP(JEAG4601)

Status of Seismic Assessment

-1 Kashiwazaki-Kariwa NPPs

-2 Re-evaluation of other NPPs

3


Seismic Safety Regulation System in Japan

● Hyogo-Ken Nambu Earthquake (1995.1)

Miyagi-Oki Earthquake (2005.8) - Onagawa NPPs Shut Down

Revision of Safety Review Guideline for Seismic Design (NSC: 2006.9)

Noto-Hanto-Oki Earthquake (2007.3) - Shika NPPs

Under Shut Down StateNiigata-Ken Chuets-Oki Earthquake

(2007.7)- Kashiwazaki-Kariwa NPPs Shut Down

● Suruga-Bay Earthquake (2009.8)- Hamaoka NPPs Shut Down

● HyogoHyogo--Ken NambuKen Nambu Earthquake (1995.1)

MiyagiMiyagi--OkiOki Earthquake (2005.8) - Onagawa NPPsOnagawa NPPs Shut DownShut Down

Revision of Safety Review Guideline for Safety Review Guideline for Seismic DesignSeismic Design (NSCNSC: 2006.9)

NotoNoto--HantoHanto--OkiOki Earthquake (2007.3) - Shika NPPsShika NPPs

Under Shut Down StateUnder Shut Down StateNiigataNiigata--Ken ChuetsKen Chuets--OkiOki Earthquake

(2007.7)- KashiwazakiKashiwazaki--Kariwa NPPsKariwa NPPs Shut DownShut Down

●● SurugaSuruga--BayBay Earthquake (2009.8)Earthquake (2009.8)-- Hamaoka NPPsHamaoka NPPs Shut DownShut Down

Resent Events Related EarthquakesResent Events Related Earthquakesand Seismic Safety of NPPsand Seismic Safety of NPPs

Seismic Safety Div.(established Oct.2007)

Seismic safety reviewing office(established April 2004)

9 Electric Power companiesJapan Electric Association

4


Formation of seismic design code in JapanNuclear Safety Commission・Regulatory Guide for Reviewing Seismic Design of NPP (15pages) →1981July Established

2006 Sept. Revised

METI (Nuclear and Industrial Safety Agency)・Ministry Code No62 “Technical code for

NPP Article5 Seismic requirement”

Japan Electric Association (Utilities)・Technical Guidelines for Seismic Design of NPPs

JEAG4601 (～1300pages) (English version: NUREG/CR-6241)→1970,1984,1987,1991 Completed gradually

Now revising

5


Outline of ;-1 Japan Nuclear Safety Commission’s;

Seismic Design Review Guidecomparing Before and Revised

6


S (old As and A), B, COld A class ranked up to As

As, A, B, CSeismic Seismic ClassificationClassification

ConsiderConsider the effect of;the effect of;・・Tsunami,Tsunami,・・Collapse of around inclined planeCollapse of around inclined plane

Phenomena Phenomena accompanying accompanying earthquakeearthquake

Possibility of over DBE earthquake cannot be denied. ・Risk by over DBE causing serious damage to SSCs and massive radioactive release is to beassessed for reference (Residual Risk)・Utilities should evaluate the risk for reference

and make effort to minimize the risk.

Over DBEOver DBEEarthquakeEarthquake

Define Fv dynamicallyFv= 1/2 FH (Static)‏Consideration of Consideration of Vertical Seismic Vertical Seismic ForceForce

Use most updated knowledge and techniqueGeological Geological SurveySurvey

・One DBE Ss: Consider active fault hereafter

late Pleistocene (80000-130000y before)Keep function＊

・Sd for design to stay in elastic region＊Sd=α×Ss ; α0.5

＊Class S component

・S1: Return period more than 10000yStay in elastic region＊

・S2: Return period more than 50000yKeep function＊

＊ Class As、A component

Design Base Design Base Earthquake Earthquake DefinitionDefinition

RevisedBeforeItem

■■ Main points of the revisionMain points of the revision

7


Basic Earthquake Ground Motion Ｓ1




BeforeBefore

RevisedRevised

Active Faults

Past Earthquakes

Seismo-tectonic Features

Intra-plate Earthquakes

Basic Earthquake Ground Motion SsBasic Earthquake Ground Motion Ss

Inter-plate Earthquakes

Ground m

otion EvaluationG

round motion Evaluation

Considered Earthquakes（①）

Ground m

otion EvaluationG

round motion Evaluation

Considered Earthquakes（①）

（Horizontal componentonly）

Both Horizontaland Vertical

（②）（②）

（③）

（③）

（④）

（④）

Near Field Earthquake

Maximum Design Earthquake

Extreme Design Earthquake

Shallow Inland Earthquakes

Design Earthquake Ground Motion SdDesign Earthquake Ground Motion Sd

Site-specific Ground motionwith specified source

Ground motion with non-specified source

■■ DBE Definition DBE Definition -- Earthquake Research FlowEarthquake Research Flow

8


BeforeBefore

RevisedRevised

Active Faults

Past Earthquakes

Seismo-tectonic Features

c. Intra-plate Earthquakes

a. Inter-plate Earthquakes

b. Shallow Inland Earthquakes

・Earthquake documents・Active faults research・Seismicity near site

Consider with each research methods

Consider with each source type

DBE Definition DBE Definition -- Earthquake ConsiderationEarthquake Consideration

9


BeforeBefore

RevisedRevised

Empirical methods (Response spectrum evaluation)

Empirical methods + Strong motion evaluation using Earthquake source model→Reflected in IAEA seismic hazard evaluation guide DS422

Point source

Consider the effects of the fault plane

Evaluate the Ground motion directly

DBE Definition DBE Definition –– Ground Motion EvaluationGround Motion Evaluation

10


BeforeBefore

RevisedRevised

Consider NearConsider Near--field Earthquake field Earthquake

(M6.5, 10km beneath the site) (M6.5, 10km beneath the site)

周期（s）

擬似

速度

応答

スペ

クト

ル(c

m/s)

0.01 0.1 1 10

1

10

100

Estimate the upper level of the ground Estimate the upper level of the ground motion difficult to specify the source by motion difficult to specify the source by survey in the vicinity of the sitesurvey in the vicinity of the site

→→Estimate directly on the basis of Estimate directly on the basis of nearnear--source strong motion recordssource strong motion records

周期（s）

擬似

速度

応答

スペ

クト

ル(c

m/s)

0.01 0.1 1 10

1

10

100

DBE Definition DBE Definition –– NearNear--Field EarthquakeField Earthquake

11


BeforeBefore

RevisedRevised

Consider the active faults that has activity in 50,000 yearsConsider the active faults that has activity in 50,000 years

For Ss, consider the active faults that has activity in the lateFor Ss, consider the active faults that has activity in the late PleistocenePleistocene（（referring to last Interglacial stratareferring to last Interglacial strata［［about 80,000 about 80,000 –– 130,000 years before130,000 years before］）］）

Active Fault of Low activity (Return period more than 50,000 Active Fault of Low activity (Return period more than 50,000 ））→→ Consider as the source of SConsider as the source of S22

Active Fault of high activity (Return period more than 10,000 Active Fault of high activity (Return period more than 10,000 ））

→→ Consider as the source of SConsider as the source of S11

Consider as the source of Inland Earthquakes for SsConsider as the source of Inland Earthquakes for Ss

Active Faults ConsiderationActive Faults Consideration

12


BeforeBefore Based onBased on Aerial photo, Trench, Aerial photo, Trench, ・・・・・・・・・・

Active Faults assessmentActive Faults assessment

13


Adding advanced active faults assessment methodology : Geomorphology, Topography

Fault-bend fold

Suppe et al. (1992)

Active anticline

Okamura, Active Fault Research Center AIST,2008

RevisedRevised

14


InIn--landlandSeismic profiling by controlled Seismic profiling by controlled seismic sourceseismic source

Seismic ProfilingSeismic Profiling

OffOff--shoreshoreSupersonic wave surveySupersonic wave survey・・More deep beneathMore deep beneath

the sea bottom can bethe sea bottom can besearchable nowsearchable now

Geological SurveyGeological SurveyRequirement for Requirement for most updated technique and more most updated technique and more

detailed surveydetailed survey in the vicinity of the sitein the vicinity of the site

RevisedRevised

15


BeforeBefore

RevisedRevised

Consider Vertical Seismic Force as Consider Vertical Seismic Force as ½½ as Horizontal, staticallyas Horizontal, statically

Consider Both Horizontal and Consider Both Horizontal and Vertical Seismic Force dynamicallyVertical Seismic Force dynamically

Dynamic

Dynamic

Consideration of Vertical Seismic ForceConsideration of Vertical Seismic Force

16


BeforeBefore

RevisedRevised

CBA

As

4 classes

RPV, PCV etc.

ECCS, RHRS etc.

Main Turbine System etc.

Other Facilities

3 classes

CBS

Ａs … Designed with Ｓ2

also designed with Ｓ1

Ａ … Designed with Ｓ1

（Maintains Safety Function）

（Remains within Elastic limit）

S … Designed with Ｓs

also designed with Ｓd（Maintains Safety Function）

Ａ and As classes are integrated into S class



■■ Seismic ClassificationSeismic Classification

Sd＝α×Ss , α0.5

17


■ Consideration to the phenomena accompanying earthquake

The concrete demand is not describedThe demand to the natural disaster of a landslide, tsunami or

high tide, and others is specified independently.

BeforeBefore

RevisedRevised

• Influence of the safety function on the ｆacilities by collapse of a circumference slope

(2) Influence of the safety function on the ｆacilities by tsunami

Followings should be taken into account in the seismic design

The maximum height of tsunami ＋ The water level at the time of high water

�Height of installation of plant �Water proof design ｏf

facilities or equipment etc

The minimum water level of tsunami �Management by the design

of facilities or equipment etc

18


JEAG 4601-1987 (’87 ver.)To show concrete methods about geological surveys, establishment of design base earthquake, assessment of ground stabilities, seismic designs for buildings / structures and components.

To show the policy about seismic classifications, relations between operation situations and earthquakes, allowable stress and so on.

JEAG 4601-1991 additional version (’91 ver.)

To add to ’87 ver. Definition of dumping factor of facilities and methods of seismic assessment of dynamic components.

JEAG 4601 Supplementary-1984Seismic Importance Classifications & Allowable Stress version (’84 ver.)

-2 Outline of the Outline of the JEAG 4601JEAG 46011. History1. History

19


2. Classifications2. Classifications

House Boiler,Make- up Water System, etc

Facilities that should keep safety as same as general industrial facilities, except S and B class

CClass

Main Turbine,Radioactive WasteTreatment Systems, etc

Facilities that have low effects compared with the above-mentioned ones

BClass

• Reactor Pressure Vessel, etc

• Primary Containment Vessel, SHC System, etc

• Reactor Building, etc

Facilities including radioactive materials inside or facilities connected to them directly. 1. To bring about emission of radioactive materials outside by loss of those functions.2. To be needed to prevent from occurrence of such situations as described above (at 1.). 3. To be needed and very effective to reduce the effects by radioactive materials diffused outside

SClass

ExamplesDefinitionClass

20


Input Motion for Buildings

○ Modeling of Soil aboveBase Stratum*

○ Input Design Base Earth-quake to Base Stratum*

○ Evaluation of Input-Motionon Building Level

Design Base Earthquake

Base Stratum

Input Motion

3. Specimens of Design Methods 3. Specimens of Design Methods 3.1 Structures3.1 Structures

* Base Stratum : Vs ～700m/s

Wave

Propagation

Model of

Soil

21


Shear-Beam Modeling of Building

○ Consolidates each mass of each facility and building structure to the floor Level

○ Evaluate Stiffness of Column & Bearing-Wall against Bending-Moment & Shear Force

22


Response Analysis of Building

○ Modeling of Building

○ Input Ground-Motion fromAnalysis of Soil

○ Evaluate Response of Each Floor

23


Stress must be below allowable stressDeformation must be below allowable deformationShear strain must be below allowable strain for Ss

Stress

Collapse

Maximum Load

Linear AreaAllowable Strain for Ss

Shear Strain

Limit Strain

24


Beam Element (Wall) ‏

Mass-Stiffness Model 3-D FEM Model

■ Mass-Stiffness Modeling■ FEM Modeling

質点Mass

Beam Element(Wall) ‏

Beam Element(Floor)‏Mass

25


In many case of Class S structures, Static force 3Ci* are dominant force for design.Wall and slab of NPP Class S structures are much thicker than general buildings.

* 3Ci : 3 times of for general building

26


2 Facilities2 Facilities

Spectrum Modal AnalysisSpectrum Modal Analysis

4. Response Analysis

of the Building

3. Input the DBE into the Building, Taking into

Account of the Ground

2. Design Base Earthquake 1. Target Spectrum of DBE

Design FRS FRS

6. Dynamic Design Analysis of Components Based on their Own Proper Periods

5. Making of FRS for Reasonable Evaluation of Components

27


Time Historical AnalysisTime Historical Analysis

Time (s)

Input DBE wave

Acc

eler

atio

n (G

al‏(

CRD Guide Tube

CRD Housing

Fuel Assembly

Separator

Reactor Pressure Vessel (RPV)

RPVStabilizer

PCVStabilizer

Rea

ctor

Bui

ldin

g

Diaphragm Floor

Shro

ud

The

rmal

Wal

l

Earthquake responses of some components around reactor are evaluated as a coupled system with the building and the ground.

28


Piping SystemsPiping Systems

RPV

Response Stress Allowable Stress<

Evaluation

Dynamic Design Analysis of equipments based on their own proper periods

Own Proper Periods (s)Res

pons

e A

ccel

erat

ion

(G)

Input

Allowable Stressex.Allowable stress state AS ： 2.25SmAllowable stress state AS ： 3Sm

29


. Status and Example of Seismic Assessment on NPPs

-1 Kashiwazaki NPP Case

JNES-USNRC/RES, 26 August 2009 Meeting 30


Location of Kashiwazaki-Kariwa Nuclear Power StationLocation of Kashiwazaki-Kariwa Nuclear Power Station

５００m０



Outline of the Chuetsu-oki EarthquakeOutline of the Chuetsu-oki Earthquake

- The Niigataken Chuets-oki (NCO)Earthquake in 2007- July 16, 2007 10:13 a.m. JST (01:13 UTC)- Epicenter: 16 km from Kashiwazaki-Kariwa NPP site

- Hypocenter: 17 km below the seabed off Jo-Chuetsu area, Niigata prefecture

- Magnitude: 6.8 (JMA Magnitude)

©Google ©ZENRIN

10km

30km

Epicenter

KK site

10km

30km

Epicenter

KK site



Seismic Response of each unit Seismic Response of each unit

３５５（２３５）

３５６（２６３）

２６７（２６３）

Unit #7

４８８（２３５）

３２２（２６３）

２７１（２６３）

Unit #6

２０５（２３５）

４４２（２５４）

２７７（２４９）

Unit #5

３３７（２３５）

４９２（１９４）

３１０（１９３）

Unit #4

３１１（２３５）

３８４（１９３）

３０８（１９２）

Unit #3

２８２（２３５）

６０６（１６７）

３０４（１６７）

Unit #2

４０８（２３５）

６８０（２７３）

３１１（２７４）

Unit #1

VerticalComponent

East-WestComponent

North-SouthComponent

Numbers shown in ( ) are the design values.

Observed Peak Acceleration at Lowest Floor of Reactor Building

(gal = cm/sec2)



Plant behavior at and immediately after the earthquake・All three units in operation (#3,#4,#7) and one unit in start-up (#2) were shut down by seismic switches.

・All units received the earthquake response greatly exceeding the design values, all four units in operation and start-up were led to the cold-shut-down state by normal procedure.

・In spite of a big earthquake, three lines (temporary two )of four of external power supply were secured, and as the result there was no starting of emergency DGs

（About EDGs, start-up tests were carried out promptly from their importance, and functional soundness were confirmed for all EDGs.

・There were many non-safety SSCs troubles such as yard road damages, fire-extinguishing piping damages in yard, fire of in-house transformer for #3, release of very small amount of radioactive material.

Situation Immediately after the Earthquake

Shift of duct connection to main stack （Units １ - ５）（Seismic class C)

House transformer fire at Unit 3, (Seismic class C)

Road damage in the site



Unit 6 & 7 : No significant abnormality caused by the EQ was found

Scheme of integrity evaluation after the EQ by TEPCO and NISA/JNES

（NISA action）

TEPCO report

（TEPCO action）

Safety Equipment Other equipment ・Review of evaluation plan・Review of insp. method for equipment types (through safety inspection etc.）

Review by governmental committees

Review by on-site inspection etc.

Evaluation by cross-check by JNES

Final evaluation based on committees review, on-site

inspection etc.

Basic inspection

Inspection/evaluation plan

Input to final evaluation

Insp./Anal.

Seis. analysis

Additional insp.

Additional insp./anal. directed by

NISA

Evaluation

Status report

Report

(if required）



Investigation and Evaluation System of the Government 【 Investigation Items 】 Assessment of :• Seismic safety based on the insight gained from the NCO EQ.• Operational management and facilities integrity at the NCO EQ./future actions• In-house fire brigade system, information network and its distribution system at NCO EQ.

Nuclear and Industrial Safety Agency (NISA)

Operation Management / Facilities Integrity Evaluation WGSet-up: 4 Sep. 2007Leader: Naoto Sekimura, Prof. The University of Tokyo

Working Group on the Review of In-house Fire Brigade Systems and Emergency Information / Public Communications in NCO EQSet-up : 27 Aug. 2007Leader: Hirotada Ohashi, Prof. Dept of Quantum Engineering and Science,The University of Tokyo

Report

Subcommittee for the Investigation and Response to the Facilities Affected by NCO EQ Set-up: 31 Jul. 2007Chairperson：Haruki Madarame, Professor, Graduate School of the University of Tokyo

The Investigation in Seismic and Structural Design Subcommittee Set-up: Nov. 2005Leader：Katsumasa Abe, Professor Emeritus, The University of Tokyo

（Established before the Quake）

Facilities Integrity Evaluation Sub-WG Set-up: 12 Nov. 2007Leader: Naoto Sekimura, Prof. The University of Tokyo



Investigation and Evaluation System of the GovernmentInvestigation and Evaluation System of the Government( Safety Evaluation of Kashiwazaki and Back( Safety Evaluation of Kashiwazaki and Back--check for Revised Seismic Guide)check for Revised Seismic Guide) ‏‏


Operation Management / Facilities Integrity Evaluation WGSet-up: 4 Sep. 2007Leader: Naoto Sekimura, Prof. Univ. of Tokyo

WG on the Review of In-house Fire Brigade Systems and Emergency Information / Public Communications in NCO EQSet-up : 27 Aug. 2007Leader: Hirotada Ohashi, Prof., Univ. of Tokyo

Subcommittee for the Investigation and Response to the Facilities Affected by NCO EQSet-up: 31 Jul. 2007Chairperson：Haruki Madarame, Prof., Univ. of Tokyo

Facilities Integrity Evaluation Sub-WG Set-up: 12 Nov. 2007Leader: Naoto Sekimura, Prof. Univ. of Tokyo

The Investigation in Seismic and Structural DesignSubcommitteeSet-up: Nov. 2005Leader：Katsumasa Abe, Professor Emeritus, Univ. of Tokyo Report

Structural WGSet up : 13 Sept. 2007Leader：Takao Nishikawa, Prof. Emeritus, Tokyo Metropolitan Univ.( Kasiwazaki, Hamaoka )‏

Earthquake/Tsunami, and Geology/Foundation joint WG

Set up: 12 Oct. 2007Leader:Katsumasa Abe, Prof. Emeritus, Univ. of Tokyo( Kasiwazaki, Hamaoka )‏

A Sub-GSet up : 14 April 2008Leader : Yoshihiro Kinugasa, Prof. Tokyo Institute Tech. ( Tomari, Fukusima 1 and 2, Tokai 2, Ikata, Tokai Reprocess Faci. ）

B Sub-GSet up : 28 April 2008Leader : Saburo Midorikawa, Prof. Tokyo Institute of Tech.( Higasidori, Onagawa, Shimane, Genkai, Sendai, Rokkasyo Reprocess Faci.）

C Sub-GSet up 11 April 2008Leader : Kazuki Koketsu, Prof. Univ. of Tokyo( Shika, Tsuruga, Mihama, Takahama, Ohii, Monjyu ) ‏

A Sub-GSet up : 13 May 2008Leader : Tetsuo Kubo, Prof., Univ. of Tokyo( Tomari, Higasidori, Onagawa, Fukusima 1 and 2, Tokai 2, Shika, Ikata )‏

B Sub-GSet up : 21 April 2008Leader : Takao Nishikawa, Prof. Emeritus, Tokyo Metropolitan Univ.( Tsuruga, Mihama, Takahama, Ohii, Shimane, Genkai, Sendai, Monjyu ）

耐震・構造設計小委員会中越沖地震における原子力施設に関する調査対策委員会

運営管理・設備健全性評価WG

自衛消防及び情報連絡・提供に関するWG

設備健全性評価サブWG

地震･津波、地質・地盤合同WG構造WG

Special committee for KasiwazakiMandate: Assessment of• Seismic safety based on the insight gained from the NCO EQ• Operational management and facilities integrity at the NCO

EQ./future actions• In-house fire brigade system, information network and its

dissemination system at NCO EQ

C Sub-GSet up : 20 May 2008Leader : Takao Nishikawa, Prof. Emeritus, Tokyo Metropolitan Univ.（ Rokkasyo Reprocess Faci., Tokai Reprocess Faci. ）



Outline of NISAOutline of NISA’’s Interim s Interim Report Report

on NISAon NISA’’s Action and Results s Action and Results for Seismic Safety of KK Sitefor Seismic Safety of KK Site

( 13 February 2009 )



Evaluation of Operation/Management of Facilities at/after NCO EarthquakeEvaluation of Operation/Management of Facilities at/after NCO EaEvaluation of Operation/Management of Facilities at/after NCO EarthquakerthquakeWorking Group on the Operational Management and Evaluation of the Facilities Integrity

• Evaluation of three fundamental safety functions : They were maintained because four plants which were in operation or start-up condition were shut down by seismic triggers and maintained cold shut down condition and there was no abnormality of fuel bundles.

(2) Although there was no EDG start-up at NCO earthquake (because external power lines were secured), there was no abnormality on EDGs in start-up/operation tests after earthquake. Therefore emergency power source was evaluated to be secured.

Rel

ativ

e di

spla

cem

ent

of fu

el b

undl

e (a

naly

sis,

mm

‏(

Signal of “Large Seismic Accel.”

About 2 sec.

Full insertion of CRs

Max. relative displacement of fuel bundle

NS Direction

EW Direction

Time

Insertion time evaluation of control rods for K-7



From Working Group on the Review of In-house Fire Brigade System and Emergency Information /Public Communication

（３）Events that should be referred on other NPPs amongthe troubles caused by the Quake

Management of temporary articles etc. used in annual inspection is required（Management that prevent damages on importantpiping etc. by the displacement of heavy temporaryequipment and shielding blocks etc. in necessary）Preparation of manual that assumes cases where processing that exceeds capacity of exit monitor inemergency is neededConfirmation and management of the state of setting of fuel bundle on fuel support when loading

（４）Release of extremely small amount of radioactive substance immediately after the EQPrevention by training curriculum development etc. isnecessary assuming the effect of fuel pool sloshing, abnormal plant shut-down etc.

Evaluation of Operational Management at/after the EQEvaluation of Operational Management at/after the EQ-- Example of Extracted Cases and Lessons Example of Extracted Cases and Lessons --

Damage on SLC piping thermal insulator due to the movement of ultra sonic test equipment



Enhancement of In-house Fire BrigadeEnhancement of InEnhancement of In--house Fire Brigadehouse Fire Brigade

• Enhancement of Initial extinction capability- System construction on 24 hour standing and

education of leaders2. Improvement of reliability of firefighting

equipment- Diversification and multiplexing by

earthquake secured firefighting equipment, chemical fire engine deployment, and additional deployment of fire water tanks and large fire extinguishers

• Reliability improvement of communication tools etc. necessary for firefighting operation

• Pragmatic training with public firefighting organization

•• Enhancement of Enhancement of Initial extinction capabilityInitial extinction capability-- System construction on System construction on 24 hour standing and 24 hour standing and

education of leaderseducation of leaders2.2. Improvement of Improvement of reliability of firefighting reliability of firefighting

equipmentequipment-- Diversification and multiplexing by Diversification and multiplexing by

earthquake secured firefighting equipment, earthquake secured firefighting equipment, chemical fire engine deployment, and additional chemical fire engine deployment, and additional deployment of fire water tanks and large fire deployment of fire water tanks and large fire extinguishersextinguishers

•• Reliability improvement of Reliability improvement of communication communication toolstools etc. necessary for firefighting operationetc. necessary for firefighting operation

• Pragmatic training with public firefighting organization

Required improvement by the WG on Fire Brigade and Comm.（Report on Feb. 2008）

Required improvement by the WG on Fire Brigade and Comm.（Report on Feb. 2008）

• Additional requirement to improve initial extinction system in commercial reactor law

• Additional requirement to enhance extinction equipment in NISA’s ordinance- Diversification, multiplexing, reliability improvement of fire water tanks and piping, and deployment of large fire extinguishers etc.

• Additional requirement to improve initial extinction system in commercial reactor law

• Additional requirement to enhance extinction equipment in NISA’s ordinance- Diversification, multiplexing, reliability Diversification, multiplexing, reliability improvement of fire water tanks and piping, improvement of fire water tanks and piping, and deployment of large fire extinguishers and deployment of large fire extinguishers etc.etc.

Improvement of related laws etc.Improvement of related laws etc.



Effort and Preparation Required in Communication of Information to the Public in Emergency

Effort and Preparation Required in Communication of Information to the Public in Emergency

When a severe earthquake occurs, it is important to offer information of NPP situation promptly, and to offer necessary information like necessity of evacuation to the vicinity residents accurately

When a severe earthquake occurs, it is important to offer information of NPP situation promptly, and to offer necessary information like necessity of evacuation to the vicinity residents accurately

• Prompt information deliverance by using various means• Plain expression to so that the public understand easily• Enhancement of site aiming structure in the government• Improvement of telecommunication equipment and system by

utilities when large earthquake• Implementation of practical drill and training

• Prompt information deliverance by using various means• Plain expression to so that the public understand easily• Enhancement of site aiming structure in the government• Improvement of telecommunication equipment and system by

utilities when large earthquake• Implementation of practical drill and training

• Effective improvement plan of ideal way to make public when abnormality occurs

• Securing transparency of information and effort to disseminate proper knowledge to the public

• International sharing of finding and knowledge learned

• Effective improvement plan of ideal way to make public when abnormality occurs

• Securing transparency of information and effort to disseminate proper knowledge to the public

• International sharing of finding and knowledge learned

Recommendation by the In-house fire brigade WGRecommendation by the

In-house fire brigade WG

Comment by NSCComment by NSC



Integrity Evaluation of KK Site - Focusing on Unit 7 -



NISA’s review result of KK-7 after receiving NCO EQ (As of Feb. 2009）

(1) Following inspections and tests were completed for about 1,360 equipment which were examined in the construction permit, and no issue was confirmed.

• Visual inspection for about 1,360 equipment• Function tests for about 1,000 equipment• Leak tightness tests for about 610 equipment

However, although it was evaluated as no relation with the EQ, cracks were found at rotor blades of LPT which was evaluated as fatigue developed at performance test and replacing work is performed.

(2) Inspection results of buildings and structures• R/B and T/B : It was confirmed that the earthquake-resistance strength, a

shielding function are maintained because no crack of over 1mm width was identified, which is used as inspection standard, therefore

• Stack : It was confirmed that the earthquake-resistance strength was secured

• Emergency intake canal : It was confirmed that there is no damage that disturbs the intake function for the emergency water.



The Investigation in Seismic and Structural Design Subcommittee Leader：Katsumasa Abe, Professor Emeritus, The University of Tokyo


Earthquake/Tsunami, and Geology/Foundation joint WG

Leader：Katsumasa Abe, Professor Emeritus, The University of Tokyo

Sub-group A, B, C

(1) Active Fault Evaluation

・Off-shore fault：F-B fault was newly evaluated as active (36km）

・Land fault：Simultaneous activity of fault zone of western margin of Nagaoka Plane was considered (Total length : 91km)

(2) Evaluation of New Design Basis Ground Motion (Ss)

・#1 – 4 : 2,300gal

・#5 – 7 :1,209gal

Annual exceedance probability:10-4～10-5

（３）NSC evaluated that newly defined Ss is adequate （Dec. 2008)

Seismic Safety Evaluation for KK site ( For the Revised Reviewing Guide )

( for KK and Hamaoka sites )

( for other 18 sites than KK and Hamaoka including re-processing sites )



The Investigation in Seismic and Structural Design SubcommitteeLeader：Katsumasa Abe, Professor Emeritus, The University of Tokyo


(1)Building and Structure

・Shear deformation of R/B,T/B,C/B : less than 10-2

・Emergency intake structure: less than the allowable

(2) Equipment and Piping

・Physical strength improvement : Reinforcement and evaluation based on 1,000gal response on the base mat.

・Evaluation result : less than design allowable

・Active component : less than test certified acceleration

Seismic Safety Evaluation for KK site ( For the New Design Ground Motion based on the Revised Reviewing Guide )

Structural work groupLeader：Takao Nishikawa, Professor Emeritus, Tokyo Metropolitan University

Sub-working group A, B, C.

( for KK and Hamaoka sites )

( for other 18 sites than KK and Hamaoka including re-processing sites)



Assessment of the Seismic SafetyBased on the Insights Gained from

the Chuetsu-oki Earthquake



Key Review Items by NISA to Secure Seismic Safety of Kashiwazaki-Kariwa Nuclear Power Station

1. Is seismic safety of Kashiwazaki-Kariwa Nuclear Power Station

secured against the earthquake？

2. Why did the level of the earthquake largely exceed the design level?

3. How should the basic earthquake ground motion be defined to verify seismic safety of Kashiwazaki-Kariwa Nuclear Power Station in future?

4. Is seismic safety secured by the newly defined basic earthquake ground motion?



Summary of view points in analyzing the factor that the observation data exceeded the design value

• Summary of view points in factor analysis- Earthquake causes including tectonics, etc.

- Cause of pulse wave generation in building base ground

Factor analysis

Collection and summary of data on source fault / underground structure / ground motion

Review of the items to be reflected in the future seismic safety evaluation

Source Source characteristicscharacteristics

Soft rockSoft rock

Sand layer / Soil

Hard rockHard rock

Site amplification Site amplification characteristicscharacteristics

Propagation path Propagation path characteristicscharacteristics

GroundGround--building response building response characteristicscharacteristics

Outline of Analysis on the Earthquake and Ground Motion



• Impact of crack • exceed elastic region

Detailed investigation(analysis)

Verification of structural integrity against the earthquake

Important facility for seismic safety

Evaluation by test & inspection

Evaluation by analysis

Review on analysis model

Mutual consideration

•No impact of crack•Response is in elastic region

Detailed investigation (test & inspection)

Outline of Structural Integrity Evaluation on Reactor Building

Evaluation of impact on Reactor Building

Repair required or not



Basic policy of the integrity assessment as for facilities important to safety

Detailed study should be conducted through more detail analysis adding actual conditions or by implementing additional inspection

When the result of the analysis, using the analysis method applied at the designing stage and applying the observed earthquake ground motion, shows that the deformation of the facility exceeds the elastic range

Appropriate repair, replacement, etc. are necessary by conducting investigation and examination of the source of the damage

The integrity of the facility is judged to be maintained

When the result of the analysis, using the analysis method applied at the designing stage and applying the observed earthquake ground motion, shows that the deformation of the facility is within the elastic range

When, as a result of the inspection, damage is observed that affects the structure and/or function that is required by the technical standards

When, as a result of the inspection, any damage is not observed that affects the structure and function that is required by the technical standards

Analysis

Inspection



Current Status of Investigation



Evaluation of Seismic Ground Motions at the K-K NPP Site Area (By JNES)

(1) Earthquake source characteristics (asperities distribution) was determined by the Inversion analysis using observed ground motion distribution data of main shock and aftershocks.

(2) Geological structure (irregular and complex velocity structure) were identified using geological survey data.

(3) Fault model analysis (fault rupture process + seismic wave propagation) was carried out to generate seismic ground motion distribution.

(4) The analysis result revealed that the ground motion at the site areaamplified due to source characteristics, diffraction of seismic wave in irregularunderground structure (as a result, focusing at the Unit 1 side).

Source faultAsperity

Non-uniform soil structure

Site area

Focusing effect



KKNP

基盤岩

ｸﾞﾘｰﾝﾀﾌ・七谷下部寺泊

椎谷（Vs=0. 8～1. 7）

海域上部寺泊

（Vs=3.15）

（Vs=2.6）

（Vs=2.2）

（Vs=1.9）

西山（Vs=0. 7～1. 1）

W

Cross section of geological layers

Source region

Nishiyama

Shiiya Upper Teradomari

Green tuff/Nanatani

Lower Teradomari

Bedrock

Sea area

- The deep underground structure has irregularity, such as sharp dip zone beneath the site and anticline structure in north-east of the site.

- Earthquake bedrock near the site is deep as about 5~8 km, and sedimentary rock thickly cumulates on it.

Modelling of Source Fault and Ground Structure

E

Source fault model

Fault d

ip an

gle30

° ASP1ASP2

ASP3NPP site

Rupture initiation

0 sec

3.0sec

7.6sec

Strong seismic waves were generated by rupture of 3 asperities.

27kmS - E dip

(low angle) fault

N - W dip(high angle) weak fault



Summary of Factor Analysis

KK5 KK1KSH

Kashiwazaki 3Kashiwazaki 3--D underD under--ground structure modelground structure model

KK5 KK1KSH

Kashiwazaki stratified Kashiwazaki stratified soil layer modelsoil layer model

Thick sedimentThick sediment＋＋33--D irregularityD irregularityThick sediment Thick sediment

（（Deep bedrockDeep bedrock））

KK5 KK1KSH

Thin sediment Thin sediment （（Shallow bedrockShallow bedrock））

Sediment layer thickness

Standard Taisen Standard Taisen stratified soil layer modelstratified soil layer model

Irregular soil layer

Source characteristics

■ Generated ground motion is stronger・Short period level ～ 1.5 times・Directivity ～ 1.5 times

■ Amplification of ground motion at Unit 1 is large due to irregular thick soil layer.■ Effect of irregularity is small at Unit 5.

・Irregular soil layer at KK1 ～ 1.5 times

Source characteristics Irregularity of soil layer

■ Amplification of ground motion is large in thick stratified sediment layer

・Thickness of sediment layer ～1.5times

Thickness of sediment layerPredicted ground motion at KKI （3-

D difference Method） is about 5 times as large as Taisen spectrum.



Study on Simulation Model for Reactor Building Response



Observed＞Analysis at around 0.1～0.3 s

（Unit 1： Horizontal）

Observed： 2 peaksAnalysis： 1 peak at 0.3 s

（All units： Vertical）Point 1

（Unit 4： Horizontal）

Intermediate floor, NS

Intermediate floor, UD

Point 2 Point 3

Simulation model（1 axis lumped mass model）

Observed＜Analysis at around 0.09 s

On the Inconsistency between Analysis Results and Observation Records

Intermediate floor, NS

(TEPCO, 2007.12.25)（partially retouched）

1. Analyzed horizontal response spectrum of Unit 1 is smaller than the observed one at around 0.1–0.3 seconds.

2. Analysis cannot reproduce the tendency of twin peaks ataround 0.1 and 0.4 seconds, seen in the observation recordof Unit 4.

3. Analyzed vertical response spectrum has sharp peak at around 0.09 second, not seen in the observation records.

Res

pons

e ac

c.（

m/s

2 ）

(TEPCO, 2007.10.25) (partially retouched)‏

Observed

Analysis

Period (s)‏R

espo

nse

acc.

（m

/s2 ）

Period (s)‏

Res

pons

e ac

c.（

m/s

2 ）

Period (s)‏

Observed

Analysis Observed

Analysis



Results of Factor Analysis by ＪＮＥＳ

Seismometer location（2F）

Seismometer location（on basemat）

Building damping 3% Expansion

■ Soil-Building model■ Building model

（Input seismic wave observed at basemat）

Observation records were reproduced well by using 3-D FEM model, considering (1) influence of flexure of building floor and basemat, (2) interaction of embed-ded building side wall and soil, (3) constraint by existence of turbine building.

Turbine building

Basemat connects with soil

440

m133m

440m

（1号機）

0

1000

2000

3000

4000

0.01 0.1 1 10周期（秒）

加速

度応

答ス

ペク

トル (G

al)

観測(1号機地震計記録)

解析(1号機地震計付近)

0

1000

2000

3000

4000

0.01 0.1 1 10周期（秒）

加速

度応

答ス

ペク

トル (G

al)

観測(4号機地震計記録)

解析(4号機地震計付近)

0

1000

2000

3000

4000

0.01 0.1 1 10周　　期（秒）加

速度

応答

スペ

クトル

（Gal)

観測

解析

■ Analysis resultsUnit １： Horizontal （ＮＳ） Unit 4： Horizontal （ＮＳ） Unit 7： Vertical (UD)

Neighboring soil

水平

Building-soil interaction is taken into account

ObservedAnalysis Observed

Analysis

Observed

Analysis

Resp

onse

acc

. (G

al)

Period (s) ‏

Resp

onse

acc

. (G

al)

Period (s) ‏Re

spon

se a

cc. (

Gal

)Period (s) ‏



Integrity Evaluation of Facilities



Flow Chart of Facility Integrity Evaluation

Inspection Analysis

Basic inspection Seismic response analysis

Without abnormal

With abnormal Additional

inspection

Small seismic margin

Large seismic margin

Integrated evaluation of facility integrity



0

100

200

300

400

500

600

CRD housi

ng pe

netra

tion h

ole

Recircu

lation p

ump p

enetr

ation

hole

Feedwate

r Inje

ction

nozzl

e（Ｎ

６）

Pressur

e vess

el sta

bilize

r

CRD housi

ng re

strain

t bea

mReci

rculat

ion pump

ＲＰＶ

stabil

izer b

racke

t

Stre

ss（

ＭＰ

ａ）

：Evaluationpoint

Reactor coolant recirculation pump motor casing and evaluation point

・ Stress generated at recirculation pump motor casing (axial compression) became near the criterion value of component selection for inspection (= ＡＳ allowable stress limit).

Examples of Integrity Evaluation - Pressure Vessel -(JNES 2008.8.27,9.18)

Legend

Criterion for component selection byJNES

ＡＳ＊

Stress

Vertical load: V

Moment: M



0

100

200

300

400

500

600

Main

ste

am s

yste

m

Resi

dual

hea

t re

mova

l

Reac

tor

core

iso

lati

on c

ooli

ng

Fuel

poo

l co

olin

g wa

ter

clea

nup

Stre

ss（

ＭＰ

a）300

200

100

0

（Piping main part）（Piping support： snubber, restraint)

Snubber Restraint

Load

at s

nubb

er（

ｋＮ

）＊２：第１２回設備健全性評価サブＷＧ資料３「柏崎刈羽原子力発電所７号機設備強度評価結果」Ｐ１１

・ The stress at residual heat removal system piping is smaller than the AS allowable stress limit, but exceeds the criterion value of component selection for inspection.

・ The stress at residual heat removal system piping support (snubber) exceeds the evaluation criterion* (normal load×1.5).

＊ TEPCO, material presented at the 12th facility integrity evaluation sub-working group

Ex. of snubberEx. of restraint

Seismic design guideline for NPPJEAG4601-1991 P163

Residual heat removal Piping system

Subject piping support

Maximum stress point

Examples of Integrity Evaluation – Piping –(JNES 2008.8.27, 9.18)

Main

ste

am s

yste

m

Resi

dual

hea

t re

mova

l

Reac

tor

core

iso

lati

on c

ooli

ng

Fuel

poo

l co

olin

g wa

ter

clea

nup



Examples of Additional Inspection and Result

１．Confirmation of the integrity of pump motor casing at the whole circumference and at the inside of welding portions (Visual inspection by fiber scope)

→ Found no abnormality such as defect or deformation２．Study on inelastic strain based on the measurement of stiffness of

steel piping (reference data)→ Recognized increase in stiffness of deformed portion of

filtrate tank

３．Confirm the progress of cracks (which had been found to be 5mm in depth, 30mm in length) in recirculation piping connection by ultrasonic test, and observe microscopically stress corrosion cracking portion

→ Confirmed that there were no significant progress in cracks due to the earthquake loads

４．Investigation on the tendency of thinning in thickness of seismically important pipes, etc.



1. Evaluation of earthquake and ground motion(1) Necessity to consider strain concentration zone of the crust(1) Assumption of the earthquake scale equivalent to at least M6.8 for

isolated short active faults(2) Evaluation with consideration of uncertainty in source model

parameters, based on the geological survey, earthquake records and seismological findings, and clarification of evidence for setting up these parameters, etc.

2. Evaluation of geology and geological structure(1) Appropriate age identification of off-shore strata based on the index

such as fossil, etc.(2) Evaluation of continuation of active faults, based on the fact that faults

and folds are often disconnected or bent near the ground surface(3) Appropriate modeling of sediment layer, velocity structure, damping

characteristics, etc. of underground soil from seismic bedrock to base stratum, etc.

3. Evaluation of seismic safety of facilities(1) Evaluation by analysis model considering stiffness (flexibility) and

frequency characteristics of building and also check of the model by comparison with observed earthquake records

Main Items to be reflected in the Seismic Safety Evaluation of oher NPPs



--2 Re2 Re--evaluation of Existing NPPs evaluation of Existing NPPs by the Revised Seismic Reviewing Guide by the Revised Seismic Reviewing Guide

and KK Lessonsand KK Lessons



Evaluation of Seismic Safety of Existing Nuclear Facilities

(1) Instruction to the operator for the re-evaluation of seismic safety– In Sep. 2006, Nuclear and Industrial Safety Agency (NISA)

instructed the operator to re-evaluate the seismic safety of the existing nuclear facilities according to the revised Seismic Design Audit Guidelines

– After Niigata-ken Chuetsu-oki Earthquake in Jul. 2007, the Minister of METI instructed the operators to review the re-evaluation plans and submit interim reports by the end of Mar. 2008.

(2) Submission of interim report– By the end of Mar. 2008, all operators submitted interim reports.– NISA is reviewing the contents of the reports.– The operators will submit the final reports by Mar. 2010.



Flow of Seismic ReevaluationAccording to New Seismic Regulatory Guide

A. Geological survey, evaluation of active faults

Classification of im

portance

Items to be reflected to seism

ic safety reevaluationbased on the findings from

the Chuuetsu-oki E

arthquake

Evaluation of seismic safety of important

structures

Evaluation of important comp-onents and piping

Stability evaluation of basemat

Accompanying events(Stability of surrounding slop)

Accompanying events(Safety against Tsunami)

B. Evaluation of design basis ground motion SsGround motion without

identifying earthquake source

Evaluate ground motions

Ground motions by response spectra

Ground motions by fault model method

Exceedance prob.

Site specific ground motion by identifying earthquake source

ReferDefine design basis ground motion

C. Evaluation of seismic safety of facilities



Schedule of Seismic Safety Reevaluation2010

LWR(55 units)

FBR Monju

Rokkasho Reprocessing Facilities

2009200820072006Fiscal year

Geological survey

Seismic evaluation Provisional report Final report

Review for final reportReview （ＮＩＳＡ）

Review

Geological survey

Seismic evaluation

Review

Geological survey

Seismic evaluation

NISA and NSC review for K-7 completed （18 Feb.)

NISA request to revise evaluation plan based on NCO experience（Aug.’07）

K-7 Start-up after Prefectural Governor’s consent (8 May 2009)

Rev. of SRG (Sept. ’06)

Amendment of provi, repo.(Tsuruga, Mihama, Ohii,Takahama, Monjyu)

NISA review of K-6 safety evaluation result of facilities finished (24 June)

Kashiwazaki-city mayor's review for K-6 fire facilities finished (22 June)

NCO Earthquake(16 July)

NISA review of K-7 start-up test evaluation finished (24 June 2009)

NSC consent K-6 re-start (2 July)but TEPCO still need to get local governments’ consents



405600→700**C, Fo-A Fault (M6.9)→Fo-A+Fo-B（M7.4)Ooi370550Fo-A Fault (M6.9)Takahama456600Shinji Fault (M7.1)Shimane473570Central Tectonic Structure (M7.6)Ikata370500Earthquakes undefined specificallyGenkai

4502300 (#1 side)1209 (#5 side)

F-B Fault (M7.0), Nagaoka-plain-west Fault (M8.1)Kashiwazaki-Kariwa

372540Earthquakes undefined specificallySendai

405600→750**C, Fo-A Fault (M6.9)→B-Fault(M7.7)Mihama

532650→800**Urazoko-Uchiikemi Fault (M6.9), etc.→Mera-Kareizaki-Kaburagi F.(M7.8)

Tsuruga490600Sasanami-oki Fault (M7.6)Shika600800Assumed Tokai (M8.0), etc. Hamaoka380600Earthquakes undefined specificallyTokai370600Earthquake near the site (M7.1)Fukushima375450Earthquakes undefined specificallyHigashidoori375580Soutei Miyagiken-oki (M8.2)Onagawa

370 Gal550 GalEarthquakes undefined specificallyTomari

DBGM S2New DBGM Ss＊Contributing earthquakesPlant sites

New Design Basis Ground Motions

Note: * Black bold numbers are Ss by interim report (March 2008). ** Red bold numbers are corrected values by the amendment of interim report (31 March 2009 )

and still under examination in governmental committee (29 June 2009)‏



New Design Basis Ground MotionsTypical sample of Ss study in the amendment (March 2009) of the Interim Report by Utilities

Active faults considered in the Interim Report (March,2008) based on the Revised Guide

Portion modified after the Interim Report(March,2008)‏�

Faults in which simultaneous activity should be considered by NISA’s interim evaluation of activefaults

Tsuruga NPP site

A: Consideration of simultaneous activity of Mera-Kareizaki fault and Kaburagi fault (60km)

B: Consideration of simultaneous activity of Nosaka fault, B fault and outer-edge-of-the-continental-shelf fault (49km)

30km from the site

Mer

a-K

areiz

aki-o

ki fa

ult

Kaburagi faultOuter-ed

ge-of-

the-

contin

ental

-shelf

fault

B fault

Nosaka fault



Concluding Remarks・The Chuetsu-oki Earthquake gave significant impacts to the ‘ nuclear energy’

(not only NPPs but also the world of nuclear energy).

・Licensee, NISA, JNES, universities, national research laboratories, general constructions, plant makers have been directing all their energy to analyze this earthquake phenomena, evaluation of integrity of KK-NPPs, seismic reinforcement, etc.

・Through these investigations, wide range technologies supporting nuclear seismic safety have been progressed noticeably, and also the base has been formed to response to such an severe event in the regulation and to advance seismic safety and reliability of NPPs furthermore.

・Knowledge and findings obtained in these investigations are to;・be shared not only in our country but also internationally・be utilized to further advancement in nuclear seismic design or

evaluation guide.・For that, we are now collaborating to international seismic safety framework,

IAEA International Seismic Safety Centre and their activities.



Thank you for your attentionThank you for your attention