Regulatory Guide 1.60

Design Response Spectra for Seismic Design of Nuclear Power Plants

ML13350A358
Person / Time
Issue date:	10/31/1973
From:	US Atomic Energy Commission (AEC)
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RG-1.060
Download: ML13350A358 (6)

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\oU.S. ATOMIC ENERGY. COMMISSION:_.;:::

Ociober 1973

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DIRECTORATE OF REGULATO RY STANDARDS

WIDE

REGULATORY GUIDE 1.60

DESIGN RESPONSE.SPECTRA FOR SEISMIC.DESIGN

OF NUCLEAR POWER PLANTS

SA..

A. INTRODUCTION

.extensive study.'has hlcn described by Newmiaik and Blunie in re!ferences I. 2, .and After ieviewing th'se Criterion 2, "Design Bases for Protection Against reterenced documents, tilt AE( RegtIu10toiy 'staff has Natural Phenoniena," Of 'Appendix A, "General Design determined as acceptahle tile fI llowicni procedilre 1or'

Criteria for Nuclear.Power Plants." to 10 CFR Part 50. defining the Design RIeslponse Spectra representing the L'.'icensing of Production and Utilization Facilities." effects of the vibratory 111i00 Otf thi SS[, 1./2 the SS!.',

requires, in part, that nuclear power plant structures, and the Operating Basis Earthquake (0111) on sites syYStems, .,and components important to safety b'h underlain by either rock or sOil deIposits d:lCoVerfinig All designed to -withstand. the' effects of earthquakes. frequencies of inter.st. However, for uliustially soft site.

Proposed Appendix A, "Seistnic and Geologic Siting .modification to this procedure will.he requited.

Criteria,'"to :10 CFR Part .100, "Reactor Site Crinteria,i.

• Would require, in part, that the Safe Shutdown In this procedure,

• the .configurali6ios of tihe Earthquake (SSE) be defined by response spectra horizonial. component Design Response Spectra i'm each correspoanding 'to the expected maximum ground of the two: mutually perpendicular honizontal axes are

, acc:elerations..,This guide. describes a. piocedure shown in Figure 1. of this guide. These sh lpe% agree wilh

...acceptable: to the 'AEC ARegulatory staff- for defining

'th*se developed by', Newmnz'k, Blun

e. and Kapur in

1 kplants.

Sespqnsei spectra for the seismic design of nuclear power The Adviory Committee on Reactor Safeguards bas inconsulted been concurred the regulatoryconcerning position.this guide and has reference 1. In Figure 1 tihe ase diagram consists of three parts: the bottom. line:on he left part represents the maximum ground displacement, the bottom line on the right part represents, the maximum aceleration, and ithe middle part depends. on the maximum velocit

y. Thle

'

B. DISCUSSION

horizontal component Design Response Spectra in Figure I of tids guide correspond' to a 'maximuin in o.rder. to approximate the intensity and thereby horiznital ground acceleration of 1.0 g. "rlie maxintum estimate, the maximum :.gr6tund' acceleriationo Of the: ,ground displacement. is. uiken.'propportional to the

.expcted strongesýt..ground 'm'tion,(SsE) for a given site, maximum ground accekeration. and is'set.at 36 inches

pr.oposed -Append*- A,to I0.'.CFR- Part 100. specifies. a for'a.ground "acceleratioin of1.tI, 0 g."Thc nunierical values number of,'required investigations. It does not, however. of design displacements, velocities, and accelerations for giye a -method for 'defining.. the response spectral the horizont-al component Design Response Spectra are corresponding to 'tile expected nmaximunt. ground obtained by multiplying the corresponding values of the acceleration" maximum ground displacement and acceleraliol by the factors given in Table I of this guide. Tile displacenient The recorded ground acccleratioihs and response region lines of the Design Response Spectra ame parallel spectra of' past. earthquakes provide a, basis for the to the maximum ground displacement line and are rational design of structures to resist earthquakes. The shown. un lhie left of Figure I. The velocity region lines Design Response Spectra,' .specified for design purposes, sl.ope. downward from a. frequency nf 0.25" cps (control can be developed.statistically from.response spectra of. point D)'to a.frequency of 2.5 cps (control point C) and past strong-motion earthquakes (see' reference I).. An are shown at. the 'top. The remainting two sets' of" lines between the frequencies of 2.5 cps and 33 cps (control See definitions at the end of the guide. point A), with a break ata freqtuency cf 9 cps (control USAEC REGULATORY GUIDES Coplw of publithed guide. may be obtained by request indicating the dwvitant desired to the US. Atomic Energy Commistion. Washinglon. 0,C.. 7D545, ReguLatory Guides ae Issued to. descibe and make arvailable to the public Attention: Director of Regulatory Standards. Comments arml sugpltrinni lor methods aceptable w the AEC Regulatory tiaff of implemnenting specific parns of Imnorovenmerls in these guldot *re encouraged and should ae sent to the Secretary the Coammmion's regulations, to delineate techniques used by the staff in of the Comnmiuion, U.S.. Atomic Energy Commision, Washington. D.C. 20545.

vellualng specilic problenr'ofa.postulated accidents, or to provide guidance to Attention: Chief. Public Procetlings Staff.

liegplcanl. Regulatory Guldes are not tubslltuie' for regulations and compliance with them Is not required. Methods 'end. olutlont different'from those eat out in The guides are issued onshe following ten broad divisions:

the.gulde will be acceptable It they provide a basis for the findings requisite to the suamnce or omlnmlnuani of a permit or Ilcense by the Commission. 1. Pow" Reactors *

6. Producst

2. Research and Test Reactots *

7. Transpotation

.3. Fuels and Materials Facilitis .. 8' Occupational Health Pwwusdsd guides will be revised periodically, in appropriate. to aecommodate 4. Environmental and Siting " 9. Antitrust Review wornmntS ead to reflect new Inforn-llon or5,swrne. " . . Materials and Plant.Protection 1

0. General

F-

point W. constituit: tile acceleration region h ot' the earthquake or (2) have physical characteristics thfat horizontal I)csrgn Response Spectra. Fot frequencies could significanrtly afT'ct tile spectial pattern (f input Ihigher than 33 cps. the maximum ground acceleration motion, such as heing underlain by poor soil deposits.

line represents the Design Response Spectra. Ilte procedure described above will not apply. Irt these cases, ile D)esign Resixrse Spectra should be developed The vereial corrrponent I.sign Response Spectra iitdi\idua.ly acc*i ding to thie site characteristics.

.corrtesponlding to tile IllaxiuIIInIl hIri:minrlal ,rtlnd acceh'rafioi of I.0 g are slhown in Figure 2 ofih' is guid

C. REGULATORY POSITION

The nuneltici al vlues of design displacements. veloci ics.

and acceleratiotis inl these spetra are obtained by I . Tlie horizontal comtponrent ground 1elsign Response antrltiivying tile conrespol.Jing values of" the lrlaxitIniun Spectra. without soil-structn tre irtteractiorn effects, of the lihri:mital gr.u mIud moriott (acceleration = 1.0 g and SSIE, 112 the SSE, Otrthe OBE on sites underlain by rock displacemotw t = 3(N in.) hy the tactors given in Table II of or by soil should he linearly scaled from Figure 12 in lhi, guide. T"he displacentrertt reliunt lines of tlle Design propOrtiOrr to tire rnt:ixiruittn lt horizortmal ground Re-sponse Spectr;t :are parallel to the mnaxirritimum ground acceleration specilied for tIre ear thlquake closen. i Figure diisplacemtne line and are sMiomin on the left of Figure 2. I coitrespt;Ids to a tntaxinulti horimrilal ground velocity region lines slope downward f'rom a vhe acceler;tiont ofI 1.t) aind ,,ccomtlpanlyitig displacerternI of I'requency t' 0.25 cps (CIICtttil pohlt DI) to :1 fleqtuency 36 irt.l The applicable multiplicatiot fI'ctors ald corttrol oIf 3.5 cps (control point C) and are shown at the top. points are given ill Table I. For darmping ratios tot Titi reniahitnn twIO sets of lines bet weeni thie frequencies inchludd itt Fi.mrc I or Tible I. atline:tr interpolation of"3.5 cps and 3,3 cps Icontrol poini A). withI a break at should be used.

tile I'reqtlellcv ot Q cps (conitmll point 13). contllitute tIle accelera.li n tetioti o)f' tihe veefical Design Response 2. The vertical c nmttment ground Design Resporrse Spectra. It shliold be noted tltt tre vertical Design Spectta. without soil-stiructure interaction effects, of1 tite Response Spectra values are 2/3 tl.,)se of the horizontal SSE, 1/2 tite SSI.E, or the OWI" on sites underlain by rock Design Resp-nqte Spectra for frequencies less than 0.25: or hr soil should lie line:irlv scaled fronni Figure 22 ill I'm Ifrequencies higher tli:m 3.5. tiley are tIle s*me. wlhile proportion to tlt illraXilliLlin horizontal grouind the ratio varies between 2/3 arid I I'Mr frceuiencies acceletafion specified for tile earthlquake chosen. (Figure between 0.25 and 3.5. For frequencies higher thtan 33 " is based on a maxitimum /iri-'iial Sround acceleraiion cps. the Design Response Spectra ftollow tile rrraxirnrnl of 1.0 g and accomtpanying displacement of 3R in.) The giound :acceleration lirte. applicable muliiplication I'actors arnd control points are given ill Table II. For dalmping ratios riot incltded irt The horizontal antd vertical comnponent Design Figure 2 or Table II, a linear irierpolatiin shiould be Respomn:e Spectra irt Figures 1 and 2. respectively, of this used.

guide cirrespond to a tixitimuri horizontal ground acceleratiin of I 1.) e. FFr sites with different 2Tlhis does nor apply to sites which It) ar relalively clno taccelen*:tior% values specit'ied b'or the design earthquake.

to Ire epicenter ot an expecled eanrthquakc or (21 which have Ile Design Response Spectra should be linearly sacled physic.il characteristics thil could significantly affect tite Ifrom Fiigures I mrid 2 iti proportion to the specifled spectral riombinatioin o1" input molion. The D)esign Rcsponse tmaximtumn horizmontal ground acceleration. For sites that Spectra for such sites irould tie developed on a case-by-case

( I* are relat ivelv close to tile epicenter of :ai expected 1srsis.

I .0.-2

DEFINITIONS

Response Spectrum means a rlot f'l lite maxi1mum relationship obtained by analyzing, evaluating. and response (acceleration. velocity, or displacement) Of a statistically combining a number of individual icspi-mse family of idealized sinoe-degree.of.fiecdomn damped spectra derived from the records of siguificamit past oscillators as a function of natural irequencies (or eart hquakes.

periods) of the oscillators to a specified vibratory nmotion input a( their supports. When obtained from a Maximum (peak) Ground Acceleration specified for a recorded earthquake record, the response spectruin given sito means that value of the acceleiatioa which lends to be irregular. with a mlnihet of peaks and corecslx)nd-s to zero period in the design response spectra valleys. for that site. At zero period lie d&sign response sp-.clra acceleration is identical for all damping "alues and is equal to the maximum (peak) ground acceleration Design ,,soonse Spectrum is a relatively smototh specified for that site.

TABLE I

HORIZONTAL DESIGN RESPONSE SPECTRA

RELATIVE VALUES OF SPECTRUM AMPLIFICATION FACTORS

FOR CONTROL POINTS

SPercent Amplification Factors for Control Points of Acceleration' 2 Displacement'

Critical 2 Damping A(33 cls) B(9 cps) C(2.5 cps) D(0.25 cps)

0.5 1.0 4.96 5.95 3.20

2.0 1.0 3.54 4.25 2.50

5.0 1.0 2.61 3.13 2.05

7.0 1.0 2.27 2.72 I .88

10.0 1.0 1.90 2.28 1.70

'Maximum ,sound displacement is taken proportional to maximum ground acceleration, and is 36 in. for ground acceleration of 1.0 gravity.

2Acoeleration and displacement amplification factors are taken from recommendations given in reference I.

1.60-3

TA13LE II

VERTICAL DESIGN RESPONSE SPECTRA

RELATIVE VALUES OF SPECTRUM AMPLIFICATION FACTORS

FOR CONTROL POINTS

Percnt Ariplificaiion Factors for Control Points of Ac'*icra.On D spllccmnt 2 Criticr'l Dampring A(33 :n*) 8(9 cp) C(3.5 cps) D (0.2 5 c1 o.g I .A) 4,%o 5.95

.0 1.0 3.54 4.2. I.07

5.0 1.0 2.(11 3.13 1.37

7.0 I .0 2.27 2.72 I.25

10.0 1.0 I.90 2.2S

SMaximum ground displawcement ik* Ik.n proportional to na \imumn gpund acckleraion and is 36 in. fIor cround accelcration tit 1.0 gr.vity.

2 Accelera tion amplificalion lactots *or tilc I ical design rep'.nse slctra are equal 1o iho1c O'h f oS ril(ontia design reslidnwc pretra. %%hercdis displaceient amplification faitorq are 2/3 those *f" hori/tnral dcsign rekponc

rpccira. Thcsc~. ratiois belwccn tie arnplifiwation f'aciors ofl the t.o dcsicn rc.pons spectra are in agrceenln with those recommetnded in re.l'cretw I,

REFERENCES

1. Newmark, N. W.. John A. Blume. and Kanwar K. Spectra.*' Urbana. Illinois. USAEC Corntra.c No.

Kapur. "Design Responsc Spectra for Nuclear Power AT(4'?-5)-26o7. WASI.1 255. April 1073.

Plants," ASCE Structural Engineering Nleeting. San Francisco. April 19*73. 3, John A. Blume & Associates, "Recommendations for Shape of Earthquake Response Spectra," San

2. N. N1. Newmark Consulting Engineering Services. "A Francisco. California. USAEC Contract No.

Study of' Vertical and Horizontal Earthquake AT(49-5.)-301 1. WASH-1254. February 19.73.

a8

1.60-4

1000

500

200

100

>: U * /\ -,. *

S20- -

5 5

1110

0.1 0.2 0.5 1 2 5 10 20 50 100

FREQUENCY. cps a FIGURE I. HORIZONTAL DESIGN RESPONSE SPECTRA

GROUND ACCELERATION

-SCALED TO ig HORIZONTAL

1000

0.' 50 .5

100

CC

100

50

20

2i

• ',FREQUENC,L cps___

, .*/

GR UN AC EL RAIO

00

FIGURE 2. VERTICAL DESIGN RESPONSE SPECTRA-SCALED TO lg HORIZONTAL

GRCUND ACCELERATION