ML19331B205

Review of Seismic Design Criteria

ML19331B205
Person / Time
Site:	Midland
Issue date:	05/05/1970
From:	Kost G, Sharpe R JOHN A. BLUME & ASSOCIATES, ENGINEERS
To:
Shared Package
ML19331B203	List: ML19331B202 ML19331B205
References
NUDOCS 8007280794
Download: ML19331B205 (8)

Text

.

'.V p

.9 2-P S v 2 )m%--,

/

\\

_{l

'f t

i" '

'n 1.*

'%s.

f-

%;o

_G

.j r

REVIEW OF THE SEISMIC DESIGN CRITERIA FOR THE MIDLAND PLANT (Docket No. 50-329 and 50-330)

May 5, 1970

-~

JOHN A. BLUME & ASSOCIATES, ENGINEERS San Francisco, California 1383 i

so 7?'f ooon l

.. ~..

... ~.

a-a._...

.. - -. -.. -.. =.

m g

REVIEW OF THE SElSMIC DESIGN CRITERI A FOR THE MIDLAND PLANT e

~

m (Docket No. 50'-329 and 50-330)-

This report summarizes our review of the engineering factors pertinent to the seismic and ' structural adequacy of the Midland PI' ant.

The plant is located along the south shore of the Tittabawassee River adjacent to the Dow Chemical Company's main complex in Midland, Michigan.

The design and construction of the plant will be performed by Bechtel Corporation unde'r direction of the applicant, Consumers Power Company. The nuclear steam supply system will be supplied by the Babcock & Wilcox Company. The plant will be composed of two units having a combined capability of 1,300 MWe and 4,050,000 lb/hr of process steam. The process. steam will be sup-plied to the Dow Ch?mical Company and the electricity to the applicant.

Application for a construction permit has been made to the U. S. Atomic Energy Commission (AEC Docket Nos. 50-329 and 50-330) by Consumers Power Company. A Safety Analysis Report has been submitted in support of'the application to show that the plant will be designed and constructed in a manner which will provide for safe and reliable operation.

Our review is based upon the information presented in the Safety Analysis Report and is directed specifically towards an evaluation of the seismic and structur-al design criteria for Class I structures, systems, and components. The list of reference documents upon which this review has been based is given at t.se end of this report.

DESCRIPTION OF THE FACILITY The Midland Plant site is located on a level plain formed by glacial lake deposits.

Elevations vary from about 600 f t to 625 ft above mean sea lev-el.

Drainage is to the northeast into the Tittabawasse River. The river flows to the southeast and coincides with the northeast boundary of the 1

t JCHN A. E! UME & ASSCO;ATO. CNGINCZ":S I

m site. The uppermost soil in the area is quartz sand which is locally clay-ey and varies' from 0 to 40 ft in thickness. - Below this sand is a layer of blue gray clay which in turn is underlain by sands and gravels to a total

5 depth of about 350 ft.

These unconsolidated Pleistocene glacial lake de-posits rest unconformably upon well consolidated sediments of Pennsylvania age. The reactor and auxiliary buildings will be supported on mat founda-tions on' the clay layers underlying the uppermost sand. This material var-le's from stiff ta hard and should provide adequate support. Other major

. structures will be founded partly or entirely upon compacted fill.

The containment structure will be a prestressed concrete cylinder and dome

~

. hich wIll be supported on _ a reinforced concrete foundation slab. The in-w terior of the structure will be lined with a 1/4-inch thick welded steel plate to ensure leak tightness. The inside diameter of the containment structure will be 116 f t and the -inside height including the dome will be 193 ft.

The vertical wall thickness will be 3-1/2 ft and the dome thick-ness will be 3.ft.

Tne foundation slab thickness will be 9 ft.

The dome and walls of the containment structure will be post-tensioned. This post--

tensioning system will consist of three groups of dome tendons oriented at 120 to each other and anchored at the vertical face of the dome ring

~-

girder; the walls are to be post-tensioned by vertical tendons anchored at the' top surface of ring girder and at the bottom of the base slab.

in addition, three groups of hoop tendons enclosing 240 of arc will be anchored at three vertical buttresses.

STRUCTURAL DESIGN CRITERI A AND LOADS j

All structures, equipment, systems, and piping are classified according to function or consequence of failure as either Class 1 or 2 as defined i

in Appendix SA of the Safety Analysis Report.

Class I structures, sys-f tems, and equipment are those whose failure could cause uncontrolled re-lease of radioactivity or are those essential for immediate and long-term operation following a loss-of-coolant accident. They are designed

, JOHN A. SLUME & ASSCCIATES. INCINEERS

m to withstand the appropriate seismic loads simultaneously with other applicable loads without loss of function.

Class 2 structures, sys-tems, and equipment are those whose failure would not result in a 1

release of radioactivity and would not prevent reactor shutdown but 3

may Interrupt power generation.

The design loads for the Midland Plant are divided into two basic cate-gories. The firs.t category includes normal operation,(dead, live, and prestress loads) and the second category includes accident, seismic and tornado conditions.

Structure design loads will be increased by load factors based on the probability and conservatism of the predicted design loads. Yield capacity reduction factors will be applied to the stresses allowed by the appilcable building codes.

ADEQUACY OF THE SEISMIC DESIGN CRITERIA We have reviewed the Preliminary Safety Analysis Report and Amendments No. I through 10 and have discussed the various aspects of the seismic design of the plant with the applicant and members of the staff of the Division of Reactor Licensing at meetings on January 29, 1970, and March 19, 1970. We have the following comments regarding the adequacy of the seismic design criteria:

1.

The data submitted by the applicant has included detailed discus-sions and analyses of allowable bearing pressures, settlements in founding materials, and the possibility of IIquefaction.

2.

According to data submitted by the applicant, there is no known l

i faulting near the site. The nearest faulting is about 55 miles south of the site consisting of a questionable fault zone which orobably trends northwesterly.

Other faults are known which are situated 325 miles northwest and 240 miles northwest of the site.

The low dipping basement rocks contain gentle folds but are other-wise relatively undisturbed. The condition of the Paleezoic base-

[

ment rocks indicates that the region has not been subjected to significant tectonic activity since at least the Paleozoic Era.

l !

JOHN A. ELUME & ASSOC;ATES. INCINEERS

.l- -.

^T^

=

N r

~

3 Midland, Michigan is in a se;smically quiet area.

Five earthquakes

~

are known to have been centered within 150 miles of the site, and none of these were felt strongly at Midland. There is no known e

geologic control of earthquake occurrence or distribution in the region. The greatest ~ historic shock' felt at Midland is estimated to have had a' MM Intensity V or an equivalent acceleration of.

about 0.03g. A value of 0.06g maximum ground acceleration-is postulated for the " Design" Earthquake.and 0.129 is postulated for the " Maximum" Earthquake. We concur with the selection of.these ground accelerations. The site response spectra for the Design.

and Maximum Earthquakes and the appilcation of these ::Ite spectra, including provisions for safety margins, as proposed by the appil-cant in Amendment 19, pages 9.00-3 and 900-4 are satisfactory and if properly implemented will result in a conservative design.

4.

The applicant has stated that he will use the response spectrum method of dynamic analysis for Cle.ss I strue.tures, piping, and equipment. The structures wi11 be analysed for. response in both the horizontal and vertical directions, and a range of foundation material moduli will be used in the analyses to account for varia-

.tions in these modull. Time-history analyses of Class I struc-tures will be performed to develop response spectra in vertical and horizontal directions at the points of support of piping and equipment.

The applicant has proposed to analyse some piping systems for a

~

static load equal to the peak of the response spectrum curve at points of support of the system in lieu of performing a dynamic l

analysis. This method will be used only when twice the resulting seismic stresses in combination with other applicable stresses are below the code allowable stress. The applicant has presented representative comparisons of the results of analyses utilizing the proposed static loading approach and the results of dynamic analyses of the same systems which demonstrate the conservatism of the proposed approach.

- JOHN A. SLLME & ASSOC; MIS. IN INIIP3

,?

N

~

We concur in general with the proposed approach to the seismic design of Class I structures, piping, and equipment. The analy-tical techniques. proposed by the appilcant are satisfactory and

~

if properly implemented will result in a conservative design.

CONCLUSIONS On the basis of the information presented by 'the applicant in the Pre-liminary Safety Analysis Report and Amendments, it is our opinion that the seismic design criteria and approach to seismic design as outlined

~

In the PSAR and Amendments 1 through 10,If properly implemented by the applicant, will result in a design that is adequate to resist the earthquake conditions postulated for the site.

JOHN A. BLUME & ASSOCIATES, ENGINEERS b

Ld-s 4/t Roland L. Sharpe

[fff 3

~

Garrison Kost ma-9 Q

.JCHN A. SLUME & ASSOCIA725. INCNZUS

.,f._..

'N

". r.

(

'e 5

REFERENCES t

MIDLAND PLANT CONSUMERS POWER COMPANY J

Preliminary Safety Analysis Report, Volumes I 11, and ill Amendments 1 through 10

" Midland Nuclear Site Consideracions" I

j 1

. JOHN A. SLtJMg & ASSCC;ATrs. ENG.Nggqs

y

~

M '"' gohn AO Blume & Associate 3

^ '

C""'"'

^' ' " 'C ' V '"

~, ~.

6an Francisco, California 4105 5-6-70 5-8-707

/4g

{g LTR.

MEMOS I

iRT:

CTH ER:

1 Os ORIO.s CC:

CTH ER:

s_

1 ACTION NECESSARY O

CONCURRENCE O

o^TE AnswERr-O COMMENT O

avi NO ACTION NECESSARY CL.ALSI Ps POST OFFICE FILE CODES

. p/

U 50-327 50-330 6,,c 4 r/ % M REo. no, CE;C%3PTION: (Mutt Be Uric.lassified)

REFERRED TO DATE RECEIVED BY DATE Ltr furnishing cocecrts on P.VR, Vol's g, p g

yg I,II,III & Ardts 1 t.hru 10 for the v A evs foi action Midinni Plant & trans:

DIRIPl WIION:

""C'****'

,, Review of the Sciar1c ge-d y Regulatory file cp until Orig returned (Ltr only R port -

g g p gg 7 qag Design for the Midland Plant., dtd H. Price & Staff 5-5-70.

gm.,4e/schioeae,-

ard '

JU AU RMUR TinYmme (5 cys rec'd)

P. Howe t w c/ w r,.,.,

Muller /Bluit(W/ orig & 3 cys...oris to be REMARKat

" t Tr~' t0 016 f?> fill:G)

No. Original signed cy of Report cec' 1 lYs &.

bt,dl$/Mh "i

"~~

A'

/

/

u.S. ATOMIC ENERGY COMMISGION MAIL CONTROL FORM FORM AEC-326S

<e co) o o....... m T...,...m. o.....

6 4

1 l

.__