ML20052C044

From kanterella
Revision as of 21:12, 9 March 2020 by StriderTol (talk | contribs) (StriderTol Bot insert)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search
Plant Unique Analysis Rept,Vol 3,Vent Sys Analysis.
ML20052C044
Person / Time
Site: Fermi DTE Energy icon.png
Issue date: 04/30/1982
From: Edwards N, Higginbotham A, Lehnert R
NUTECH ENGINEERS, INC.
To:
Shared Package
ML20052C024 List:
References
DET-04-028-3, DET-4-28-3, NUDOCS 8205040296
Download: ML20052C044 (248)


Text

,. . _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _. _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . ..

O DET-04-028-3 Revision 0 April 1982 ENRICO FERMI ATOMIC POWER PLANT UNIT 2 PLANT UNIQUE ANALYSIS REPORT VOLUME 3 VENT SYSTEM ANALYSIS Prepared for:

Detroit Edison Company Prepared by:

NUTECH Engineers, Inc.

Prepared by: Reviewed by:

(- W R. A. Lehnert, P.E. T. J Wenner, P.E.

Engineering Manager Engineering Director Approved by: Issued by:

Dr. A. B. ginbotham, .E. R. H. Kohrs, P.E.

General M ger Project Director Engineerin Departmen

, ((}/ LLL -

Dr. N. W. Edwards, P.E. d. H . Buchholz Senior Vice-President Project General Manager nuttg'h 8 2 0 5 0 4 Dac1 (> ,

REVISION CONTROL SHEET REPORT N"MBER: DET--0 4 -02 8-3 TITLE: ENRICO FERMI ATOMIC POWER PLANT, UNIT 2 Revision 0 PLANT UNIQUE ANALYSIS REPORT VOLUME 3 i

_ k hsup 1C1 4 J. C. Attwood / Senior Consultant Initial

%f/ / Eng. Analyst M /.Fitzge'r'ald w M. L. Initial Ww L VA V. KtImar / Project Engineer Initial Y _ k b l-.

A. S. Lee / Specialist Initial

{t , VKR l-.

V. K. Lee / Consultant I Initial b

R. A. Lehnert / Eng. Manager Initial L

T. Lem / Specialist Initial K. Loo / Specialist Initial

. . A J. D. Lowe / Eng. Analyst Initial SFl S. Mofid / Specialist Initial nute_q=h

3-ii

l l

l REVISION CONTROL SHEET (ContinuationJ TITLE: ENRICO FERMI ATOMIC REPORT NUMBER: DET-04-028-3 POWER PLANT, UNIT 2 Revision 0 PLANT UNIQUE ANALYSIS REPORT VOLUME 3 4tt t242 W K. E. Parzyck / Erfof. Analyst Initial

&_ u R. D. Quinn / Consultant I Initial Ann ( nu w)

S. P. Quinn / Senior T3chnician Initial' o S. H.

~ LL/ Consultant I

/Rosenblum MK Initial

/ /m /

M.'A. Ruher's Specialist Ibiti'al

& ), Olu., c bzW &Y3 W. E. Smith / Associate Engineer Initial .

"b ,

S. S. Tang / S ior Engineer Inipal 0 nh $ Oswuabc cs7 C. S. Tefamoto / Consultant I Initial

[@t~- #"

A c4)

Y. C. Yp / Er[gineer Initial '

l ...

3-111 nutggh

REVISION CONTROL SHEET (Continuation)

TITLE: ENRICO FERMI ATOMIC REPORT EUMBER: DET-04-028-3

[] POWER PLANT, UNIT 2 Revision 0 V PLANT UNIQUE ANALYSIS REPORT VOLUME 3 REV PRE- ACCURACY CRITERIA E REV PRE- ACCURACY CRITERIA E

PARED CHECK CtIECK PARED CHECK CHECK PAGE(S) PAGE(S) 3-vi 0 gyL VK V(, 3-2.68 0 KEP M VK 3-vii g y 3-2.69 3-viii through [Lpt, Vk R 9d2 3-2.72 through g g(tp vg 3-1x 3-2.73 3-x through @ VK gftp through 3-xv g 1/4  % 3-2.74 3-2.75 3-1.1 through XEP KLO vK through 4 g9ef \/R, 3-2.76 3-1.7 3-2.77 (IGF KLO VK 3-2.1 g/PL, VK. V k. 3-2.78 /W KLO vg, O'

3-2.2 3-2.79 bF, through 3-2,10

[2/tt. g VK through 3-2.84 M V k.

3-2.11 3-2.85 / 97 KLO VK 3-2.86 S OI Vg 3-2.25 3-2.87

$ IV  %

throu @ NN 3-2.88 Q y( V4 3-2.89 3-2.56 through ff{t, gpq y through gat VK R#d2 3-2.97 3-2.57

~

3-2.58 HLP SH kTL - 3-2.99 3-2.59 through g4 RMQ yg through 3-2.62 66,I @ Q 3-2.101 3-2.102 3-2.63 through filf KL.O VK through 3-2.104 88$ (% VK l

3-2.64 3-2.105 t u g

[N I

p V

3-2.66 U

3-2.67 M t1CF VK QEP-001.4-00 3-1v nutech ==

REVISION CONTROL SHEET (Continuation)

(

TITLE: ENRICO FERMI ATOMIC REPORT NUMBER: DET-04-028-3 POWER PLANT, UNIT 2 Revision 0 O PLANT UNIQUE ANALYSIS REPORT VOLUME 3 ACCURACY CRITERIA PRE- ACCURACY CRITERIA E REV PRE- E REV PARED CHECK CHECK PARED CHECK CHECK PAGE (S)

PAGE (S) 3-2.109 0 3-2.172 0 fig 44 W gug Rva vk @* 3-2.173 ru cur gav 3-2.112 3-2.174 ddAt Sd NAE through %AL,,. RN Vk 3-2,175 KEP /hP 4N

~

3-2.176 ASL V'KRL (>7 dfff V IC., 3-2.177 #s< $.H EPd2 tr rMF 3-2.136 3-2.178 M 8- M J"b 3-2.137 through b gy gpg 3-2.179 through S C >T hTL-3-2.143 3-2.181 3-2,144 3-2.182 through  % R 8Q V k. through hb NN 8 3-2.148 3-2.186 3-2.149 ggp 6 >f R#d2 3-3.1 $ VK $4 3-2.150 through g gpg V k.

3-2.158 3-2.159 Q ($rT AM 3-2.160 dDL gL.

3-2.161 through KEP c9T R#4 3-2.162 3-2.163 7% d'56 3-2.164 through 4 gSkQ \/K 3-2,167 3-2.168 g gpp yg 3-2.169 through 3-2.170 g gpg yK 3-2.171 y rfy of V R, 0

A QEP-001.4-00 3-v nutggh  !

e ABSTRACT

\

The primary containment for the Enrico Fermi Atomic Power Plant, Unit 2, was designed, erected, pressure-tested, and ASME Code N-stamped during the early 1970 's for the Detroit Edison Company by the Chicago Bridge and Iron Company. Since that time new requirements, defined in the Nuclear Regulatory Commission's Safety Evaluation Report NUREG-0661, which affect the design and operation of the primary containment system have evolved. The requirements to be addressed include an assessment of additional containment design loads postulated to occur during a loss-of-coolant accident or a safety relief valve discharge event, as well as an assessment of the ef fects that these postu-lated events have on the operational characteristics of the con-tainment system.

This plant unique analysis report documents the efforts under-taken to address and resolve each of the applicable NUREG-0661 '

d requirements, and demonstrates, in accordance with NUREG-0661 acceptance criteria, that the design of the primary containment system is adequate and that original design safety margins have been restored. The report is composed of five volumes which are:

o Volume 1 -

GENERAL CRITERIA AND LOADS METHODOLOGY o Volume 2 -

SUPPRESSION CHAMBER ANALYSIS o Volume 3 -

VENT SYSTEM ANALYSIS o Volume 4 -

INTERNAL STRUCTURES ANALYSIS o Volume 5 -

SAFETY RELIEF VALVE PIPING ANALYSIS This volume, Volume 3, which documents the evaluation of the vent system, has been prepared by NUTECH Engineers, Incorporated (NUTECH), acting as an agent responsible to the Detroit Edison Company.

()

O DET-04-028-3 Revision 0 3-vi nutagh

TABLE OF CONTENTS g Page ABSTRACT 3-vi LIST OF ACRONYMS 3-viii LIST OF TABLES 3-x LIST OF FIGURES 3-xiii 3-

1.0 INTRODUCTION

3-1.]

3-1.1 Scope of Ana ysis 3-1. 3 3-1.2 Summary and Conclusions 3-1.5 3-2.0 VENT SYSTEM ANALYSIS 3-2 .1 3-2.1 Component Description 3-2.2 3-2.2 Loads and Load Combinations 3-2.25 3-2.2.1 Loads 3-2.26 3-2.2.2 Load Combinations 3-2.89 lll 3-2.3 Analysis Acceptance Criteria 3-2.105 3-2.4 Method of Analysis 3-2.112 3-2.4.1 Analysis for Major Loads 3-2.113 3-2.4.2 Analysis for Asymmetric 3-2.144 Loads 3-2. 4. 3 Analysis for Local Ef fects 3-2.150 3-2.4.4 Methods for Evaluating 3-2.164 Analysis Results 3-2.5 Analysis Results 3-2.169 3-2.5.1 Discussion of Analysis 3-2.182 Results 3-2. 5. 2 Closure 3-2.185 3-3.0 LIST OF REFERENCES 3-3.1 DET-04-028-3 Revision 0 3-vil nutggh

LIST OF ACRONYMS

.r G)

ADS Automatic Depressurization System ACI American Concrete Institute AISC American Institute of Steel Construction ASME American Society of Mechanical Engineers CDP Cumulative Distribution Function CO Condensation Oscillation DC Downcomer DC/VH Downcomer/ Vent Header DBA Design Basis Accident DBE Design Basis Earthquake DLF Dynamic Load Factor FSAR Final Safety Analysis Report

^

(3x/ FSI Fluid-Structure Interaction FSTF Full-Scale Test Facility IBA Intermediate Break Accident LDR Load Definition Report LOCA Loss-of-Coolant Accident MC Midcylinder MJ Mitered Joint MVA Multiple Valve Actuation NEP Non-Exceedance Probability NOC Normal Operating Conditions NRC Nuclear Regulatory Commission I^' DET-04-028-3 Revision 0 3-viii nut.ech

LIST OF ACRONYMS (Concluded) g NVB Non-Vent Line Bay NWL Normal Water Level OBE Operating Basis Earthquake PSD Power Spectral Density PUA Plant Unique Analysis PUAAG Plant Unique Analysis Application Guide PUAR Plant Unique Analysis Report PULD Plant Unique Load Definition QSTP Quarter-Scale Test Facility RPV Reactor Pressure Vessel RSEL Resultant-Static-Equivalent Load SBA Small Break Accident SER Safety Evaluation Report SRSS Square Root of the Sum of the Squares SRV Safety Relief Valve SRVDL Safety Relief Valve Discharge Line SSE Safe Shutdown Earthquake SVA Single Valve Actuation TAP Torus-Attached Piping l VB Vent Line Bay VH Vent Header VL Vent Line VL/VH Vent Line/ Vent Header DET-04-028-3 Revision 0 3-ix nutggh

LIST OF TABLES 7._

\-

Number Title Page 3-2.2-1 Vent System Component Loading 3-2.56 Information 3-2.2-2 Suppression Pool Temperature Response 3-2.57 Analysis Results - Maximum Temperatures 3-2.2-3 Vent System Pressurization and Thrust 3-2.58 Loads for DBA Event 3-2.2-4 Pool Swell Impact Loads for Vent Line 3-2.59 3-2.2-5 Pool Swell Impact Loads for Other 3-2.60 Vent System Components 3-2.2-6 Vent System Froth Impingement and 3-2.61 Fallback Loads 3-2.2-7 Vent System Pool Fallback Loads 3-2.62 3-2.2-8 Downcomer LOCA Air Clearing Submerged 3-2.63 Structure Load Distribution

() 3-2.2-9 Support Column LOCA Air Clearing Submerged Structure Load 3-2.64 Distribution 3-2.2-10 IBA Condensation Oscillation 3-2.65 Downcomer Loads 3-2.2-11 DBA Condensation Oscillation 3-2.66 Downcomer Loads 3-2.2-12 IBA and DBA Condensation Oscillation 3-2.67 Vent System Internal Pressures 3-2.2-13 Support Column DBA Condensation 3-2.68 Oscillation Submerged Structure Load Distribution 3-2.2-14 Maximum Downcomer Chugging Load 3-2.69 Magnitude Determination 3-2.2-15 Multiple Downcomer Chugging Load 3-2.70 Magnitude Determination O)

(, DET-04-028-3 3-x Revision 0 nutggh

LIST OF TABLES (Continued)

Number Title Page O 3-2.2-16 Chugging Lateral Loads for Multiple 3-2.71 Downcomers - Maximum Overall Effects 3-2.2-17 Chugging Lateral Loads for Two 3-2.72 Downcomers Loaded - Maximize Local Effects 3-2.2-18 Load Reversal Histogram for Chugging 3-2.73 Downcomer Lateral Load Fatigue Evaluation 3-2.2-19 Chugging Vent System Internal 3-2.74 Pressures 3-2.2-20 Support Column Pre-Chug Submerged 3-2.75 Structure Load Distribution 3-2.2-21 Support Column Post-Chug Submerged 3-2.76 Structure Load Distribution 3-2.2-22 Downcomer SRV Discharge Submerged 3-2.77 Structure Load Distribution 3-2.2-23 Support Column SRV Submerged Structure 3-2.78 h Load Distribution 3-2,2-24 Mark I Containment Event Combinations 3-2.98 3-2.2-25 Controlling Vent System Load 3-2.99 Combinations l 3-2.2-26 Enveloping Logic for Controlling 3-2.101 i Vent System Load Combinations 3-2.3-1 Allowable Stresses for Vent System 3-2.109 Components and Component Supports 1

3-2.3-2 Allowable Displacements and Cycles 3-2.111 for Vent Line Bellows I

! 3-2.4-1 Vent System Frequency Analysis 3-2.133 l

Results with Water Inside Downcomers I

l 3-2.4-2 Vent System Frequency A.alysis 1-2.134  ;

Results without Water Inside l Downcomers DET-04-028-3 llh l Revision 0 3-xi nutgch

i I'

l r

LIST OF TABLES

(); (Concluded)

Title Page Number 3-2.5-1 Major Vent System Component Maximum 3-2.171 Membrane Stresses for Governing Loads 3-2.5-2 Maximum Column Reactions for 3-2.172 Governing Vent System Loads 3-2. 5- 3 Maximum Vent Line - Drywell 3-2.173 Penetration Reactions for Governing Vent System Loads 3-2.5-4 Maximum Vent Line Bellows 3-2.174 Displacements for Governing Vent System Loads 3-2.5-5 Maximum Vent System Stresses 3-2.175 for Controlling Load Combinations 3- 2. 5- 6 Maximum Vent Line - SRV Piping 3-2.176 Penetration Stresses for Controlling Load Combinations 3-2.5-7 Maximum Vent Line Bellows 3-2.177 q(/ Differential Displacements for Controlling Load Combinations 3-2.5-8 Maximum Fatigue Usage Factors 3-2.178 for Vent System Components and Welds 1

DET-04-028-3

(]) Revision 0 3-xii nutggb

LIST OF FIGURES Number Title Page, O

3-2.1-1 Plan View of Containment 3-2.11

, 3-2.1-2 Elevation View of Containment 3-2.12 3-2.1-3 Suppression Chamber Section - 3-2.13 Midcylinder Vent Line Bay 3-2.1-4 Suppression Chamber Section - 3-2.14 Mitered Joint 3-2.1-5 Suppression Chamber Section - 3-2.15 Midcylinder Non-Vent Line Bay 3-2.1-6 Developed View of Suppression 3-2.16 Chamber Segment 3-2.1-7 Vent Line Details - Upper End 3-2.17 3-2.1-8 Vent Line Details - Lower End 3-2.18 3-2.1-9 Vent Line-SRV Piping Penetration 3-2.19 Nozzle Details 3-2.1-10 Vent Line - Vent Header 3-2.20 Intersection Details 3-2.1-11 Developed View of Vent Header 3-2.21 and Downcomer Bracing System 3-2.1-12 Downcomer - Vent Header 3-2.22 Intersection Details 3-2.1-13 Support Column Ring Plate Details 3-2.23 3-2.1-14 Support Column Details 3-2.24 3-2.2-1 Vent System Internal Pressures 3-2.79 for SBA Event 3-2. 2-2 Vent System Internal Pressures 3-2.80 for IBA Event 3-2.2-3 Vent System Internal Pressures 3-2.81 for DBA Event 3- 2. 2-4 Vent System Temperatures for 3-2.82 SBA Event llh DET-04-028-3 Revision 0 3-xiii nutggh

LIST OF FIGURES

, (Continued)

Number Title Page 3-2.2-5 Vent System Temperatures for IBA 3-2.83 Event 3-2.2-6 Vent System Temperatures for DBA 3-2.84 Event 3-2.2-7 Downcomer Pool Swell Impact Loads 3-2.85 3-2.2-8 Pool Swell Impact Loads for Vent 3-2.66 Header Deflectors at Selected Locations 3-2.2-9 IBA and DBA Condensation 3-2.87 Oscillation Downcomer Differential Pressure Load Distribution 3-2.2-10 Pool Acceleration Profile for 3-2.88 Dominant Suppression Chamber Frequency at Midcylinder Location 3-2.2-11 Vent System SBA Event Sequence 3-2.102

() 3-2.2-12 Vent System IBA Event Sequence 3-2.103 3-2.2-13 Vent System DBA Event Sequence 3-2.104 3-2.4-1 Vent System 1/16th Segment Beam 3-2.137 Model - Isometric View 3-2.4-2 Harmonic Analysis Results for 3-2.138 Downcomer Submerged Structure Load Frequency Determination 3-2.4-3 Harmonic Analysis Results for 3-2.139 Support Column Submerged Structure Load Frequency Determination 3-2.4-4 Harmonic Analysis Results for 3-2.140 Condensation oscillation Downcomer Load Frequency Determination 3-2.4-5 Harmonic Analysis Results for 3-2.141 Condensation Oscillation Vent System Pressure Load Frequency Determination b'N- DET-04-028-3 Revision 0 3-xiv

LIST OF FIGURES (Concluded)

Number Title Page__

3-2.4-6 Harmonic Analysis Results for 3-2.142 Chugging Downcomer Lateral Load Frequency Determination 3-2.4-7 Harmonic Analysis Results for 3-2.143 Chugging Vent System Pressure Load Frequency Determination 3-2.4-8 Vent System 180' Beam Model - 3-2.149 Isometric View 3-2.4-9 Vent Line Drywell Penetration 3-2.159 Axisymmetric Finite Difference Model - View of Typical Meridian 3-2.4-10 SRV Piping - Vent Line Penetration 3-2.160 Finite Element Model - Isometric View 3-2.4-11 Vent Line-Vent Header Intersection 3-2.161 Finite Element Model - Isometric View 3-2.4-12 Downcomer-Vent Header Intersection 3-2.162 Finite Element Model - Isometric View 3-2.4-13 SRV Piping - Vent Line Penetration 3-2.163 Axisymmetric Finite Element Model for Local Thermal Analysis - View of Typical Meridian 3-2.4-14 Allowable Number of Stress Cycles 3-2.168 for Vent System Fatigue Evaluation 3-2.5-1 Vent System Support Column Response 3-2.179 Due to Pool Swell Impact Loads -

Outside Column 3-2.5-2 Vent System Support Column Response 3-2.180 Due to Pool Swell Impact Loads -

Inside Column 3-2.5-3 Vacuum Breaker Response Due to Pool 3-2.181 Swell Impact Loads DET-04-028-3 Revision 0 3- xv lll nutggh

3-

1.0 INTRODUCTION

In conjunction with Volume 1 of the Plant Unique Analysis Report (PUAR), this volume documents the ef-forts undertaken to address the requirements defined in NUREG-0661 which affect the Fermi 2 vent system. The vent system PUAR is organized as follows:

o INFRODUCTION Scope of Analysis Summary and Conclusions o VENT SYSTEM ANALYSIS Component Description O -

toeae ead toed Combineetons Analysis Acceptance criteria Method of Analysis ,

Analysis Results The INTRODUCTION section contains an overview discussion of the scope of the vent system evaluation, as-well as a summary of the conclusions derived from the comprehen-sive evaluation of the vent system. The VENT SYSTEM i

ANALYSIS section contains a comprehensive discussion of ,

! i the vent system loads and load combinations, and a description of the component parts of the vent system DET-04-028-3 Revision 0 3-1.1

affected by these loads. The section also contains a discussion of the methodology used to evaluate the effects of these loads, the associated evaluation results, and the acceptance limits to which the results are compared.

9 l

DET-04-028-3 Revision 0 3-1.2 nutggb

3-1.1 Scope of Analysis The criteria presented in Volume 1 are used as the basis for the Fermi 2 vent system evaluation. The modified vent system is evaluated for the ef fects of LOCA related loads and SRV discharge related loads defined by the NRC Safety Evaluation Report NUREG-0661 (Reference 1) and the Mark I Containment Program Load Definition Report (LDR) (Reference 2).

The LOCA and SRV discharge loads used in this evaluation are formulated using the methodology discussed in Volume 1 of this report. The loads are developed using the O ete"e ""is=e se eerv- ver ei=9 e r eeer - #a ee e results contained in the Plant Unique Load Definition (PULD) report (Reference 3). The effects of increased suppression pool temperatures which occur during SRV discharge events are also evaluated. These temperatures are taken from the plant's suppression pool temperature response analysis. Other loads and methodology, such as the evaluation for seismic loads, are taken from the plant's Final Safety Analysis Report (FSAR) l (Reference 4).

i DET-04-028-3 Revision 0 3-1. 3

The evaluation includes performing a structural analysis of the vent system for the ef fects of LOCA and SRV dis-charge related loads to confirm that the design of the vent system is adequate. Rigorous analytical techniques are used in this evaluation, including use of detailed analytical models for computing the dynamic response of the vent system. Effects such as local penetration and intersection flexibilities are considered in the vent system analysis.

The results of the structural evaluation for each load are used to evaluate load combinations and fatigue ef-fects for the vent system in accordance with the Mark I Containment Program Structural Acceptance Criteria Plant Unique Analysis Application Guide (PUAAG) (Reference 9 5). The analysis results are compared with the accep-tance limits specified by the PUAAG and the applicable sections of the ASME Code (Reference 6).

DET-04-028-3 Revision 0 3-1.4 nutg_qh

r' 3-1. 2 Summary and Conclusions The evaluation documented in this volume is based on the modified Fermi 2 vent system described' in Section 1-2.1. The overall load-carrying capacity of the modi-fled vent system and its supports is substantially greater than that of the original suppression chamber design described in the plants's FSAR.

The loads considered in the original design of the vent system include dead weight loads, OBE and DBE loads, thrust loads, and pressure and temperature loads associated with Normal Operating Conditions and a postu-( lated IDCA event. Additional loadings which affect the design of the vent system, postulated to occur during SBA, IBA, or DBA LOCA events and during SRV discharge events, are defir.cd generically in NUREG-0661. These events result in impact and drag loads on vent system components above the suppression pool, hydrodynamic internal pressure loadings on the vent system, hydro-dynamic drag loadings on the submerged components of the vent system, and in motions and reaction loadings caused by loads acting on structures attached to the vent system.

.DET-04-028-3 Revision 0 3-1.5 nutagh !

The methodology used to develop plant unique loadings for the vent system evaluation is discussed in Section 1-4.0. Applying this methodology results in conserva-tive values for each of the significant NUREG-0661 load-ings which envelop those postulated to occur during an actual LOCA or SRV discharge event.

The LOCA and SRV discharge related loads are grouped into event combinations using the NUREG-0661 criteria discussed in Section 1- 3. 2. The event sequencing and event combinations specified and evaluated envelop the actual events postulated to occur throughout the life of the plant.

Some of the loads contained in the postulated event combinations are major contributors to the total response of the vent system. These include pressur-ization and thrust loads, pool swell impact loads, condensation oscillation downcomer loads, and chugging downcomer lateral loads. Other loadings, such as internal pressure loads, temperature loads, seismic loads, froth impingement and fallback loads, submerged structure loads, and containment motion and reaction loads, although considered in the evaluation, have a lesser ef fect on the total response of the vent system.

DET-04-028-3 Revision 0 3-1. 6 nutech

O The vent system evaluation is based on the NUREG-0661 acceptance criteria, which are discussed in Section 1-3.2. These acceptance limits are at least as restric-tive as those used in the original vent system design documented in the plant's FSAR. Use of this criteria ensures that the original vent system design margins have been restored.

The controlling event combinations for the vent system are those which include the loadings which have been found to be major contributors to the response of the vent system. The evaluation results for these event combinations show that all of the vent system stresses and support reactions are within acceptable limits.

As a result, the modified vent system described in Section 1-2.1 is adequate to restore the margins of  :

safety inherent in the original design of the vent system documented in the plant's FSAR. The intent of ,

the NUREG-0661 requirements as they affect the design adequacy and safe operation of the Fermi 2 vent system are considered to be met.

DET-04-028-3 '

Revision 0 3-1.7 l nutash l l

L. )

= _ _

t 3-2.0 VENT SYSTEM ANALYSIS An evaluation of each of the NUREG-0661 requirements which affect the design adequacy of the Fermi 2 vent system is presented in the sections which follow. The criteria used in this evaluation are contained in Volume 1 of this report.

The component parts of the vent system which are exam- [

ined are described in Section 3-2.1. The loads and load combinations for which the vent system is evaluated are described and presented in Section 3-2.2. The analysis methodology used to evaluate the ef fects of these loads

. O eea 1eea co 81=eeie o eue veae eveee ie ai co ea i-Section 3-2. 4. The acceptance limits to which the anal-ysis results are compared are discussed and presented in Section 3-2. 3. The analysis results and the correspond-ing vent system design margins are presented in Sec-tion 3-2. 5.

i f

I l

( DET-04-028-3

, Revision 0 3-2.1 i

3- 2 .1 _ Component Description The Fermi 2 vent system is constructed from cylindrical shell segments joined together to form a manifold-like structure which connects the drywell to the suppression chamber. The configuration of the vent system is illustrated in Figures 3-2 .1-1 and 3- 2 .1- 2 . The major components of the vent system include the vent lines, vent header, and downcomers. The proximity of the vent system to other components of the containment is shown in Figures 3-2.1-3 through 3- 2 .1- 6 .

The eight vent lines connect the drywell to the vent header in alternate mitered cylinders of the suppression chamber. The vent lines are nominally 1/4" thick and 9

have an inside diameter of 6'-0". The upper ends of the vent lines are 1/2" thick and include a spherical tran-sition segment at the penetration to the drywell, as shown in Figure 3-2.1-7. The drywell shell at each vent line-drywell penetration is 1-1/2" thick and is rein-forced with a 3" thick cylindrical nozzle and a 1-1/2" thick annular pad plate. The vent lines are shielded from jet impingement loads at each vent line-drywell penetration location by jet deflectors which span the openings of the vent lines. The lower ends of the vent DET-04-028-3 Revision 0 3- 2. 2 nutg.ph

- lines are connected to the vent header in the manner of a penstock, as shown in Figure 3-2.1-10. The junction of the vent lines and the vent header are reinforced with 3/4" thick stiffener plates.

The vent header is a continuous assembly of mitered cylindrical shell segments joined together to form a ,

ring header, as shown in Figure 3-2.1-1. The vent header is nominally 1/4" - thick and has an inside dia-meter of 4'-3". Near the vent line-vent header inter-sections, the vent header has an inside diameter of 6'-0". Conical transition segments connect the smaller and larger diameter portions of the vent header. Addi-tional stiffening for the vent line-vent header inter-section is provided by 1-1/2" thick ring plates attached to the vent header transition segments.

A total of eighty downcomers penetrate the vent header in pairs, as shown in Figures 3-2.1-1 and 3-2.1-11. Two downcomer pairs are located in each vent line bay and three pairs are located in each non-vent line bay. Each downcomer consists of an inclined segment which pene-trates the vent header and a vertical segment which terminates below the surface of the suppression pool, as shown in Figure 3-2.1-12. The inclined segment is 3/8" DET-04-028-3

[]' -

Revision 0 3-2. 3

thick and the vertical segment is 1/4" inch thick. Both segments are 2'0" in diameter.

O Full penetration welds connect the vent lines to the drywell, the vent lines to the vent header, and the downcomers to the vent header. As such, the connections of the major components of the vent system are capable of developing the full capacity of the associated major components themselves.

The intersections of the downcomers and the vent header are reinforced with a system of stiffener plates and bracing members, as shown in Figures 3-2.1-11 and 3-2.1-12. In the plane of the downcomers, the inter- g sections are stiffened by a 1/2" thick crotch plate located between downcomers in a pair. The connection of the top side of each downcomer to the vent header is reinforced by 1/2" thick outer stiffener plates.

Downcomer ring plates which are 1" thick connect the associated crotch plate and the outer stiffener plates. This system of stiffener plates is designed to reduce local intersection stresses caused by loads acting on the submerged portion of the downcomers.

DET-04-028-3 Revision 0 3-2.4 h

nutggh

In the direction normal to the plane of the downcomer m

pair, the intersections are braced by 4" diameter Sche-dule 80 pipes. One pipe member is located on each side of the vent header. The upper ends of these pipe members are connected to a built-up tee-section and 3/4" thick pad plates attached to the vent header. The lower ends of the pipe members are connected to the downcomer ring plates. The ring plates are stiffened locally with a 3/4" thick gusset plate and pad plate assembly. In addition, the adjacent downcomer pairs in the non-vent line bay are joined by 2 " diameter rods, one on either side of the vent header. The ends of these rods are connected to the downcomer rings. The bracing system

() provides an additional load path for the transfer of loads acting on the submerged portion of the downcomers and results in reduced intersection local stresses. The system of downcomer-vent header intersection stiffener plates and bracing members provides a highly redundant mechanism for the traasfer of loads which act on the downcomers, thus reducing the magnitude of loads which pass directly through the intersection.

A bellows assembly is provided at the penetration of the vent line to the suppression chamber as shown in Figure l 3-2.1-7 The bellows allow differential movement of the v' DET-04-028-3 Revision 0 3- 2. 5 nutggh

vent system and suppression chamber to occur without developing significant interaction loads. The bellows assemblies consist of a tandem bellows unit with an inside diameter of 6'-9 3/8". A 1-1/2" thick annular plate connects the upper end of the bellows assembly to the vent line. The lower end of the bellows assembly is connected to the suppression chamber by a 1-3/4" thick nozzle. Each of the two bellows units in the assembly contains a section with five convolutions which are alternately connected to 1/2" thick cylindrical sleeves.

The total length of the bellows assembly is 8'-0". The annular nlates are attached to the vent lines with 3/8" partial penetration welds.

9 The SRV piping is routed from the drywell down the vent lines and penetrates the vent lines inside the suppres-sion chamber, as shown in Figures 3- 2 .1-7 and 3- 2 .1- 8 .

The vent lines and SRV piping nozzles are reinforced at each vent line-SRV piping penetration location by a 3/4" thick insert plate, two 1-1/2" thick ring plates, a system of 1-1/2" thick gusset plates, and a 16" diameter 1-1/2" thick sleeve on each SRV piping nozzle. The penetration nozzles are attached to the sleeves at the top and bottom by partial penetration welds as shown in Figure 3-2.1-9. The vent line-SRV piping penetration DET-04-028-3 Revision 0 3-2.6 h

nutgg.h

.- - . - ~. . -

, 1

!. l

' assembly provides an effective means of transferring

. loads which act on the SRV piping to the vent line. -

[ Vent header deflectors are provided in the vent line i

. bays and the non-vent line bays, as shown in

{ - Figures 3-2.1-6, 3-2.1-10, and 3-2.1-12. The deflectors shield the vent header from pool swell impact loads {

which occur during the initial phase of' a DBA event. In .

! the non-vent line bays, the vent header deflectors are

- constructed trom 12" diameter Schedule 120 pipe with 6" rolled tee-sections attached to either side. The i- non-vent line bay deflectors are supported by the- crotch i

h plates at each vent header-downcomer intersection.

In the vent line bays, the vent header deflectors 'are constructed from.1-1/2" thick plate, rolled to the same shape as the vent header deflectors in the non-vent line }

} bays. The vent line 'uay deflectors are supported by the-

] ring plates on the vent line-vent header intersections,  ;

i l ' by the SRV piping support plates on the vent header, and-1 i~ by the crotch plates at each downcomer-vent header j ..

~

j intersection location. The vent beader deflectors are j designed to completely mitigate pool swell impact loads-

on the vent. header.- The vent line bay deflectors also t

i i DET-04-028-3 -

1 Revision O. _3-2.7

-, - , - ,y- , ,-,,,,.-.vw,. r._y._~_.,.-..,.r . _ . - . . . , - . , - , _.e.

, e4, ,r .- ,.- .w., . - - - - ..

shield the SRV piping under the vent header from pool swell impact loads. e The drywell/wetwell vacuum breakers (not shown) are eighteen inches in size and extend from mounting flanges attached to l'-6" diameter, 1" thick nozzles. The nozzles penetrate the vent header at the vent line-vent header intersections, as shown in Figure 3-2.1-10.

Additional support for the vacuum breakers at each vent line-vent header intersection location is provided by a system of ring plates, pad plates, and a 10" diameter Schedule 120 pipe beam. The vacuum breaker support system is designed to reduce local stresses at the intersections of the vacuum breaker nozzles and the vent header. The stiffening also reduces motions of the G vacuum breakers during dynamic events.

The vent system is supported vertically by two column members at each mitered joint location, as shown in Figures 3-2.1-4, 3-2.1-13 and 3-2.1-14. The support column members are constructed from 10" diameter Sche-dule 120 pipe. Built-up clevis assemblies are attached to each end of the columns. The upper ends of the sup-port columns are attached to 3/4" thick vent header ring plates with 2-3/8" diameter pins. The ring plates are DET-04-028-3 Revision 0 3-2.8 nutp_gh a

attached to the vent header with 1/4" fillet welds. The support column ring plates are reinforced at the pin locations by 3/8" thick cover plates which provide addi-tional bearing capacity and by 1" thick gusset and pad plates which provide additional capacity for drag loads acting on the . submerged portion of the support columns.

The lower ends of the support columns are attached to 1-1/2" thick ring beam pin plates with 2-3/8" diameter pins. The support column assemblies are designed to transfer vertical loads acting on the vent system to the suppression chamber ring beams, while simultaneously resisting submerged drag loads.

The vent system is supported horizontally by the vent lines which transfer lateral loads acting on the vent system to the drywell at the vent line-drywell penetra-tion locations. The vent lines also provide additional vertical support for the vent system, although primary vertical support is provided by the vent system support columns. The support offered by the vent line bellows is negligible, since the relative stiffness of the bel-lows with respect to other vent system components is small.

G) DET-04-028-3 Revision 0 3-2.9

The vent system also provides support for a portion of g the SRV piping inside the vent line and suppression chamber, as shown in Figures 3-2.1-3 and 3- 2 .1- 6 . Loads which act on the SRV piping are transferred to the vent system by the penetration assembly on the vent line, and by support plates located under the vent line and vent header. Conversely, loads acting on the vent system causa motions to be transferred to the SRV piping at these same support locations. The wetwell SRV piping is extensively tied to the vent system and is evaluated accordingly.

The overall load-carrying capacities of the vent system component parts described in the preceding paragraphs g are substantially greater than those of the original vent system design described in the plant's FSAR.

DET-04-028-3 3-2.10 h

Revision 0 nutub

N _.)

SEISMIC o RESTRAINT 0 -

VENT LINE PENETRATION k

\

b

' (INFO 30'-6"I.D.

i -

O i

l

/ 0 o 270 56'-3" i @

[

i '

-90 0 p

O,,

g

/

o ,/

/ \ '//

/

VENT #

SYSTEM f C

W N7m /

VENT [

HEADER T 1

NON-VENT i* MITERED LINE BAY I JOINT 180 SUPPRESSION VENTLINEBAY/

MIDCYLINDER Figure 3-2.1-1 p-  !

_.) PLAN VIEW OF CONTAINMENT _

l DET-CA-028-3 Revision 0 3-2.11 N 1

( CONTAINMENT O

EL. 662'-6" g

/

19'-5" I.R.

I 34'-0" I.R.

DRYWELL SHIELD -

BUILDING 7,*$

  • - EL. 597'-0"

\ *

,J , .

o.

37 5' g

4,s VENT LINE o'- e e

.' o BELLOWS */0 SUPPRESSION I

CliAMBER '

/

f i '. N . ,,* *.P .

EL. 572'-1" EL. 562'-8 1/2" .*- *.g,.

2- , s s' i EL. 557'-9" /

EL. 559'-0"

/ \ N. _ _ ,

,1

_f I ,

J 4() . ... .

't .. ,

DOWNCOMER ,

9 l .*

EL. 540'-0" .;.N _  !!Ill ' Ill!l _ /G .

j . * ,

, ,,e , .

k Figure 3-2.1-2 ELEVATION VIEW OF CONTAINMENT g DET-04-028-3 R; vision 0 3-2.12 gg

,l'h G)

N TO t CONTAINMENT SPRAY HEADER BELI4WS

-t VENT VACUUM BREAKER I ,dt) LINE SUPPORT ^ ' *

VENT HEADER Ng 's i /, a s ,

0.587" THICK -i ABOVE t 3'-O" I.R. j 240 56'40"

'%, y , - ) ~

VACUUM BREAKER

~

\

N f

~ I PLATFORM J PIPE L '

7"

~HIGH _ _ _

/ _

_ ~ _ -

tML LATERAL VENT HEADER O DOWNCOMER I

QUENCHER SUPPORT DEFLECTOR 0.658" THICK g PEAM BEI4W t ,

i

' SUPPRESSION QUENCHER CHAMBER SHELL VERTICAL QUENCHER ~ j SUPPORT BEAM ' EL.540'-O"

's

.. f. , '. . <>. ~ ~ . ' . ' * . . ' * . ' .*(.-

, ,* f. J f s . s ., -

Figure 3-2.1-3 n SUPPRESSION CHAMBER SECTION-MIDCYLINDER VENT LINE BAY b

DET-04-028-3 Revision 0 3-2.13 pd

1 O

SUPPRESSION CHAMBER (-*

l TO { CONTAINMENT SHELL

% l SPRAY HEADER MONORAIL 1 RING BEAM CATWALK N

\ l VENT l HEADER

' ' W /

~~10'-1" I.R. ,

IN PLANE RING B N

l. 7 OF R.B. S FFENM r SRV PIPE ,

4 "Tr~

i VENT SYSTEM i

_hu SUPPORT  ! ' LATERAL COLUMN COLUMNS i CONNECTION QUENCHER

\ *' i i\ i SUPPORT l PLATES h RAMSHEAD N

l BEAM -

l1 jl l INSIDE OUTSIDE s l COLUMN g si lh o 1 -

9 i

L e:Lh E-Uet I rIN l e,Jx EL.540'-0"

  • s: . * / l s .'s :, ' a

.,*. i ..,. a-SADDLE VERTICAL QUENCHER l SUPPORT SUPPORT BEAM Figure 3-2.1-4 SUPPRESSION CHAMBER SECTION-MITERED JOINT e

DET-04-028-3 Revision 0 3-2.14 QQfg

TO q CONTAINMENT SPRAY HEADER MONORAIL VENT HEADER

\

l CATWALK 2'-11/2 I.R.

SUPPORT

-4'-11 1/2"

~

~'a u M ,

8'-10 1/2" i

'N / . TM V

/ __l 4'-0* _4'-0",]

15'-3" I.R.

VENT HEADER DEFLECTOR DOWNCOMER QUENCHER j LATERAL QUENCHER VERTICAL QUENCHER SUPPORT BEAM , " ' ' '

  • r SEISMIC RESTRAINT El.540'-0" "I'I 'I'I'I' I s
  • a; *i I 3,. >4.a. ..>;,

. . , 3 . . c; .j . . . '

' GROUT ,

l l

l l Figure 3-2.1-5 t

l SUPPRESSION CHAMBER SECTION l

C\ MIDCYLINDER NON-VENT LINE BAY O l f

1 DET-04-028-3 Revision 0 3-2.15 MdQh

(MIDCYLINDER VENT LINE(

1 VENT HEADER c:s RING BEAM f

\

VACUUM BREAKER \ -

l

-p- SUPPORT BEAM 'l ~

DOWNCOMER BRACING SRV PIPE SUPPORT

> ~3 o

y

- E) r (fi% <

Ifd% )

O n Yl n\r L_

f.~l3

  • N i

I

%$# 1

-5::

./

/

L _

, 3

' _,_ ' " ~ _ ~p ,____ q ; _ _ _. f _ _ _ _ _

~ N - - - - _ - --_ - -

_ _ _ - k _-- __ _

VENT I HEADER DEFLECTOR ER ,

y DOWNCOMER VENT SYSTEM ~ , ~

SRV PIPE l SUPPORT COLUMN I

RAMSilEAD T-QUENCHER

\ >1 +

E_ -0 _

J e  :  : g

$ ,ww 5:

, c . ., r, - - - , , .

.k, SUPPRESSION -VERTICAU QUENCHER CllAMDER SilELL # SUPPORT BEAM

/fALEL.540'-0"

  • . ' . ' < 'd / u ng t,7 s j* .'

o

~ SADDLE SUPPORT -l $

Figure 3-2.1-6 ,

DEVELOPED VIEW OF SUPPRESSION CHAMBER SEGMENT e

DET-04-028-3 RcVision 0 3-2.16 nutEh

O DRYWELL SHELL 1 1/2" THICK INSERT PLATE JET 1 1/2" THICK FLECTOR ANNULAR PAD PLATE SPHERICAL ,

TRANSITION ,'

SEGMENT E  !

)

VENT LINE 1/4" THICK BELLOWS VENT LINE j 1 1/8" THICK INSERT PLATE 13/4" THICK NOZ Z LE

\

\

\

O Ns -

\

\

1/2" THICK VENT LINE 3" THICK CYLINDRICAL NOZ2LE s ,1/2 t/

'N ~ 1/2 [\

\ 1 1/2" THICK i

ANNULAR PLATE SUPPRESSION CHAMBER SHELL t

t F

i Figure 3-2.1-7 VENT LINE DETAILS - UPPER END O

DET-04-028-3 Revision 0 3-2.17 I

e -

w _ m .

gSUPPRESEION CHAMBER SHELL 7 '-6

  • 0. D. x 1 1/2" T:!ICK RING PLATES LINE SRV PIPE VE!C ,- '

LINE SUPPOIC , ,-

s' a'

VENT

/

's HEADER w ', l : ,, - 1 1/ 8 " THICK I i INSERT PLATE

\ V N l Ap

\ at? s

\ SRV PIPE PENETRATION

-N" <

\ ASSEMBLY SRV PIPE VENT LINE ELEVATION VIEW l 1/2" THICK OUTER GUSSET PLATE (TYP)

F j

1 1/2" THICK 16

  • O . D . x 1 1/2" IB B GUSSET PLATE (TYP)

THICK SLEEVE jg , j

== -

i-

\ x; ,

-nm L

i 3/4" THICK INSERT PLATE VIEW A-A I'igure 3-2,1-8 VENT LINE DETAILS - LOWER END e

DET-04-028-3 Revision 0 3-2.18 ON Et-

/"N V

3/4" TIIICK ( SRV PIPE INSERT PLATE i I

(3/4 Q

, s~"y

% /

% 9 ,

)b % i $

/  %

/ % f

  1. g

/ r f %

/ #%

l / k

/ % p%

AIR SPACE M%  % 1 1/2" THICK GUSSET PLATE 3/16" MAX. #7 g / %

/ #%

// % I h\l6" O.D. x 1 1/2" k pk I THICK SLEEVE

-m ~ A 5/8 \

1/4 [ ,

SECTION B-B ,

i

./

l Figure 3-2.1-9

, VENT LINE-SRV PIPING PENETRATION C) NOZZLE DETAILS 4

V DET-04-028-3 Revision 0 3-2.19 (t

{' VENT LINE I

h A 3/4" THICK INTERSECTION STIFFENER PLATES VENT HEADER i 43 I,p,.

.-p ,

/ '

N

, ~

_ 0 -- -

i t t ,

5 _ _ _ _w , , , , . _D

?,- _ _ _ws,

, , , ,g.___.

L

~

~ i . J" ); L .36 10" @ SCH 120 A VACUUM BREAKER 1 1/2" THICK' SUPPORT BEAM NT HEADER STIFFENER RINGS PLAN VIEW

( VENT HEADER 1 1/2" THICK SUPPORT PLATE 3'-0" I.R.

VACUUM BREAKER j NO2ILE  %

Nw ,

I

\ s- t

/

2'-4* O.D. x l' THICK RING PLATg 3'-7 $/8" d

- D SRV PIPE e 1 1/2" THICK VENT HEADER DEFLECTOR SECTION A-A Figure 3-2.1-10 VENT LINE-VENT HEADER INTERSECTIOt DETAILS DET-04-028-3 O

Revision 0 3-2.20 nutggh

)

O ftITERED JOINT-BUILT-UP TEE AND PAD PLATE 3/4" THICK SUPPORT (MIDCYLINDER /

$ /j r g :q VENT (- - -

r. h_ _ r_ h_ _ a \- s ( %.

Q _ _

__y 4

J ,

()

5

/ 2" Gr gm 4" OSCH 80 g3 ROD BRACING O l l MEMBERS l 3/4" THICK GUSSET AND PAD PLATE DOWNCOMER Figure 3-2.1-11 DEVELOPED VIEW OF VENT HEADER AND DOWNCOMER BRACING SYSTEM O

DET-04-028-3

. Revision 0 3-2.21 nutagh

O

, , , (VENTHEADER 1/2" THICK OUTER '

1/2" THICK STIFFENER PLATE -~ ~

CROTCH PLATE

/

/ '

1/2" THICK CONNECTION 1" THICK g PLATE DOWNCOMER , s RING PLATE 2'-0" O.D. ,

3/8" THICK _

4 _

l O

l WT 6x26.5 2'-0" O.D. 12" O SCH 120 1/4" THICK VENT HEADER DEFLECTOR Figure 3-2.1-12 DOWNCOMER - VENT HEADER INTERSECTION DETAILS DET-04-028-3 a, Revision 0 3-2.22 nut l

{ VENT HEADER

( 3/4"Tl!ICK+\

RING PLATE c 3 '-0 5/16" RADIUS

/

3/8" T!!ICK g COVER PLATE N ,

x

{

4 A

.h.

4A i

SECTION THRU VENT HEADER AT COLUMN SUPPORT RING PLATE

,O U

VENT HEADER i' .

^u ;]: " Ti .i

_] :/ >

1" THICK GUSSET PLATE

\ "

1" THICK PAD PLATE SECTION A-A Figure 3-2.1-13 A

O SUPPORT COLUMN RING PLATE DETAILS DET-04-028-3 OUk Revision 0 3-2.23

1 3/4" THICK PIN PLATE A

I h

,)

~

T ~ ~

~

2 1/4" x 13" # I END PLATE I A  !

10" g SCH 120 l {

PIPE 4 l  ; l i

! I I d D 15'-8 3/8" (Nominal)  ; I g l 1  ! ' I ll 'd ji l I II lI I il i I 12" g SCH 140% ll I l[ l PIPE SLEEVE ll I ll l l' I l'____ ___M O I  !  ! t l 2 1/4 " x 15" g "'4 END PLATE T_ _ _

~-] +

1 3/4" THICK -

PIN PLATE I

I Figure 3-2.1-14 VENT SYSTEM SUPPORT COLUMN DETAILS h

DET-04-028-3 Rsvision 0, 3-2.24 py{

1

3-2.0 Loads and Load Combinations The loads for which the Fermi 2 vent system is evaluated are defined in NUREG-0661 on a generic basis for all Mark I plants. The methodology used to develop plant unique defined vent system loads for' each load in NUREG-0661 is discussed in Section 1-4.0. The results of applying the methodology to develop specific values for each of the governing loads which act on the vent system are discussed and presented in Section 3-2.2.1.

Using the event combinations and event sequencing defined in NUREG-0661 and discussed in Sections 1-3.2 and 1-4. 3, the controlling load combinations which affect the vent system are formulated. The controlling 1 vent system load combinations are discussed and pre-sented in Section 3-2.2.2.

l l

i i

O DET-04-028-3 -

! Revision 0- 3-2.25 l

l

3- 2 . 2 .1 Loads g The loads acting on the vent system are categorized as follows:

1. Dead Weight Loads
2. Seismic Loads
3. Pressure and Temperature Loads
4. Vent System Discharge Loads
5. Pool Swell Loads
6. Condensation Oscillation Loads
7. Chugging Loads
8. Safety Relief Valve Discharge Loads
9. Piping Reaction Loads
10. Containment Interaction Loads h Loads in categories 1 through 3 were considered in the original containment design as documented in the plant's FSAR. Additional category 3 pressure and temperature loads result from postulated LOCA and SRV discharge events. Loads in categories 4 through 7 result from postulated LOCA events; loads in category 8 result from SRV discharge events; loads in category 9 are reactions which result from loads acting on SRV piping systems; loads in category 10 are motions which result from loads acting on other containment-related structures.

DET-04-028-3 Revision 0 3-2.26 nutggh)

V. ,

4 Not all of the loads defined in NUREG-0661 are evaluated in detail since some are enveloped by others or have a-negligible ef fect on the vent system. Only those loads which maximize the vent system response and lead to controlling stresses are, fully evaluated and discussed.

These loads are referred to as governing loads in sub-sequent discussions.

Table 3-2.2-1 shows the specific vent system components which are affected by each of the loadings defined in NUREG-0661. The table also lists the section in volume 1 in which the methodology for developing values O for each loading is discussed. The magnitudes and char-

acteristics of each governing vent system load in each load category are identified and presented in the para-graphs-which follow. ,

i

1. Dead Weight Loads
a. Dead Weight of Steel
The weight of steel i used to construct the modified vent system and its supports is considered. The nominal component dimensions and a density of steel.of 3

490 lb/ft are used in this calculation.

~

DET-04-028-3 Revision 0 3-2.27 i

2. Seismic Loads
a. OBE Loads: The vent system is subjected to horizontal and vertical accelerations during an Operating Basis Earthquake (OBE). This loading is taken from the original design basis for the containment documented in the plant's FSAR. The OBE loads have a maximum horizontal spectral acceleration of 0.239 and a maximum vertical spectral acceleration of 0.0679
b. SSE Loads: The vent system is subjected to e

horizontal and vertical accelerations during a Safe Shutdown Earthquake (SSE). This loading is taken from the original design basis for the containment documented in the plant's FSAR

[ termed Design Basis Earthquake (DBE) in the PSAR]. The SSE loads have a maximum horizon-tal spectral acceleration of 0.46g and a maximum vertical spectral acceleration of 0.133g.

3. Pressure and Temperature Loads
a. Normal Operating Internal Pressure Loads: The vent system is subjected to internal pressure DET-04-028-3 Revision 0 3-2.28 g

nutggb

loads during Normal Operating conditions.

This loading is taken from the original design basis for the containment documented in the

' plant's FSAR. The range of normal operating internal pressures specified is 0.0 to 2.0 psi.

b. LOCA Internal Pressure Loads: The vent system is subjected to internal pressure loads during a Small Break Accident (SBA), Intermediate Break Accident (IBA), and Design Basis Accident (DBA) event. The procedure used to develop LOCA internal pressures for the con-tainment is discussed in Section 1-4.1.1. The resulting vent system internal pressure tran-sients and pressure magnitudes at key times during the SBA, IBA, and DBA events are
presented in Figures 3-2.2-1 through 3-2.2-3.

The vent system internal pressures for each event are conservatively assumed to be equal to the corresponding drywell internal pres-sures, neglecting reductions due to losses.

The net internal pressures acting on the com-l ponents of the vent system inside the suppres-l DET-04-028-3 y Revision 0 3-2.29

sion chamber are taken as the difference in pressures between the vent system and suppres-sion chamber.

The pressures apecified are assumed to act uniformly over the vent line, vent header, and downcomer shell surfaces. The external or secondary containment pressure for the vent system components outside the suppression chamber for all events is assumed to be zero.

The effects of internal pressure on the vent system for the DBA event are included in the pressurization and thrust loads discussed in load case 4a. g

c. Normal Operating Temperature Loads: The vent system is subjected to the thermal expansion loads associated with normal operating conditions. This loading is taken from the original design basis for the containment documented in the plant's FSAR. The range of normal operating temperatures for the vent system with a concurrent SRV discharge event is 50 to 150*P. The temperature of the SRV DET-04-028-3 Revision 0 3-2. 30 l

l nutggh)

piping with a concurrent SRV discharge event is conservatively taken as 363*F.

Additional normal operating temperatures for the vent system inside the suppression chamber are taken from the suppression pool tempera-ture response analysis. The resulting vent system temperatures are summarized in Table 3-2.2-2.

d. IDCA Temperature Loads: The vent system is subjected to thermal expansion loads associ-4 ated with the SBA, IBA, and DBA events. The l

O' procedure used to develop LOCA containment temperatures is discussed in Section 1-4.1.1.

The resulting vent system temperature tran-sients and temperature magnitudes at key times during the SBA, IBA, and DBA events are pre-sented in Figures 3-2. 2-4 th rough 3-2. 2-6.

Additional vent system SBA event temperatures are taken from the suppression pool tempera-ture response analysis. The resulting vent system temperatures are summarized in Table J

3-2.2-2. The greater of the . temperatures O

V 4

DET-04-028-3 Revision 0 3-2. 31

. . . . - - _ _ ~ _ , . s-- .- , -

..wy

specified in Figure 3- 2 , 2- 4 and Table 3- 2. 2-2 g is used in evaluating the effects of dBA event temperatures.

The temperatures of the major components of the vent system, such as the vent line, vent header, and downcomers, are conservatively assumed to be equal to the corresponding dry-well temperatures for the IBA and DBA events.

For the SBA event, the temperature of the major components of the vent system is assumed to be equal to the maximum saturation tempera-ture of the drywell, which is 270*F.

9 The temperatures of the external components of the vent system such as the support columns, downcomer bracing, vent header deflectors, vacuum breaker supports, and associated ring plates and stiffeners are assumed to be equal to the corresponding suppression chamber tem-peratures for each event.

The temperatures specified are assumed to be represent **ive of the major component and DET-04-028-3 Revision 0 3-2. 32 g nutp_qh

l A ~

external component metal temperatures through-out the vent system. The temperature of the SRV piping for those SBA, IBA, and DBA events which include SRV discharge loads is taken as 36 3*F. The ambient or initial temperature of the vent system for all events is assumed to be equal to the arithmetic mean of the minimum and maximum vent system operating temperatures.

4. Vent System Discharge Loads
a. Pressurization and Thrust Loads: The vent system is subjected to pseudo-static pressuri-

" O zation and thrust loads during a DBA event.

The procedure used to develop vent system pressurization and thrust forces, applied to the unreacted areas of the major components of the vent system, is discussed in Section 1-4.1.2. The resulting maximum forces for each of the major component unreacted areas at key times during the DBA event are shown in Table 3-2. 2- 3. The pressurization loads acting on the vent line-drywell penetrations are obtained by multiplying the corresponding drywell internal pressures for the DBA event p by the penetration unreacted area.

O i

~DET-04-028-3  ;

Revision 0 3-2.33 <

l l

i I

O The vent system discharge loads shown include the effects of zero drywell/wetwell pressure differential. The vent system discharge loads specified for the DBA event include the effects of DBA internal pressure loads as discussed in load case 3a. The vent system discharge loads which occur during the SBA or IBA events are negligible.

5. Pool Swell Loads
a. Vent System Impact and Drag Loads: During the initial phase of a DBA event, transient impact and dra'l pressures are postulated to act on major components of the vent system above the suppression pool. The major components affected include the vent line inside the sup-pression chamber below the maximum bulk pool height and the inclined portion of the down-comers below the downcomer rings. The upper portion of the downcomers is shielded from pool swell impact loadd by the downcomer rings. The vent header in the vent line bay and non-vent line bay is shielded from pool swell impact loads by the vent header deflec-tors.

O DET-04-028-3 Revision 0 3-2. 34 gg

O The procedure used to develop the transient forces and the spatial distribution .of pool.

swell impact loads on these components is discussed in Section 1-4.1.4. The resulting magnitudes and distribution of pool swell  ;

f impact loads on the vent line, downcomers, and vent header deflector are summarized in Table 3-2.2-4, and Figures 3-2.2-7 and 3-2.2-8. The i

results shown are based on plant unique QSTP test data contained in the PULD (Reference 3) and include the effects of the main vent orifice tests. Pool swell loads do not occur during the SBA and IBA events.

b. Impact and Drag Loads on Other Structures

During the initial phase of a DBA event, transient impact and drag pressures are postu- ,

lated to act on the components of the vent-system other than the major components. The components affected include the downcomer bracing members and ring plates, the vacuum breaker and vacuum breaker supports, and the SRV piping and supports located beneath the t vent line. The portion of the SRV piping DET-04-028-3 Revision 0 3-2. 35 nutagh

located under the vent header is shielded from pool swell impact loads by a vent header deflector.

The procedure used to develop the transient forces and the spatial distribution of pool swell impact loads on these components is discussed in Section 1-4.1.4 The resulting magnitudes and distribution of pool swell impact pressures on the downcomer bracing members and ring plates, and the vacuum breaker and vacuum breaker supports are sum-marized in Table 3- 2 . 2- 5 . The pool swell impact loads on the SRV piping and supports h

located beneath the vent line are presented in Volume 5 of this report. The results shown are based on plant unique QSTP test data contained in the PULD which are used to determine the impact velocities and arrival times. Pool swell loads do not occur during the SBA and IBA events,

c. Froth Impingement and Fallback Loads: During the initial phase of a DBA event, transient impingement pressures are postulated to act on DET-04-028-3 R: vision 0 3-2. 36 h

nutggb

p d components of the vent system located in spec-ified regions above the rising suppression pool. The components located in Region I which are affected include the downcomer-bracing cembers and ring plates, the vacuum breaker and vacuum breaker supports and the SRV piping supports beneath the vent line.

The components located in Region II which are af fected include the vacuum breaker and vacuum breaker supports.

The procedure used to develop the transient forces and spatial distribution of froth impingement and fallback loads on these com-ponents is discussed in Section 1-4.1.4. The resulting magnitudes and distribution of froth impingement and fallback pressures on the downcomer bracing members and ring plates, and the vacuum breaker and vacuum breaker supports are summarized in Table 3- 2 . 2- 6 . The froth impingement loads acting on the SRV piping and supports located beneath the vent line are presented in Volume 5 of this report. The results shown include the ef fects of using the plant unique QSTF movies to determine the A

U- DET-04-028-3 Revision 0 3- 2. 37 f

source velocity, departure angle, and froth density. Pool swell loads do not occur during the SBA and IBA events.

d. Pool Fallback Loads: During the later portion of the pool swell event, transient drag pressures are postulated to act on selected components of the vent system located between the maximum bulk pool height and the downcomer exit. The components affected include the downcomer bracing members and ring plates, and the SRV piping and supports located beneath the vent line. The procedure used to develop transient drag pressures and spatial distribu- g tion of pool fallback loads on these compo-nents is discussed in Section 1-4.1.4.

T h <: resulting magnitudes and distribution of pool fallback loads on the downcomer bracing members and ring plates are summarized in Table 3- 2. 2-7 . The pool fallback loads on the SRV piping and supports located beneath the vent line are presented in Volume 5 of this report. The results shown include the effects of maximun pool displacements measured in DET-04-028-3 Revision 0 3-2. 38 h

nutp_ql)

\g s) plant unique QSTP tests. Pool swell loads do not occur during the SBA and IBA events.

e. IOCA Air Clearing Submerged Structure Loads:

Transient drag pressures are postulated to act on the submerged components of the vent system -

during the air clearing phase of a DBA event. The components affected include the downcomers, the support columns, and the sub-nerged portion of the SRV piping. The proce-dure used to develop the transient forces and spatial distribution'of DBA air clearing drag loads on these components is discussed in Section 1-4.1.6.

The resulting magnitudes and distribution of drag pressures acting on the downcomers and the vent system support columns for the con-trolling DBA air clearing load-case are shown in Tables 3-2.2-8 and 3-2.2-9. The control-ling DBA air clearing loads on the submerged.

portion of the SRV piping are presented in Volume 5 of this - report. The results shown include the ef fects of velocity drag, acceler-ation drag, and interference effects. The C.)3 DET-04-028-3 Revision 0 3-2. 39

LOCA air clearing submerged structure loads which occur during an SBA or IBA event are negligible.

6. Condensation Oscillation Loads
a. IBA Condensation Oscillation Downcomer Loads:

llarmonic internal pressure loads are postu-lated to act on the downcomers during the condensation oscillation phase of an IBA event. The procedure used to develop the harmonic pressures and spatial distribution of IBA condensation oscillation downcomer loads is discussed in Section 1-4.1.7. The loading consists of a uniform internal pressure compo- g nent acting on all downcomers and a differen-tial internal pressure component acting on one downcomer in a downcomer pair. The resulting pressure amplitudes and ussociated frequency range for each of the three harmonics in the IBA condensation oscillation downcomer loading are shown in Table 3-2.2-10. The correspond-ing distribution of differential downcomer internal pressure loadings are shown in Figure 3- 2. 2-9 .

DET-04-028-3 Revision 0 3-2.40 nutggh

S

The IBA condensation oscillation downcomer-v load harmonic in the range of the dominant downcomer frequency for the uniform and the differential pressure components is applied at the dominant downcomer frequency. The remain-ing two downcomer load harmonics are applied at frequencies which are multiples of the ,

dominant frequency. The results of the three harmonics for the uniform and differential IBA condensation oscillation downcomer. load compo-

~

nents are summed absolutely.

l DBA Condensation Oscillation Downcomer Loads:

b.

2 l Harmonic internal pressure loads are postu-lated to act on the downcomers during the ,

condensation oscillation phase of a DBA event.

The procedure used to develop the harmonic i

pressures and spatial distribution of DBA i.

condensation oscillation downcomer loads is the same as that discussed for IBA condensa-tion oscillation downcomer loads in load case 6a. The resulting . pressure amplitudes and associated frequency range for each of the three. harmonics in the DBA condensation oscil- -i lation downcomer~ loading are shown in Table O* oer-o4-o28-3

Revision 0 3-2.41 l

+

3-2.2-11. The corresponding distribution of h

differeatial downcomer internal pressure load-ings are shown in Figure 3- 2 . 2- 9 .

c. IBA Condensation Oscillation Vent System Pres-sure Loads: Harmonic internal pressure loads are postulated to act on the vent system dur-ing the condensation oscillation phase of an IBA event. The components affected include the vent line, the vent header, and the down-comers. The procedure used to develop the harmonic pressures and spatial distribution of IDA condensation oscillation vent system pres-sures is discussed in Section 1-4.1.7. The resulting pressure amplitudes and associated frequency range for the vent line and vent header are shown in Table 3-2.2-12. The load-ing is applied at the frequency within a spec-ified range which maximizes the vent system response.

The effects of IBA condensation oscillation vent system pressures on the downcomers are included in the IBA condensation oscillation downcomer loads discussed in load case 6a. An DET-04-028-3 Revision 0 3-2.42 nutggh

l' additional static internal pressure of 1.5 psi is applied uniformly to the vent line, vent header, and downcomers to account for the effects of nominal downcomer submergence. The IBA condensation oscillation vent system pres-sures act in addition to the IBA containment internal pressures discussed in load case 3a.

d. DBA Condensation Oscillation Vent System Pres-sure Loads: Ilarmonic internal pressure loads are postulated to act on the vent system during the condensation oscillation phase of a DBA event. The components affected include O)

\_ the vent line, vent header, and the down-comers. The procedure used to develop the harmonic pressures and spatial distribution of

, the DBA condensation oscillation vent system pressures is the same as that discussed for the IBA in load case 6c. The resulting pres-sure amplitudes and associated frequency range for the vent line and vent header are shown in Table 3-2. 2-12. The DBA condensation oscilla-tion vent system pressures act in addition to the DBA vent system pressurization and thrust loads discussed in load case 4a.

A DET-04-028-3

~

Revision 0 3-2.43

e. IBA Condensation Oscillation Submerged Struc-ture Loads: Ilarmonic pressure loads are postulated to act on the submerged components of the vent system during the condensation oscillation phase of an IBA event. In accor-dance with NUREG-0661, the submerged structure loads specified for pre-chug are used in lieu of IBA condensation oscillation submerged structure loads. Pre-chug submerged structure loads are discussed in load case 7c.
f. DBA Condensation Oscillation Submerged Struc-ture Loads: Harmonic drag pressures are pos-tulated to act on the submerged components of the vent system during the condensation oscil-lation phase of a DBA event. The components affected include the support columns and the submerged portions of the SRV piping. The procedure used to develop the harmonic forces and spatial distribution of DBA condensation oscillation drag loads on these components is discussed in Section 1-4.1.7.

DET-04-028-3 Revision 0 3-2.44 g

nutech

O to ds ere devetoged for the ceee with the average source strength at all downcomers and '!

the case with twice the average source strength at the nearest downcomer. The results of these two cases are evaluated to-determine the controlling loads.

The resulting magnitudes and distribution of drag pressures acting on the support columns for the controlling DBA condensation oscilla-tion drag load case are shown in Table 3-2. ?-13. The controlling DBA condensation oscillation drag loads on the submerged i portion of the SRV piping are presented in l Volume 5 of this report. The ef fects of DBA condensation oscillation submerged structure  ;

loads on the downcomers are included in the f loads discussed in load case 6b.

The results shown in Table 3-2.2-13 include the effects of velocity drag, acceleration drag, torus shell FSI acceleration drag, interference effects, and acceleration drag volumes. A typical pool acceleration profile q

from which the FSI accelerations are derived -

.J l

U t

DET-04-028-3 --

Revision 0 3-2.45 i

is shown in Figure 3-2.2-10. The results of g each harmonic in the loading are combined using the methodology discussed in Section 1-4.1.7.

7. Chugging Loads t
a. Chugging Downcomer Lateral Loads: Lateral loads are postulated to act on the downcomers during the chugging phase of an SBA, IBA, and DBA event. The procedure used to develop chugging downcomer lateral loads is discussed in Section 1-4.1.8. The maximum lateral load acting on any one downcomer in any direction is obtained using the maximum downcomer lat-h eral Icad and chugging pulse duration measured at FSTF, the frequency of the tied downcomers for FSTF, and the plant unique downcomer fre-quency calculated for Fermi. This information is summarized in Table 3-2. 2-14. The result-ing ratio of Fermi to FSTF Dynamic Load Factors (DLF) is used in subsequent calcula-tions to determine the magnitude of multiple

, downcomer loads and to determine the load t

magnitude used for evaluating fatigue. The methodology used to determine the plant unique s

! DET-04-028-3 Revision 0 3-2.46 is , .

., nutggh w*

a l

I 7

T I

's/

downcomer frequency is discussed in Section l I

a-3-2.4.1. -

I J

The magnitude of chugging lateral loads acting on multiple downcomers simultaneously is de-termined using the methodology described in Section 1-4.1.8. The methodology involves calculation of the probability of exceeding a given downcomer load magnitude once per LOCA I as a function of the number of downcomers loaded. The chugging load magnitudes, shown 1< in Table 3-2.2-15, are determined using the resulting non-exceedance probabilities and the iO i ratio of the DLP's taken for the maximum down-comer load calculation. The distributions of chugging downcomer lateral loads which are considered include those cases which maximize local effects in the vent system and those cases which maximize overall effects in the vent system. These distributions are summar-ized in Tables 3-2.2-16 and 3-2. 2-17.

6 The maximum downcomer lateral load magnitude used for evaluating - fatigue is obtained'using .I the maximum downcomer lateral load measured at  !

\

,,l-- l 1

DET-04-028-3 Revision 0 3-2.47

, i '

FSTP with a 95% NEP, and the ratio of DLF's taken from maximum downcomer load calcula-tions. The stress reversal histograms pro-vided for FSTF are converted to plant unique stress reversal histograms using the postu-1 lated plant unique chugging duration as shown in Table 3-2.2-18.

b. Chugging Vent System Pressures: Transient and harmonic internal pressures are postulated to act on the vent system during the chugging phase of an SBA, IBA, and DBA event. The components affected include the vent line, the vent header, and the downcomers. The proce-dure used to develop chugging vent system 9

pressures is discussed in Section 1-4.1.8.

The load consists of a gross vent system pres-sure oscillation component, an acoustic vent system pressure oscillation component, and an acoustic downcomer pressure oscillation compo-nent. The resulting pressure magnitudes and characteristics of the chugging vent system pressure loading are shown in Table 3-2.2-19.

The three load components are evaluated individually and are not combined.

DET-04-028-3 Revision 0 3-2.48 g

nutggh

I 4

I i

The overall effects of chugging vent system pressures on the downcomers are included in r l the loads discussed in load case 7a. The f downcomer pressures shown in Table 3-2.2-19  :

are used to evaluate downcomer hoop stresses. f The chugging vent system pressures act in addition to the SBA and IBA containment internal pressures discussed in load case 3a i

'l and the DBA pressurization and thrust loads discussed in load case 4a.

c. Pre-Chug Submerged Structure Loads: During 4 the chugging phase of an SBA, IBA, or DBA ,

event, harmonic drag pressures associated with the pre-chug portion of a chug cycle are pos-tulated to act on the submerged components of the vent system. The components affected include the support columns and the submerged 6

portion of the SRV piping. The procedure used  ;

to develop the harmonic forces and spatial  ;

-t distribution of pre-chug drag loads on these components is discussed in Section 1-4.1.8. l i

h DET-04-028 !

-Revision 0 3-2.49 .

Loads are developed for the case with the average source strength at all downcomers and O

the case with twice the average source strength at the nearest downcomer. The re-sults of these two cases are evaluated to determine the controlling loads. The re-sulting magnitudes and distribution of drag pressures acting on the support columns for the controlling pre-chug drag load case are shown in Table 3-2.2-20. The controlling pre-chug drag loads on the submerged portion of the SRV piping are presented in Volume 5 of this report. The offects of pre-chug sub-merged structure loads on the downcomers are included in the loads discussed in load case 7a.

The results shown include the offects of velo-city drag, acceleration drag, torus shell PSI acceleration drag, interference effects, and acceleration drag volumes. A typical pool acceleration profile from which the PSI accelerations are derived is shown in Figure 3-2.2-10.

DET-04-028-3 Revision 0 3-2.50 g

nutggh

l O d. Post-Chug Submerged Structure Loads: During the chugging phase of an SBA, IBA, or DBA event, harmonic drag pressures associated with the post-chug portion of a chug cycle are postulated to act on the submerged comportents of the vent system. The components affected include the support columns and the submerged portion of the SRV piping. The procedure used to develop the harmonic forces and spatial distribution of pre-chug drag loads on these components is discussed in Section 1-4.1.8.

O toea are aeve1eeea cor eue ce e- ith eue average source strength at the nearest two downcomers acting both in phase and out-of phase. The results of these cases are evaluated to determine the controlling loads. The resulting magnitudes and distribu-tion of drag pressures acting on' the vent system support columns for the controlling post-chug drag load case are shown in Table 3-2.2-21. The controlling post-chug drag loads on the submerged portion of the SRV piping are presented in Volume 5 .of this l DET-04-028-3 3-2.51 Revision 0

report. The effects of post-chug submerged g structure loads acting on the downcomers are included in the chugging downcomer lateral loads discussed in load case 7a.

The results shown include the ef fects of velo-city drag, acceleration drag, torus shell PSI acceleration drag, interference effects, and acceleration drag volumes. A typical pool acceleration profile from which the FSI accelerations are derived is shown in Figure 3-2.2-10. The results of each harmonic are combined using the methodology described in Section 1-4.1.8. g

8. Safety Relief Valve Discharge Loads
a. SRV Discharge Air Clearing Submerged Structure Loads: Transient drag pressures are postu-lated to act on the submerged components of the vent system during the air clearing phase of an SRV discharge event. The components l affected include the downcomers, support col-umns, and the submerged portion of the SRV piping. The procedure used to develop the transient forces and spatial distribution of DET-04-028-3 Revision 0 3-2.52 h

nutg_qh

i the SRV discharge air clearing drag loads on these components is discussed in Section 1-4.2.4.

Loads are developed for the case with four bubbles from quenchers in three consecutive bays acting in phase and the case with four bubbles from quenchers in two adjacent bays acting in phase. These results are evaluated to determine the controlling loads. A cali-bration factor is applied to the resulting downcomer loads developed using the method-ology discussed in Section 1-4.2.4. The mag-fl nitudes and distribution of drag pressures v

acting on the downcomers and the support col-umns for the controlling SRV discharge drag load case are shown in Tables 3-2.2-22 and 3-2.2-23.

These results include the ef fects of velocity drag, acceleration drag, interference effects, acceleration drag volumes, and the additional load mitigation effects of the 20" diameter T quencher.

(,_,) DET-04-028-3 Revision 0 3-2.53 nutggh

9. Piping Reaction Loads
a. SRV Piping Reaction Loads: Reaction loads are O

induced on the vent system due to loads acting on the drywell and wetwell SRV piping systems.

These reaction loads occur at the vent line-SRV piping penetrations and at the SRV piping supports located beneath the vent lines and vent header. The SRV piping reaction loads consist of those caused by motions of the vent system and loads acting on the drywell and wetwell portions of the SRV piping systems.

Loads acting on the SRV piping systems include pressurization and thrust loads, elevated structure loads, submerged structure loads, and other operating or design basis loads.

The effects of the SRV piping reaction loads on the vent system are included in the vent system analysis. The reaction loads for the drywell portion of the SRV piping are taken from Volume 5 of this report.

i

10. Containment Interaction Loads

! a. Containment Structure Motions: Loads acting on the drywell, suppression chamber and vent DET-04-028-3 Revision 0 3-2.54 g

nutgch

system cause interaction effects between these structures. The interaction effects result in vent system motions applied at the attachment points of the vent system to the drywell and the suppression chamber. The effects of these motions on the vent system are considered in the vent system analysis.

The values of the loads presented in the preceding para-graphs envelop those which could occur during the LOCA and SRV discharge events postulated. An evaluation for the effects of the above loads results in conservative estimates of the vent system responses and leads to bounding values of vent system stresses.

i i

i DET-04-028-3 Revision 0 3-2.55 l <

-c.

l Table 3-2, i

/

VENT SYSTEM COMPONENT LC s

Volume 3 Load Designation PUAR Section Reference Case Category Load Type Number Dead Weight Dead weight of Steel la 1-3.1 Loads Seismic

. OBE Seismic Loads 2a 1-3.1 Loads SSE Seismic Loads 2b l-3.1 Normal Operating Internal Pressure 3a 1-3.1 Temperature LOCA Internal Pressure 3b 1-4.1.1 Loads Normal Operating Temperature Loads 3c l-3.1 LOCA Temperature Loads 3d 1-4.1.1 Vent System Pressurization and Thrust Loads 4a 1-4.1.2 Discharqe Vent System Impact and Draq Loads Sa 1-4.1.4.1 Impact and Drag Loads on other Structures 5b l-4.1.4.2 Pool Swell Froth Impingement & Fallback Loads Sc 1-4.1.4.3 Loads Pool Fallback Loads 5d 1-4.1.4.4 LOCA Water Clearing Submerged Structure Loi ds N/A 1-4.1.5 LOCA Air Clearing Submerged Structure Loads Se 1-4.1.6 IBA C.O. Downcomer Loads 6a 1-4.1.7.2 DBA C.O. Downcomer Ioads 6b l-4.1.7.2 Condensation IBA C.O. Vent System Pressure Loads 6c l-4.1.7.2 Oscillation Loads DBA C.O. Vent Systen Pressure Loads 6d 1-4.1.7.2 IBA C.O. Submerged Structure Loads 6e 1-4.1.7.3 DBA C.O. Submerged Structure Loads 6f 1-4.1.7.3 Chugging Downcomer Lateral Loads 7a 1-4.1.8.2 Chugging Chugging Vent System Pressures 7b l-4.1.8.2 Loads Pre-Chug Submerged Structure Loads 7c l-4.1.8.3 Post-Chug Submerced Structure Loads 7d 1-4.1.8.3 SRV Discharge Water Clearing SRV Discharge submerced Structure Loads N/A 1-4.2.4 Loads SRV Discharge Air Clearing Submerced Structure Ioads 8a 1-4.2.4 Piping Reaction SRV riping Reaction Loads 9a Vol. 5 Loads Containment Interaction Containment Structure Motions 10a vol. 2 loads DET-04-028-3

\ Revision 0 3-2.56

' N.

~

$-1 LDING INFORMATION l

Component Part Loaded l i

! c M c k N 4

~#

et W 5m 13 h 3

4 0 8

o ae oc oe k c by Remarts Eou N ao cc UO P$ e$?

c- ce cmu 5m

$ $b bb$ l hc a? $3 $$ $$ $$$ 0 S a- Oca 0$ 50 $55 l

lX X X X X X X X X As-modified geometry X X X X X X X X X 0.239 horizontal, 0.0679 vertical i j 0.46g horizontal, 0.1339 vertical 7

lX X X X X 0.0 to 2.0 psi l

X X X t. X SBA, IBA, & DBA pressures lX X X X X X X X X 50 to 150 "P I X X X X X X X X X SBA, IBA & DBA temperatures X X X X Forces on unreacted areas X X X lieader shielded by deflectors X X Components below max pool height Y X Two regions specified i X Major components not affected X Effects negligible X X Primarily local effects X Uniform & differential components X Uniform & differential components lX X X Downcomer pressures included in 6a lX X X Downcomer pressures included in 6b X Downcomer loads included in 6a X Downcomer loads included in 6b X

RSEL based on FSTF

'X X X Three loading alternates X I y Downcomer loads . included in 7a X Downcomer loads included in 7a Effects negligible v

x x Primarily local effects X X Reactions on vent line & header Drywell & torus motions nutg,qh

l l

l l

Table 3-2.2-2 SUPPRESSION POOL TEMPERATURE RESPONSE ANALYSIS RESULTS-MAXIMUM TEMPERATURES (1) Number Maximum Bulk Condition f SRV's Pool Numb r Temperature (gF)

Actuated lA 1 154.0 1B 1 172.0 Normal 2A 5 165.0 Operating

() 2B 1 162.0 2C 5 168.0 SBA

^

  • Event 3B 5 169.0 Note:
1. See Section 1-5.1 for a description of SRV l discharge events.

I l

i fN DET-04-028-3

\l Revision 0 3-2.57 nutg_qh

Table 3-2.2-3 VENT SYSTEM PRESSURIZATION AND THRUST LOADS FOR v

F DBA EVENT 1

A, m F v /1 t

V F 5

A F e il _

F2 #

y E4 'S 'I S s - -

U\ k ,

3 F 5

'S Key Diagram Time During Maximum Component Force Magnitude (kips)

DBA Event (sec) F y(2) F 2

F F F 3 4 5 Pool Swell 0.0 to 1.5 50.6 137.4 20.0 20.0 4.1 Condensation oscillation 46.4 126.2 16.7 17.3 3.6 5.0 to 35.0 Chugging 19.3 5.0 3.3 0.6 35.0 to 65.0 6.6 Notes:

1. Loads shown include the effects of the DBA internal pressures in Figure 3-2.2-3.
2. Values shown are equal to product of penetration unreacted area and DBA internal pressure.

O DET-04-028-3 Revision 0 3-2.58 nutggh

Table 3-2.2-4 POOL SWELL IMPACT LOADS FOR VENT LINE E vent P***- - - - - - .

\ Line

\ \$ e

\ \s b\ _

W g P - - - - - ~

d- i s - C s

\ $ I

, V %.. \ g e

\

/g ls e- T-+3

/ \ Maximum '

' \

Pool Height '

tg t max Time Key Diagram Pressure Transient Time (msec) Pressure (psi)

Segment Number Impact Maximum Pool Impact Impact (t y) Duration (T) Height (t ,,x) (P ) Drag (P }

d l 0.00 0.00 0.00 0.00 0.00 2 0.00 0.00 0.00 0.00 0.00 3 604.00 25.00 890.00 20.85 2.13 4 750.00 73.00 890.00 6.00 1.31 5 850.00 40.00 890.00 0.78 0.00 Notes:

1. For structure geometry, see Figure 3-2,1-8.
2. Pressures shown are applied to vertical projected areas in a direction normal to vent line surface.
3. Loads are symmetric with respect to vertical centerline of vent line.

O

'V DET-04-028-3 Revision 0 3-2.59 nutggh

Table 3-2.2-5 POOL SWELL IMPACT LOADS FOR OTHER VENT SYSTEM COMPONENTS h p ._ _ . P ___ _ _

0 3

$ a e :w j p --- . _ _ _ r p

.--T9 '

Tu e

{

t t i max i max Time Time cylindrical Structures Plat structures PRESSURE TRANSIENTS gg) Time (msec) Pressure (psi)

Segment Item Impact Number Arrival Du ion Maximum Pool Impact Drag (t )

t Height (tmax) I max) (Pd)

DOWNCOMER BRACING - NON VENT BAY 1 475.00 0.50 890.00 81.06 2" ) 9.26 Rod 2 476.00 0.50 890.00 75.78 8.41 3 477.00 0.50 890.00 72.36 7.91 p 1 461.00 0.14 890.00 33.52 33.52 Plates 1 470.00 0.14 890.00 25.93 25.93 1 477.00 2.10 890.00 20.75 2.85 2 510.00 1.60 890.00 38.70 2.76 3 N/A N/A N/A N/A N/A DOWNCOMER BRACING - VENT BAY p 1 478.00 0.16 890.00 18.06 18.06 1 484.00 2.90 890.00 11.59 1.78 4' D 2 N/A N/A N/A N/A N/A Pipe 3 N/A N/A N/A N/A N/A VACUUM BREAKER By g 1 650.00 30.10 890.00 4.95 1.46 Notes:

1. Segment numbers represent nodalization of structures for loads calculations.
2. For structure geometry see Figures 3-2.1-10 through 3-2.1-12,
3. Pressures shown are applied to vertical projected areas in direction nomal to strue'"re.
4. Loads are symmetric with respect to vertical centerline of vent header.
5. Pool swell impact loads do not act en v:cuum breaker succorts.

DET-04-028-3 Revision 0 3-2.60 E)th,hM

Table 3-2.2-6

/ VENT SYSTEM FROTH IMPINGEMENT AND FALLBACK LOADS k]J Up a UP 4 8 80.0 a, g

- - ,_ 100.0 a_

p,____ , p,- --=

a E  :

tg U tg Time (msec) p ffb Region I Transient Down

' ~

Time (msec)

Region II Transient DOWNCOfiER BRACING REGION I FROTH (msec, psi) g Q) Non-Vent Bay Vent Bay Number Impact- Froth Impact Froth Time (t4) PressurefPF Time (til Pressure (Pa' 1 365.00 2.679 N/A N/A 2 368.00 2.656 N/A N/A 3 370.00 2.629 N/A N/A Rin 1 374.00 3.494 379.00 1.966

  • 1 376.00 2.770 N/A N/A 1 371.00 2.204 385.00 2.505 Pi e 2 374.00 2.301 381.00 2.260 3 376.00 2.199 380.00 2.057 VACUUM BREAKER AND SUPPORTS FROTH (msec, pai)

Segmen(l) Region I Region II Item Number Impact Froth Impact Froth Fallback Time (t1) Pressure (Pf Time (t i) Pressure (PAPr=* e M Pr &

{' r 1 400.00 0.829 N/A N/A N/A Nozzle 1 400.00 1.481 N/A N/A N/A 1 384.00 0.993 N/A N/A N/A Support 2 380.00 1.077 663.00 .130 N/A Beam 3 376.00 1.103 565.00 .605 N/A 4 372.00 1.099 513.00 1.041 0.065 Notest

1. Segment numbers represent nodalization of structures for loads calculations.
2. For structure geometry see Figures 3-2.l-10 through 3-2.1-12.
3. Pressures shown are applied to vertical projected areas in direction normal to structure.
4. Loads are symmetric with respect to vertical centerline of vent header.

l DET-04-028-3 l Revision 0 3-2.61 l nutech--

l

Table 3-2.2-7 VENT SYSTEM POOL FALLBACK LOADS h Up max t end 8

a P

fb - - - - - - - - -

Down Time Pressure Transient segment Time (msec) Fallback Item Pressure (P pfg Nu.nber Arrival End of Fallback (tend; (psi)

(tmax)

DOWNCOMER BRACING - NON-VENT BAY l 890.00 1165.00 0.38 2" Q 2 890.00 1158.00 0.15 Rod 3 890.00 1124.00 0.12 Ring 1 890.00 1166.00 3.11 0 Plates 1 890.00 1132.00 2.54 1 890.00 1110.00 0.19 4,, 4 Pipe 2 890.00 991.00 0.14 3 N/A N/A N/A DOWNCOMER BRACING - VENT BAY p 1 890.00 1075.00 1.76 1 890.00 1076.00 0.14 4" &

Pipe 2 N/A N/A N/A 3 N/A N/A N/A Notes:

1. Segment numbers represent nodalization of structures for load calculations.
2. For structure geometry see Figures 3-2.1-11 and 3-2.1-12.
3. Pressures shown are applied to vertical projected areas in direction normal to structure.
4. Loads are s3 vietric with respect to vertical centerline of vent header.

nutsch.

~

Ii~

Revision 0 3-2.62 ini=usen

Table 3-2.2-8 DOWNCOMER LOCA AIR CLEARING SUBMERGED STRUCTURE LOAD DISTRIBUTION g VB EM bN

.- C? _

C3"#E fr-A l -- ! --

l l-j1 l Sym.

Elevation View-Downcomers E VB P S E WS X P P

% x x x x

/ >

Section A-A O

Pressure Magnituae (psi)

Item Segment Number p p x .y 1 -0.09 -0.44 2 -0.25 -1.22 1 -0.38 0.31 2 -1.05 0.87 1 -0.90 -0.56 C 2 -2.61 -1.57 Downcomer 1 -0.75 0.46 2 -2.20 1.28 1 0.00 -0.29 2 0.00 -0.81 1 0.00 0.27 l l F 2 0.00 0.75

~

Note:

1. Loads shown include DLF's of 2.0.

DET-04-028-3 3-2.63 j Revision 0

Table 3-2.2-9 SUPPORT COLUMN LOCA AIR CLEARING SUBMERGED STRUCTURE LOAD DISTRIBUTION E VH Outside M N Inside s ,

t7 y ir 7

2 2 3 3 ~ ?x

Px, ,

4- 4 A A i Pz P g 6

7 7 8 8 Section A-A 9 9 10 , in 11 11 12 12 13 13]

T i O Elevation View - Mitered Joint Pressure Magnitude (psi) g Number Inside Column Outside Column Py P Py P 1 -0.19 0.18 -0.03 0.16 2 -0.60 0.60 -0 .27 0.49 3 -1.09 1.15 -0 .43 0 .83 4 -1.62 1.78 -0.56 1.15 5 -1.86 2.08 -0.67 1.37 6 -1.88 2.08 -0.74 1.38 7 -1.55 1.63 -0.81 1.19 8 -1.10 1.01 -0 .84 0.88 9 -0.68 0.51 -0.85 0.56 10 -0.41 0.12 -0.84 0.27 11 -0.22 -0.19 -0.80 0.07 12 -0 .12 -0.29 -0.76 -0.07 13 -0.09 -0.44 -0.92 -0 .18 14 -0.08 -0.58 -1.12 -0.27 Note:

1. Loads shown include DLF's of 2.0 DET-04-028-3 Revision 0 3-3.64 NO

Table 3-2.2-10 IBA CONDENSATION OSCILLATION Om DOWNCOMER LOADS t (

l l

+

h F" g yF '4: yF N "

N / d A

'h' s

Uniform Pressure Differential Pressure O

Downcomer Load Amplitudes (l)

Frequency Interval (Hz) Uniform (Fu) Differential (F dI12)

Pressure (psi) Force (lb) Pressure (psi) Force (lb) 6.0 - 10.0 1.10 241.75 0.20 43.95 12.0 - 20.0 0.80 175.82 0.20 l 43.95 18.0 - 30.0 0.20 43.95 0.20 43.95 Notes:

1. Effects of uniform and differential pressures summed to obtain total load.
2. See Figure 3-2.2-9 for downcomer differential pressure load distributions.

Cs DET-04-028-3

\_) Revision 0 3-2.65 nutggh

Table 3-2.2-11 DBA CONDENSATION OSCILLATION DOWNCOMER LOADS l

l 1

/

+

F # d u% # u 4

Uniform Pressure Differential Pressure O

Downcomer Load Amplitudes (1)

Frequency Interval (H2) Uniform (Fu) Differential (Fdf Pressure (psi: Force (lb) Pressure (psi) Force (lb) 4.0 - 8.0 3.60 791.18 2.85 626.35 8.0 - 16.0 1.30 285.70 2.60 571.41 l 12.0 - 24.0 0.60 131.86 1.20 263.73 l Notes:

1. Effects of uniform and differential pressures summed to obtain total load.
2. See Figure 3-2.2- 9 for downcomer differential pressure load distribution.

O DET-04-028-3 3-2.66 Revision 0 nutggh

(^h G

Table 3-2. 2- 12 IBA AND DBA CONDENSATION OSCILLATION VENT SYSTEM INTERNAL PRESSURES Component Load Load Characteristics Vent Line Vent Header IBA DBA IBA DBA Single Single Single Single Type Harmonic Harmonic Harmonic Harmonic Magni ude 2.5 1 2.5 1 2.5 1 2.5

(~)h

(_ Distribution Uniform Uniform Uniform Uniform Frequency Range (Hz) 6 - 10 4-8 6 - 10 4-8 Notes:

1. Downcomer CO internal oressure loads are included in loads shown in Tables 3-2.2-10 and 3-2.2-11.
2. Loads shown act in addition to vent system internal pressures in Figures 3-2.2-2 and 3-2.2-3.
3. Additional static internal pressure of 1.5 psi applied to the entire vent system to account for nominal submergence of downcomers.

I

/^,

(_/

DET-04-028-3 i

Revision 0 3-2.67 nutggb 1 1

Table 3-2.2-13 SUPPORT COLUMN DBA CONDENSATION OSCILLATION SUBMERGED STRUCTURE LOAD DISTRIBUTION g vn outside Inside

___ vi 1 i 1

+ 1 , o ~o -

A 1 d A p p 5

_.5 p p, E. fL

-.2_ 7 Section A-A 9_ 2.

.lIL. e l.Q 11 l.L

.12_ 1.2 11 11 W i W Elevation View-Mitered Joint Pressure Magnitude (psi)

O Segment Number Inside Column Outside Column Px Pz Px Pg 1 5.90 -5.05 34.95 -5.65 2 17.38 -15.08 50.53 -12.84 3 28.01 -24.36 54.76 -18.28 4 35.19 -30.56 53.38 -21.51 5 33.54 -28.91 49.80 -22.17 6 29.41 -24.99 45.42 -20.51 7 23.26 -19.24 40.97 -17.51 8 17.66 -13.98 36.99 -14.21 9 13.48 -10.00 33.49 -11.24 10 10.67 -7.24 30.53 -8.82 11 9.04 -5.39 27.62 -6.91 12 8.15 -4.19 25.28 -5.47 13 11.93 -5.31 36.31 -6.87 14 17.74 -7.27 52.14 9.29 Note:

O

1. Loads shown include PSI effects and DLF's.

DET-04-028-3 0 ,

Revision 0 3-2.68

Table 3-2,2-14 MAXIMUM DOWNCOMER CHUGGING LOAD MAGNITUDE DETERMINATION Maximum Chugging Load for Single Downcomer FSTF Maximum Load Magnitude: P i =3.046 kips Tied Downcomer Frequency: fy =2.9 Hz Pulse Duration: t d- 0.003 sec.

Dynamic Load Factor: DLF y = Uf t =0.027 yd Fermi 2 Downcomer Frequency: f=12.4 Hz Dynamic Load Factor: DLF=nft =0.ll7 d

Maximum Load Magnitude (In any direction) :

P =P y(D ) = (3. 04 6) (4. 276) =13. 02 kips max D Note:

1. See Figure 3-2.4-6 for Fermi downcomer frequency determination.

DET-04-028-3

( Revision 0 3-2.69 nutggh

Table 3-2.2-15 MULTIPLE DOWNCOMER CHUGGING LOAD MAGNITUDE DETERMINATION O

E

.k '

x

~ (

e 10.0= \

c I B _\

g 2L m x c

5.0= \ \

e  % %_ _

0

.a .

b '

, 0. 0 4 1 20 40 60 80 Number of Downcomers Leaded Chugging Loads for Multiple Downcomers (kips)

O Number of Number of Probability FSTF Load Fermi Load Downcomers Chuas of Exceedance Per Downcomer Per Downcomer 5 344 2.91 x 10 -3 1.77 7.57 10 688 -3 1.45 x 10 1.26 5.39 20 1375 -4 7.27 x 10 0.91 3.89 40 -4 2751 3.64 x 10 0.68 2.91 80 5502 1.92 x 10 ~4 0.57 2.44 FSTF Chugging duration: T c = 512 sec Number of downcomers:,nde, = 8 Number of chugs: N ei = 313 Fermi Chugging duration: Tc = 900 sec Number of downcomers: n de = 2 to 80 Number of chugs: N e = "C' xT cxn n de Probability of exceedancc: P,x e* = 1

/N c O

DET-04-028-3 Revision 0 3-2.70 DUkp_Qb

l l

l Table 3-2.2-16 k_) CHUGGING LATERAL LOADS FOR MULTIPLE DOWNCOMERS-MAXIMUM OVERALL EFFECTS Number of (1)

N r Downcomers Description / Distribution Magnitude Loaded (kips)

All downcomers, parallel 1 80 to MC plane, same direction, maximize 2.44 overall lateral load All downcomers, parallel to one VL, same 2 80 direction, maximize 2.44 ove all lateral load All downcomers, parallel 3 80 to VH, same direction, 2.44 maximize VL bending

() 4 80 All downcomers Perpendicular to VH' same direction, maximize 2.44 VH torque Downcomers centered on 5 10 ne VL, perpendicular t VH, opposing directions, 5.39 maximize VL bendino Downcomers centered on one VL, perpendicular to 6 10 VH, same directions, 5.39 maximize VL axial loads All downcomers between two VL's, perpendicular

) 7 10 to VH, same direction 5.39 l

maximize VH bending NVB downcomers near 8-10 4 miter, parallel to VH' permutate directions, 8.51 maximize DC bracing loads

, (m Note:

l

1. Magnitudes obtained from Table 3-2.2-15.

DET-04-028-3 3-2.71 l1(jk Revision 0

Table 3-2.2-17 CHUGGING LATERAL LOADS FOR TWO DOWNCOMERS LOADED-MAXIMIZE LOCAL EFFECTS E VL em v

v A 'S Y P '3 gp f J Q VU Pn P g' #

P -* 10 P 6

4 4 P

2 Key Diagram-Plan View Downcomer Load Cases for Maximum Local Effects e

Case Active II' Magnitude ( 2) Case Activh Magnitude (2)

Number Loads (p g) (kips) Number Loads (Pg ) (kips) 11 +Pi, -P2 11.16 17 -P9,+P lo 11.16 12 +Py, +P2 11.16 18 +P9,+P l o 11.16 13 -P7, +P8 11.16 19 +P5,-P6 11.16 14 +P 7, +P8 11.16 20 +P5,+P6 11.16 15 +P3, -P4 11.16 21 -P11,+P12 11.16 16 +P3, +P4 11.16 22 +P11 , +P12 11.16 l Notes:

1. Signs designate direction.
2. Magnitudes obtained from Table 3-2.2-15.

O DET-04-028-3 Revision 0 3-2.72 g

\

,_ Table 3-2.2-18 LOAD REVERSAL HISTOGRAM FOR CHUGGING Q ,

DOWNCOMER LATMAL LOAD FATIGUE EVALUATION N

( s JL 337.So 00 22.50 3150 8 1 450 7 2 s 292.5 0 6 3 67.50 5 4

's ' 270 0 900 + E 4 j"/ ' 5

[A

}.

A 247.5 0 3 6 112.50 2250 1 8 1350 202.5 0

  • 1800 Elevation View Section A-A

'.<tY DIAGPAM Percen* of Angular Sector Load Reversals (cyclesh Maximum LoadRang 1 2 '3 ~4 5 6 7 8 5- 10 4706 2573 2839 3076 3168 2673 2563 4629 10 - 15 g 2696 1206 i 1100 1104 1096 1052 1163 2545 15 - 20 1399 727 653 572 709 708 679 1278 20 'I5 676 419 '. 452 37I 370 398 368 621 25 - 30 380 250 252 225 192 255 197 334 30 - 35 209 187 139 121 97 114 162 208 35 - 40 157 62 e4 86 62 60 90 150 40 - 45 113 53 28 39' 48 44 58 86 45 - 50 "63, 33 32 26 18 23 33 67 50 - 55 65 26' '

14 11 . 9 7 16 40 55 -- 60 51 26 11 '5 11 11 23 28 60 65 '

'44 9 2 ' i 0 5 9 26 65 - 70' 32 '

16 7 5 0' 2 9 21 l 70 - 75 12 9 11 5 '

O 4 7 i 19 75 - 90 26 4 2 0 2 - 4 7 18 l 80 - 85 7 5 + 2 ,0 0 0 0 12 8%- 90 4 li . 0 0 0 0 $ 11 90 - 95. 7 4 0 1 0 2 0 0 9 95 - 100 2 9- O' 'i n n 7 4 7 Notest =

1. Values shown are for chugging duration of 900 sec.
2. The maximum single downcomer' load magnitude range \ used for fatigue is 3.936 x 4.276 = 16.8 kips ,f see Table '3-2.2-14) .

'Ci DET-04-028-3 T~ ' '

Revision 0 ' ' 3 - 2 . 7 3' '

4, -

nutggh p ,y S

ys' t

1 l

/

Table 3-2.2-19 CHUGGING VENT SYSTEM INTERNAL PRESSURES y  : Load Type Component Load Magnitude (psi)

Description Vent Vent

, IUumber Description Downcomer Line Header Gross Vent .

Systan Pressure Transient pressure.

1 -+ 2.5 + 2.5 + 5.O i

Oscillation Unifona dshhtion. - -

Acoustic Vent Single hannanic in 2 Systen Pressure 6.9 to 9.5 Hz range. + 3.0

-+ 2.5 + 3.5 Oscillation Uniform distribution. - -

Acoustic S~ le harmonic in Downcomer 40 to 50.0 Hz 3 Pressure N/A range. Uniform N/A -+ 13.0

_'_ Oscillation listribution.

4

( '

{_ Loading Information i l'-

E

'/1 /\ /k- 1. Downcomer loads shown

/ _ \

/ $

/ ) _ used for hoop stress 8 0. ---/ -

/ t / calculations only.

5 -rgf-"

'21

/ \ / g 2. Loads act in addition to 8 -2.-

o.

i l V I/ \ internal pressure loads

_'ZCyi shown in Figure s 3-2.2-2 hM I i ' and 3-2.2-3.

-4. i a 4 a 0.0 1.0 2.0 3.0 4.0 Time (sec)

Forcing Function for Load Type 1 1

1 <

O

.> ET-04-02h-3

. cs 4 /Peyision 0 3-2.74 11Ut a..c . 19

.s .

. . .. ,9 - <,

.l ,_t t'l

Table 3-2.2-20 SUPPORT COLUMN PRE-CHUG SUBMERGED STRUCTURE LOAD DISTRIBUTION g VH.

Outsid, Inside 7

1 , 1 9 2 P P 3

g j x1 ) x A d- S- A <

p i Pg Pg

_.2 _Z.,_ Section A-A 8 8

._2._ 4 10 , g 11 11 12 12 13 11 W i W Elevation View 'ji tered Joint Pressure Magnitude (psi)

Se ent Inside Column Outside Column P P P x x P .,

1 0.26 -0.19 0.34 -0.17 2 0.78 -0.59 0.59 -0.43 3 1.25 -0.98 0.74 -0.62 4 1.56 -1.23 0.83 -0.72 5 1.47 -1.07 0.89 -0.69 6 1.25 -0.74 0.92 -0.54 7 0.93 -0.34 0.93 -0.34 8 0.66 -0.03 0.92 -0.14 9 0.46 -0.18 0.89 -0.10 10 0.33 -0.30 0.85 -0.20 11 0.26 -0.35 0.80 -0.25 12 0.22 -0.37 0.74 -0.28 13 0.32 -0.58 1.08 -0.45 14 0.47 -0.86 1.55 -0.67 Note:

1. Loads shown include FSI effects and DLF's, g

DET-04-028-3 3-2.75 Revision 0

E Table 3-2.2-21 SUPPORT COLUliN POST-CHUG SUBMERGED STRUCTURE LOAD DISTRIBUTION O g VH Outside Inside 7 -

1 1 2 2 I

h h A A 5 5 Pz Pg 6 8 6

7 7 8 8 Section A-A 9 9 12_ i J.1 11 11 12 12 13 13 I i , 1 1 .1 l l

Elevated View-Mitered Joint Pressure Magnitude (psi)

O Segment Number Inside Column Outside Column Px Pz Px Pz 1 17.05 -3.07 11.20 -2.44 2 50.77 -9.23 22.92 -6.53 3 81.49 -14.99 31.23 -9.89 4 102.44 -18.76 36.41 -11.98 5 98.63 -17.49 38.60 -12.44 6 88.70 -14.63 38.16 -11.39 7 72.54 -10.66 35.85 -9.48 I

8 56.83 -7.14 32.60 -7.40 9 44.18 -4.57 29.07 -5.57 10 34.71 -2.87 25.70 -4.13 11 27.81 -1.80 22.57 -3.06 12 22.85 -1.14 19.96 -2,29 13 30.01 -1.17 27.74 -2.75 14 41.67 -1.44 39.28 -3.64 Note:

O

1. Loads shown include PSI ef fects and DLF's.

DET-04-028-3 3-2.76 nutggh Revision 0

Table 3-2.2-22 e DOWNCOMER SRV DISCHARGE SUBMERGED STRUCTURE LOAD DISTRIBUTION

(

e va sm .pnv8 b -

E, A l A Sym.

Elevation View-Downcomers VB P

W aP NVB p p x P P i 6 Q ~ cz, ,

Section A-A Segment ssure Magn W e (psU Item Number p (1) p (1)

X Y A 1 1.55 -0.08 2 2.69 -0.27 1 1.57 0.27 2 2.69 0.53 C 1 -0.17 -2.30 2 -0.37 -4.19 Downcomer 1 -0.92 2.06 D

2 -1.59 3.76 1 0.70 0.10 2 1.58 -0.29 1 1.22 0.12 F 2 2.64 0.29 Note:

1. Loads in X and Y direction include DLF's of 2.0 and 3.0, respectively.

{)h

~

DET-04-028-3 Revision 0 3-2.77 nutggb

Table 3-2.2-23 1

SUPPORT COLUMN SRV SUBMERGED STRUCTURE LOAD DISTRIBUTION CW outside Inside 1 i 1 "x Px A 1 4 A p 5_

l pz pz 6 fi.

7 7 SECTION A-A A o 1.a_ n LO.

.LL 11

.12_ 12 rb, , i ll i

@ l D Elevation View-Mitered Joint Pressure Magnitude (psi)

Number Inside Column Outside Column Px Pz Px Pz 1 0.12 0.21 0.12 0.21 2 0.12 0.21 0.12 0.21 3 0.28 0.45 0.28 0.45 4 0.28 0.45 0.28 0.45 5 0.33 0.50 0.50 0.33 6 0.39 0.54 0.39 0.54 7 0.46 0.52 0.46 0.52 8 0.46 0.52 0.46 0.52 9 0.49 0.44 0.49 0.44 10 0.49 0.44 0.49 0.44 11 0.25 0.80 0.25 0.80 12 0.25 0.80 0.25 0.80 13 0.46 1.13 0.46 1.13 14 0.58 1.50 0.58 1.50 Note:

g

1. Loads shown include DLF of 3.0.

DET-04-028-3 gk Revision 0 3-2.78

i l

l P = 0.0 psi O o V

30.

Drywell/ Vent System Absolute Pressure Udp 1'

^

tn 2 0 . -  :

[

a LO /

8  ;

l O /

4 1 0 y A /

" 10. ~ /

O s y '

/ Vent System / Suppression m e Chamber AP f

/ /

r f s-2 ...->.A - '

. F.

w -u--e- ~

1.

1.0 10.0 100.0 1000.0 10000.0 Time (sec)

_J Time (sec) Pressure (psig)

Event Pressure Description Designation t t P min min min max max Instant of Break to Onset Py O. 300. 0.750 0 .175 11.7 1.7 of Chuqqing Onset of Chugging t P 300. 600. 11.7 1.7 20.9 1.5 Initiation of 2 Anc; Initiation of ADS to RPV P 600. 1200, 20.9 1.5 24.2 1.8 3

Depressurizaticr l Pigure 3-2.2-1 VENT SYSTEM INTERNAL PRESSURES FOR SBA EVENT (3

'w/ DET-04-028-3 Revision 0 3-2.79 nutggh

P g

= 0.0 psi g l

40.

l l

& 1

/

Drywell/ Vent System /

30.= Absolute Pressure -i /

3d l \ /

\ /

E. t / '

- j,-- 1 e 20.= j- --

i

$ /

en f

$ /

$ = /ent System / Suppression -

10.

1

/ [ Chamber AP \ -

f \

t.6 % .._ ,_.

--.... . . .... . . . . . . . . . . . . . . . . . . . < . . . . . . . . . . . _ . - i 0.- i i 1.0 10.0 100.0 1000.0 Time (sec) g Event Pressure Time (sec) Pressure (psig)

Description Designation t t P AP P AP min max min min max max Instant of Break to Onset of Py O. 5. 0.750 0.175 3.0 1.5 CD arti Qujgin)

Cruu)t of CD ani O u rJinJ to P 5. 300. 3.0 1.5 21.7 1.4 2

Initiation of ADG Initiatico of ME to PW P 3

300. 500. 21.7 1.4 34.7 2.0 Depressurization Figure 3-2.2-2 VENT SYSTEM INTERNAL P9ESSURES FOR IBA EVENT g DET-04-028-3 Revision 0 3-2.80

Pg = 0.0 psi 60.

r A

es 'N N-a / N, g g 40.-

c -

g Drywell/ Vent System Absolute Pressure

- f\ N N u

p h.

a m_--

r m

. ' ' ~ -

$ fl --. . ........ . ......... . - - ,,

20. =

t 7 s. ,

Vent System / Suppression ~ }, .,

Chamber AP . ..,

D. I c 0.0 10.0 20.0 30.0 Time (sec)

Time (sec) Pressure (psig)

Event Pressure Description Designation t 0 0 min max min min max max Instant of Break to huninaticn of P 0.0 1.5 0.150 0 .175 39.6 31.6 Pool Swell 1 Tenninaticn of Pool Swll to P 2

1.5 5.0 39.6 31.6 48.0 32.5 Onset of CD Chset of CD to P 5.0 35.0 28.0 4.1 45.0 29. 0 Onset of C2iugging 3 Onset of Chtxjging to RPV P 35.0 65.0 28.0 4.1 28.0 4.1 h 4

t Depressurizaticn i l Note:

1. DBA vent system internal pressure loads are included in vent system pressurization and thrust loads shown in Table 3-2.2-3.

Figure 3-2.2-3 VENT SYSTEM INTERNAL PRESSURES FOR DBA EVENT DET-04-028-3 Revision 0 3-2.81 O

l l

T = 70 F 1 O

400. ~ hl g __

Drywell/ Vent System o

  • Component Temp. (T C) \=

e s 9 __..__

o a

m

$200.

n.

E o

Ed Vent System External ,,,.

Component Temp. (Tp) \y 100. -_,<,

__ _. _____. w.<r-

80. i  ; 3 1.0 10.0 100.0 1000.0 10000.0 Time (sec)

Note:

1. See Table 3-2.2-2 for additional SBA event temperatures.

Time (sec) Temperature (UF)

Evt.nt Temperature T T T T Description Designation t t E min max min min max max Instant of Break to Chset of Ty O. 300. 135.0 95.0 270.0 98.0 Chugging Chset of Chtsging to Initiaticn of T 2

300. 600. 270.0 98.0 270.0 103.0 ADS Initiation of ADS to RPV T 3

0. 1200. 270.0 103.0 270.0 134.0 Depressurization Figure 3-2.2-4 VENT SYSTEM TEMPERATURES FOR SBA EVENT DET-04-028-3 3-2.82 nutp_q=h=

Revision 0

l l

T o = 70 F l

400.

O 300.

E -

Drywell/ Vent System '

/

O Component Temp. (TC) \ -

o i u

o

% 200.-

u ,

c) c.

E Vent System External .-

$ Component, Temp. (TE) \y /

, i

~~~ ~~

10 0 .= . . . . . . . ....... . . ... ... j..... . . . . . . . . .... .. . . . .1L . , . .~ - -

80. i u i 1.0 10.0 100.0 1000.0 Time (sec) t D

'(.

Event Temperature Time (sec) Temperature ( F)

Description Designation T T Instant of Break to Cnset of CO and Ty O. 5. 135.0 95.0 228.0 95.0 Chuquing onset of CD and Chugging to T 5. 300. 228.0 95.0 262.0 112.0 2

Initiation of ADS Initiation of ADS to RPV T 3

300. 500. 262.0 112.0 280.0 173.0 Depressurization Figure 3-2.2-5 VENT SYSTEM TEMPERATURES FOR IBA EVENT n'

DET-04-028-3

. . 3-2.83 Revision 0 nuttgb

Tg = 70 F 400. --

I Drywell/ Vent System Component Temp. (TC) \

E 300. =

ov

\

g o -F I

h E

f C 200. .

e Go E

y __ Vent System External Component Temp. (TEI \ '

l0 0. _ . y

..---" ^"------ - -

60.

li l 0.0 10.0 20.0 30.0 Time (sec) 9 Time (sec) Temperature ( F)

Event Temperature Description Designation t T T T T min max C min E .

min C

max E max l Instant of Break

to Termination of T 1

0.0 1.5 135.0 70.0 276.0 73.5 t Pool Swell l Terminaticn of Pool Swell to T 1.5 5.0 276.0 73.5 292.0 78.8 Onset of CO 2 Onset of 00 to Onset of Chugging T 3

5.0 35.0 292.0 78.8 270.0 109.0 l

Onset of 01ugging to RPV T 4

35.0 65.0 270.0 109.0 270.0 109.0 Depressurizaticn Figure 3-2.2-6 VENT SYSTEM TEMPERATURES FOR DBA EVENT DET- 0 4-02 8-3 RevAsion 0 3-2.84 mt h

=

O, t.s1 , ,

l

+ +

r 4 \

A A 3 34 3 2

O 2 50 0 Section A-A max Elevation View Pressure Distribution P max = 8.0 psi, tmax = 890. msec Load Information Downcomer Segment Impact Time O Pair Location Number ti (msec) b 1 343.00 P,,, Vent Bay 2 410.00 ll 3 459.00 m

0 Non-Vent 1 343.00 m

Bay Near 2 406.00 Miter 3 452.00 1 337.00 Midcylinder 2 tg t 402.00 max Non-Vent Bay 3 450.00 Time Pressure Transient i

! Note:

1. Pressures shown are applied in a direction normal to downcomers surface.

Figure 3-2.2-7 DOWNCOMER POOL SWELL IMPACT LOADS DET-04-028-3 Revision 0 3-2.85 nutggh

VB NVB

_ L _

b( k o -

t Z. (F(t) (

_ F (t) _

Deflecto 0.0 0.5 1.0 Developed View Section KEY DIAGRAM s

I 4000. =

==Z/L=1.0 2 /4 i i u

N e

j '/ ,I Z/L=0.5 d / -

'/ A

/ '

,- Z /L= 0 . 0 g 2000.

u

/ ,

,- \,

/ .

~;' ' ,

&* { ,

I

,i E-- ............

3,p j , (- ---.... . ' ~,,,g A -,g

,' %w 0  ;

n 400.0 500.0 600.0 Time (msec)

Note:

1. Loads at discrete locations along deflector obtained by linear interpolation.

Figure 3-2.2-8 POOL SWELL IMPACT LOADS FOR VENT HEADER DEFLECTORS AT DET-04-028-3 SELECTED LOCATIONS Revision 0 3-2.86

S .VL ~ E VL Q \ C

\ \ '

,b '

, ~n '

\ \

'U 'U l

Case 1 Case 2 g VL g VL o o r O , ,

, sn '

, sn '

'U

\

'U

\

i.

Case 3 Case 4 Notes:

1. See Table 3-2.2-10 for IBA pressure amplitudes and frequencies.
2. See Table 3-2.2-11 for DBA pressure amplitudes and frequencies..
3. Four additional cases with pressures in downcomers-opposite those shown are also considered.

l Figure 3-2.2-9 I

IBA AND DBA CONDENSATION OSCILLATION DOWNCOMER DIFFERENTIAL PRESSURE LOAD DISTRIBUTION l

DET-04-028-3' '

Revision 0 3-2.87 g

To G Drywell

+---

G

[j d-A B ce ~ /

\

l F

Key Diagram Loading Inforraation Profile Pool Acceleration (ft/sec )

2 A 10.0 B 20.0 C 30.0 D 40.0 E 50.0 F 60.0 Pool accelerations due to harmon-ic application of torus shell pressures shown in Figure 2-2.2-10 at a suppression chamber frequency of 20.39hz.

Figure 3-2,2-10 POOL ACCELERATION PROFILE FOR DOf1INANT SUPPRESSION CHAMBER FREQUENCY AT MIDCYLINDER LOCATION DET-04-028-3 Revision 0 3-2.88 mt h.

3-2. 2. 2 Load Combinations The load categories and associated load cases for which the vent system is evaluated are presented in Section 3-2. 2.1. The general NUREG-0661 criteria for grouping the respective loads and load categories into event combinations are discussed in Section 1- 3. 2 and i presented in Table 3-2.2-24.

The 27 general event combinations shown in Table 3-2.2-24 are expanded to form a total of 69 specific vent system load combinations for the Normal Operating, SBA, IBA, and DBA events. The specific load combina-tions reflect a greater level of detail than is con-tained in the general event combinations, including distinction between SBA and IBA, distinction between pre-chug and post-chug, and consideration of multiple cases of particular loadings. The total number of vent system load combinations consists of 3 for the Normal Operating event, 18 for the SBA event, 24 for the IBA event, and 24 for the DBA event. Several different sarvice level limits and corresponding sets of allowable stresses are assoc'.ated with these load combinations.

DET-04-028-3 Revision 0 3-2.89 nutg.gb

O Not all of the possible vent system load combinations are evaluated since many are enveloped by others and do not lead to controlling vent system stresses. The en-veloping load combinations are determined by examining the possible vent system load combinations and comparing the respective load cases and allowable stresses. The results of this examination are shown in Table 3-2.2-25, where each enveloping load combination is assigned a number for ease of identification.

The enveloping load combinations are reduced further by examining relative load magnitudes and individual load characteristics to determine which load combinations lead to controlling vent system stresses. The load combinations which have been found to produce control-ling vent system stresses are separated into two groups. The SBA II, IBA I, DBA I, DBA II, and DBA III combinations are used to evalute stresses in all vent system components except those associated with the vent line-SRV piping penetrations. The NOC I, SBA II, IBA I, and DBA III combinations are use to evaluate stresses in the vent line-SRV piping penetrations. An explanation of the logic used to conclude that these are the controlling vent system load combinations is presented DET-04-028-3 Revision 0 3-2.90 nutp_qh

O in the gareereghs waica re11o.. eab1e 3-2.2-2e semmar-izes the controlling load combinations and identifies which load combinations are enveloped by each of the controlling combinations.

Many of the general event combinations shown in Table 3-2.2-24 have the same allowable stresses and are enveloped by others which contain the same or additional load cases. There is no distinction between Service Level A and B conditions for the vent system, since the Service Level A and B allowable stress values are the same.

Many pairs of load combinations contain identical load cases except for seismic loads. One of the load combi-nations in the pair contains OBE loads and has Service Level A or B allowables, while the other contains SSE loads with Service Level C allowables. It is evident from examining the load magnitudes presented in Section 3-2. 2.1 that both the OBE and SSE vertical accslerations are small compared to gravity. As a result, vent system stresses and support column reac-tions due to vertical seismic loads are small compared to those caused by other loads in the load combination.

The horizontal loads for OBE and SSE are less than 50%

p U DET-04-028-3 Revision 0 3-2.91 nutagh

of gravity and also result in small vent system stresses h compared to those caused by other loads in the load combinations, except at the vent line-drywell penetra-tions which provide horizontal support for the vent system. The Service Level C primary stress allowables for the load combinations containing SSE loads are 40 to 80% higher than the Service Level B allowables for the corresponding load combination containing OBE loads. It is apparent, therefore, that the controlling load com-binations for evaluation of vent system components, except the vent line-drywell penetration, are those containing OBE loads and Service Level B allowables.

For the vent line-drywell penetration, evaluation of both OBE and SSE combinations is necessary, since seismic loads are a large contributor to the total lateral load acting on the vent system for which the penetrations provide support.

By applying the above reasoning to the total number of vent system load combinations, a reduced number of enveloping load combinations for each event is obtained.

The resulting vent system load combinations for the Normal Operating , SBA, IBA and DBA events are shown in Table 3-2.2-25, along with the associated service level DET-04-028-3 Revision 0 3-2.92 nutp_qh

l- assignments. For ease of identification, each load combination in each . event is assigned a number. The l reduced number of enveloping load combinations shown in Table 3-2.2-25 consists of 1 for the Normal Operating event, 4 for the SBA event, 5 for the the IBA event, and

( 6 for the DBA event. The load case designations for the loads which make up the combinations are the same as those presented in Section 3-2.2.1.

It is evident from an examination of Table 3-2.2-25 that further reductions in the number of vent system load combinations requiring evaluation are possible. Any of the SBA or IBA combinations envelop the NOC I combina-O tion. ince ther coneein the eeme 1oedines ee the noc 1 combination and in addition, contain condensation oscillation or chugging loads. The NOC I combination does, however, result in local thermal effects in the vent line-SRV piping penetration for the condition when the penetration assembly is cold and the corresponding  !

SRV piping is hot during an SRV discharge. The SBA and 1

IBA combinations, therefore, envelop the NOC I combina-tion for all vent system components except the vent line-SRV piping penetration. The NOC I combination is evaluated for the vent line-SRV piping penetration since it may result in controlling penetration stresses. The O) k DET-04-028-3 Revision 0 3-2.93 nutggh

effects of the NOC I combination are also considered in the vent system fatigue evaluation.

The SBA II combination is the same as the IBA III combi-nation except for negligible differences in internal pressure loads. Thus IBA III can be eliminated from consideration. The SBA II combination envelops the SBA I and IBA II combinations, since the submerged structure loads due to post-chug are more severe than those due to pre-chug. It also follows, from the rea-soning presented earlier for OBE and SSE seismic loads, that the SBA II combination envelops the SBA III, SBA IV, IBA IV, and IBA V combinations, except when the effects of lateral loads on the vent line-drywell pene- 9 tration are evaluated. Similarly, the SBA II combina-tion envelops the DBA V and DBA VI combinations, except that these combinations contain vent system discharge loads which are somewhat larger than the pressure loads for the SBA II combination. This effect is accounted for by substituting the vent system discharge loads which occur during the chugging phase of a DBA event for the SBA II pressure loads when the SBA II load combina-tion is evaluated.

DET-04-028-3 O

Revision 0 3-2.94

@k j i

p

(> By examination of Table 3-2.2-25, it is evident that the load combinations which result in maximum lateral loads on the vent line-drywell penetration are SBA IV, IBA V, and DBA VI. All of these contain SSE loads and chugging downcomer lateral loads which when combined, result in the maximum possible lateral load on the vent system.

i As previously discussed, the SBA II combination envelops the above combinations except for seismic loads. The ef fects of seismic loads are accounted for by substitut-ing SSE loads for OBE loads when evaluating the SBA II combination.

4 The DBA II combination envelops the DBA IV combination, since the SRV discharge loads which occur late in the DBA event have a negligible effect on the vent system.

j The DBA II combination also has more restrictive allow-ables than the DBA IV combination.

The controlling vent system load combinations evaluated in the remaining report sections can now be summarized.

The SBA II, IBA I, DBA I, DBA II, and DBA III combina-tions are evaluated for all vent system components except those associated with the vent line-SRV piping penetration. The DBA I and DBA II combinations do not need to be examined when evaluating the vent line-SRV DET-04-028-3 Revision 0 3-2.95

piping penetration, since they do not contain SRV dis-g charge loads which are a large contributor to loads on the penetration. Thus, the NOC I, SBA II, IBA I and DBA III combinations are evaluated for the vent line-SRV piping penetration. As previously noted, SSE loads and the vent system discharge loads which occur during the chugging phase of the DBA event are conservatively substituted for OBE loads and the SBA pressure loads when evaluating the SBA II load combination.

To ensure that fatigue is not a concern for the vent system over the life of the plant, the combined effects of fatigue due to Normal Operating plus SBA events and Normal Operating plus IBA events are evaluated. The $

relative sequencing and timing of each loading in the SBA, IBA, and DBA events used in this evaluation are shown in Figures 3-2.2-11, 3-2.2-12 and 3-2.2-13. The fatigue ef fects for Normal Operating plus DBA events are enveloped by the Normal Operating plus SBA or IBA events, since the combined effects of SRV discharge loads and other loads for the SBA and IBA events are more severe than those for DBA. Additional information used in the vent system fatigue evaluation is summarized at the bottom of Table 3-2.2-25.

l l

i DET-04-028-3 Revision 0 3-2.96 I nutggh

I i

r l

O 'he ac 't" et a eve == e9"e ci=9 ae cridea i= l the preceding paragraphs envelop those which could ,

actually occur during a IOCA .or SRV discharge event. An l evaluation of these load combinations results in a con-  !

s servative estimate of the vent system response and leads ,

to bounding values of vent system stresses and fatigue effects. .

I i

L l

O l I

1 j

i t

i 1  !

l i

l I

DET-04-028-3 Revision 0 3-2.97 nutagh

- - . . - - . - . - . . --~ . _ - - -, . _ - - - - _ . . - - . - - - - . - . - - - - - . _ _ . - . . . -

Table 3-2.2-24 h MARK I CONTAINMENT EVENT COMBINATIONS

  • su saa e so se say saa.sav.ro Say EQ IRA IRA e EO Isa.say Isa.sav+30 Larthemane Type 0 1 0 5 0 5 0 5 0 5 0 5 0 S 0 5 0 &

1 2 3 4 5 6 7 MMS 8 9 10 11 12 13 14 15 to 17 18 IS 20 21 22 23 24 45 26 27 normal I I I I I I z 3 I z I I I I I I I I I I x I I I x I I E arthetsak e I I I I g I g 3 3 3 3 3 g 3 g g 3 3 SRV Discharge I I I 4 1 g 3 3 x g g g 3 g g LOC A Thermal I I 3 I I 3 g 3 I 3 3 3 3 g 3 3 g g g g 3 g g g LOC A heactions I I I I I 1 3 3 2 3 3 g g I 2 I 3 g 3 3 3 3 3 g I I I 1 2 2 1 I I I 2 2 X X X X X X X X X X X X LOC A Pool 5= ell x I I I I I LOCA Condensation ,

oset11a* tone H A x H A X K H X X X LOCA Chuartne 1 1 I I I I I I I I, 1 I Note:

1. See Section 1-3.2 for additional event combination inf onnation.

DET-04-028-3 Revision 0 3-2 98 nut _

r I

[ Table 3<

CONTROLLING VENT SYSTD l

l Section n n/ Event NOC SBA 3-2.2.1 Volume 3 Load .

...I: I II. III IV :I I Load Combination Number - -

Designation Table 3-2.2-24 Load

2. 14  ; 14'. 15 15 j.14 .

Combination Number

1) Dead Weight .la O OBE 2a 4 = 2 ay i2alse-
2) Seismic SSE 2b 2b
3) Pressure (l) p(2) p ,p 3 E'3 2 P2,P3 2' 3 2 3
3) Temperature 3) .T I4I T2,T3 I2 T 3 2,T3 T 2'T3 T 2I3 E
4) Vent System Discharge
5) Pool Swell
6) Condensation Oscillation 6ai6cl
sg Pre-Chug 7a-7c 7a-7c 7c
7) Chugging Post-Chug l7a;7b 7a,7b

-7d 7d

8) SRV Discharge '8a t
9) Piping Reactions 9ad l
10) Containment Interaction 10ac:

Service Level B- B /B C C (B'! --

Number of Event Occurences II 150' 1 Number of SRV Actuations (9) 2804 50 < > 50 2 51 *>--

i DET-04-028-3 Revision 0 3-2 l '%.

ss

2-25 LOAD COMBINATIONS IBA DBA III IV V .I: II_' _III IV V VI 14 15 15 _1 g . -20; 2 5.- 27 27 27 e la p 2a 2a -2a -

2b 2b J 2b j d 2b

,P -

Py P 3 P2'E3 2' 3 2' 3 1- 3 3 4 4

,T 3 2' 3 2' 3 2' 3

.T y -

LT3 ' IT __

y T 3

T 4

T 4

4a 4 -  : 4a Sa-Se- SS-Se 6b,6d 6b,6d 6f 6f 7c 7a-7c 7a-7c 7a,7b 7a,7b 7a,7b 7d 7d 7d

8a 8a 8J5) 8J5) 8d

> 9a

> 10 a B C C B( 6,7) B I7) C C C C w1

> 25 0 0~ - l' 4 1 nut.ejj

/

_,s. . , . - _ ... _

l A 7,

+

2.s c- y .

'N

. Q.,

^*

W. '

'e , , th e .

, , , %..s. t, ,.-

3 r* ,

e

.h L T  % .

j .

.,, h

  • u.

1 *, ,

3i; s ' s Table 3-2.2-25

- i y .d ,g (Concluded) -

~

~~ ,

G 3

CONTROLLING VENT S?! STEM LOAD COMBINATIONS

r. 4 ,, ,

h t w. ,

  1. , wi \ ,,7 '[ .-

" Notes for Table 3-2.2-25 3  ;('A.1,\g \'

, ,.s 'n ,

1. See Fiqures 3-2,2-1,throug'h 3-2.2-3 for SBA, IBA', and

+ DBA inhernal ' A ure,;galues.

3 . N ,

2. The. range or a al operating internal, pressures is 0.0 to 2.0 psi as specified by the FSARP
3. See Figures 3-2.2-4'through 3-2.2-6 for SBA, IBA, and DBA temperature vp,1ues.

~

q 4..,Th'e' range of normal operating;3emperatures is 50.0

, to 150.Ok F as syepified by the1FSAR. ,See Table 3-2.2-2 for additional normal operating temperatures.

t .

M' The SRV discharge loads which' occur during this phase 5.

p of the DBA eventhave a negl.igible effect on the (j g N vent system.

6'.* j Evaluation of primary-plus-secondary stress range or L  ?', fatigue not required. ,

-- . 7. fhe allowable stress..value for local _ primary me$brane stress at penetrations -dncreased by'l.L

. 1. s Ng >

,< s , ,A e ,

,; 8,* The number of s seismic' load cycles used for fati$up'is 1000.

A n \

3i.g ~

g g

9. The values shoWh are conscevative estimat93 of the number
c of actuations expected for 'u BWR 4 plant witn a reactor F ,

sizo of 251. y -

a{ t

'r .,

s  ; s ...

fm  %

(:m. So, 2 t

-' r t .

e "g ,, [ .,f" # ,'\ r [

'^

w.J e *P{(j ,., ~,

4 4 ',jg ,

~ 11. ga j. . i O

. 4.

. gJ, ,

f

s. . ,

t ft, .

s _n

.' t s

J . ,

n , s, m

-  %, 9 >

[ .;\

4w h J_n l-

.a - - ' SET-04-028-3 .' y a /

l'~~ ,4 ' Revision 0 . 3-2.100 p Qd

% :-it -

{ ,

e' , . ,

Y 'l . R  ? }

q, \_ . m-

n 6 . .

+. w- -

& .K -

LL .

l l

1 Tablo 3-2.2-26 ENVELOPING LOGIC FOR CONTROLLING VENT SYSTEM LOAD COMBINATIONS Condition / Event NOC SBA IBA DBA Table 3-?.2-24 Enveloping Load combinations 2 14 14 15 15 14 14 14 15 15 18 20 25 27 27 27 4-6, 4-6, 3, 7, 3,7, 4-6, 4-6, 4-6 , 3,7 , 3,7, 19, 21, 21, 21, Table 3-2.2-24 I,oad 1 8, 8, 9, 9, 8, 8, 8, 9, 9, 16 17 22, 23, 23, 23, Combinations Enveloped 10 13 13 10 10- 13 13 24 26 26 26 12 12 12 12 12 I I II III I II III I I Combi n De ation SDA II X X X X X X X X X X Vent IBA I X y System o Components y$ and DBA I

  • 3 Supports DDA II X
    • DBA III yy MOC I oM Vent Line-Uj SRV Piping SBA II X X X X X X X X X 0 Penetration IBA I DBA III X X X NOTE:
1. SSE loads and DBA pressurization and thrust loads are substituted for OBE loads and SBA II internal pressure loads when evaluating the SBA II load combination.

DET-04-028-3 Revision 0 3-2.101 nut _e_c_h

O (la) DEAD WEIGHT z

O y (2a,2b) SEISMIC LOADS 2

8 (3b,3d) CONTAINMENT PRESSURE AND TEMPERATURE LOADS S

(7a-7d)

CHUGGING LOADS A ,

$ (8a) SRV DISCHARGE LOADS l l

(8a) SRV DISCHARGE LOADS y (SETPOINT ACTUATION) 1 (ADS arTtTATTOM) 8 i l m i  :

(9a) PIPING REACTIONS LOADS l

l l (10a) CONTAINMENT INTERACTION LOADS

l
0. 300. 600. 1200.

TIME AFTER LOCA (sec)

Figure 3-2.2-11 VENT SYSTEM SBA EVENT SEQUENCE I

i f) DET-04-028-3 0 Revision 0 3-2.102 l

l nutggh 1

O (la) DEAD WEIGHT 8

5 (2a,2b) SEISMIC LOADS R

0 C (3b,3d) CONTAINMENT PRESSURE AND TEMPERATURE LOADS k

8 H (6a,6c,6e) CONDENSATION n

OSCILIATIQ4 IDADS l(7a-7d)

CHUGGING LOADS m ,' i

a (8a) SRV DISCHAPGE LOADS i (8a) SRV DISCHARGE LOADS S (SETPOINT ACTUATION) '

(ADS ACTUATION)

U l t

$ I  !

(9a) PIPING REACTION LOADS i 8 i I e

(10a) CONTAINMENT INTERACTION LOADS I i I

O. 5. 300. 500.

TIME AFTER LOCA (sec)

Figure 3-2.2-12 V_ENT SYSTEM IBA EVENT SEQUENCE I DET-04-028-3 Revision 0 3-2,103 h1 l nutg,qh l l

/]

kJ (la) DEAD WEIGHT (2a,2b) SEISMIC LOADS z

O y (4a) VENT SYSTEM DISCHARGE LOADS z

O H

El o (3d) CONTAINMENT TEMPERATURE LOADS C

O (Sa-Se) POOL SVELL LOADS rA ,

$ l I d l l (6b,6d,6f) CO LOADS A l l '

I (7a-7d)

[ l  ; ,' CHUGGING LOADS U i W ' i ' *

(8a) SRV _ _

/ DISCHARGE LOADS SEE NOTE 1 (9a) PIPING REACTION LOADS l l l l (10a) CONTAINMENT INTERACTION LOADS l l l l 0.1 1.5 5.0 35.0 65.0 TIME AFTER LOCA (sec)

Note:

1. The SRV discharge loads which occur during this phase of the DBA event are negligible.

Figure 3-2.2-13 VENT SYSTEM DBA EVENT SEQUENCE f~' PET-04-028-3 k-Revision 0 3-2.104 nutggh

3-2. 3 Analysis Acceptance Criteria g The acceptance criteria defined in NUREG-0661 on which the Fermi 2 vent system analysis is based are discussed in Section 1-3. 2. In general, the acceptance criteria follows the rules contained in the ASME Code,Section III, Division 1 including the Summer 1977 Addenda for Class MC components and component supports (Reference 4). The corresponding service limit assign-ments, jurisdictional boundaries, allowable stresses, and fatigue requirements are consistent with those con-tained in the applicable subsections of the ASME Code and the Mark I Containment Program Plant Unique Analysis Application Guide (PUAAG) (Reference 5). The acceptance $

criteria used in the analysis of the vent system are summarized in the paragraphs whi.ch follow.

The items examined in the analysis of the vent system include the vent lines, vent header, downcomers, the support columns and associated support elements, the drywell shell near the vent line penetrations, the vent header deflectors, the downcomer-vent header intersec-tion stiffener plates and bracing system, the vacuum breaker support system, the vent line-SRV piping pene-tration assembly, and the vent line bellows assembly.

DET-04-028-3 Revision 0 3-2.105 nutggh

O whe evectric ce ge e e vece- e eecieeed its eecw et these items are identified in Figures 3-2.1-1 through 3-2.1-13.

The vent lines, vent header, downcomers, the support column ring plate away from the pin locations, the dry-well shell, the downcomer-vent header intersection stif-fener plates, the ring plates and stiffener plates attached to the vent line-vent header intersection, the vacuum breaker nozzle, and the vent line-SRV piping penetration assembly are evaluated in accordance with the requirements for Class MC components contained in Subsection NE of the ASME Code. Fillet welds and partial penetration welds joining these component parts or attaching other structures to these parts are also examined in accordance with the requirements for Class MC welds contained in Subsection NE of the ASME Code.

The support columns, the downcomer bracing members, the J

vacuum breaker support beam, and the associated connect-ing elements and welds are evaluated in accordance with the requirements for Class MC component supports con-tained in Subsection NF of the ASME Code. The vent I

header deflectors and associated component parts and wel'ds are also evaluated in accordance with the require-l O

l DET-04-028-3 Revision 0 3-2.106

ments for Class MC component supports with allowable g stresses corresponding to Service Level D.

As shown in Table 3-2.2-25, the NOC I, SBA II, IBA I, DBA I, and DBA II combinations all have Service Level B limits while the DBA III combination has Service Level C limits. Since these load combinations have somewhat different maximum temperatures, the allowable stresses for the two load combination groups with Service Level B and C limits are conservatively determined at the high-est temperature for each load combination group.

The allowable stresses for all the major components of the vent system, such as the vent line, vent header and g downcomers, are determined at the maximum DBA tempera-ture of 292'F. The allowable stresses for the remaining vent system component parts away from the vent line-SRV piping penetration nozzle are determined at 17 3'F . The allowable stresses for the vent line-SRV piping nozzle and adjoining component parts are determined at 36 3'F.

The allowable stresses for the load combinations with Service Level B and C limits are shown in Table 3-2.3-1.

The allowable displacements and associated number of cycles for the vent line bellows are shown in DET-04-028-3 Revision 0 3-2.107 nutp_qh

( ,) Table 3- 2 . 3- 2 . These values are taken from the FSAR, as permitted by NUREG-0661 in cases where the analysis technique used in the evaluation is the same as that contained in the plant's FSAR. The annular ring and the associated attachment weld to the vent line shown in Figure 3-2.1-8 are evaluated in accordance with the requirements for Class MC components as discussed above.

The acceptance criteria described in the preceding para-graphs result in conservative estimates of the existing margins of safety and ensure that the original vent system design margins are restored.

,3

? )

v UJ DET-04-028-3 Revision 0 3-2.108 nutggh

Table 3-2.3-1 ALLOWABLE STRESSES FOR VENT SYSTEM COMPONENTS AND COMPONENT SUPPORTS O

m ter M (l) S uess Allowable Stress (ksi)

Itars Material Properties Type w ee (2) wee (3s.

(ksi) Ievel B Irwel C C0MPONENTS S = 19.30 IIcal Primary 28.95 50.96 Drywell SA-516 c Shell Gr. 70 = 22*68 Pr

~mt Secongmary +(4)

Sy = 33.97 p ag9 Stress 68.04 N/A S 19.30 Primary Fisrbrane 19.30 33.97 SA-5 Ircal Primary S ,1 = 22.68 28.95 50.96 Mntbrane Primary +(4) y = 33.97 ,,econdary S

s Stress Rance 68.04 N/A S = 19.30 Primary Marbrane 19.30 33.97 Vent SA-516 S,1 = 22.68 Iccal Primary 28.95 50.96 Header Gr. 70 Mmbrane S = 33.97 3econgmary Pr + (4)

Y ary Stress 68.04 N/A R ancie 8 = 19.30 Primary Matbrane mc 19.30 33.97

^~ 1 = .8 Iocal Pr W Downcaner mi 28.95 50.96 Gr. 70 Manbrane S = 33.97 Primary + ( 4 )

SecongrgStrest 68.04 N/A

= 9.10 Primary Marbrane Support mc 19.30 33.97 C

  • SA-516 Incal Primary S = 22.69 28.95 50.96 Plate S = 33.97 Primary +(4) y Secong g Stress 68.04 W/A 8 = 16.50 mc Primary Fksrbrane 16.50 30,25 SRV Piping Penetratim SA-333 S,, = 20.00 Incal Prin'ry 24.75 45.37 Nozzle Gr. 6 Marbrane S = 30.25 Primary + (4)

Y 60.00 Secong 4 Stres N/A DET-04-028-3 Revision 0 3-2.109 nutp_qh

Table 3-2.3-1 (Continued)

ALLOWABLE STRESSES FOR VENT SYSTEM COMPONENTS AND COMPONENT SUPPORTS I' Allowable Stress (ksi)

Item Material Properties Service (2) Service (3)

Type (ksi) I Level B Level C COMPONENT SUPPORTS Bending 19.64 26.19 Tensile 19.64 26.19 Column SA-106 S = 32.74 Gr. B y Combined 1.00 1.00 Compressive 16.45 21.88 Interaction 1.00 1.00 WELDS m Primary 15.01 26.42 Rina Plate SA-516 to Vent Gr. 70 " '97 Header y Secondary 45.03 N/A SRV Piping 8

  • mc Primary 12.38 22.69 Penetration SA-333 S Slee o Gr. 6 W = 20.00 g

y = 30.25 Secondary 45.00 N/A Notes: I

1. Material properties taken at maximum event temperatures.
2. Service Level B allowables are used when evaluating NOC I, SBA II, IBA I, DBA I, and DBA II load combination results.
3. Service Level C allowables are used when evaluating the DBA III Load combination results.
4. Thermal bending stresses are excluded when evaluating primary-plus-secondary stress ranges.
5. Evaluation of primary-plus-secondary stress intensity range and fatigue are not required for load combination DBA I.

l 6. The allowable stresses for local primary membrane stresses at penetrations are increased by 1.3 when evaluating load combinations DBA I and DBA II.

7. Stresses due to thermal loads may be excluded when evaluating component supports.

DET-04-028-3

& b Revision 0 3-2.110 OULhy

O Table 3-2.3-2 ALLOWABLE DISPLACEMENTS AND CYCLES FOR VENT LINE BELLOWS Allowable Type Value Compression 0.875 in.

Axial -

Extension 0.375 in.

Meridional +0.625 in.

Lateral Imgitudinill +0.625 in.

Number of Cycles of Maximum Displacements 500 g DET-04-028-3 e

Revision 0 3-2.111 nutp_qh

3-2.4 Method of Analysis The governir.g loads for which the Fermi 2 vent system is  ;

I evaluated are presented in Section 3-2.2.1. The method-ology used to evaluate the vent system for the .overall  ;

i l effects of all loads, except those which exhibit asym- t i

metric characteristics, is discussed in Section 3-2.4.1. i

. The effects of asymmetric loads on the vent system are ,

t evaluated using the methodology discussed in Section i 3-2.4-2. The methodology used to examine the local effects at the penetrations and intersections of the  ;

vent system- major components is discussed in Section 3-2. 4. 3.  !

O I The methodology used to formulate results for the con- [

trolling load combinations, examine fatigue effects, and [

evaluate the analysis results for comparison with the ,

applicable acceptance limits, is discussed in ,

i Section 3-2. 4.4. [

t

, i I

i

\

t

\ DET-04-028-3 I Revision 0 ~3-2.112 nutsch

3-2.4.1 Analysis for Major Loads g The repetitive nature of the vent system geometry is such that the vent system can be divided into 16 iden-tical segments which extend from midbay of the vent line bay to midbay of the non-vent line bay, as shown in Figure 3-2.1-6. The governing loads which act on the vent system, except for seismic loads and a few chugging load cases, exhibit symmetric and/or anti-symmetric characteristics with respect to a 1/16th segment of the vent system. The analysis of the vent system for the majority of the governing loads is therefore performed for a typical 1/16th segment.

O A beam model of a 1/16th segment of the vent system, as shown in Figure 3-2.4-1, is used to obtain the response of the vent system to all loads except those which result in asymmetric effects on the vent system. The model includes the vent line, vent header, downcomers, and the support columns. The model also includes the vent header deflectors, the downcomer bracing system, and the vacuum breaker and vacuum breaker support sys-tem. The portion of the SRV piping and its associated supports on the vent system, which extends from the vent line-SRV piping penetration to the ramshead, is also DET-04-028-3 Revision 0 3-2.113 nutggh

included to account for the interaction ef fects of these two. structures.

The local stiffness effects at the penetrations and intersections of the major vent system components, shown in Figures 3-2 .1-7 through 3-2.1-12, are included using stiffness matrix elements of these penetrations and intersections. A matrix element for the vent line-dry-well penetration, which connects the upper end of the-I vent line to the spherical transition segment, is devel-oped_using the finite dif ference model of the penetra-tion shown in Figure 3- 2 . 4 - 9 . The finite element model of the vent line-SRV piping penetration shown in O F19"re 3-2. 4-10, is used to develop a matrix element which connects the beams on the centerline of the vent line to the SRV piping penetration nozzle. A matrix element which connects the lower end of the vent line to a

the beams on the centerline of the vent header is developed using the finite element model of the vent line-vent header intersection shown in Figure 3-2.4-11.

Finite element models of each downcomer-vent header 1 intersection, similar to the one shown in Figure 3-2.4-12, are used to develop matrix elements which connect the beams on the centerline of the vent header l

h

( V DET-04-028-3 Revision 0 3-2.114

to the upper ends of the downcomers at the downcomer ring locations. These elements also connect the attach-ment points of the vent header deflector to the down-comer crotch plates. The length of the vent header segment in the analytical models used for downcomer-vent header intersection stiffness determination is increased to ensure that vent header ovaling effects are properly accounted for. Use of this modeling approach has been verified using results from FSTF tests. Additional information on the analytical models used to evaluate the penetrations and intersections of major vent system components is contained in Section 3-2. 4. 3.

The local stiffness effects at the attachments of the downcomer bracing, vent header deflectors, vacuum breaker supports, vent system support columns, and SRV piping to support rings and pad plates located on the major components of the vent system are also included.

Beams which account for the local stiffness of the sup-port rings and pad plates are used to connect the asso-ciated component parts to beams which model the vent line, vent header, and downcomers.

The 1/16th beam model contains 231 nodes, 2 38 beam e'ements, and 6 matrix elements. The node spacing used DET-04-028-3 Rcvision 0 3-2.115 nutggh

O in the ene1retca1 mode 1 is refined to ensure edeeeate distribution of mass and determination of component part frequencies and mode shapes, and to facilitate accurate application of loadings. The stiffness and mass proper-ties used in the model are based on the nominal dimen-sions and densities of the materials used to construct the vent system. Small displacement linear-elastic behavior is assumed throughout.

The boundary conditions used in the 1/16th beam model are both physical and mathematical in nature. The phys-ical boundary conditions include the elastic restraints provided at the attachments of the support columns and the SRV piping ramshead support to the suppression cham-j ber ring beam and pedestal, The associated stiffnesses are developed using the analytical model of the suppres-sion chamber described in Volume 2 of this report. The vent system columns are assumed to be pinned in all directions at their upper and lower ends. Additional physical boundary conditions include the elastic restraints provided at the attachment of the vent line l

to the drywell. The associated vent line-drywell penetration stiffnesses are included as a stiffness matrix element, the development of which is discussed in the preceding paragraphs. The mathematical boundary O DET-04-028-3 Revision 0 3-2.116 nutggb

r conditions consist of either symmetry, anti-symmetry, or a combination of both at the midcylinder planes, depend-ing on the characteristics of the load being evaluated.

Additional mass is lumped along the length of the sub-merged portions of the downcomers, support columns, and SRV piping to account for the effective mass of water which acts with these components during dynamic load-ings. The total mass of water added is equal to the mass of water displaced by each of these components.

For all but the pool swell and condensation oscillation dynamic loadings, the mass of water inside the submerged portion of the downcomers is included. The downcomers are assumed to contain air and/or steam during pool 9 swell and condensation oscillation, the mass of which is neglected. The mass of water inside the submerged por-tion of the SRV piping is also included for all dynamic loadings. An additional mass of 1125 lbs to account for the weight of the drywell/wetwell vacuum breaker is lumped at the center of gravity of the vacuum breaker.

A frequency analysis is performed using the 1/16th beam model of the vent system for the case with water inside the downcomers and the case with no water inside the downcomers. All structural modes in the range of 0 to DET-04-028-3 Revision 0 3-2.117 nutp_qh

50 hertz and 0 to 200 hertz, respectively, are extracted for these cases. The resulting frequencies and mass participation factors are shown in Tables 3- 2 . 4 -1 and 3-2.4-2.

A dynamic analysis is performed for the pool swell loads and condensation oscillation loads specified in Section 3-2.2-1, using the 1/16th beam model of the vent system.

The analysis consists of a transient analysis for pool swell loads, and a harmonic analysis for condensation oscillation loads.

The modal superposition technique, including modes to 200 hertz with 2% damping, is utilized in both the transient and harmonic analyses.

e The pool swell and condensation oscillation load frequencies are enveloped by including vent system frequencies to 200 hertz.

The remaining vent system load cases specified in Sec-tion 3-2.2.1 involve either static loads or dynamic loads, which are evaluated using an equivalent static approach. For the latter, conservative dynamic amplifi-cation factors are developed and applied to the maximum spatial distributions of the individual dynamic

, loadings.

I l-l f"~5 d DET-04-028-3 Revision 0 3-2.118 1

nutggb

The effects of asymmetric loads are evaluated by apply-ing loads generated using the 180' beam model discussed in Section 3-2.4.2 to the 1/16th beam model. Displace-ments taken from the 180' beam model results are imposed at the midcylinder boundary planes of the 1/16th beam model. Inertia forces due to horizontal seismic loads and concentrated forces due to asymmetric chugging loads which are also taken from the 180* beam model results, are applied to the portion of the 1/16th beam model which lies between the midcylinder boundary planes.

Additional information related to the vent system analysis for asymmetric loads is provided in Section 3-2. 4. 2.

O The 1/16th beam model is also used to generate loads for the evaluation of stresses in the major vent system com-ponent penetrations and intersections. Beam end loads, distributed loads, reaction loads, and inertia loads are developed and applied to the analytical models of the vent system penetrations and intersections shown in Figures 3-2.4-9 through 3-2.4-12. Additional informa-tion related to the vent system penetrations and inter-section stress evaluation is provided in Section 3-2.4.3.

DET-04-028-3 O

Revision 0 3-2.119 nutggh

O The specific treatment of each load in the load catego-ries identified in Section 3-2,2.1 is discussed in the paragraphs which follow.

1. Dead Weight Loads t
a. Dead Weight of Steel: A static analysis is performed for a unit vertical acceleration applied to the weight of vont system steel.
2. Seismic Loads
a. OBE Loads: A static analysis is performed for a 0.0679 vertical seismic acceleration applied

(} to the weight of steel included in the 1/16th beam model. An additional static analysis is performed for the boundary displacements and associated inertia loads generated for a 0.23g seismic acceleration applied in each horizon-tal direction using the 180' beam model. The l

results of the three earthquake directions are combined using SRSS.

b. SSE Loads: The procedure used to evaluate the 0.133g vertical and 0.46g horizontal -SSE )

l seismic accelerations is the same as that dis- l l

cussed for OBE seismic loads in load case 2a. j O

J DET-0 4-0 28- 3 '

Revision 0 3-2.120 nutagh i

3. Containment Pressure and Temperature Loads O
a. Normal Operating Internal Pressure Loads: A static analysis is performed for a 2.0 psi internal pressure applied as concentrated forces to the unreacted areas of the vent system.
b. IOCA Internal Pressure Loads: A static anal-ysis is performed for the SBA and IBA net internal pressures applied as concentrated forces to the unreacted areas of the major components of the vent system. These pres-sures are shown in Figures 3-2.2-1 through g 3-2.2-3. The effects of DBA internal pressure loads are included in the pressurization and thrust loads discussed in load case 4a.

Concentrated forces are also applied at the vent line-drywell penetration location using the SBA, IBA, and DBA drywell internal pres-sures. These forces account for the pressures acting on the vent line-drywell penetration unreacted area and for the movement of the drywell due to internal pressure. The move-DET-04-028-3 Revision 0 3-2.121 h

nutggh

)

1 ment of the suppression chamber due to inter-nal pressure, although small in magnitude, is t

also applied.

c. Normal Operating Temperature Loads: A static analysis is performed for the case with the containment at an ambient temperature of 70*F and a 363*F temperature uniformly applied to the wetwell SRV piping. The reaction loads at the vent line-SRV piping penetration are also applied. The methodology used to evaluate  :

local thermal effects in the vent line-SRV piping penetration is discussed in Section

] 3-2. 4. 3.

An additional static analysis is performed for the maximum normal operating temperature listed in Table 3-2. 2-2. This temperature is uniformly applied to the portion of the vent 3 system inside the suppression chamber. Cor-responding temperatures of 70*F for the dry-well and vent system components outside the suppression chamber, 173'F for the suppression chamber, and 36 3

  • F for the SRV piping are also applied in this analysis.

O o8T-o4-o28-3 Revision 0 3-2.122 nutggb

O

d. LOCA Temperature Loads: A static analysis is performed for the SBA, IBA, and DBA tempera-tures, which are uniformly applied to the major components and external components of the vent system. These temperatures are shown in Figures 3-2.2-4 through 3-2.2-6. A temperature of 36 3
  • F is also uniformly applied to the SRV piping for those controlling load combinations which include SRV discharge loads.

Concentrated forces are applied at the vent line-drywell penetration and at the support g column and SRV piping attachment points to the suppression chamber to account for the thermal expansion of the drywell and suppression cham-ber during the SBA, IBA, and DBA events. The greater of the temperatures specified in Figure 3-2.2-4 and Table 3-2.2-2 is used in the analysis for SBA temperatures.

4. Vent System Discharge Loads
a. DBA Pressurization and Thrust Loads: A static analysis is performed for the DBA pressuriza-tion and thrust loads shown in Table 3-2. 2-3.

DET-04-028-3 9

Revision 0 3-2.123 nutggh

l O

5. Pool Swell Loads ,
a. Vent System Impact and Drag Loads:

A dynamic analysis is performed for the vent line, downcomer, and vent header deflector pool swell impact loads shown in Table 3-2.2-4 and in Figures 3-2. 2-7 and 3-2. 2-8.

b. Impact and Drag Loads on Other Structures: A dynamic analysis is performed for pool swell impact loads on the downcomer bracing members and ring plates, and on the vacuum breaker and vacuum breaker supports. These loads are shown in Table 3-2. 2-5. The pool swell impact loads acting on the SRV piping and support located beneath the vent line are also applied.
c. Froth Impingement and Fallback Loads: A dyna-mic analysis is performed for froth impinge-l ment and fallback loads on the downcomer l l

bracing members and ring plates, and on the vacuum breaker and vacuum breaker supports.

These loads are shown in Table 3-2. 2-6. The froth impingement loads acting on the SRV O' DET-04-028-3 Revision 0 3-2.124 nutggh

piping and the support located beneath the h vent line are also applied,

d. Pool Fallback Loads: A dynamic analysis is performed for pool fallback loadc on the down-comer bracing members and ring plates. These loads are shown in Table 3-2. 2-7. The pool fallback loads acting on the SRV pl i ig cond the support located beneath the vent line are also applied.
e. LOCA Air Clearing Submerged Structure Loads:

An equivalent static analysis is performed for LOCA air clearing submerged structure loads on the downcomers and support columns. These loads are shown in Tables 3-2. 2-8 and 3-2. 2-9.

The values of the loads include dynamic amplification factors which are computed using first principles and the dominant frequencies of the downcomer and the support columns. The dominant frequencies are derived from harmonic analyses of these components. The results of these harmonic analyses are shown in Figures 3-2.4-2 and 3- 2 . 4 - 3. The LOCA air clearing submerged structure loads acting on the DET-04-028-3 Revision 0 3-2.125 nutp_qh

submerged portion of the SRV piping are also applied.

6. Condensation Oscillation Loads
a. IBA Condensation Oscillation Downcomer Loads:

i A dynamic analysis is performed for the IBA i condensation oscillation downcomer loads shown in Table 3-2. 2-10 and Figure 3-2.2-9. The dominant downcomer frequency is determined from the harmonic results shown in Figure  !

3-2.4-4. It is apparent from this figure that i

the dominant downcomer frequency occurs in the frequency range of the second condensation oscillation downcomer load harmonic. The first and third condensation oscillation down-comer load harmonics are therefore applied at frequencies equal to 0.5 and 1.5 times the value of the dominant downcomer frequency.

b. DBA Condensation Oscillation Loads: The pro-cedure used to evaluate the DBA condensation ,

oscillation downcomer loads shown in Table 3-2.2-11 is the same as that discussed for IBA l

condensation oscillation downcomer loads in load case 6a.

DET-04-028-3 Revision 0 3-2.126 nutagh l

1-g \

= - )

c. IDA Condensation Oscillation Vent System Pressures: A dynamic analysis is performed for IBA condensation oscillation vent system pressures on the vent line and vent header.

These loads are shown in Table 3-2.2-12. The dominant vent line and vent header frequencies are determined from the harmonic analysis

  • s results shown in Figure 3-2.4-5. An addi- s tional static analysis is performed for a 1.5 psi internal pressure applied as concen-trated forces to the unreacted areas of the vent system.
d. DBA Condensation Oscillation Vent System Pressure Loads: The procedure used to evalu-ate the DBA condensation oscillation vent system pressure loads shown in Table 3-2.2-12 is the same as that discussed for IBA conden-sation oscillation vent system pressure loads in load case 6c.
e. IBA Condensation Oscillation Submerged Struc-ture Loads: As previously discussed, pre-chug loads described in load case 7c are specified in lieu of IBA condensaton oscillation loads.

l DET-04-028-3 '

Revision 0 3-2.127 nutggh 1

-~

i  ; T ,

- ,5 i

( ,

> 1  % i

. ' '\ +

s

, 3

'O

. h.  %

, ,'r s 5 gc T h k g .,

3

y. ,

e -

f. DBA Condensation'Oscillat, ion Submerged Struc-S -

ture Lcacsp Ah.pquivalent static analysis is

't \

, s performed Ifor tht! DBA condensation oscillation

- i submerg.ed structure loads on the support 3

^

colu't. ins. These' loads are shown in Table k < ': t,,

s3-2.2-13. Tne loads include dynamic a:aplifi-3 s .

l V

cation factors which are computed using the

,me thodo' logy d'escribed for LOCA air clearing i

, submerged . structure loads in load case 5e.

'2hc DBA' condensation oscillation submerged structure loads acting on the submerged portion of the SRV piping are also' applied.

O ,

7. Chugging Loads
a. Chugging Downcomer Lateral Loads: A harmonic analysis of the downcomers is performed to determine the dominant downcomer frequency for use in calculating the maximum chugging load magnitude. The harmonic analysis results are shown in Figure 3-2.4-6. The resulting chugg-

,' ing load magnitudes are shown in Table 3-2.2-14. A static analysis using the 1/16th beam model is performed for chugging downcomer lateral load cases. 8 through 22. These load DET-04-028-3 Revision 0 3-2.128 0 nutggh

cases are shown in Tables 3-2.2-16 and h 3-2.2-17. An additional static analysis using the 180* beam model is performed for boundary displacements and associated concentrated forces generated for load cases 1 through 7.

A static analysis is also performed for the maximum chugging load shown in Table 3-2.2-18, applied to a single downcomer in the in plane and out-of plane directions. The results of this analysis are used in evaluating fatigue.

b. Chugging Vent System Pressures: An equivalent static analysis is performed for the chugging vent system pressures applied to the unreacted areas of the vent system. These loads are shown in Table 3-2.2-19. The dominant vent line and vent header frequencies are deter-mined from the harmonic analysis results shown in Figure 3-2.4-7.
c. Pre-Chug Submerged Structure Loads: An equi-valent static analysis is performed for the pre-chug submerged structure loads on the support columns. These loads are shown in DET-04-028-3 Revision 0 3-2.129 nutggh

Table 3-2. 2-20. The loads include dynamic amplification factors which are computed using the methodology described for submerged structure LOCA air clearing loads in load case Se. The pre-chug submerged structure loads acting on the submerged portion of the SRV piping are also applied.

Submerged The

d. Post-Chug Structure Loads:

procedure used to evaluate the post-chug sub- '

merged structure loads on the support columns is the same as that discussed for pre-chug submerged structure loads in load case 6c.

These loads are shown in Table 3-2.2-21.

8. Safety Relief Valve Discharge Loads
a. SRV Discharge Air Clearing Submerged Structure Loads: An equivalent static analysis is per-formed fcr SRV discharge drag loads on the downcomers and support columns. These loads are shown in Tables 3-2.2-22 and 3-2.2-23. i i

The loads include a dynamic load factor of 3.0 as discussed in Section 1-4.2.4. A dynamic

, load factor of 2.0 is used for the downcomer  ;

t loads applied in the out-of plane direction, DET-04-028-3 ,

Revision 0 3-2.130 nutggh .

since the out-of plane downcomer frequency is g well above the maximum SRV discharge load

~

frequency, as shown in Figure 3-2.4-2. The SRV discharge submerged structure loads acting on the submerged portion of the SRV piping are also applied.

9 Piping Reaction Loads

a. SRV Piping Reaction Loads: As previously discussed, the wetwell SRV piping is included in the 1/16th beam model of the vent system.

Loads in categories 1 through 8 which act on the vent system and the wetwell SRV piping are applie.

8

/ \ l i ! Lf l A o

B 0.0 i WAX i

/v %#a ,

(~]

v 1.0 10.0 20.0 30.0 40.0 50.0 Frequency (Hz)

Notes:

1. Results shown are obtained by applying unit drag pressures to submerged portion of dow" comers in the in-plane and out-of-plane directions.
2. Frequencies are determined with water inside submerged portion of downcomers.
3. Results shown are typical representative of all downcomers.

Figure 3-2.4-2 HARMONIC ANALYSIS RESULTS FOR DOWNCOMER SUBMERGED STRUCTURE l LOAD FREQUENCY DETERMINATION i

C)

G DET-04-028-3 Revision 0 3-2.138 1 nutggh

O In-plane, f cr = 24.74 Hz Out-of-plane, f cr = 17.17 Hz 2 . 0 --

a C

o E

o O

to H

a.

m -Cut-of-plane O Y i

$ 1.0 l 4 il '

y - In-plane f{

$ o' a h h,) k ik

0. 0 - i i i i 0.0 20.0 40.0 60.0 80.0 100.0 Frequency (Hz)

Notes:

1. Results shown are obtained by applying unit drag pressures to submerged portion of columns in the in-plane and out-of-plane directions relative to the mitered joint.
2. Results shown are typical for inside and outside columns.

Figure 3-2.4-3 HARMONIC ANALYSIS RESULTS FOR SUPPORT COLUMN SUBMERGED STRUCTURE LOAD FREQUENCY DETERMINATION Revision 0 3-2.139 ,

nutKh - ,

Downcomer, f = 14.2 Hz cr a

$ .010 o

0 a

a C

$ .005 "

a u

O E J L l

C 5

0.00 1

% suA/ b

%Ju i

fAJ u i 1.0 10.0 20.0 30.0 40.0 50.0 0- Frequency (Hz)

Notes:

1. Results shown are obtained by applying unit internal pressures to one downcomer in a downcomer pair.
2. Frequencies are determined without water inside submerged portion of the downcomers.
3. Results shown are typical for all downcomers.

Figure 3-2.4-4 HARMONIC ANALYSIS RESULTS FOR CONDENSATION OSCILLATION DOWNCOMER LOAD FREQUENCY DETERMINATION O

DET-04-028-3 Revision 0 3-2.140 nutggh

1 l

l I

O Vent Line, f = .0 Hz cr Vent Header, f = 28.5 Hz

.10

  • ' 1

$ F DC/VH Int.

g 0

yVertical Disp. '

1:

N V. j

- N i a '

Vent Line n 's

.$ Axial Disp) foil l C  !! !  !

E i l /

B m  !

! \

l

\ I

> I' u) , i <. ,

a

_! l \ . t f J /!bA i V

'l \ n'j \

V N A

%# ff \/

l /' (

y -

N' \/ u

.00 i 1.0 10.0 20.0 30.0 40.0 50.0 Frequency (Hz)

Note:

1. Results shown are obtained by applying 2.5 psi internal pressures to unreacted areas of vent system.

Figure 3-2.4-5 HARMONIC ANALYSIS RESULTS FOR CONDENSATION OSCILLATION VENT SYSTEM PRESSURE LOAD FREQUENCY DETERMINATION O

DET-04-028-3 Revision 0 3-2,141 nutp_qh

l I

O Downcomer, f = 12.4 Hz cr 4.

e a

o E

O a

O -

en r4 O

Q 2.-

u e

A W

e E

o ) L 8

g - ) \w -- - A O 0. I i i I i 1.0 10.0 20.0 30.0 40.0 50.0 o

Frequency (Hz)

Notes:

1. Results shown are obtained by applying unit forces to downcomer ends in the plane of the downcomers in the same direction.
2. Frequencies are determined with water inside submerged portion of the downcomer.
3. Results shown are typical for all downcomers.

Figure 3-2.4-6 HARMONIC ANALYSIS RESULTS FOR CHUGGING DOWNCOMER LATERAL

( LOAD FREQUENCY DETERMINATION DET-04-028-3 Revision 0 3-2,142 g{

O Vent Line, f = 18.5 Hz cr Vent Header, f = 39.0 Hz

.10 i

m 6 9 ft

$ DC/VHDisp.

Vertical Int. D'q E l b l Il d l!

a 1 f .05 - -

f !,

E Vent Line

$ Axial Disp. D A f} )

I . . ) O!\ / , //1 I in f

} Ji

[,i k[

'^

ll Lh f

(M k M ll V\

'l \

V e

.00 I i a i 1.0 10.0 20.0 30.0 40.0 50.0 Frequency (Hz)

Note:

1. Results shown are obtained by applying 2.5 and 3.0 psi internal pressures to unreacted areas of vent line and vent header, respectively.

Figure 3-2.4-7 HARMONIC ANALYSIS RESULTS FOR CHUGGING VENT SYSTEM PRESSURE LOAD FREQUENCY DETERMINATION D"_-04-028-3 3-2.143 Revision 0 g

1 l

l l

3-2.4.2 Analysis for Asymmetric Loads G

O The asymmetric loads which act on the vent system are evaluated by decomposing each of the asymmetric loadings into symmetric and/or asymmetric components with respect to a 180* segment of the vent system. The analysis of the vent system for asymmetric loads is performed for a typical 180* segment of the vent system cut along the plane of a principal azimuth. .

A beam model of a 180* segment of the vent system, shown ir} Figure 3-2.4-8, is used to obtain the response of the vent system to asymmetric loads. The model includes the vent line, vent header, downcomers, and support columns.

Many of the modeling techniques used in the 180* beam model, such as those used for local mass and stiffness determination, are the same as those utilized in the ,

1/16th beam model of the vent system discussed in Section 3-2.4.1. The local stiffness effects at the vent line-drywell penetrations and vent line-vent header intersections are included using stiffness matrix ele-ments for these penetrations and intersections. The local stiffness effects at the attachments of the support columns to the support ring on the vent header f^ DET-04-028-3

(,g/ Revision 0 3-2.144 t l

l nutg,qb :

l

are included using beams which account for the local g stiffness of the support ring.

The 180* beam model contains 251 nodes, 258 beams, and 16 matrix elements. The model is less refined than the 1/16th beam model of the vent system, and is used to characterize the overall response of the vent system to asymmetric loadings. It includes those component parts and local stiffnesses which have an effect on the overall response of the vent system. The stiffness and mass properties used in the model are based on the nominal dimensions and densities of the materials used to construct the vent system. Small displacement linear-elastic behavior is assumed throughout. h The bour.dary conditions used in the 180* beam model are both physical and mathematical in nature. The physical boundary conditions used in the model are similar to those used in the 1/16th beam model of the vent system.

The mathematical boundary conditions used in the model consist of either symmetry, anti-symmetry, or a combi-nation of both at the 0* and 180* planes. The specific boundary condition used depends on the characteristics of the load being evaluated.

DET-04-028-3 Revision 0 3-2.145 nutggh

O Additional mass is lumped along the length of the sub-G merged portion of the downcomers and support columns in a manner similar to that used in the 1/16th beam model. The mass of water inside the submerged portion of the downcomers is also included. An additional mass of 1125 lbs is lumped at the center of gravity of the drywell/wetwell vacuum breaker to account for its weight. The masses of other vent system component parts are also lumped at the appropriate locations in the model.

The asymmetric loads which act on the vent system in-clude horizontal seismic loads and asymmetric chegging loads as specified in Section 3-2. 2.1. An equivalent static analysis is performed for each of the loads using the 180' beam model.

The 180* beam model analysis results are used to gener-ate loads for use in the 1/16th beam model analysis.

This allows evaluation of the effects of asymmetric loads on the component parts of the vent system not included in the 180' beam model. Beam stresses in the vent line and vent header are examined for each asym-metric loading to determine which 1/16th segment or segments of the 180' beam model produce the maximum fx d DET-04-028-3 Revision 0 3-2.146 nutagh

response. The displacements at the midcylinder planes g of the controlling 1/16th segments are imposed on the corresponding midcylinder boundary planes of the 1/16th beam model. The inertia forces and concentrated forces acting on the 180' beam model between the midcylinder boundary planes are also applied to the 1/16th beam model at the appropriate node locations.

The magnitudes and characteristics of governing asym-metric loads on the vent system are presented and dis-cussed in Section 3-2. 2.1. The overall effects of asym-metric loads on the vent system are evaluated using the 180' beam model and the general analysis techniques discussed in the preceding paragraphs. The specific h treatment of each load which results in asymmetric loads on the vent system is discussed in the paragraphs which follow.

2. Seismic Loads
a. OBE Loads: A static analysis is performed for a 0.23g horizontal seismic acceleration applied to the weight of steel and water included in the 180* beam model. Seismic loads are applied in the direction of both principal azimuths.

DET-04-028-3 Revision 0 3-2.147 nutg_gh

l O b. SSE Loads: The procedure used to evaluate 0.469 horizontal SSE accelerations is the same as that discussed for OBE loads in load case 2a.  !

i

7. Chugging Loads t
a. Chugging Downcomer Lateral Loads: A static ,

analysis is performed for chugging downcomer i lateral load cases 1 through 7, shown in [

i-Table 3-2.2-16. [

l Use of the methodology described in the preceding 5 O

vereereew rese1te im e comeervetive eve 1eetio# or veme system response to the asymmetric loads defined in NUREG-0661, i

i r

t i  !

i r

i i

i t

i i

DET-04-028-3 Revision 0 3-2.148  !

1 nutggb !

r w.-,w - w-- - -- --

1 O

l

-s s (K]DW Y-4 'N

  • N i-

\ [K]vL/vH \

COMER (K]DW j X Y N- r[K]DW

(*1 DW

  • I VENT g LINE (TYP)[ \

/ / -

P ("i m va g

7 ,,,vr./vn ,

K '

SC /

['

(TYP)

SUPPORT E ER C.G.

$$[ j f I"'

Figure 3-2.4-8 VENT SYSTEM 180 BEAM MODEL-ISOMETRIC VIEW i

DET-04-028-3 Revision 0 3-2.149 nutggb

h 3-2. 4. 3 Analysis for Local Effects The penetrations and intersections of the major compo-I nents of the vent system are evaluated using refined analytical models of each penetration and intersection.

These include the vent line-drywell penetration, the vent line-SRV piping penetration, the vent line-vent header intersection, and the downcomer-vent h'eader in-tersections. The analytical models used to evaluate ,

these penetrations and intersections are shown in Figures 3-2. 4-9 through 3-2.4-12. An additional analy-tical model of the vent line-SRV piping penetration, shown in Figure 3-2.4-13 is used to evaluate local L

, O- thermal effects in the penetration.

Each of the penetration and intersection analytical models includes mesh refinement near discontinuities to facilitate evaluation of local stresses. The stiffness  ;

properties used in the model are based on the nominal dimensions of the materials used to construct the pene-trations and intersections. Small displacement linear-elastic theory is assumed throughout. ,

P The analytical models are used to generate local stiff-nesses of the penetrations and intersections for use in l l DET-04-028-3 Revision 0 3-2.150

  • l nutggh l

l I

the 1/16th beam model and the 180* beam model as dis- h cussed in Sections 3-2.4.1 and 3-2.4.2. Local stiff-nesses are developed which represent the stiffness of the entire penetration or intersection in terms of a few local degrees of freedom on the penetration or intersec-tion. This is accomplished either by applying unit forces or displacements to the selected local degrees of freedom, or by performing a matrix condensation to reduce the total stiffness of the penetration or inter-section to those of the selected local degrees of freedom. The results are used to formulate stiffness matrix elements which are added to the 1/16th Jeam model and the 180* beam model at the corresponding penetration or intersection locations.

In general, the shell segment lengths of the penetration and intersection analytical models used for stiffness calculations are extended to account for the ovaling stiffness of the respective shell segment. For example, the segments of the vent line, vent header, and down-comers at each of the penetrations and intersections are extended at least to the location of the first circum-ferential stiffener ring which inhibits shell ovaling.

DET-04-028-3 Revision 0 3-2.151 nutg_qh

The analytical models are also used to evaluate stresses in the penetrations and intersections. Stresses are computed by idealizing the penetrations and intersec-tions as free bodies in equilibrium under a set of sta-tically applied loads. The applied loads, which are extracted from the 1/16th beam model results, consist of loads acting on the penetration and intersection model boundaries and of loads acting on the interior of pene-tration and intersection models. The loads acting on the penetration and intersection model boundaries are  ;

the beam end loads taken from the 1/16th beam model analysis at nodes coincident with the penetration or intersection model boundary locations.

The loads which act on the interior of the penetration or intersection models consist of reaction loads and distributed loads taken from the 1/16th beam model results. The reaction loads include the forces and

, moments applied to the appropriate penetration or inter-section at the attachment points of the SRV piping, downcomer bracing, and vent header deflectors. The distributed loads include the pressures and acceleration loads applied to penetration and intersection models to account for internal pressure loads, thrust loads, pool swell loads, and inertia loads. By the application of DET-04-028-3 Revision 0 3-2.152 nutggb

boundary loads, reaction loads, and distributed loads to the penetration and intersection models, equilibrium of the penetrations and intersections is achieved for each of the governing vent system loadings.

Loads which act on the shell segment boundaries are applied to the penetration and intersection models through a system of radial beams. The radial beams extend from the middle surface of each of the shell segments to a node located on the centerline of the corresponding shell segment. The beams have large bend-ing stiffnesses, zero axial stiffness and are pinned in all directions at the shell segment middle surface.

g Boundary loads applied to the centerline nodes cause only axial and shear loads to be transferred to the shell segment middle surface with no local bending effects. Use of this boundary condition minimizes end effects on penetration and intersection stresses in the local areas of interest. The system of radial beams constrains the boundary planes to remain plane during loading, which is consistent with the assumption made in small deflection beam theory.

The methodology used to evaluate the overall ef fects of the governing loads acting on the vent system using the O

DET-04-028-3 Revision 0 3-2.153 nutg,gh

1/16th beam model is discussed in Section 3-2.4.1. The general methodology used to evaluate local vent system penetration and intersection stresses is discussed in the preceding paragraphs. A description of each vent system penetration and intersection analytical model and its use is provided in the paragraphs which follow.

o Vent Line-Drywell Penetration Axisymmetric Finite Dif ference Model: The vent line-drywell penetra-tion model shown in Figure 3-2.4-9 includes a seg-ment of the drywell shell, the jet deflector, the cylindrical penetration nozzle, the annular pad plate, and the spherical transition piece. The Q analytical model contains 9 segments with 175 mesh points. The reaction loads applied to the model include those computed at the upper end of the vent line. The distributed loads applied to the model include internal pressure loads.

o Vent Line-SRV Piping Penetration Finite Element Model: The vent line-SRV piping penetration model shown in Figure 3-2.4-10 includes a segment of the vent line, the penetration insert plate, the pene-tration nozzles, the penetration sleeves, the ring plates on the vent lines, and the associated pene-l DET-04-028-3 Revision 0 3-2.154 nutggb 1

- - , - . - . -- - A

tration stiffener plates. The model contains 1539 O

nodes, 186 beam elements, and 2222 plate bending and stretching elements. Boundary loads are applied at each end of the vent line shell segment.

The reaction loads applied to the analytical model include the drywell and wetwell SPV piping reaction loads. The distributed loads applied to the analytical model include internal pressure loads and inertia forces from dynamic loadings.

o Vent Line-Vent Header Intersection Finite Element Model- The vent line-vent header intersection finite element model shown in Figure 3-2.4-11 in- g cludes a segment of the vent line, a segment of the vent header with conical transitions, the vacuum breaker nozzles, the intersection ring plates and stitfener plates, the SRV piping supports located under the vent line, and the vacuum breaker support system. The model contains 1486 nodes, 160 beam elements, and 2296 plate bending and stretching elements. Boundary loads are applied at the end of the vent line shell segment, at each end of the vent header shell segment, and at the end of each vacuun breaker nozzle. The reaction loads applied to the analytical model include vent header O

DET-04-028-3 Revision 0 3-2.155 nutp_gh

i-I deflector reaction loads and SRV piping reaction-loads. The distributed loads applied to the analy-tical model include internal pressure loads ' and thrust loads, pool swell loads on the vent line and L vacuum breaker supports, and inertia forces from dynamic loadings.

o Downcomer-Vent Header Intersection Finite Element Model: The downcomer vent header intersection finite element model shown in Figure 3-2. 4-12 includes a segment of the vent header, a segment of each downcomer, the crotch plate, the downcomer rings, and the outer stiffener plates. The analy-O tic 1 oae1 co e ta= 924 nodes, 92 beam elements, and 1192 plate bending and stretching elements.

Boundary loads are applied at the ends of the vent header segment and at the ends of the downcomer segment. The reaction loads applied to the analytical model include the vent header deflector reaction loads and the downcomer bracing system reaction loads. The distributed loads applied to the model include internal pressure loads and thrust loads, pool swell loads on the downcomers and downcomer ring plates, and inertia forces from dynamic loadings.

DET-04-028-3 Revision 0 3-2.156

O

e. Vent Line-SRV Penetration Axisymmetric Finite Ele-ment Model: The vent line penetration model shown j in Figure 3-2.4-13 includes a piece of the vent line, the penetration insert plate, a segment of the SRV penetration nozzle, the penetration sleeves, and the upper and lower nozzle-to-sleeve l l

welds. The analytical model contains 306 nodes and 250 axisymmetric shell elements.

]

The analytical model is used to perform a transient thermal analysis of the penetration for a sustained SRV actuation. The penetration is initially assumed to be at 70*F, and is then subjected to an O

instantaneous temperature increase of 293'F at the inside surface of the penetration nozzle. Conser-vative values of heaa t transfer coefficients are used and transient temperatures in each of the analytical model components are calculated.

Stresses in the penetration nozzle, penetration sleeve, upper and lower nozzle-to-sleeve welds, and in the insert plate in the vicinity of the nozzle are calculated at several times during the transient. The maximum stresses for the times with the highest thermal gradients are combined with DET-04-028-3 9

Revision 0 3-2.157 nutp_gh

l l

O ta, e ero- the eme1reice1 ode 1 of the geeeereeton shown in Figure 3-2.4-10 for use in evaluating fatigue effects in the vent line-SRV piping penetration.

Use of the methodology described in the preceding para-graphs results in a conservative evaluation of vent system local stresses due to the loads defined in NUREG-0661.

O 1

O DET-04-028-3 Revision 0 3-2.158 nutagh

O i

i

[ Vent Line -Drywell Penetration of f

'Og 0,

  • 9

" S U Jet 9 Deflector e

I Drywell R Shell y  ; d w

"' Insert Plate I Nozzle 44.0" Figure 3-2.4-9 VENT LINE DRYWELL PENETRATION AXISYMMETRIC FINITE DIFFERENCE MODEL - VIEW OF TYPICAL MERIDIAN g DET-04-028-3 Revision 0 3-2.159 h

nutgg.h

I

/

S s

\

q D ) '

N f i

- - jY q

,5 fl x

%[:

o  :

s .

'il  ;

L

%a -

o ae _

b )3 :

--r

.s

( ;

I l ,

d :.I g , k3' L_ ib s

~F' $, '

r 5

?1' .'

b Figure 3-2.4-10 SRV PIPING-VENT LINE PENETRATION FINITE ELEMENT MODEL-ISOMETRIC VIEW O

DET-0 4 --0 2 8 -3 3-2.160 Revision 0 gg

l 9 l

/

>N; ph. 47 N'y ~

P il l-

\/ N-[.

s r 1 x t m i

/ \/ lN I .- .!'x tv'W r ' s ' te c._4q 7gggo w$

/M! HRW4 S?$

k Vk ^ kN)($ ,/

M .

W .

[

.n W'

N. .

$4 I/ g g2

~

I \/

?: i ) N&hMh '

X i'

 ?

g-agrM k L A mg$1CW N/

ibd WA l/Mwb / >c4 J%hl MD TN 1 Q?MMNWM>@$MlNl 4

@" g I

e .

m\w

_ mo vr 2 assi <i e_ d _.

d rTdhrbiD\WCSMEDLf45W~

4 , ,

V Figure 3-2.4-11 VENT LINE-VENT HEADER INTERSECTION FINITE ELEMENT MODEL-ISOMETRIC VIEW 9

DET-04-028-3 Revision 0 3-2.161 N{g

O

~ ~ ~ 4- x A /lX X X /W\\ IN bI [8\AA \'N1h W%M/NA b Ib x&gp / v'1 \/ \ M WK MA4 g/

/

x8MM N /M Th x D<MA@h%MAVD ~

V Y/X/KWAV\NA S VA/WL W '

p' '

c V/e , ~. > ky\s M l% % .k V% M pKV K M:) 0,%WNE_%MffX ~

4J F" jdLJ pt 7a I

c NN (Wl Figure 3-2. 4-12 DOWNCOMER-VENT HEADER INTERSECTION l p FINITE ELEMENT MODEL-ISOMETRIC VIEW u

i

"'I;;; 28-3 2-2 182 nut @ i

f e 1

6.375"R /

r SRV Pipe l

I

.L.

l i

j Weld L

I E3 g:_:..  : Sle. eve

~

II t

Airspace ET'

[I: - Insert Plate c Weld Vent Line I i 5

t..

I t

i i

L Figure 3-2.4-13 SRV PIPING-VENT LINE PENETRATION AXISYMMETRIC FINITE ELEMENT MODEL FOR LOCAL THERMAL ANALYSIS-VIEW OF TYPICAL MERIDIAN O

DET-04-028-3 R. vision 0 3-2.163 QQIg

O V) i 3-2.4.4 Methods for Evaluating Analysis Results '

The methodology discussed in Sections 3-2.4.1 and 3-2.4.2 is used to determine element forces and compo-

}

nent stresses in the vent system component parts. The [

methodology used to evaluate the analysis results, de- '

termine the controlling stresses in the vent system com-ponents parts and examine fatigue effects is discussed i

in the paragraphs which follow. ,

To evaluate analysis results for the vent system Class .

MC components, membrane and extreme fiber stress O intensities are computed. The values of the membrane stress intensities away from discontinuities are com- l t

puted using 1/16th beam model results. These stresses f

are compared with the primary membrane stress allowables contained in Table 3-2. 3-1. The values of membrane i stress intensities near discontinuities are computed ,

i using results from the penetration and intersection r

analytical models. These stresses are compared with local primary membrane stress allowables contained in Table 3-2.3-1. Primary stresses in vent system Class MC l component welds are computed using maximum principal >

l stresses or the resultant forces acting on the weld l

DET-04-028-3 l Revision 0 3-2.164 )

l nutggb

throat. The results are compared to primary weld stress h allowables contained in Table 3-2. 3-1.

Many of th e loads contained in each of the controlling load combinations are dynamic loads which result in stresses which cycle with time and are partially or fully reversible. The maximum stress intensity ranges for all vent system Class MC components are calculated using the maximum values of the extreme fiber stress differences which occur near discontinuities in the penetration and intersection analytical models. These stresses are compared to the secondary stress range allowables contained in Table 3-2.3-1. A simi ar procedure is used to compute the stress range for the vent system Class MC component welds. The results are compared to the secondary weld stress allowables contained in Table 3-2. 3-1.

To evaluate the vent system Class MC component supports, beam end loads obtained from the 1/16th beam model results are used to compute stresses. The results are compared with the corresponding allowable stresses contained in Table 3-2. 3-1. Stresses in vent system Class MC component support welds are obtained using the 1/16th beam model results to compute the maximum DET-04-028-3 Revision 0 3-2.165 nutp_qh

resultant force acting on the associated weld throat.

The results are compared to weld stress limits discussed in Section 3-2. 3. .

The controlling vent system load combinations are defined in Section 3-2.2.2. During load combination formulation, the maximum stress components in a particular vent system part at a given location are combined for the individual loads contained in each combination. The stress components for dynamic loadings are combined so as to obtain the maximum stress intensity.

O The maximum dif ferential displacements of the vent line bellows are determined using results from the 1/16 beam model of the vent system and the analytical model of the suppression chamber discussed in Volume 2 of this report. The displacements of the attachment points of the bellows to the suppression chamber and to the vent line are determined for each load case. The differ-

~

en ial displacement is computed from these values. The results for each load are combined to determine the total differential displacements for the controlling load combinations. These results are compared to the allowable bellows displacements in Table 3-2.3-2.

DET-04-028-3 Revision 0 3-2.166 nutg.gh

+

To evaluate fatigue effects in the vent system Class MC components and associated welds, extreme fiber alternat-ing stress intensity histograms for each load in each event or combination of events are determined. Fatigue effects for chugging downcomer lateral loads are eval-uated using the stress reversal histrograms shown in Table 3-2.2-18. Stress intensity histograms are devel-oped for the vent system major components and welds with the highest stress intensity ranges. Fatigue strength reduction factors of 2.0 for major component stresses and 4.0 for component weld stresses are conservatively used to account for peak stresses at all locations except at the SRV piping-vent line penetration where the -

welds are modeled explicitly to obtain peak stresses.

For each combination of events, a load combination stress intensity histogram is formulated and the corresponding fatigue usage factors are determined using the curve shown in Figure 3-2.4-14 The usage factors for each event are then summed to obtain the total fatigue usage.

Use of the methodology described above results in a conservative evaluation of the vent system design margins.

DET-04-028-3 Revision 0 3-2.167 nutggh

qv E = 27,900 ksi 1000. ,

- x a x 5 N ' '

~ ,

0 %N u N m 100.-- N --

E x CmJ  % ,

c N %

5 N .....

10. 10 2 10 3 lb" lb5 lb' Number of Cycles Figure 3-2.4-14 ALLOWABLE NUMBER OF STRESS CYCLES FOR VENT SYSTEM l

_ FATIGUE EVALUATION .

( l

'w)) l DET-04-028-3 Revision 0 3-2.168 nutggh

3-2.5 Analysis Results The geometry, loads and load combinations, acceptance criteria, and analysis methods used in the evaluation of the Fermi 2 vent system are presented and discussed in the preceding sections. The results and conclusions derived from the evaluation of the vent system are presented in the paragraphs and sections which follow.

The maximum primary membrame stresses for the major components of the vent system are shown in Table 3-2.5-1 for each of the governing loads. The corresponding l l

reaction loads for the vent system support columns and vent line-drywell penetration are shown in Tables 9l 3-2.5-2 and 3-2.5-3. The maximum differential displace-ments of the vent line bellows for the governing load cases are shown in Table 3-2.5-4 The transient response of the vent system support columns and the drywell/wetwell vacuum breaker for pool swell loads are shown in Figures 3-2. 5-1 through 3-2. 5- 3.

The maximum stresses and associated design margins for the major vent system components, component supports, and welds for the SBA II, IBA I, DBA I, DBA II, and DBA III load combinations are shown in Table 3-2. 5-5. The DET-04-028-3 O

Revision 0 3-2.169 nutagh

maximum stresses and associated design margins for the components and welds of the vent line-SRV piping pene-tration for the NOC I, SBA II, IBA I, and DBA III loao combinations are shown in Table 3-2.5-6. The maximum differential displacements and design margins for the j i

vent line bellows for the SBA II, IBA I, DBA II, and DBA  :

III load combinations are shown in Table 3-2. 5-7. The fatigue usage factors for the controlling vent system component and weld for the Normal Operating plus SBA i events, and the Normal Operating plus IBA events are j shown in Table 3-2.5-8.

The vent system evaluation results presented in the  ;

preceding paragraphs are discussed in Section 3-2.5.1. >

^

t  !

l l

i i

l 1

l t

i DET-04-028-3

' Revision 0 3-2.170  !

nut E h  :

Table 3-2.5-1 MAJOR VENT SYSTEM COMPONENT MAXIMUM MEMBRANE STRESSES FOR GOVERNING LOADS Section -2.2 1 Load Primary Membrane Stress (ksi)

Load Type Load Case Vent Vent Downcomer Number Line Header Dead Weight la 0.40 0.96 0.04 2a 0.92 1.93 0.88 Seismic 2b 1.84 3.86 1.75 3b 5.92 11.95 4.81 Pressure and Temperature 3d N/A N/A N/A Vent System 4a Discharge 6.48 9.79 4.63 j Sa-5d 2.12 3.41 1.05 Pool Swell 5e 0.02 0.32 0.74 g

6a+6d 1.12 2.04 0.88

~ ~ ~ ~

Condensation Oscillation 6bt6d 3.24 10.83 5.04 6f 0.05 0.23 -

7a 3.93 2.98 5.29 7b 0.79 0.95 1.28 Chugging 7c(6e) - - -

7d 0.10 0.36 0.01 SRV Discharge 8a 0.69 0.66 1.45 9a 6.68 1.15 0.01 Piping Reactions Note:

1. Values shown are maximums irrespective of time and location g for individual load types and may not be added to obtain load combination results.

DET-04-028-3 Revision 0 3-2.171 g gg

Table 3-2.5-2 MAXIMUM COLUMN REACTIONS FOR GOVERNING VENT: SYSTEM LOADS A

V Section 3-2.2.1 Load Designation Column Reaction Load (kips)

Load (1)

Load Type Case Direction Inside Outside Total Number Dead weight la Compression 14.59 11.46 26.05 Tension 1.72 6.24 7.96 OBE 2a Compression 1.72 6.24 7.96 Seismit.

Tension 3.44 12.48 15.92 SSE 2b Compression 3.44 12.48 15.92 Internal Pressure 3b Tension 25.94 20.64 46.58 Temperature 3d Compression 43.68 -18.79 24.89 Ve S stem 4a Tension 34.49 24.80 59.29 Tension 47.97 29.08 77.05 Pool Swell Sa-5d Compression 15.20 9.85 25.05 i l

l IBA 6a+6c Tension 6.53 7.66 14.19 i Compression 6.53 7.66 14.19 Condensation Oscillation DBA 6b+6d Compression 36.04 50.42 86.46 Tension 16.30 20.96 37.26 Chugging 7a+7b Compression 16.30 20,96 37.26 Piping Tension 0.15 6.70 6.85 Reactions Compression 0.15 6.70 6.85 Note:

1. For dynamic loads reactions are added in time, r

(

DET-04-028-3 Revision 0 3-2.172 nutp_qh

Table 3-2.5-3 MAXIMUM VENT LINE-DRYWELL PENETRATION REACTIONS FOR GOVERNING VENT SYSTEM LOADS Lo d i tio Penetration Reaction Load Load Force (kips) Moments (in-kip)

Load Type Case Number Radial Merid. Circum. Radial Merid. Circum, i

Dead Weight la 3.30 -2.70 0.00 0.00 0.00 221.70 l

OBE 2a 17.70 0.'80 1.30 8.60 122.90 148.10 SSE 2b 35.40 1.50 2.70 17.30 445.70 296.10 3b -19.70 0.80 0.00 0.00 0.00 -173.20 f"r u Temperature 3d -130.60 1.70 0.00 0.00 0.00 -3704.10 t stem 4a 46.6C 1.70 0.00 0.00 0.00 -302.70 Pool Swell Sa-5d 18.80 -2.30 0.00 0.00 0.00 135.00 g IBA 6a+6c 9.70 0.33 0.00 0.00 0.00 33.00 Oscillaticn DBA 6b+6d 31.80 3.33 0.00 0.00 0.00 129.80 Chugging 7a+7b 14.70 -1.10 4.00 156.40 482.40 12.70 R ns a -

- - 0.00 0.00 0.00 6 .60 l

DET-04-028-3 0

Revision 0 3-2.173 nutgch

Table 3-2.5-4 MAXIMUM VENT LINS BELLOWS DISPLACEMENTS FOR GOVERNING VENT SYSTEM LOADS Section 3-2.2.1 Load Differential Bellows Displacements (in)

Designation Axial Lateral Load Load Typ Nu r Compression Extension Meridional Longitudinal Dead Weight la .001 -

.004 .000 OBE 2a .011 .011 .007 .010 Seismic SSE 2b .022 .022 .014 .020 Internal Pressure 3b .132 -

.047 .000

() Temperature 3d .510 -

.175 .000 Vent System 4a .060 -

.041 .000 Discharge Pool Swell Sa-5d .048 .048 .077 .000 IBA 6a+6c .006 .003 .005 .000 Condensation Oscillation DBA 6b+6d .031 .028 .110 .000 Chugging 7a+7b .012 .012 .032 .131 Piping Reactions 9a .020 .020 .035 .000 l

Note:

1. The values shown are maximums irrespective of time for individual load types and may not be added to obtain load combination results.

DET-04-028-3 Revision 0 3-2.174 nutgqh l

Table 3-2.5-5 MAXIMUM VENT SYSTEM STRESSES FOR CONTROLLING LOAD COMBINATIONS Load Combination Stresses (ksi)

Stress SBA II I l IBA I Il} DBA I III DBA II III DBA III II TYP8 Calc. Calc.(2~ Calc. Cale j2 Calc. j Calci 2) Calc. Calc @ Calc. Cale(2)

Stress Allow. Stress Allow. Stressi Allow. Stress Allow. Stress Allow.

C0MPONENTS

,"*, U 7.44 0.26 4.77 0.16 7.16 0.25 7.82 0.27 8.23 0.16 hsRage 27.25 0.40 20.41 0.30 N/A N/A 16.44 0.24 N/A N/A Primary Membrane 15.31 0.79 11.08 0.57 16.92 0.88 17.52 0.91 18.53 0.55 Vent Local Primary Line Membrane 14.71 0.51 11.36 0.39 13.20 0.46 28.32 0.98 18.18 0.36 Prim. + Sec. 48.58 34.71 Stress Range 0.71 0.51 N/A N/A 65.51 0.96 N/A N/A M an 12.20 0.63 10.62 0.55 17.63 0.91 18.58 0.96 19.70 0.58 H er , f 24.29 0.84 12.88 0.44 23.90 0.83 24.90 0.86 28.16 0.55 Prim. + Sec.

Stress Range 61.28 0.90 44.64 0.66 N/A N/A 61.73 0.91 N/A N/A l M an 9.24 0.48 3.32 0.17 7.53 0.39 9.25 0.48 9.85 0.29 Mc r ary 13.14 0.45 9.43 0.33 18.68 0.65 21.44 0.74 19.59 0.38

,+,Sec. 36.06 0.53 21.39 0.31 N/A N/A 53.61 0.79 N/A

, N/A Support Priman 7.91 0.41 4.72 0.24 5.46 7.13

"* *"* 0.28 0.37 6.20 0.18 Column U 14.81 p , 0.51 11.15 0.39 25.42 0.88 20.25 0.70 28.23 0.55 ft s Ra 45.14 0.66 31.26 0.46 N/A N/A 33.35 0.49 373 yfg COMPONENT SUPPORTS 1

Bending 5.43 0.28 5.67 0.29 1.50 0.08 7.51 0.38 2.52 0.10 Tensile 0.52 0.03 0.14 0.01 1.48 0.08 1.42 0.07 1.52 0.06 Support Columns Combined 0.31 0.31 0.30 0.30 0.16 0.16 0.45 0.45 0.16 0.16 Compressive 0.78 0.05 0.51 0.03 0.14 0.01 0.49 0.03 '0.24 0.01 Interaction 0.41 0.41 0.46 0.46 0.16 0.16 0.54 0.54 0.16 0.16 WELDS Column Primary 1.42 0.09 Ring 1.07 0.07 2.45 0.16 1.93 0.13 2.69 0.10 a

Secondary 4.32 0.10 2.99 0.07 N/A N/A 3.18 0.07 N/A N/A DET-04-028-3 Revision 0 3-2.175 nutqqERS E h

i

/ Table 3-2.5-6 d

MAXIMUM VENT LINE-SRV PIPING PENETRATION STRESSES FOR CONTROLLING LOAD COMBINATIONS NOC I SBA II IBA I DBA III St ss Cal Cal "I

  • CalO.

Item Calc.

Calc.

Calc. Calc.

(ksi) Allow (ksi) Allow (ksi) Allow (ksi) Allow COMPONENT 5.96 0.36 8.93 0.54 8.03 0.49 8.83 0.29 Me Penetration Local Nozzle Primary 12.51 0.51 14.24 0.58 14.11 0.57 15.99 0.35 Membrane O \s Primary +

Sgcondary 45.93 0.77 46.10 0.77 45.93 0.77 N/A -

Range WELDS Nozzle Primary 3.77 0.30 4.44 0.36 3.67 0.30 4.49 0.20 to Sleeve (Upper) Secondary 33.97 0.75 35.30 0.78 33.98 0.76 N/A -

Nozzle Primary 5.70 0.46 7.82 0.63 5.78 0.47 6.45 0.28 to Sleeve (Lowe r) Secondary 40.59 0.90 44.06 0.98 39.92 0.89 N/A -

Notes:

1. Reference Table 3-2.2-25 for load combination designations.
2. Reference Table 3-2.3-1 for allowable stresses.

() DET-04-028-3 Revision 0 3-2.176 nutgqh

O Table 3-2.5-7 MAXIMUM VENT LINE BELLOWS DIFFERENTIAL DISPLACEMENTS FOR CONTROLLING LOAD COMBINATIONS l

. SBA II IBA I DBA II DBA III Displacement Component Calc. Calc. Calc. Calc. Calc. Calc. Calc. Calc.

(in) Allow. (in) Allow. (in) Allow. (in) Allow.

Compression .502 .57 .579 .66 .629 .72 .602 .69 Axial Tension -

Meridional .185 .30 .265 .42 .288 .46 .271 .43 Lateral Longitudinal .173 .28 .032 .05 .010 .02 .042 .07 Note:

1. The DBA III bellows displacements envelop those of DBA I since DBA III contains SRV discharge loads in addition to the other loads in DBA I as shown in Table 3-2. 2-25 .

DET-04-028-3 Revision 0 3-2.177 nutp_qh l

1

~

Tablo 3-2.5-8 MAXIMUM FATIGUE USAGE FACTORS FOR VENT SYSTEM COMPONENTS AND WELDS fs >

i Load Case Cycles Event Usage Factor Event Condensation (4) (5) to

. Sequence

~

(3) Oscillation Chqgina Seismic Pressure Temperature IC*I I#*I *

  • Disc rge H r NOC (2) (2)

W'/SRV Discharge 0 150 150 2804 N/A N/A .00 .36 L

SBA

0. to 600. sec 0 0 0 50 N/A 300. .19 .00 SBA 600. to 1200 see 1000(2) 1 1 2 N/A 600. .36 .01 G' IBA
0. to 330. sec 0 0 0 25 300. N/A .00 .00 IEA 300 to 500. see 1000(2) 1 1 2 N/A 200. .51 .00 NOC + SBA .55 .37 Maximum Cumulative Usage Factors NOC + IBA .51 .36 Notes:
1. See Table 3-2.2-25 and Figures 3-2.2-11 and 3-2.2-12 for load cycles and event sequencing information.
2. Entire number of load cycles conservatively assumed to occur during time of maximum event usage.
3. Total number of SRV actuations shown are conservatively assumed to occur in same suppression i

chamber bay.

4. Each chug-cycle has a duration of 1.4 sec. See rigure 3-2.2-18 for chugging downcomer load histogram. The maximum fatigue usage factor for chugging downcomer loads at the downcomer-vent header intersection is 0.24.
5. The maximum etznulative usage for a vent system component occurs in the vent header at the downcomer-vent header intersection.
6. The maximum cumulative usage for a vent system component weld occurs at the SRV piping-vent line penetration.

O V

DET-04-028-3 Revision 0 3-2.178 nutsh

O Outside Column, P = 29.08 kips mn E

.R --

6 I h 3

a 20.-- Y 3 h1 ,

a g

, MUtwh i

s l i

^

8 0.- -) Wh.Ah/Ahk i r g

i p ur+

i gy y v

~

v v, ,v c.

@' -10.-- .

m . . . . . .

O. 0.2 0.4 0.6 0.8 1.0 1.2 1.4 O

Time (sec)

Figure 3-2.5-1 VENT SYSTEM SUPPORT COLUMN RESPONSE DUE TO POOL SWELL IMPACT LOADS-OUTSIDE COLUMN DET-04-028-3 3-2.179 Revision 0 nutp_qh

O.

(>

Inside Column, P mn = 47.97 kips ac.

5 0 .-

e e

c O

A ]L e-4 4 '

L j f NAA v r c

h h L i i1 A .. _.r i_

0 .- . . m p ygg vy yry ys - v -- - -

g U

U i k4 o

C. +

0.

$ -30. , , , ,

0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 O  :

Time (sec) [

i Figure 3-2.5-2 VENT SYSTEM SUPPORT COLUMN RESPONSE DUE TO POOL SWELL IMPACT LOADS - INSIDE COLUMN I

() DET-04-028-3 Revision 0 3-2.180 i

l 1

nuttgh

  • l l

O Vacuum Breaker, A =3.08g's max 4.

2 o 2._

3 I i l i h l f

\ \

1 h [ , _ l . \  !\ l n 0 l ' ' "I I ' i .! .n h A n n 0 '

  • 1'  !! il 0 1 u i i N i l i ut W 'i MVYV

'{ )j g i ,

l 1 I l

(

g I I

$ -2. =

l I I I l l l 0 .2 .4 .6 .8 1.0 1.2 1.4 Time (sec)

{

Figure 3-2.5-3 VACUUM BREAKER RESPONSE DUE TO POOL SWELL IMPACT LOADS h DET-04-028-3 Revision 0 3-2.181 nutggh

3-2 . 5 .1 Discussion of Analysis Results The results shown in Table 3-2.5-1 indicate that the largest vent system primary membrane stresses occur for internal pressure loads, vent system discharge loads, pool swell impact loads, DBA condensation oscillation downcomer loads, and chugging downcomer lateral loads.

The remaining loadings result in small primary-stresses in the vent system major components.

Table 3-2.5-2 shows that the largest vent system support column reactions occur for internal pressure loads, vent system discharge loads, pool swell impact loads, and DBA condensation oscillation loads. The distribution of loads between the inner and outer support columns varies from._ load case to load case. The magnitude and distribution of reaction loads on the drywell penetrations also vary from load case to load case, as shown in Table 3- 2 . 5- 3. Table 3-2.5-4 shows that the dif ferential displacements of the vent line bellows are small for all loadings but thermal loadings.

The results shown in Table 3-2.5-5 indicate that the highest stresses in the vent system components, compo-nent supports, and associated welds occur for the SBA II DET-04-028-3 Revision 0 3-2.182 nutggh

and the DBA II load combinations. The vent line, vent header, and downcomer stresses for the SBA II and DBA II load combination are less than the allowable limits with stresses in other vent system components, component supports, and welds well within the allowable limits.

The stresses in the vent system components, component supports, and welds for the IBA I, DBA I, and DBA III load combinations are also well within the allowable 1

i limits.

1 The results shown in Table '-2.5-7 indicate that the vent line bellows differential displacements are all well within allowable limits. The maximum displacement occurs for the SBA II load combination.

O The loads which cause the highest number of displacement cycles at the vent line bellows are seismic loads, SRV 1

I loads, and LOCA related loads such as pool swell, condensation oscillation, and chugging. The bellows displacements for these loads are small compared to the maximum allowable displacement and their effect on fatigue is negligible. Thermal loads and internal pressure loads are the largest contributors to bellows displacements. The specified number of thermal load and internal pressure load cycles is 150. Since the bellows DET-04-028-3 e

R; vision 0 3-2.183 nutgch

i i

have a rated capacity of 500 cycles at maximum displace- $

ment, their adequacy for fatigue is assured. i t'

The vent system fatigue usage factors shown in Table

{

3-2.5-8 are computed for the controlling events, which are Normal Operating plus SBA and Normal Operating plus i

IBA. The governing vent system component for fatigue is the vent header at the downcomer-vent header inter- l t

section. The magnitudes and cycles of downcomer lateral  !

t loads are the primary contributors to fatigue at this i location. t The governing venc system weld for fatigue is the nozzle {

O to gusset weld at the SRV penetration to the vent t

line. SRV temperature and thrust loads and the number I i

of SRV actuations are the major contributors to fatigue  !

at this location'.  !

Fatigue effects at other locations in the vent system l are less severe than at those described above, due l primarily to lower stresses and a lesser number of stress cycles.

DET-04-028-3 I Revision 0 3-2.184 l nutg,gh  !

i l

_ _ _a

3-2.5.2 Closure h

The vent system loads described and presented in Section 3-2.2.1 are conservative estimates of the loads postu-lated to occur during an actual LOCA or SRV discharge event. Applying the methodology discussed in Section 3-2.4 to examine the effects of the governing loads on the vent system results in bounding values of stresses and reactions in vent system components and component supports.

The load combinations and event sequencing defined in Section 3-2.2.2 envelop the actual events postulated to g

occur during a LOCA or SRV discharge event. Combining the vent system responses to the governing loads and evaluating fatigue effects using this methodology results in conservative values of the maximum vent system stresses, support reactions, and fatigue usage factors for each event or sequence of events postulated to occur throughout the life of the plant.

The acceptance limits defined in Section 3-2. 3 are at least as restrictive, and in many cases more restric-tive, than those used in the original containment design documented in the plant's FSAR. Comparing the resulting DET-04-028-3 Revision 0 3-2.185 nutgch

O maximum stresses and support reactions to these accep- l tance limits results in a conservative evaluation of the design margins present in the vent system and vent sys- l tem supports. As is demonstrated from the results dis- '

cussed and presented in the preceding sections, all of the vent system stresses and support reactions are with-in these acceptance limits.

l 1

As a result, the components of the vent system described in Section 3-2.1, which are specifically designed for the loads and load combinations used in this evaluation, exhibit the margins of safety inherent in the original doign of the primary containment as documented in the plant's FSAR. The intent of the NUREG-0661 require-ments, as it relates to the design adequacy and safe l operation of the Fermi 2 vent system, is therefore  ;

i considered to be met. ,

P b

v I DET-04-028-3 Revision 0 3-2.186 nutggb i l

- _ . ~ . ,

'f f

l V 3-3.0 LIST OF REFERENCES l

1. " Mark I Containment Long-Term Program," Safety '

Evaluation Report, NRC, NUREG-0661, July 1980.

2. " Mark I Containment Program Load Definition Report," General Electric Company, NEDO-21888, Revision 2, December 1981. ,
3. " Mark I Containment Program Plant Unique Load Definition," Enrico Fermi Atomic Power Plant [

Unit 2, General Electric Company, NEDO-24568, Revision 1, June 1981.  ;

4. Enrico Fermi Atomic Power Plant Unit 2, Final i Safety Analysis Report (FSAR), Detroit Edison Company, Section 3.8, Amendment 12, June 1978. i i
5. " Mark I Containment Program Structural Acceptance l Criteria Plant Unique Analysis Application Guide,  !

Task Number 3.1.3," General Electric Company, NEDO-24583-1, October 1979.

r

6. ASME Boiler and Pressure Vessel Code,Section III, -

Division 1, 1977 Edition with Addenda up to and including Summer 1977.

c l

l I

DET-04-028-3 Revision 0 3-3.1  !

nutggb l

. _ . . _ .