RS-22-085, Application to Revise Design Basis to Allow Use of Plastic Section Properties in Lower Downcomer Braces Analysis

Application to Revise Design Basis to Allow Use of Plastic Section Properties in Lower Downcomer Braces Analysis

ML23013A076
Person / Time
Site:	LaSalle
Issue date:	01/12/2023
From:	Kevin L Constellation Energy Generation
To:	Office of Nuclear Reactor Regulation, Document Control Desk
References
RS-22-085
Download: ML23013A076 (1)

Text

4300 Winfield Road Constellation Warrenville, IL 60555 630 657 2000 Office RS-22-085 10 CFR 50.90 January 12, 2023 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D.C. 20555-0001 LaSalle County Station, Units 1 and 2 Renewed Facility Operating License Nos. NPF-11 and NPF-18 NRC Docket Nos. 50-373 and 50-374

Subject:

Application to Revise Design Basis to Allow Use of Plastic Section Properties in Lower Downcomer Braces Analysis In accordance with 10 CFR 50.90, "Application for amendment of license, construction permit, or early site permit," Constellation Energy Generation, LLC (CEG) is submitting a license amendment request for LaSalle County Station, Units 1 and 2 (LSCS) to revise the Updated Final Safety Analysis Report (UFSAR) to allow the use of plastic section properties in analysis of the lower downcomer braces.

The request is subdivided as follows:

- Attachment 1 provides a description and evaluation of the proposed change.

- Attachment 2 provides a markup of the affected UFSAR pages.

- Attachment 3 provides design calculation documents for information only.

A pre-application meeting with the NRC was held on November 10, 2022, to provide a summary of the proposed license amendment request, ensure a common understanding of the proposed change and scope of the planned submittal, summarize supporting analyses and activities that have been performed, and to obtain NRC feedback prior to formal submittal. NRC feedback has been incorporated into Attachment 1.

The proposed changes have been reviewed by the LSCS Plant Operations Review Committee in accordance with the CEG Quality Assurance Program.

The attachment to this letter provides a description and assessment of the proposed changes.

Approval of the proposed amendment is requested by January 31, 2024. Site implementation will occur within 30 days of NRC approval.

In accordance with 10 CFR 50.91, a copy of this application, with attachments, is being provided to the designated State Officials.

January 12, 2023 U.S. Nuclear Regulatory Commission Page 2 There are no regulatory commitments contained within this letter. Should you have any questions concerning this letter, please contact Mr. Jason Taken at (630) 657-3660.

I declare under penalty of perjury that the foregoing is true and correct. Executed on the 12th day of January, 2023.

Respectfully, Kevin y

Lueshen, Digitally signed by Lueshen, Kevin Date: 2023.01.12 14:33:10 -06'00' Kevin Lueshen Sr. Manager - Licensing Constellation Energy Generation, LLC : Description and Assessment : UFSAR Markup : Design Bases Calculations (for information only)

cc: NRC Regional Administrator, Region III NRC Senior Resident Inspector - LaSalle County Station NRC Project Managers - LaSalle Station Illinois Emergency Management Agency - Division of Nuclear Safety

ATTACHMENT 1 LaSalle County Station, Units 1 and 2 Renewed Facility Operating License Nos. NPF-11 and NPF-18 NRC Docket Nos. 50-373 and 50-374 Description and Assessment

ATTACHMENT 1 Description and Assessment

Subject:

Application to Revise Design Basis to Allow Use of Plastic Section Properties in Lower Downcomer Braces Analysis 1.0 Summary Description 2.0 Detailed Description 3.0 Technical Evaluation

3.1 Background

3.2 Methodology 3.3 Evaluation of Downcomer Bracing and Gusset Plate Sections 3.4 Load Combinations 3.5 Plastic Section Properties Justification 3.6 Potential for Structural Changes 3.7 Comparison to Other Plants 4.0 Regulatory Evaluation 4.1 Applicable Regulatory Requirements 4.2 No Significant Hazards Consideration Analysis 4.3 Conclusion 5.0 Environmental Evaluation 6.0 References

ATTACHMENT 1 Description and Assessment 1.0

SUMMARY

DESCRIPTION In accordance with 10 CFR 50.90, "Application for amendment of license, construction permit, or early site permit," Constellation Energy Generation, LLC (CEG) is submitting a license amendment request for LaSalle County Station, Units 1 and 2 (LSCS) to revise the Updated Final Safety Analysis Report (UFSAR) to allow the use of plastic section properties in analysis of the lower downcomer braces.

2.0 DETAILED DESCRIPTION During interface with the Nuclear Regulatory Commission on a non-conforming condition related to the pool swell profile, it was identified that analyses 187, 187K, and Rev. 0 of L-002547 utilize plastic section modulus, contrary to station licensing commitments (Reference 9). Calculations 187 and 187K are being revised to point to Calculation L-002547, Revision 0A (see Attachment

3) which contains updated evaluations for the upper downcomer bracing members, lower downcomer bracing members, and lower downcomer bracing gusset plates connecting the brace member to the downcomer.

The suppression chamber vent system consists of 98 downcomer pipes open to the drywell and submerged below the water level of the suppression pool, providing a flow path for uncondensed steam into the water. These downcomers function as the path for pressure suppression of steam, liquid and gases released in the drywell during a Loss of Coolant Accident (LOCA). Each downcomer has a 23.5-inch internal diameter. The downcomers project 6 inches above the drywell floor to prevent flooding from a broken line. This ensures complete quenching of the steam as it exits the downcomer pipes. Each vent pipe opening is shielded by a 1-inch-thick steel deflector plate to prevent overloading any single vent pipe by direct flow from a pipe break to that particular vent.

The downcomers in the suppression pool have been braced at elevation 721 feet, well above the pool swell impact zone, to reduce the pool dynamic loads transmitted to the drywell floor.

Additional bracing (Lower Downcomer Braces) for the downcomers is installed at elevation 697 feet to support the downcomers against bounding submerged structures loads. The downcomer vents are subjected to static and dynamic loads due to normal, upset, emergency, and faulted plant conditions.

The downcomer bracing system consists of inner and outer rings which brace the inner and outer downcomers, respectively. Both the inner and outer rings consist of upper bracing and lower bracing. The upper bracing members are built-up I shapes while the lower bracing members are 8" diameter XXS pipe sections.

The proposed changes do not affect how any systems are operated or controlled. The use of the plastic section modulus is limited to the lower downcomer bracing members and the lower downcomer gusset plate sections.

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ATTACHMENT 1 Description and Assessment

3.0 TECHNICAL EVALUATION

3.1 Background

Calculation L-002547, Revision 0A provides design basis analyses for the upper and lower downcomer braces and lower downcomer brace gusset plate sections. The scope of the calculation was to re-evaluate the downcomer bracing members and gusset plate section based on the bounding loads. For the upper downcomer bracing members, elastic section properties are used, consistent with the current licensing basis. However, for the lower downcomer bracing members and the lower downcomer gusset plate sections, the design basis allowables (AISC 7th Edition) are exceeded in (3) modeled braces when using elastic section modulus.

Therefore, the plastic section modulus is used to evaluate all lower downcomer bracing members and the lower downcomer gusset plate sections. No changes are required for the upper downcomer braces. The plastic sections modulus applies only to the lower downcomer braces and lower downcomer gusset plate sections.

3.2 Methodology The loads on the downcomer vents are put into the PIPSYS model to determine the moments and axial loads at a joint. The most heavily-loaded member is determined by comparing every member/node which has a maximum axial force or bending moment due to any of the loading cases previously mentioned. To the results of the PIPSYS run, the drag load on the brace itself is added.

Procedure Summary:

a) Calculate moments due to drag loads on lower ring bracing members.

b) Determine maximum moments and axial loads on lower bracing from the PIPSYS model results.

c) Calculate stresses on lower bracing member.

d) Design connection of lower bracing to Pedestal and downcomer vent, and connection to Containment wall.

e) Reassess downcomer vent.

f) Reassess upper bracing member.

Figures 3.1 through 3.3 below show an overview of the downcomer bracing systems and the PIPSYS models used to analyze them. Additionally, as shown in the figures below, the PIPSYS models for the inner and outer rings only consist of about one quarter of the full downcomer bracing system. These partial models provide design basis analysis for the full downcomer bracing system in the existing calculations. It is considered that the output for the partial models remains bounding for the entire downcomer bracing system. The output from the PIPSYS analyses is used in the evaluation of the downcomers and bracing.

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ATTACHMENT 1 Description and Assessment INNER RING MODEL OUTER RING MODEL

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Figure 3.1: Overview of Downcomer Bracing 3 of 11

ATTACHMENT 1 Description and Assessment

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ATTACHMENT 1 Description and Assessment

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~:7E:._~ -~ SE. D IN Figure 3.3: Downcomer Bracing Model, Outer Rings 3 & 4 This evaluation considers that the same members judged to be critical in Calc. L-002547, Rev. 0 remain critical. Therefore, only the members evaluated in Calc. L-002547 Rev. 0 are evaluated in Rev. 0A. Consistent with the existing analyses for the upper bracing members, an enveloping analysis is performed. In this evaluation, the upper bracing members are analyzed using elastic 5 of 11

ATTACHMENT 1 Description and Assessment section properties, as required by LaSalle's original licensing basis. The lower downcomer bracing members and the gusset plate section are evaluated using plastic section properties.

3.3 Evaluation of Downcomer Bracing and Gusset Plate Sections The Downcomer braces and gusset plate sections are evaluated for controlling load combinations consisting of abnormal/extreme environmental loads. The loading on these members is obtained from the PIPSYS analysis.

Conservatively, the evaluation considers a true envelope of the loads for the upper bracing members. In other words, the maximum force/moment of all upper bracing members for each case are considered to act concurrently.

Stresses are evaluated as follows:

a) Upper Downcomer Braces: Elastic section properties are used, consistent with the current licensing basis.

b) Lower Downcomer Braces and Lower Downcomer Brace Gusset Sections: Plastic Section properties are used.

3.4 Load Combinations Controlling load combinations for lower bracing members and gusset plate sections consist of abnormal/extreme environmental loads. Load combinations 7-1, 7-2 and 7-3 below were considered, where:

S = Allowable stress D = Dead loads Ta = Accident temperature load LOCA = Loss of Coolant Accident loads SRV = Safety/Relief valve load Ess = Safe shutdown earthquake Station Blackout cases (SBO) and Small Line Break LOCA cases S1 and S2:

7-1. 6'7a + SRV + Ess LOCA line break cases L3, I1b, and I2b:

7-2. 6'7a  659/2&$(ss LOCA line break cases L1, L2, I1a, I2a, and S3:

7-3. 6'7a  659/2&$(ss 3.5 Plastic Section Properties Justification Controlling load combinations for the lower bracing members and gusset plate sections consist of abnormal/extreme environmental loads similar to other high energy load combinations.

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ATTACHMENT 1 Description and Assessment High energy line breaks are discussed in Section 3.6 of the UFSAR. The discussion in this section focuses on the design of pipe whip restraints and in Table 3.6-6 acceptance criteria are provided. This table shows that the energy absorbing portions of the pipe whip restraints are allowed to go plastic, thereby absorbing energy.

Support steel for the VR Exhaust plenum walls for the Abnormal, Abnormal/Severe Environmental and Abnormal/Extreme Environmental load cases are discussed in section 3.C.5 of the UFSAR. They are designed to AISC allowables stresses increased by a factor of 1.6, however, in cases where this allowable cannot be met, the section in question can fully develop its plastic moment (Utilize plastic section modulus).

The stresses in the lower downcomer braces and lower downcomer gussets plate sections were limited to American Institute of Steel Construction (AISC) allowable stresses increased by a factor of 1.6. The maximum stresses for each were determined to be greater than elastic allowables. For the lower downcomer braces and lower downcomer gussets plate sections the stresses cause formation of a plastic hinge and the behavior is no longer elastic. Therefore, they were qualified using the plastic section modulus methodology. The computed stresses considering elastic behavior are still less than the steel ultimate strength and the calculated stresses using plastic section modulus methodology are less than the yield stress.

The downcomers function as the path for pressure suppression of steam, liquid and gases released in the drywell during a Loss of Coolant Accident (LOCA). Once Reactor Pressure Vessel (RPV) depressurization has been completed, the energy addition to the primary containment through the SRVs will be within the capacity of the containment vent, even if the SRV discharges are uncovered. Maintaining the RPV depressurized then takes priority and primary containment pressure may be controlled by venting. Therefore, second order analysis of the post blowdown deformed shape of the downcomer braces and gusset plate sections is not required.

3.6 Potential for Structural Changes Based on the evaluations performed on the downcomer braces and lower downcomer brace gusset plate sections, it is currently concluded that no structural modifications will be required.

3.7 Comparison to Other Plants LaSalle Station has reviewed the UFSAR/FSAR of other Constellation stations relative to the use of plastic section properties for structural steel members for comparison. Below in Figures 3.4 and 3.5 are excerpts from the Dresden and Quad Cities Station UFSAR, respectively.

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ATTACHMENT 1 Description and Assessment teel Members C b:e . ' Design Limit Ben ding l. 6* AI C allowable based on pla tic section modulus with. st:resse n ot to exceed 0.95 *Fy. For this t.o b u sed, the section sh ould satisfy the oompact sec..-tiun criteria a n d lateral hracing requirements of the AI C ode. A[S, LR

• D Spec..-ification may be con ulted to obtain furt h er clarifications.

Axial 1.6* AI C alluwable not <0.95*Fy h ear Figure 3.4: Dresden UFSAR Section 3.9.3.3.4.2 QUAD ITIE - UFSAR:

embers Stre Deign Limit Bending L6

• AI allowable ba ed on plastic section modulu with stres es not to exceed 0.9

• Fy. For thi to be u ed the ection hould .ati fy the compact ection criteria and lateral bracing r,equiremen t of the Al Code. LR:FD pacification may be con ulted to obtain further clarifications.

Axial L6

• AI allowable not< 0.95* Fy Shear 0 *.9 *Fy I (3)1.1.2 = 0. 48

• Fy Figure 3.5: Quad Cities UFSAR Section 3.9.3.1.3.4.2 As identified above, both Dresden and Quad Cities Station allow for the use of plastic section modulus in the design of Main Steam Piping Supports (High Energy Systems).

4.0 REGULATORY EVALUATION

4.1 Applicable Regulatory Requirements 10 CFR 50, Appendix A, "General Design Criteria for Nuclear Power Plants," Criterion 16, "Containment Design," requires that reactor containment and associated systems shall be provided to establish an essentially leak-tight barrier against the uncontrolled release of radioactivity to the environment and to assure that the containment design conditions important to safety are not exceeded for as long as postulated accident conditions require.

10 CFR 50, Appendix A, "General Design Criteria for Nuclear Power Plants," Criterion 50,

'Containment design basis," requires that the reactor containment structure, including access 8 of 11

ATTACHMENT 1 Description and Assessment openings, penetrations, and the containment heat removal system shall be designed so that the containment structure and its internal compartments can accommodate, without exceeding the design leakage rate and with sufficient margin, the calculated pressure and temperature conditions resulting from any loss-of-coolant accident. This margin shall reflect consideration of (1) the effects of potential energy sources which have not been included in the determination of the peak conditions, such as energy in steam generators and as required by § 50.44 energy from metal-water and other chemical reactions that may result from degradation but not total failure of emergency core cooling functioning, (2) the limited experience and experimental data available for defining accident phenomena and containment responses, and (3) the conservatism of the calculational model and input parameters.

10 CFR 50.59 allows licensees to make changes to the plant as described in the UFSAR only if the changes do not result in a malfunction of a structure, system, or component important to safety with a different result than any previously evaluated in the UFSAR. As discussed in Section 3.0 above, the proposed change results in a departure from a method of evaluation described in the UFSAR used in establishing the design bases or in the safety analyses.

4.2 No Significant Hazards Consideration Analysis In accordance with 10 CFR 50.90, "Application for amendment of license, construction permit, or early site permit," Constellation Energy Generation, LLC (CEG) is submitting a license amendment request for LaSalle County Station, Units 1 and 2 (LSCS) to revise the Updated Final Safety Analysis Report (UFSAR) to allow the use of plastic section properties in analysis of the lower downcomer braces.

CEG has evaluated whether a significant hazards consideration is involved with the proposed amendment(s) by focusing on the three standards set forth in 10 CFR 50.92, "Issuance of amendment," as discussed below:

1. Does the proposed amendment involve a significant increase in the probability or consequences of an accident previously evaluated?

Response: No The proposed change revises the LSCS UFSAR to allow the use of plastic section properties in analyses of the lower downcomer braces. The proposed changes do not affect plant operations or any design function. No physical plant changes are being made, so there is no change to the probability or consequence of any accident.

Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.

2. Does the proposed amendment create the possibility of a new or different kind of accident from any previously evaluated?

Response: No The proposed changes do not create the possibility of a new or different kind of accident 9 of 11

ATTACHMENT 1 Description and Assessment from any accident previously evaluated because they do not involve the addition of any new components or systems. The proposed changes do not alter the design function of components or systems that could initiate a new or different kind of accident. The proposed changes do not alter how components or systems are controlled or utilized. The methodology does not require any physical changes to the plant; therefore, no new accidents could be introduced.

No credible new failure mechanisms, malfunctions, or accident initiators not considered in the design and licensing bases are introduced. The proposed change does not invalidate assumptions made in the safety analysis.

Therefore, the proposed change does not create the possibility of a new or different kind of accident from any previously evaluated.

3. Does the proposed amendment involve a significant reduction in a margin of safety?

Response: No The changes revising the LSCS UFSAR to allow the use of plastic section properties in analyses of the lower downcomer braces do not represent a significant change in a margin of safety. The lower downcomer braces were originally designed elastically to the American Institute of Steel Constructions (AISC) Steel Construction Manual - 7th Edition allowable stresses times a factor of 1.6. In the reassessment of these members, plastic section properties are allowed for abnormal/extreme environmental load cases. It is appropriate to consider them similar to high-energy line break systems that allow plastic section properties to be utilized and will maintain their integrity as they absorb energy.

The proposed change does not adversely affect existing plant safety margins or the reliability of the equipment assumed to operate in the safety analysis. As such, there are no changes being made to safety analysis assumptions, safety limits, or limiting safety system settings that would adversely affect plant safety as a result of the proposed change.

Therefore, the proposed change does not involve a significant reduction in a margin of safety.

Based on the above, CEG concludes that the proposed change presents no significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of "no significant hazards consideration" is justified.

4.3 Conclusion In conclusion, based on the considerations discussed above, (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commissions regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

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ATTACHMENT 1 Description and Assessment 5.0 ENVIRONMENTAL EVALUATION The proposed change would not change a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, or would change an inspection or surveillance requirement. The proposed change does not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluents that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure. Accordingly, the proposed change meets the eligibility criterion for categorical exclusion set forth in 10 CFR 51.22(c)(9).

Therefore, pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the proposed change.

6.0 REFERENCES

1. AISC Manual of Steel Construction, 7th Edition

2. LaSalle Updated Final Safety Analysis Report, Rev. 025

3. Dresden Updated Final Safety Analysis Report, Rev. 014

4. Quad Cities Updated Final Safety Analysis Report, Rev. 016

5. Calculation L-002547, ASSESSMENT OF CONTAINMENT WALL, BASEMAT, LINER, REACTOR PEDESTAL, DOWNCOMER BRACING, DRYWELL FLR, SUPP. POOL CO.,

FOR 105% PWR UPRATE, Rev. 0A

6. Calculation 187, DESIGN DOWNCOMER BRACING EL697'1", Rev. 1A

7. Calculation 187K, ASSESSMENT DOWNCOMER BRACING SYS LOADS, Rev. 0A

8. "Request for License Amendment to revise the basis for evaluation of VR Exhaust Plenum Masonry Walls for LaSalle Units 1 and 2," dated May 5, 1999 (ML20206J692)

9. Integrated Inspection Report 373/374/2017004, dated 2/13/18 11 of 11

ATTACHMENT 2 LaSalle County Station, Units 1 and 2 Renewed Facility Operating License Nos. NPF-11 and NPF-18 NRC Docket Nos. 50-373 and 50-374 UFSAR Markup

Proposed Change:

01213 45167 Revise section, delete text with strikethrough and add the following text at bullet point b.

899899ÿÿ7ÿ The allowable stresses for the downcomer bracing are:

9ÿÿ ÿ ÿ! 1. The AISC allowables, for load combinations 1, 2, and 3 of Table 4.1-1.

"9ÿÿ #ÿ ÿ$! 2. 1.6 times AISC allowables based on elastic** section

9ÿÿ  ÿÿ%ÿ!ÿ% modulus, but no greater than 0.95 fy, for load combinations 4, 4A, 5, 5A, 6, 7 and 7A.

9ÿÿ &ÿ ÿ$9 **Lower downcomer braces and gusset plate sections may utilize plastic section modulus for load cases 7 and 7A.

899899'ÿÿ7ÿ1( Refer to DAR section 5.3.3.4 for the downcomer bracing

9ÿÿ 8ÿ ÿ'ÿÿapplicable

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ATTACHMENT 3 LaSalle County Station, Units 1 and 2 Renewed Facility Operating License Nos. NPF-11 and NPF-18 NRC Docket Nos. 50-373 and 50-374 Design Bases Calculations (for information only)

CC-AA-309-1001-F-01 Revision O Page 1 of 1 Design Analysis Cover Sheet Form p age 1 Design Analysis I Last Page No.

• 100 Analysis No.: 1 L-002547 Revision: 2 DA Major D Minor~

Title:

3 Assessment of Containment Wall, Basemat, Liner, Reactor Pedestal, Downcomer Bracing, Drywell Floor, and Suppression Pool Columns for 105% Power Uprate EC No.:* 634630 Revision:

• 0 Station(s): 1 LAS Component(s): "

Unit No.:

• 1&2 Discipline:

• STDC Descrip. Code/Keyword: 10 S02 Safety/QA Class: 11 SR System Code: 12 MS Structure: 13 RB CONTROLLED DOCUMENT REFERENCES 1 Document No.: From/To Document No.: From/To Cale. 187 From Cale 187K From I

- *-; 42--')) 1.1.\,\-L1.. From Is this Design Analysis Safeguards Information? 1* Yes No~ If yes, see SY-AA-101-106 Does this Design Analysis contain Unverified Assumptions? 11 YesO No~ If yes, ATI/AR#:

This Design Analysis SUPERCEDES: 1

• N/A in its entirety.

Description of Revision (list changed pages when all pages of original analysis were not changed): 1*

Minor revision DA assesses the feasbility of qualifying the downcomer bracing members using the elastic section modulus, consistent with the current licensing commitment. If not feasible, the analysis is updated to use the plastic section modulus in support of a License Amendment Request.

Preparer: 20 See Page 1.1 Print Name Sien Name Date Method of Review: 21 Detailed Review R Alternate Calculations (attached) D Testing D Reviewer: See Page 1.1 lZi 22 PrintName Sign Name Date Review Notes: 23 Independent review Peer Jeview D (For External Analyses Only)

External Approver: K. Ata ~

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• 10/11/2021

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Exelon Reviewer: ,. Qo\,4<~ ~ ~*ld rint Name

',\ ;;1,2-2 1 Date l Independent 3 rd Party Review Reqd? 2 Yes No ~

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Exelon Approver: 21

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Print Name /I Sien Name Date V

Analysis No. L-002547 Revision No: OA Paae No. 1.1 List of Preparers and Reviewers Section(s): 1.0-6.2 Prepared by: G. Frazee I ~~ I 10/11/2021 Print Name Sign N a m e ~ Date Prepared by: A. Blomguist I ~"4~11 I 10/11/2021 Print Name Sign Name Date Reviewed by: S. G. Kwon I .%!UUf~~ I 10/11/2021 Print Name Sign Name Date Method of Review: 15<1 Detailed n Alternate n Test Section(s): 7.0-7.2.6.4, 8.0-8.2 Prepared by: G. Frazee I ,tiL-~

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I 10/11/2021 Print Name Sign Name Date Reviewed by: A. Blomguist Print Name I tt. ~,.;If Sign Name I 10/11/2021 Date Method of Review: 15<1 Detailed n Alternate n Test Section(s): 7.3-7.4.4 Prepared by: A. Blomguist I ~~.;If I 10/11/2021 Print Name Sign Name Date Reviewed by: G. Frazee I ,tiL-~ I 10/11/2021 Print Name Sign N a m e ~ Date Method of Review: 15<1 Detailed n Alternate n Test

CC-AA-103-1003 Revision 15 Page 7 of 18 ATTACHMENT 2 Owner's Acceptan ce Review Checklist for External Design Analyses Page 1 of 3 Design Analysis No.: L-002547 Rev: 0A Page 1.2 Contract# : 00597084 Release #: 00722 No Question Instructions and Guidance Yes/ No/ N/A 1 Do assumptions have All Assumptions should be stated in clear terms with enough sufficient documented justification to confirm that the assumption is conservative . §tJ rationale?

For example, 1) the exact value of a particular parameter may not be known or that parameter may be known to vary over the range of conditions covered by the Calculation. It is appropriate to represent or bound the parameter with an assumed value. 2) The predicted performance of a specific piece of equipment in lieu of actual test data. It is appropriate to use the documented opinion/position of a recognized expert on that equipment to represent predicted equipment performance.

Consideration should also be given as to any qualification testing that may be needed to validate the Assumptions. Ask yourself, would you provide more justification if you were performing this analysis? If yes, the rationale is likely incomplete.

Are assumptions Ensure the documentation for source and rationale for the 2 compatible with the assumption supports the way the plant is currently or will be ~

way the plant is operated post change and they are not in conflict with any operated and with the design parameters. If the Analysis purpose is to establish a licensing basis? new licensing basis, this question can be answered yes, if the assumption suooorts that new basis.

3 Do all unverified If there are unverified assumptions without a tracking assumptions have a mechanism indicated, then create the tracking item either ~

tracking and closure through an A Tl or a work order attached to the implementing mechanism in place? WO. Due dates for these actions need to support verification prior to the analysis becoming operational or the resultant plant change being op authorized.

4 Do the design inputs The origin of the input, or the source should be identified and have sufficient be readily retrievable within Exelon's documentation system.

&l rationale? If not, then the source should be attached to the analysis. Ask yourself, would you provide more justification if you were performing this analysis? If yes, the rationale is likely 5 Are design inputs incomplete. I The expectation is that an Exelon Engineer should be able to correct and reasonable clearly understand which input parameters are critical to the

~

with critical parameters outcome of the analysis. That is, what is the impact of a identified, if change in the parameter to the results of the analysis? If the appropriate? impact is large, then that parameter is critical.

6 Are design inputs Ensure the documentation for source and rationale for the compatible with the inputs supports the way the plant is currently or will be

.egi way the plant is operated post change and they are not in conflict with any operated and with the design parameters.

licensing basis?

CC-AA-10 3-1003 Revision 15 Page 8 of 18 ATTACHM ENT 2 Owner's Acceptance Review Checklist for External Design Analyses Page 2 of 3 Design Analysis No.: L-002547 Rev: OA Page 1.3 No Question Instructions and Guidance Yes/No/N /A 7 Are Engineering See Section 2.13 in CC-AA-309 for the attributes that are @)

Judgments clearly sufficient to justify Engineering Judgment. Ask yourself, documented and would you provide more justification if you were performing iustified? this analysis? If yes the rationale is likely incomplete.

8 Are Engineering Ensure the justification for the engineering judgment Judgments compatible supports the way the plant is currently or will be operated E

with the way the plant is post change and is not in conflict with any design operated and with the parameters. If the Analysis purpose is to establish a new licensing basis? licensing basis, then this question can be answered yes, if the judgment suooorts that new basis.

9 Do the results and Why was the analysis being performed? Does the stated conclusions satisfy the purpose match the expectation from Exelon on the proposed 01 purpose and objective of application of the results? If yes , then the analysis meets the Desian Analvsis? the needs of the contract.

10 Are the results and Make sure that the results support the UFSAR defined conclusions compatible system design and operating conditions, or they support a l8ll with the way the plant is proposed change to those conditions. If the analysis operated and with the supports a change, are all of the other changing documents licensina basis? included on the cover sheet as impacted documents?

11 Have any limitations on Does the analysis support a temporary condition or the use of the results procedure change? Make sure that any other documents ~

been identified and needing to be updated are included and clearly delineated in transmitted to the the design analysis. Make sure that the cover sheet appropriate includes the other documents where the results of this oraanizations? analysis provide the input.

12 Have margin impacts Make sure that the impacts to margin are clearly shown been identified and within the body of the analysis. If the analysis results in ,5' documented reduced margins ensure that this has been appropriately appropriately for any dispositioned in the EC being used to issue the analysis.

negative impacts (Reference ER-AA-2007)?

13 Does the Design Are there sufficient documents included to support the Analysis include the sources of input, and other reference material that is not f!5fJ applicable design basis readily retrievable in Exelon controlled Docu ents?

14 documentation?

Have all affected design 1

Determine if sufficient searches have been performed to analyses been identify any related analyses that need to be revised along 12P documented on the with the base analysis. It may be necessary to perform Affected Documents List some basic searches to validate this.

(AOL) for the associated Confiauration Chanae?

15 Do the sources of inputs Compare any referenced codes and standards to the current and analysis design basis and ensure that any differences are reconciled.

(g methodology used meet If the input sources or analysis methodology are based on committed technical and an out-of-date methodology or code, additional reconciliation regulatory may be required if the site has since committed to a more reauirements? recent code

CC-AA-10 3-1003 Revision 15 Page 9 of 18 ATTACHM ENT 2 Owner's Acceptance Review Checklist for External Design Analyses Page 3 of 3 Design Analysis No.: L-002547 Rev: OA Page 1.4 No Question Instructions and Guidance Yes I No/ N/A 16 Have vendor supporting Based on the risk assessment performed during the pre-job technical documents brief for the analysis (per HU-AA-1212), ensure that ~

and references sufficient reviews of any supporting documents not provided (including GE DRFs) with the final analysis are performed.

been reviewed when necessarv?

17 Do operational limits Ensure the Tech Specs, Operating Procedures, etc. contain support assumptions operational limits that support the analysis assumptions and _;gr and inputs? inputs.

List the critical characteristics of the product, and validate those critical characteristics.

18.

Create an SFMS entry as required by CC-AA-4008. SFMS Number: 1 1-. 4 -~8

FORM PI-EXLN-003-3 Revision 0 Analysis No. L-002547, Revision 0A Page 1.5 Licensed Engineer Certification Page Page 1 of 1 CERTIFICATION OF CALCULATION NUMBER(s): L-002547, Revision 0A I certify that the Calculation(s) listed above was prepared by me or under my personal supervision or developed in conjunction with the use of accepted engineering standards and that I am a Licensed Structural Engineer under the laws of the State of Illinois.

Certified by: -~~,c;...._~=.=.,j#._~....

< ~~;.__,~A,,....,,.,_J_ Date: 10/11/2021 Seal Below Expires: _ 1.....1/_1_0 /___

z z.

Sargent & Lundy LLC Illinois Department of Professional Regulation Registration Number is: 184-000106

Analysis No. L-002547 Revision No. OA Page2 TABLE OF CONTENTS SECTION SUB-PAGE PAGE NO.

NO.

DESIGN ANALYSIS COVER SHEET FORM 1 LIST OF PREPARERS AND REVIEWER S 1.1 OWNER'S ACCEPTAN CE REVIEW CHECKLIS T FOR EXTERNAL DESIGN ANALYSES 1.2-1.4 LICENSED ENGINEER CERTIFICATION PAGE 1.5 TABLE OF CONTENTS 2

1.0 BACKGROUND

, PURPOSE & SCOPE 3 2.0 DESIGN INPUTS 4-8 3.0 ASSUMPTI ONS & ENGINEERING CONSIDERATIONS 9 4.0 REFERENC ES 10 5.0 IDENTIFICATION OF COMPUTE R PROGRAM S 11 6.0 METHODO LOGY & ACCEPTAN CE CRITERIA 12-25 7.0 NUMERICA L ANALYSIS 26-95 8.0 RESULTS & CONCLUSIONS96-100

Analysis No. L-002547 Revision No. OA Page3

1.0 BACKGROUND

, PURPOSE & SCOPE

1.1 BACKGROUND

During Exelon's interface with the NRC on a non-conforming condition related to the pool swell profile, it was identified that analyses 187 (Ref. 3a), 187K (Ref. 3b), and Rev. 0 of L-002547 (Ref.

3c) utilize plastic section modulus, contrary to station licensing commitments. See IR No.

04091810.

Note that Rev. 0 of Cale. L-002547 (Ref. 3c) is the major calculation revision corresponding to this minor revision. Throughout this minor revision Rev. 0 of Cale. L-002547 will be referred to as "Cale. L-002547." This analysis is in support of EC 634630.

1.2 PURPOSE The purpose of this minor revision is to provide a bounding evaluation for the upper and lower downcomer brace members and lower downcomer brace gusset plate section used at some connections to the downcomers and to re-evaluate these items to bring the analysis into alignment with current station licensing commitments. As part of this effort, it was identified that incorrect bounding loads were considered in the latest analyses of the upper and lower bracing members in Cale. L-002547 (Ref. 3c). The refined analysis considering the correct bounding loads and using the elastic section modulus determined the stresses exceed the DB allowables. Therefore, Exelon is pursuing a License Amendment Request (LAR) via Licensing Action LI-21-0215 to allow for the use of plastic section modulus for the lower downcomer bracing and gusset plate section.

Based on the above, the purpose of this minor revision is to re-evaluate the lower downcomer bracing and gusset plate section using plastic section modulus in support of the LAR. The upper downcomer bracing members are evaluated using elastic section properties, consistent with the current licensing basis.

1.3 SCOPE The scope of this minor revision is to re-evaluate the downcomer bracing members and gusset plate section based on the bounding loads. For the upper downcomer bracing members, elastic section properties are used, consistent with the current licensing basis. For the lower downcomer bradcg members and the gusset plate section, plastic section moqulus is used in support of the ~R. I

Analysis No. L-002547 Revision No. OA Page4 2.0 DESIGN INPUTS ORIGIN= I Starting ordinal for matrix operations

1. Lower Downcomer Braces:

The lower downcomer bracing system (Elevation 697'-1") is shown on Dwg. 5-797 (Ref. 2a) and the bracing members are described in Section 5.3.3.1 of the Mark II Design Analysis Report (DAR) (Ref. le). As shown in Ref. 2b, the lower braces are 8" XXS pipe conforming to ASTM A618 Type II.

A corrosion allowance was originally made for the braces per Section 2.5 of Cale. 187 (Ref.

3a). The corrosion allowance only considered a design life of 40 years. Operating licenses for LaSalle Units 1 and 2 have been renewed resulting in an extended operating life of 60 years. Based on discussion with Exelon on 5/18/2020 , the reduction in thickness for an operating life of 40 years is to be used herein.

mil redcorr := I - Corrosion reduction (Ref. 3a, Section 2.5) yr Din.nom := 6.875in Nominal inner diameter of 8" XXS pipe (Ref. 3a, Section 2.5)

Dout.nom := 8.625in Nominal outer diameter of 8" XXS pipe (Ref. 3a, Section 2.5) 0 out.corr := 0 out.nom - 2*redcorr*(40yr) = 8.545 in Reduced outer diameter to account for corrosion over operating life 4

lib := 152in Moment of inertia of 8" XXS pipe, allowing for corrosion (Ref.

3a, Section 2.5) 3 Stb := 35.58in Elastic section modulus of 8" XXS pipe, allowing for corrosion (Ref. 3a, Section 2.5) 3

_n_in_.n_o_m_ = 49.83 in3 Plastic section modulus of 8" XXS pipe, allowing for 6 corrosion (Ref. 4a, page 6-27) 2 Alb := 20.23in Cross-sectional area of 8" XXS pipe, allowing for corrosion (Ref.

3a, Section 2.5)

Analys is No. L-002547 Revision No. OA Page 5 Material properties for the braces are given below. Since the maximum tempera ture considered for the Suppression Pool is 212°F per Cale. L-002547 (Ref. 3c), the yield stress of the material does not need to be reduced per Table X.1 cf Ref. 4b.

Fy.A618 := 50ksi Yield strength of ASTM A618, Type II pipe (Ref. Ga, Table 2)

2. Upper Downcomer Braces:

The upper downcomer bracing member s (Elevation 721'-0") are described in Section 5.3.3.1 and Figure 5.3-1 of the DAR (Ref. le) and in Refs. 2c and 2d. A portion of Ref. 2d is reproduced below for reference showing the dimensions of the brace web and flanges.

/

Figure 2.1-1: Upper Downoomer Bracing Plate Dimensions (Ref. 2d)

Section 2.10.2 of Ref. 3a calculates the section properties for the upper brace members 2

At.uh := 35.81in Total area of cross section 3

sx.uh := 294.47in Elastic section modulus of major axis bending 3

Sy.uh := 52.63in Elastic ~ection modulus for minor axis bending As discussed in Ref. le, the upper braces are made from ASTM A-572 Grade SO steel.

Material properties for the upper braces are shown below. As noted in Design Input

1. 1, the yield stress of the material does not need to be reduced for the design tempera tures considered.

Fy.AS72 := 50ksi Yield stress of ASTM A572 Gr 50 (Ref. 6b, Table 3)

Analysis No. L-002547 Revision No. OA Page6

3. Lower Downcomer Brace Gusset Plate:

Some of the lower downcomer brace vent connections utilize gusset plates as shown in Detail E and Detail Hon Dwg. 5798 (Ref. 2b). Note that on page 2 of Section 2.8.2 of Cale.

187 (Ref. 3a), it is stated that this gusset plate configuration is not used on any single brace-to-downcomer connections and is only used in some locations where more than one brace connects to one horizontal gusset plate on the downcome r (see Figure 2.1-2).

Section 7-7 on Ref. 2b shows the gusset plate configuration which has been reproduced in Figure 2.1-2. Although the 2 and 3 brace to vent connections use a single horizontal gusset plate, the effective section properties are considered to be the same as the single brace to vent connection. This is consistent with the existing evaluations as stated on page 3 of Section 2.8.2 of Cale. 187 (Ref. 3a).

5E:CTION 7-7

~*14,1~ 0* D~TAIL E-C0Nt-lE:C710N Of- T'IIO e.@CINO t.1£:MeiE1t~

TO te1N6' It. WITl-4 Cf~~T it Figure 2.1-2: Lower Downcomer Gusset Plate Dimensions (Ref. 2b)

The properties of the plus shaped gusset section are calculated on page 1 of Section 2.8.2 of Cale. 187 (Ref. 3a). However, the properties given there did not take the reduction in plate dimensions to account for corrosion that was considered for the lower bracing members. Considering, the gusset plates are submerged like the lower bracing members, the section properties are recalculated considering the same reduction for corrosion used for the lower bracing members.

tgp := lin-2-redc orr'(40yr ) = 0.92in Thickness of gusset plates wgp := I I in - 2* redcorr' ( 40yr) = II 0.92 in Width of gusset plates in each direction!

Agp := (2*Wgp - tgp)*tgp = 19.25 in2 Area of effective gusset section Elastic section modulus of effective gusset section Plastic section modulus of effective gusset section

Analysis No. L-002547 Revision No. OA Page7 Per Dwg. 5-797 (Ref. 2a) all plates shall be ASTM A588 (Ref. 6c) Lukens Fineline U.N. As noted in Design Input # 1, the yield strength of the material does not need to be reduced for the design temperatures ronsidered.

Fy.A5 88 := 50ksi Yield strength for gusset plate material per Table 2 in ASTM A588 (Ref. 6c)

4. Thermal load increase factors:

Cale. L-002547 (Ref. 3c) accounts for the 105% power uprate, which only increases the aa:ident thermal loading on the braces. Thermal loads from Calculation 187 (Ref. 3a) and Calculation 187K (Ref. 3b) are factored based on the design basis accident temperatures and the accident temperatures associated with the 105% power uprate. The same factors from Ref. 3c are used in this evaluation to increase the applicable thermal loads on the braces for the 190°F and 212°F accident temperatu re cases. Ref. 3c qualified the 150°F cases through engineering judgment so did not determine an increase factor for this temperatu re. However, since plastic section properties were used in the evaluations that the engineering judgment is based on, the bracing members are evaluated for the 150°F cases.

An increase factor for the 150°F temperatu re is determined following the same methodology presented in Ref. 3c.

(150 - 70)A°F IF 150 := - - - - - = 1.05 Thermal load increase factor for 150°F aa:ident (146 - 70)A°F temperatu re (Ref. 3c, Section 7)

IF190 := 1.58 Thermal load increase factor for 190°F aa:ident temperatu re (Ref. 3c, Section 7)

IF212 := 1.87 Thermal load increase factor for 212°F aa:ident temperatu re (Ref. 3c, Section 7)

5. As-built eccentricities for lower bracing members:

Section 3.4 of Cale. 187 (Ref. 3a) evaluates the lower bracing members for nonconformances with installation tolerances, which results in eccentricity between the brace centerline and the ronnection workpoint. This eccentricity results in additional moment on the brace members.

The PIPSYS model used to determine brace loads are partial mcx:lels meant to bbund all brace members. Therefore, the critical model members that are evaluated rorrespond to multiple installed brace members. Only the ea:entricity for the modeled members that are critical are considered. The critical members are considered to remain the same as those evaluated in Section 7.3 of Cale. L-002547 (Ref. 3c). Section 3.4, Pages 48-51 of Ref. 3a provide the as-installed eccentricities, which are summarized on the following page.

Analysis No. L-002547 Revision No. OA Pages elb.86.h := 0.70in Max horizontal eccentricity for inner ring model member 86 (no vertical eccentricity exists) (Unit 1 CBI brace 52) elb.l26i.h := 0.75in Max horizontal eccentricity for inner ring model member 126 (no vertical eccentricity exists) (Unit 1 CBI brace 52) (Unit 1 CBI brace 14) elb.47 := 0.0in Max eccentricity for inner ring model member 47 (No eccentricities) elb.57.h := 3.20in Max horizontal eccentricity for inner ring model member 57 (no vertical eccentricity exists) (Unit 1 CBI brace 52) (Unit 1 CBI brace 3) elb.7 := 0.06in Max eccentricity for inner ring model member 7 (Unit 1 CBI brace 20) elb.75.h := 0.70in Max horizontal eccentricity for inner ring model member 75 (no vertical eccentricity exists) (Unit 1 CBI brace 52) (Unit 2 CBI brace 2) elb.104 := 0.0in Max eccentricity for outer ring model member 104 (No eccentricities) elb.l26o := 0.0in Max eccentricity for outer ring model member 126 (No eccentricities) elb.40 := 0.25in Max eccentricity for outer ring model member 40 (Unit 1 CBI brace 40) elb.41 := 0.65in Max eccentricity for outer ring model member 41 (Unit 1 CBI brace 59) elb.67 := l .06in Max eccentricity for outer ring model member 67 (Unit 1 CBI brace 35) elb.101 := 0.0in Max eccentricity for outer ring model member 101 (No eccentricities)

Analysis No. L-002547 Revision No. DA Page9 3.0 ASSUMPTIONS & ENGINEERING CONSIDERATIONS There are no unverified assumptions used in the preparation of this analysis.

Minor engineering judgment s, where used, are identified and substantiated.

Analysis No. L-002547 Revision No. OA Page 10

4.0 REFERENCES

1. LaSalle Station Documents

a. UFSAR, Rev. 24.

b. DS-SE-01-LS, Rev. 8, "Structural Department Project Design Criteria."

c. Mark II Design Analysis Report, Rev. 10.

2. LaSalle Station Drawings

a. S-797, Rev. E, "Reactor Containment - Downcomer Bracing Plans, Sections & Details."

b. S-798, Rev. D, "Reactor Containment - Downcomer Bracing Section & Details."

c. S-869, Rev. D, "Reactor Containment Downcomer Bracing Plan & Details."

d. S-870, Rev. B, "Reactor Containment Downoomer Bracing Sections & Details."

3. LaSalle Station Calculations

a. 187, Rev. 1, "Design of Downoomer Bracing El. 697'-l"."

b. 187K, Rev. 0, "Assessment of Downcomer Bracing System for NU REG Lateral Chugging Loads."

c. L-00254 7, Rev. 0, "Assessment of Containment Wall, Basemat, Liner, Reactor ~destal, Downcomer Bracing, Drywell Floor, and Suppression Pool Columns for 105% Fower Uprate.

d. L-001799, Rev. 0, "Assessment of Containment Wall, Base Mat, Liner, Reactor ~destal, Downcomer Bracing, Drywell Floor and Suppression Fool Columns for Suppression Pool Temperature Increase."

e. 187B, Rev. 0, "Downcomer Bracing System Analysis with Additional Bracing at El. 697'-1" (Microfiche)."

4. American Institute of Steel Construction

a. Steel Construction Manual, 7th Edition.

b. Design Guide 19, "Fire Resistance of Structural Steel Framing."

5. American Society of Mechanical Engineers

a. Boiler & Pressure Vessel Code, Section III, Division 1, Subsection NC, "Class 2 Components," 1977 Edition.

b. Cases of ASME Boiler and Pressure Vessel Code, Case N-71-7 (1644-7), "Additional Material for Component Supports, Section III, Division 1, Subsection NF Class 1, 2, 3, and MC Component Supports."

6. ASTM Internatio nal

a. ASTM A618-74, "Hot-Formed Welded and Seamless High-Strength Low-Allow Structural Tubing."

b. ASTM A572-75, "High-Strength Low-Alloy Columbium-Vanadium Steels of structural Quality." 1

c. ASTM A588-81, "High-Strength Low-Alloy Structural Steel with 50 ksi Minimum Yield Point to 4 in. Thick."

7. Not Used.

8. US Nuclear Regulatory Commission

a. NUREG-0808, "MARK II Containment Program Load Evaluation and Acceptance Criteria."

b. NUREG-0800, Section 3.6.2, Rev. 1, "Determination of Rupture Locations and Dynamic Effects Associated with the Postulated Rupture of Piping."

Analysis No. L-002547 Revision No. OA Page 11 5.0 IDENTIFICATION OF COMPUTER PROGRAMS Listed below are the oomputer programs that have been used in the development of this calculation. All software listed is validated per Sargent & Lundy Software Verification &

Validation procedures, which meet 10 CFR 50 Appendix B quality assurance requirements. The software has been accessed from the LAN by the following PC numbers:

• PL10996 (G. Frazee)

• PL12327 (A. Blomquist) 5.1 MATHCAD v15.0 M050 (S&L PROGRAM NO. 03. 7.548-15_M050)

Mathcad Version 15 is a Windows-based, general purpose calculation package with built-in mathematical functions, operators, units, and constants that can be used to perform calculations.

Analysis No. L-002547 Revision No. OA Page 12 6.0 METHODOLOGY & ACCEPTANCE CRITERIA 6.1 METHODOLOGY Methodology for evaluating the downcomer braces in the existing design basis evaluations is described in Cale. 187 (Ref. 3a), Section 1.3, and is followed unless noted otherwise. Excerpts are repeated below for reference:

The loads on the downcomer vents... are put into the PIPSYS model to determine the moments and axial loads at a joint. The most heavily-loaded member is determined by comparing every member/node which has a maximum axial force or bending moment due to any of the loading cases previously mentioned. To the results of the PIPSYS run, the drag load on the brace itself is added.

Procedure Summary:

a. Calculate moments due to drag loads on lower ring bracing members.

b. Determine maximum moments and axial loads on lower bracing from the PIPSYS model results.

c. Calculate stresses on lower bradng member.

d. Design connection of lower bracing to Pedestal and downcomer vent, and connection to Containm ent wall.

e. Reassess downcomer vent.

f. Reassess upper bracing member.

Figures 6.1-1 through 6.1-3 show an overview of the downcomer bracing systems and the PIPSYS models used to analyze them.

The downcomer bracing system consists of inner and outer rings which brace the inner and outer downcomers, respectively. Both the inner and outer rings consist of upper bracing (EL 721'-0") and lower bracing (EL. 697'-11"). The upper bracing members are built-up I shapes while the lower bracing members are 8 11 diameter XXS pipe sections.

As shown in Figure 6.1-1, the PIPSYS models for the inner and outer rings only consist of about one quarter of the full downcomer bracing system. These partial models provide design basis analysis for the full downcomer bracing system in the existing calculations. It is considered that the output for the partial models remains bounding for the entire downcomer bracing system.

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5 (O,O,O) X Figure 6.1-2: Downcomer Bracing Model, Inner Rings 1 & 2 (Ref. 3a, Section 2.1)

Analysis No. L-002547 Revision No. OA Page 15 Figure 6.1-3: Downcomer Bracing Model, Outer Rings 3 & 4 (Ref. 3a, Section 2.1)

Analysis No. L-002547 Revision No. OA Page 16 The output from the PIPSYS analyses is used in the evaluation of the downcomers and bracing.

Section 2 of Cale. 187 (Ref. 3a) performed the original design basis evaluations for the bracing.

Section 3.4 of Cale. 187 re-evaluates the bracing for as-built conditions that include nonconformances with erection tolerances. These as-built conditions result in eccentricity between the centerline of the brace member and the connection work points which induces additional moment on the members. Section 4.0 of Cale. 187 re-evaluates the bracing for updated PIPSYS model runs and resulting brace loads. Throughout the original design basis evaluation, plastic section properties are considered for the lower bracing members when the use of elastic section modulus is not successful in qualifying the member. The upper bracing members are qualified through elastic analysis.

Calculation 187K (Ref. 3b) re-evaluates the downcomer bracing for revised Loss-Of-Coolant Accident {LOCA) Chugging load conditions specified in NUREG-0808 (Ref. Sa). Only the LOCA Chugging Lateral loads are changed as a result of this analysis (LOCA Chugging Drag loads remain the same as in Cale. 187). The downcomer braces were evaluated in Section 6 of Ref.

3b, and the plastic section modulus is used in the existing qualification of the lower bracing. The upper bracing members, however, are qualified through elastic analysis.

Calculation L-002547 (Ref. 3c) determines the governing loading condition (Cale. 187 or Cale.

187K loads) for the members and factors up the corresponding thermal loads to account for the 105% power uprate. The bracing members/nodes determined to be critical in Calculations 187 (Ref. 3a) and 187K (Ref. 3b) were subsequently considered to be critical in the power uprate evaluations in Cale. L-002547. The lower bracing members were qualified using plastic section modulus. The upper bracing members were qualified through using elastic section modulus.

However, through review of the Cale. 187 and Cale. 187K loads, it was determined that Cale.

L-002547 incorrectly identified the controlling loads for both the upper and lower bracing members. Therefore, they need to be re-evaluated using the correct bounding loads.

This evaluation considers that the same members judged to be critical in Cale. L-002547 (Ref.

3c) remain critical. Therefore, only the members evaluated in Cale. L-002547 are evalua:ed in this evaluation. Consistent with the existing analyses for the upper bracing members, an enveloping analysis is performed. In this evaluation, the upper bracing members are analyzed using elastic section properties, as required by LaSalle's original licensing basis. The lower downcomer bracing members and the gusset plate section are evaluated using plastic section properties, as allowed per Licensing Action LI-21-0215.

For each critical member, the loads from Cale. 187 (Ref. 3a) and Cale. 187K (Ref. 3b) are compared to determine which are governing. Consistent with Cale. L-002547 (Ref. 3c), the thermal loads are factored to account for the increased power uprate accident temperature s and combined with these governing loads following the load combinations outlined in Section 6.1.2. I The technical approaches utilized in Cale. L-002547 are used in this evaluation unless stated otherwise.

Analysis No. L-002547 Revision No. OA Page 17

6. 1. 1 Governing Loads As discussed above, Section 7 of Cale. L-002547 (Ref. 3c) determines whether Cale. 187 (Ref.

3a) or Cale. 187K (Ref. 3b) provides the governing loads. Cale. L-002547 did this by comparing the controlling margin factors from each calculation, which is not always appropriate since different approaches/methods were used in determining the margin factors. Review of the loads from the two calculations shows that the governing loads were incorrectly determined for both the upper and lower bracing members.

Consistent with the existing evaluations in Ref. 3a, Ref. 3b, and Ref. 3c, the lateral plus drag chugging loads are considered governing over other LOCA loads.

6.1.1.1 Governing Loads for Lower Bracing Members Section 7 of Cale. L-002547 determines that the original design basis evaluations in Cale. 187 (Ref. 3a) control for the lower bracing members. This is not correct for all of the critical lower bracing members that are evaluated in Cale. L-00254 7. Review of the loads from Cale. 187 and Cale. 187K shows that for some of the critical members, the loads in Cale. 187K are governing and should have been used in the evaluation. For each of the critical lower bracing members evaluated in Cale. L-002547, the loads in Cales. 187 and 187K are compared to determine which are controlling.

6.1.1.2 Governing Loads for Upper Bracing Members Cales. 187 and 187K each perform a single evaluation for the upper bracing members using enveloping loads from all upper bracing members. Section 7 of Cale. L-002547 determines that the original design basis evaluation in Cale. 187 (Ref. 3a) controls for the upper bracing members. The incorrect margin factor in Cale. 187 is referenced and review of the loads from Cales. 187 and 187K shows that the loads in Cale. 187K are governing and should have been used. For the enveloping evaluation of the upper bracing members, the loads in Cales. 187 and 187K are reviewed to determine which are controlling.

6.1.1.3 Governing Loads for Lower Bracing Gusset Plate Section Calculation L-002547 (Ref. 3c) evaluates normal stresses in the lower downcomer bracing gusset plate section using plastic section modulus. Review of the evaluation in Section 7.4 of

~_ef. 3c shows that it determined the loads considered in Section 2.8.2 of Cale. 187 (Ref. 3a) to CfUntrol by comparison of the governing margin factors in Calc.l 187 (Ref. 3a) and Cale. 187K (Ref. 3b). However, the governing evaluation in Section 6.3 of Cale. 187K (Ref. 3b) considered a reduction in moment based on actual member length while the governing evaluation in Section 2.8.2 of Cale. 187 (Ref. 3a) did not. Therefore, the margin factors cannot be compared to determine the controlling loads. For the lower bracing gusset plate section, the evaluations in Cales. 187 and 187K are reviewed to determine the controlling loads.

Analysis No. L-002547 Revision No. OA Page 18 6.1.2 Governing Load Combinations Sections 4.5 and 4.7 of Calculation 187 (Ref. 3a) evaluate the lower and upper bracing members for governing normal loading conditions (load combination 3) and governing abnormal loading conditions (load combination 7/7a), respectively, as defined in Table 4.3-2 of Ref. le. Review of Table 4.3-2 of Ref. le confirms that these load combinations govern for the normal and abnormal loading conditions.

Calculation 187K (Ref. 3b) addresses changes in LOCA chugging loads which are only induded in abnormal load combinations and, therefore, only evaluates for load combination 7/7a.

Calculation L-002547 (Ref. 3c) evaluates for the loading impact due to the 105% power uprate.

Per Ref. 3c, the 105% power uprate only affects accident suppression pool temperature and therefore the accident thermal load on the downcomer braces. Therefore, Ref. 3c does not address normal operating load conditions and only evaluates for load combination 7/7a.

As indicated in the Background section of Ref. 3c, an operating suppression pool temperature of 90°F was initially considered in the existing evaluations but the correct operating temperature is 105°F (see Section 1 of Ref. 3c). The impact of this increase in operating temperature is assessed in Calculation L-001799 (Ref. 3d), and the bracing members are qualified for normal operating conditions. Note that the evaluations in Calculation 187 (Ref. 3a) for normal operating conditions (load combination 3) conservatively use thermal loads due to the (at the time) accident temperature of 146°F.

Review of Sections 4.5 and 4. 7 of calculation 187 (Ref. 3a) shows that elastic section modulus was used to qualify the lower and upper braces for normal operating conditions (load combination 3). Since plastic section modulus was not used and the 105% power uprate only impacts accident temperature, the evaluations of the lower and upper bracing members for normal conditions (load combination 3) in Ref. 3a and Ref. 3d are still valid.

Therefore, the bracing members are only evaluated for the go.terning abnormal loading conditions (load combination 7/7a) in this calculation. Table 1 from Ref. 3c is provided for reference below in Table 6.1-1 which outlines the applicable combinations of LOCA and Safety/Relief Valve (SRV) loading along with the corresponding accident suppression pool temperature.

Analysis No. L-00254 7 Revision No. OA Page 19 Table 6.1-1: Refined LOCA Load Definition (Ref. 3c, Table 1)

Table 1: Refined LOCA Load Definition 1

1. LOCA Loading 2. SRV Loading Phenomen on Maximum Phenomen a Pool Temo Plant Case Condition2 Number Other3 Chugging All ADS Asym Single (Deg. F}

DBA-LOC A LI X X 150 L2 X X 150 L3 X 190 IBA-LOC A Ila X X 150 Ilb X x4 190 I2a X X 150 I2b X x4 190 SBA-LOC A Sl X 212 S2 X 212 S3 X xs xs 150 SBO SBOl X 212 SBO2 X 212 Table 1 Notes:

1) Other loads ( dead loads (D), live loads (L), safe shutdown earthquake (Ess), LOCA pressure loads (PA, Pa), etc.) are as identified in DAR Tables 4.1-1, 4.3-1, 4.3-2, 5.3-1, and 5.3-2 [Ref.

3].

2) For this table, DBA-LOC A is defined as a LOCA which will depressurize the reactor rapidly such that chugging, pool temperatu res> 150°F, and SRV loading cannot occur simultaneously, SBA-LOC A is defined as breaks which do not depressurize the reactor (i.e., the HPCS system can be used to maintain fluid inventory), and ffiA-LOC A is defined as all break sizes between these two extremes.

3) Other LOCA loading phenomen a include those loads early in the transient which occur at lower pool temperatures. These include downcomer water jet clearing, downcomer charging air bubble, pool swell, fall back, and ~ondensat ion Oscillation (CO). These loads all occur at pool temperatu res below 150°F, though not necessarily simultaneously.

4) SRV loading for Cases ~1 band I2b is reduced by a factor which is a function of RPV I pressure. By superimpo sing plant response for the various LOCA transients [see Section 6.4 of Ref. 7], the factor becomes a function of pool temperature. See Figure 1.

5) Apply either ADS or asymmetric SRV loads, but not both simultaneously.

Analysis No. L-002547 Revision No. 0A Page 20 6.1.2.1 Load Combinations for Lower Bracing Members and Gusset Plate Section Section 7 of Cale. L-002547 (Ref. 3c) considers two oombinations of loads for the lower down comer bracing which both fall under load oombination 7/7a. These two oombinations are outlined in Step 3 of the Evaluation Approach in Section 3 of Ref. 3c. These same two load combinations are considered in this evaluation, consistent with the latest existing analysis.

Load combinations 7-1 and 7-2 below were oonsidered in Cale. L-002547 (Ref. 3c), where:

s = Allowable stress D = Dead loads Ta = Accident temperature load LOCA = Loss of Coolant Accident loads SRV = Safety/Relief valve load Ess = Safe shutdown earthquake

1. Station Blackout cases (SBO) and Small Line Break LOCA cases 51 and 52:

This oombination bounds the SBO cases and Small Line Break LOCA cases 51 and 52 shown in Table 6.1-1. These cases do not experieice LOCA loading phenomena and occur with an accident pool temperature of 212°F.

2. LOCA line break cases L3, llb, and 12b:

7-2. S ~ D +Ta+ "f*SRV + LOCA + E 55 This oombination bounds the cases which have an accident pool temperature of 190°F (L3, Ilb, and 12b) as shown in Table 6.1-1. As outlined in Step 3b of the Methodology in Cale.

L-00254 7, 40% of the SRV loads are considered in combination with 100% of the LOCA loads. This reduction in SRV loading is based on Fig. 1 in Cale. L-002547, which relates the SRV load scale factor to suppression pool temperature when combined with LOCA chugging loads.

"YSRV.72 := 0.40 SRV reduction factor at 190°F Step 3b of the Methodology in Cale. L-002547 states that by engineering judgment the above load oombination (7-2) envelops all other LOCA line break cases (Ll, L2, Ila, 12a, and 53) because the increase in accident temperature to 150°F from 146°F (considered in Ref. 3a and Ref. 3b) is negligibly small . However, some of the existing lower downcomer bracing evaluatia,s for an accident temperature of 146°F considered plastic sections properties. Therefore, the existing evaluations at 146°F cannot be used to state that the braces are acceptable for the 150°F cases and an additional load oombination (7-3) is necessary to be checked.

Analysis No. L-002547 Revision No. OA Page 21

3. LOCA line break cases Ll, L2, Ila, 12a, and 53:

7-3. S ~ D +Ta+ 1*SRV + LOCA + E 55 This combination bounds the cases having an accident pool temperature of 150°F (L3, llb, and 12b) as shown in Table 6.1-1. Nctethat when considered with 1000/oofthe LOCAload there is no reduction in SRV loading at 150°F per Fig. 1 in Cale. L-002547, which relates the SRV load scale factor to suppression pool temperature when combined with LOCA chugging loads. However, per Ref. 3b, Section 6.0, page 1, Step 4 in the procedure states that SRV load may be reduced by 20% for resonant sequential symmetric discharge (RSSD) and by 30% for single valve subsequent actuation (SVSA) for load cases with lower temperatures (146°F; also applied for 150°F).

"1RSSD := 0.S0 SRV-RSSD reduction factor "1SVSA := 0.?0 SRV-SVSC>. reduction factor

Analysis No. L-002547 Revision No. OA Page 22 6.1.2.2 Load Combinations for Upper Bracing Members Section 7 .2 of Cale. L-00254 7 (Ref. 3c) evaluates the upper down comer braces using the total axial load and moments taken from Cale. 187 (Ref. 3a). As previously discussed, Cale. L-002547 inoorrectly identified that the enveloping loads from Cale. 187 oontrolled. Review of Cale. 187K (Ref. 3b) shows that the enveloping loads from that calculation control and LC #7 is considered to govern. The same combination is considered to govern in this evaluation. Since a single enveloping evaluation is performed for the upper downcomer braces, the 212°F thermal load is oonsidered with the full SRV and LOCA loads to bound all potential load oombinations.

S ~ D + Ta + SRV + LOCA + E55 + SNUB where s = Allowable stress D = Dead loads Ta = Accident temperature load LOCA = Loss of Coolant Accident loads (Chugging lateral and drag loads)

SRV = Safety/Relief valve load (reaction from downcomer pipe plus SRV support on upper brace)

Ess = Safe shutdown earthquake SNUB = Snubber support load Consistent with Cale. L-002547 (and Cale. 187K), only normal stress on the upper bracing members is evaluated. Review of Sections 2.10 and 4.7 of Cale. 187 shows that other stress checks have substantial margin.

Analysis No. L-002547 Revision No. OA Page 23 6.1.3 As-Built Conditions Section 3.4 of Cale. 187 (Ref. 3a) evaluates the lower downcomer bracing for nonconformity to erection tolerances and determines that the member eccentricities are acceptable by using the plastic section modulus. Subsequent evaluations of the lower bracing in Section 4 of Cale. 187, Cale. 187K (Ref. 3b), and Cale. L-002547 (Ref. 3c) do not account for the as-built eccentricities, which increase moment on the members.

The evaluation of the lower bracing members in this calculation accounts for the additional moment due to these eccentricities. Section 3.4 of Cale. 187 lists the as-built eccentricity for each lower bracing member, which have been reproduced in Design Input #5. As previously discussed, the existing analyses only modeled a single quadrant of the downcomer bracing system and considered it represents the whole system. The modeled brace members therefore represent multiple installed brace members. Section 3.4 of Cale. 187 lists the eccentricity for each actual brace member and the corresponding modeled member.

The evaluations performed in the existing calculations and this refined analysis are for the critical brace members in the single quadrant model. Therefore, for each critical member, the maximum eccentricity listed in Section 3.4 of Cale. 187 for the actual members represented by that modeled member is used to determine the additional moment. The additional moment is determined by multiplying the total axial load in the member by the maximum total eccentricity and is then added to total moment on the member.

Analysis No. L-002547 Revision No. OA Page 24

6. 1.4 Refinements in Evaluation 6.1.4.1 Refinement of Lower Bracing Member Analysis Refinement of the lower bracing members is required to account for as-built eccentricities and use correct bounding loads. To reduce conservatism in the evaluation of the lower bracing members, the following refinements are made:

• Determine directionality of moments to reduce total moments when load cases act in opposing directions. Currently, the resultant moments (vector sum of moments about the member primary axes) from each load are combined via absolute sum, instead of the moments about the primary axes for each load being added separately and then combined by vector sum.

• Use AISC Design Guide 19 (Ref. 4b) yield stress at elevated temperatures (discussed in Design Input #2)

• Use a 10% increase in yield stress to account for dynamic loading (discussed in Section 6.2) 6.1.4.2 Refinement of Upper Bracing Member Analysis Due to incorrect bounding loads being used in Cale. L-002547 (Ref. 3c), the upper bracing members must be re-evaluated using the correct bounding loads.

/ls previously discussed, enveloping loads for all upper bracing members are used to perform a single governing evaluation. The only refinements used in evaluation of the upper bracing members are as follows:

• Use AISC Design Guide 19 (Ref. 4b) yield stress at elevated temperatures (discussed in Design Input #2)

• Use a 10% increase in yield stress to account for dynamic loading (discussed in Section 6.2)

Analysis No. L-002547 Revision No. OA Page 25 6.2 ACCEPTANCE CRITERIA Consistent with Ref. 3a, Section 1.0 (and Ref. lb, Section 4.2.k and Table 7.2-4), structural steel members are designed using the elastic design provisions of the AISC 1969 "Specification for the Design, Fabrication & Erection of Structural Steel for Buildings," as presented in Ref. 4a, Part 5. However, for the lower downcomer braces and gusset plate section, Licensing Action LI-21-021 5 allows the use of plastic section properties.

As previously discussed, LC #7 controls for the bracing members based on the existing analyses and is considered in this evaluation. The allowable stresses for this LC (abnormal extreme environmental) are defined per Table 4.3-2 of the LaSalle DAR (Ref. le) and are provided below:

S7 = 1.6*AISC allowable not to exceed 0.95Fy Consistent with the existing evaluations, the maximum allowable stress of 0.95Fy is applicable to axial tension and bending, as well as axial compression. Section 1.7 of Cale. 187 (Ref. 3a) states that an allowable stress of 0.95Fy is acceptable for axial compression loads since the loads are dynamic in nature and last only a short time.

Additionally, per SRP Section 3.6.2 (Ref. Sb), Subsection III.2.a, a 10% increase of the minimum specified design yield strength may be used in the analysis to account for strain rate effects under dynamic loading. This increase is considered for the axial and bending allowables only.

Increased allowable bending stress of lower downcomer braces (Ref. 4a, Part 5, Section 1.5.1.4.5)

Fb.LB := I.I min[1.6(0.60Fy.A61 8),0.95*Fy .A6 l 8] = 52.25 -ksi Increased allowable axial stress of lower downcomer braces (Ref. 4a, Part 5, Section 1.5.1.1):

Fa.LB := I.I min[1.6(0.60*Fy.A6 l8), 0.95*Fy.A618] = 52.25-ksi Increased allowable bending stress of upper downcomer braces (Ref. 4a, Part 5, Section 1.5.1.4.5)

Fb.lJB := I.I min[1.6(0.60Fy.AS?2),0.95*Fy.AS?2] = 52.25-ksi Increased allowable axial stress of upper downcomer braces (Ref. 4a, Part 5, Section 1.5.1.1):

Fa.VB:= I.I min[1.6(0.60*Fy.AS72),0.95*Fy.A572] = 52.25-ksi Increased allowable bending/axial stress of gusset plate section (Ref. 4a, Part 5, Sections 1.5.1.1 and 1.5.1.4.5) :

Fba.gp := l.l-min[L6 (0.60*Fy.A SSS),0.95* Fy.ASSS] = 52.25 -ksi

Analysis No. L-002547 Revision No. OA Page 26 7.0 NUMERICALANALYSIS 7.1 LOWER DOWNCOMER BRACING, INNER RING For the 105% power uprate, the thermal load is increased based on the elevated Suppression Pool tempera ture. All other loads remain the same. Per Ref. 3a, Section 4.5 and Ref. 3c, Section 7 .3.2.1, the following members were previously qualified and are re-analyz ed herein:

• Member 126 / Node 94

• Member 75 / Node 49

• Member 86 / Node 63

• Member 7 / Node 11

• Member 57 / Node 49

• Member 47 / Node 35 7.1. 1 Member 126 I Node 94 7.1.1.1 Determine Current Design Loading Ref. 3a, Section 4.5 and Ref. 3b, Section 6.2.1 identify Member 126 as a critical lower bracing member for the Inner Ring bracing. Loads on the member are identified below.

The loads are taken as the maximum from Ref. 3a, Section 4.5, pages 4 & 8b or Ref. 3b, Section 6.2.1, page 4 unless noted otherwise.

Fa.DL := Okip MR.DL := 0.02ft-kip Axial load and moment due to dead load Fa.Th.14 6 := 53.1 !kip Axial load due to thermal load, 146°F (Ref.

3a, Section 4.5, page 4) 8134) "Node 112")

MB.Th.146 := ( -2866 ft- lbf ( "Node 94" Moment components due to thermal load, 146°F (Ref. 3e, PIPSYS Run 374PCG, 34789) "Node 112" ) Section D, page 1-11)

Mc.Th.14 6 := ( 78237 ft-lbf ( "Node 94" Fa.SVSA := 34.69kip Axial load due to SRV-SVSI\ (Ref. 3a, Section 4.5, page 3)

MB.SVSA := 5.800ft. kip Moment components for SRV-SVSI\ (Ref.

Mc.SVS A := 8.673ft-kip 3a, Section 4.12.1, page 14)

Analysis No. L-002547 Revision No. DA Page 27 Fa.RSSD := 39.76kip Axial load due to SRV-RSSD (Ref. 3a, Section 4.5, page 3)

MR.RSSD := 9.l5ft,kip Resultant moment for SRV-RSSD (Ref. 3a, Section 4.5, page 3)

Fa.LOCA := max(24.64 ,46.458)-k ip + l05.l9kip = 151.65-kip Axial load due to LOCA (Ref. 3a, Section 4.5, page 4; Ref. 3b, Section 6.2.1, page 4)

MB.LOCA.lat.db := 2.129ft, kip Moment components for LOCA chugging lateral load case, design basis (Ref. 3e, Mc.LOCA.lat.db := 5.292ft-kip PIPSYS Run 643PCG, Section D, page 1-11)

MB.LOCA .drag.db := l5.199ft-kip Moment components for LOCA chugging drag load case, design basis (Ref. 3e, Mc.LOCA.drag.db := 9.n&ft-kip PIPSYS Run A853YW, Section I, page 12-38)

MB.LOCA.lat.0808 := 2.130ft, kip Moment components for LOCA chugging lateral load case, NUREG-0808 (Ref. 3b, Mc.LOCA.lat.0808 := 25.689ft, kip Section 4.0, page 10)

The enveloping moment components for LOCA lateral+ drag are determined below.

MB.LOCA .- *- max{MB.LOCA.lat.db

• MB.LOCA.lat.0808) + M B.LOCA.drag.db MB.LOCA = 17.33-ft-kip M-

• • 'L.LOCA := max(M- **-'l_;,LOCA.lat.db

• M- + M-

.. -'\_;.LOCA.lat.0808) .. -'\_;.LOCA.drag.db Mc.LOCA = 35.42-ft-kip Fa.DRAG := Okip MR.DRAG := l.50ft* kip Axial load and moment due to bracing drag (SVSA or RSSD + Chugging ) (Ref. 3a, Section 4.5, page 4)

F a.Ess := Okip MR.Ess := 2.64ft*kip Axial load and moment due to seismic (Ref. 3a, Section 4.5, page 4)

Analysis No. L-002547 Revision No. OA Page 28 The thermal moment for the brace can be reduced by considering the actual length of the member since the PIPSYS analysis output is given at the working points of the analytical members (not the actual member ends) and the thermal moment gradient along the length of the member is known.

Figure 7 .1.1.1-1: Member 126 Location in PIPSYS Model (Ref. 3a, Section 2.1, page 2)

Figure 7 .1.1.1-2: Member 126 Location in Installed Configuration (Ref. 2a)

Analysis No. L-002547 Revision No. OA Page 29 The node-to-node length of this member is determined based on the measurements in Ref. 2a.

r2 := 19ft + 9in Radius to Pedestal wall and downcomer X- and Y-coordinates of the downcomers to which Member 126 attaches:

-r 1-sin(360deg- 346deg)) (-3.62) *- (r 1-cos(360deg- 346deg))- (14.51) xoc := ( = .ft Yoe.- - *ft

-r2*sin(360deg - 354deg) -2.06 r2* cos(360deg - 354deg) 19.64 Lnn := J(xoc2- xoc1)2 + (Yoc2 - Yoc 1)2 = S.36* ft Node-to-node length of Member 126 24in Lcrit := Lnn - - - = 4.36* ft Length to critical section of Member 126, 2 at outer face of downcomer Since the thermal moment gradient is known, pro-rate to find the thermal moment components at the face of the downcomer.

MB.Th.146 := lintCIJ)[( L:) *MB.Th.146 *Leri~ = 0.81-ft- kip Moment components due to thermal load at 146°F, linearly pro-rated to determine moment at face of downcomer Per Design Input #5, Member 126 was installed out of tolerance in the horizontal direction, thus additional moment needs to be added for the eccentricity.

elb.126i.h = o. 7sin Maximum horizontal eccentricity of a CBI brace number equivalent to Member 126 (previously specified)

Analysis No. L-002547 Revision No. OA Page 30 7.1.1.2 Evaluate Load Combination 7-1 Fa.Th.212 := IF212*Fa.Th.146 = 99 ,32-kip Axial load and moment components due to Ma.Th.212 := IF212*Ma.Th.14 6 = LS 2 *ft*kip thermal load, prorated for 212°F Mc.Th.212 := IF212*Mc.Th.14 6 = 131.14-ft-kip Design axial load on brace, SVSA and RSSD determined separately, Load Combination 7-1:

Fa.SVSA.71 := Fa.DL + Fa.Th.212 + Fa.SVSA +Fa.DRAG+ Fa.Ess = 134.0l-kip Fa.RSSD.71 := Fa.DL + Fa.Th.212 + Fa.RSSD +Fa.DRAG+ Fa.Ess = 139.08-kip Design moment on brace, SVSA, Load Combination 7-1:

MB.SVSA.71 := MB.Th.212 + MB.SVSA + elb.126i.h*Fa.SVSA.71 = lS.7-ft-kip Mc.SVSA.71 := Mc.Th.212 + Mc.SVSA = 139.81-ft*kip 2 2 MR.SVSA.71 := JMB.SVSA.71 + Mc.svsA.71 + MR.DL +MR.DRAG+ MR.Ess = 144 ft-kip Design moment on brace, RSSD, Load Combination 7-1:

MB.RSSD.71 := MB.Th.212 + e1b.126i.h*Fa.RSSD.71 = 10.2l*ft*kip Mc.RSSD.71 := Mc.Th.212 = 131.14-ft*kip 2 2 MR.RSSD.71 := JMB.RSSD.71 + Mc.RSSD.71 + MR.RSSD + MR.DL +MR.DRAG+ MR.Ess MR.RSSD.71 = 144.85-ft-kip As shown, RSSD controls.

Fa.RSSD.71 .

fa.126.ir.71 := A = 6.87-ksi Axial stress on brace, Load Combination 7-1 lb MR.RSSD.71 .

fb.126.ir.71 := Z = 34.88-ksi Bending stress on brace, Load Combination lb 7-1 fa.126.ir.71 fb.126.ir.71 O IC126.ir.LC71 := - - - - + - - - - = .80 Interaction coefficient for Member 126, Load Fa.LB Fb.LB Combination 7-1 1

MF126.ir.LC71 :=-IC_ _ _ _ = 1.25 Margin factor for Member 126, Load 126.ir.LC71 Combination 7-1

Analysis No. L-002547 Revision No. OA Page 31 7.1.1.3 Evaluate Load Combination 7-2 Fa.Th.190 := IF19o*Fa.Th.146 = 83.9l*kip Axial load and moment components due to Ma.Th.190 := IF19o*Ma.Th.146 = l.28*ft*kip thermal load, prorated for 190°F Mc.Th.190 := IF19o*Mc.Th.146 = 110.S*ft*kip SRV loads are reduced to 40% of the full load per Section 6.1.2.1. RSSD controls per the previous section.

Design axial load on brace, Load Combination 7-2:

Fa.tot.72 := Fa.DL + Fa.Th.190 + 'YSRV.72 Fa.RSSD + Fa.LOCA +Fa.DRAG+ Fa.Ess = 2Sl. 4?*kip Design moment on brace, Load Combination 7-2:

Ma.72 := MB.Th.190 + MB.LOCA + elb.126i.h*Fa.tot.72 = 34 -33 *ft*kip Mc.72 := Mc.Th.190 + Mc.LOCA = 146.22-ft-kip MR.tot.72 := MB.72 2 + Mc.72 2 + 'YSRV.72 MR.RSSD + MR.DL +MR.DRAG+ MR.Ess = lS8.0 2 *ft*kip Fa.tot.72 .

fa.126.ir.72 := A = 12.43-ksi Axial stress on brace, Load Combination 7-2 lb MR.tot.72 .

fb.126.ir.72 := Z = 38.05-ksi Bending stress on brace, Load Combination 7-2 lb fa.126.ir. 72 fb.126.ir. 72 IC126.ir.LC72 := - - - - + - - - - = 0.97 Interaction coefficient for Member 126, Load Fa.LB Fb.LB Combination 7-2 1

MF126.ir.LC72 := - - - - = 1.03 Margin factor for Member 126, Load IC126.ir.LC72 j Combination 7-2

Analysis No. L-002547 Revision No. OA Page 32 7.1.1.4 Evaluate Load Combination 7-3 Fa.Th.ISO:= IFiso*Fa.Th.146 = SS.9I*kip Axial load and moment components due to Ma.Th.ISO:= IF1so*Ma.Th.I4 6 = O.86*ft*kip thermal load, prorated for 150°F Mc.Th.ISO:= IFiso*Mc.Th.14 6 = 73.82-ft-kip SRV loads are reduced per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-3:

Fa.SVSA.150 := Fa.DL +Fa.Th.ISO+ "ISVSA Fa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = 23 L 84 *kip Fa.RSSD.lSO := Fa.DL +Fa.Th.ISO+ "IRSSDFa.RSSD + Fa.LOCA +Fa.DRAG+ Fa.Ess = 239 .3 6 *kip Design moment on brace, 150°F temperature case, with SRV-SVSA:

Ma.svsA.1so :=Ma.Th.ISO+ bsvsA Ma.svsA + Ma.LocA) *** = 36 .73-ft-kip

+ elb.126i.h. Fa.SVSA. l SO Mc.svsA.1so :=Mc.Th.ISO+ bsvsAMc.sv sA + Mc.LocA) = 11s.31.ft-kip 2 2 MR.SVSA.lSO := JMa.SVSA.lS 0 + Mc.SVSA.1S0 + MR.DL +MR.DRAG+ MR.Ess = l2S.l8*ft*kip Design moment on brace, 150°F temperature case, with SRV-RSSD:

MB.RSSD.lSO :=MB.Th.ISO+ MB.LOCA *** = 33.14-ft*kip

+ elb.126i.h. Fa.RSSD. lSO Mc.RSSD.ISO :=Mc.Th.ISO+ Mc.LOCA = 109.24-ft*kip J

MR.RSSD.lSO :=Ma.RSSD.l I SO2 + Mc.RSSD.lSO2 + "IRSSDMR.RSSD ... = l2S. 63*ft*k P

+ MR.DL + MR.DRAG+ MR.Ess

Analysis No. L-002547 Revision No. OA Page 33 As shown, RSSD controls.

Fa.RSSD.150 fa.126.ir. 73 := A = 11.83

• ksi Axial stress on brace, Load Combination 7-3 lb MR.RSSD.150 fb.126.ir.73 := Z = 30.26-ksi Bending stress on brace, Load lb Combination 7-3 fa.126.ir. 73 fb.126.ir. 73 IC126.ir.LC73 := - - - - + - - - - = 0.81 Interaction coefficient for Member 126, Load Fa.LB Fb.LB Combination 7-3 1

MF 126.ir.LC73 := - - - - - = 1.24 Margin factor for Member 126, Load IC126.ir.LC73 Combination 7-3

Analysis No. L-002547 Revision No. OA Page 34

7. 1.2 Member 75 I Node 49 7.1.2.1 Determine Current Design Loading Ref. 3a, Section 4.5 and Ref. 3b, Section 6.2.1 identify Member 75 as a critical lower bracing member for the Inner Ring bracing. Loads on the member are identified below.

Fa.DL := 0kip MR.DL := 0.078ft*kip Axial load and moment due to dead load (Ref. 3a, Section 4.5, page 4)

Fa.Th.146 := 20.92kip Axial load due to thermal load, 146°F

-9806) "Node 88")

MB.Th.146 := ( -10966 ft- lbf ( "Node49" Moment components due to thermal load, 146°F (Ref. 3e, PIPSYS Run 374PCG, 17956) "Node 88") Section D, page 1-8)

( 64093 ft,lbf

=

Mc. Th.146 ( "Node49" Per Ref. 3a, Section 4.5, page 3, SVSA controls over RSSD.

Fa.SVSA := 48.08kip Axial load due to SRV-SVSA (Ref. 3a, Section 4.5, page 4)

MB.SVSA := 8.515ft-kip Moment components for SRV-SVSA load case (Ref. 3a, Section 4.12.1, page 14)

Mc.SVSA := 18.847ft-kip Fa.LOCA := max(45.61,48.9 22)*kip + 115.60kip = 164.52-kip Axial load due to LOCA (Ref. 3a, Section 4.5, page 4; Ref. 3b, Section 6.2.1, page 4)

MB.LOCA.lat.db := 0.505ft*kip Moment components for LOCA chugging lateral load case, design basis (Ref. 3e, Mc.LOCA.lat.db := 12.037ft-kip PIPSYS Run ID 643PCG, Section D, page 1-8)

MR.LOCA.lat.0808 := 22.755ft*kip Resultant moment for LOCA chugging lateral load case, NUREG-0808 (Ref. 3b, Section 6.2.1, page 4)

IMB.LOCA.drag.db := 21.579ft, kip Mbment components for LOCA chugging drag load case, design basis (Ref. 3e, Mc.LOCA.drag.db := 14.326ft-kip PIPSYS Run A853YW, Section I, page 12-35)

By observation, the NUREG-0808 lateral chugging loads control.

Analysis No. L-002547 Revision No. OA Page 35 Fa.DRAG := Okip MR.DRAG:= l.50ft-kip Axial load and moment due to bracing drag (SVSA or RSSD + Chugging) (Ref. 3a, Section 4.5, page 4)

Fa.Ess := Okip MR.Ess := 3.55ft*kip Axial load and moment due to seismic (Ref. 3a, Section 4.5, page 4)

The thermal moment for the brace can be reduced by considering the actual length of the member since the PIPSYS analysis output is given at the working points of the analytical members (not the actual member ends) and the thermal moment gradient along the length of the member is known.

Figure 7.1.2.1-1: Member 75 Location in PIPSYS Model (Ref. 3a, Section 2.1, page 2)

Figure 7 .1.2.1-2: Member 75 Location in Installed Configuration (Ref. 2a)

Analysis No. L-002547 Revision No. OA Page 36 The node-to-node length of this member is determined based on the measurements in Ref. 2a.

r2 := 19ft + 9in Radii to working points X- and Y-coordinates of the working points to which Member 75 attaches:

• -(r 1-cos(90deg-1 8deg)J-(4.62 ) *-(rrsin(90d eg-18deg)J- (14.23) xoc .- - .ft Yoe*- - *ft r2*cos(90deg - 30deg) 9.87 r2*sin(90deg- 30deg) 17.l Lnn := J(xoc2- xoc1)2 + (Yoc2 - Yoc 1) =

2 5.99* ft Node-to-node length of Member 75 24in Lcrit := Lnn - - - = 4.99* ft Length to critical section of Member 75, 2 at outer face of downcomer Since the thermal moment gradient is known, pro-rate to find the thermal moment components at the face of the down comer.

Me.To.146 := linterp[( L:}Me.Th.146*Lc,i~ = 10.77-ft*kip Moment components due to thermal load at 146°F, linearly pro-rated to determine moment at Mc.Th.146 := linterp[( L:}Mc.Th.146*Lcri~ = 56.39-ft*kip face of downcomer Per Design Input #5, Member 75 was installed out of tolerance in the horizontal direction, thus additional moment needs to be added for the eccentricity.

elb. 7 S.h = 0.70 in Maximum eccentricity of a CBI brace number equivalent to Member 75 (previously specified)

Analysis No. L-002547 Revision No. OA Page 37 7.1.2.2 Evaluate Load Combination 7-1 Fa.Th.212 := IF212*Fa.Th.146 = J9.12-kip Axial load and moment components due to MB.Th.212 := IF212*MB.Th.146 = 20.14-ft-kip thermal load, prorated for 212°F Mc.Th.212 := IF212*Mc.Th.146 = 105.45-ft-kip Design axial load on brace, Load Combination 7-1 :

Fa.tot.71 := Fa.DL + Fa.Th.212 + Fa.SVSA +Fa.DRAG+ Fa.Ess = 87 -2 *kip Design moment on brace, Load Combination 7-1:

MB.71 := MB.Th.212 + MB.SVSA + elb.75.h*Fa.tot.71 = JJ.75-ft-kip Mc.71 := Mc.Th.212 + Mc.SVSA = 124.3-ft-kip MR.tot.71 := MB.71 2 + Mc.71 2 + MR.DL +MR.DRAG+ MR.Ess = 133.92 -ft-kip Fa.tot.71 .

fa.75.ir.71 := A = 4.31-ksi Axial stress on brace, Load Combination 7-1 lb MR.tot.71 .

fb.75.ir.71 := z = 32.25-ksi Bending stress on brace, Load Combination 7-1 lb fa.75.ir.71 fb.75.ir.71 IC75.ir.LC71 := - - - + - - - = 0.70 Interaction coefficient for Member 75, Load Fa.LB Fb.LB Combination 7-1 I

MF75.ir.LC71 := IC = 1.43 Margin factor for Member 75, Load 75.ir.LC71 Combination 7-1

Analysis No. L-002547 Revision No. OA Page 38 7.1.2.3 Evaluate Load Combination 7-2 Fa.Th.190 := IF19o*Fa.Th.146 = 33.05 -kip Axial load and moment components due to Ma.Th.190 := IF19o*Ma.Th.14 6 = 17.0l*ft-kip thermal load, prorated for 190°F Mc.To.190 := IF19o*Mc.To.14 6 = 89.l*ft*kip SRV loads are reduced to 40% of the full load per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-2:

Fa.tot.72 := Fa.DL + Fa.Th.190 + "YSRV.72Fa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = 2 I6.8l*kip Design moment on brace, Load Combination 7-2:

MB.72 := MB.Th.190 +"'fsRV.72MB.SVSA + MB.LOCA.drag.db + elb.75.h*Fa.tot.72 = 54.65-ft*kip Mc.72 := Mc.Th.190 + "YSRV.72Mc.svsA + Mc.LOCA.drag.db = 110.96-ft-kip MR.tot.72 := MB.72 2 + Mc.722 + MR.LOCA.lat.0808 + MR.DL + MR.DRAG+ MR.Ess = lSl.S?*ft*kip Fa.tot.72 .

fa.75.ir.72 := A = 10.72-ksi Axial stress on brace, Load Combination 7-2 lb MR.tot.72 .

fb.75.ir.72 := Z = 36.S*kst Bending stress on brace, Load Combination 7-2 lb fa.75.ir.72 fb.75.ir.72 IC7s.ir.LC72 := + - - - = 0.90 Interaction coefficient for Member 75, Load Fa.LB Fb.LB Combination 7-2 1

MF75.ir.LC72 := - - - - = 1.11 Margin factor for Member 75, Load IC75.ir.LC72 Combination 7-2

Analysis No. L-002547 Revision No. OA Page 39 7.1.2.4 Evaluate Load Combination 7-3 Fa.Th.ISO:= IFiso*Fa.Th.I46 = 22 ,02-kip Axial load and moment components due to Ma.Th.ISO:= IFiso*Ma.Th.I4 6 = I 1.34-ft-kip thermal load, prorated for 150°F Mc.Th.ISO:= IFiso*Mc.Th.14 6 = S9.36-ft-kip SRV loads are reduced per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-3:

Fa.SVSA.150 := Fa.DL +Fa.Th.ISO+ "ISVSA Fa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = 220.2-kip Design moment on brace, 150°F temperature case, with SRV-SVSA:

MB.SVSA.ISO :=MB.Th.ISO+ '"YSVSA MB.SVSA + MB.LOCA.drag.db ... = Sl.?2*ft*kip

+ elb.7s.h*Fa.SVSA.ISO l

Mc.SVSA.ISO :=Mc.Th.ISO+ '"YSVSA Mc.SVSA + Mc.LOCA.drag.db = 86.88-ft-kip MR.SVSA.lSO := MB.SVSA.1S02 + Mc.SVSA.IS02 + [MR.DL ... = I 28 -99 *ft-kip

+MR.DRAG ...

+MR.Ess ...

+ MR.LOCA.lat.0808 Fa.SVSA. I SO .

fa.7S.ir.73 := A = 10.88-ksi Axial stress on brace, Load Combination 7-3 lb MR.SVSA. I SO .

fb.7S.ir.73 := Z = 31.06-ksi Bending stress on brace, Load Combination lb 7-3 fa.7S.ir.73 fb.7S.ir.73 IC7s.ir.LC73 := - - - + - - - = 0.80 Interaction coefficient for Member 75, Load Fa.LB Fb.LB Combination 7-3 I

MF7S.ir.LC73 := - - - - = l.2S Margin factor for Member 75, Load IC7s.ir.LC73 Combination 7-3

Analysis No. L-002547 Revision No. 0A Page 40 7.1.3 Member 861 Node 63 7.1.3.1 Determine Current Design Loading Ref. 3a, Section 4.5 and Ref. 3b, Section 6.2.1 identify Member 86 as the critical lower bracing member for the Inner Ring bracing. Loads on the member are identified below.

Fa.DL := Okip MR.DL := 0.015ft*kip Axial load and moment due to dead load (Ref. 3a, Section 4.5, page 4)

Fa.Th.146 := 22kip Axial load due to thermal load, 146°F (Ref.

3a, Section 4.5, page 4) 2668)

Ma.Th.146 := ( 1813 ft-lbf "Node 88")

( "Node 63" Moment components due to thermal load, 146°F (Ref. 3e, PIPSYS Run 374PCG, Mc.Th.146

= 4559)

( 88671 ft-lbf

Node 88")

( "Node 63" Section D, page 1-8)

Per Ref. 3a, Section 4.5, page 3, svg,. controls over RSSD.

Fa.SVSA := 22.412kip Axial load due to SRV-svg,.

Moment components for SRv-svg,. load case, design basis (Ref. 3e, PIPSYS Run ID 595YW, Section I, page 4-25 and PIPSYS Run ID 596YW, Section I, page 5-24):

MB.SVSA := (1.757 + 3.352)ft-kip = 5.11-ft-kip Mc.SVSA := (3.632 + 18.206)ft-kip = 21.84-ft*kip Fa.LOCA := max.(4.40, 60.481)-kip + 38.85kip = 99.33-kip Axial load due to LOCA (Ref. 3a, Section 4.5, page 4; Ref. 3b, Section 6.2.1, page 4)

MB.LOCA.lat.db := l.12ft*kip Moment components for LOCA chugging lateral load case, design basis (Ref. 3e, Mc.LOCA.lat.d b := 4.098ft-kip PIPSYS Run ID 643PCG, Section D, page 1-8)

Ma.LOCA.lat.0 808 := l.621ft-kip Moment components for LOCA chugging lateral load case, NUREG-0808 (Ref. 3b, Mc.LOCA.lat.0 808 := 30.3?2ft-kip Section 4.0, page 4)

MR.LOCA.drag.db := 29.07ft-kip Resultant moment for LOCA chugging drag load case, design basis (Ref. 3b, Section 6.2.1, page 4)

By observation, the NUREG-0808 lateral chugging loads control.

Analysis No. L-002547 Revision No. OA Page 41 Fa.DRAG := Okip MR.DRAG := 1.11 ft. kip Axial load and moment due to bracing drag (SVSA or RSSD + Chugging) (Ref. 3a, Section 4.5, page 4)

Fa.Ess := Okip MR.Ess := 3.02ft-kip Axial load and moment due to seismic (Ref. 3a, Section 4.5, page 4)

The thermal moment for the brace c.an be reduced by considering the actual length of the member since the PIPSYS analysis output is given at the working points of the analytic.al members (not the actual member ends) and the thermal moment gradient along the length of the member is known.

Figure 7.1.3.1-1: Member 86 Location in PIPSYS Model (Ref. 3a, Section 2.1, page 2)

/_

-~I..*

Figure 7 .1.3.1-2: Member 86 Loc.ation in Installed Configuration (Ref. 2a)

Analysis No. L-002547 Revision No. OA Page 42 The node-to-node length of this member is determined based on the measurements in Ref. 2a.

r 2 := 19ft + 9in Radii to working points Node-to-node length of Member 86 24in Lcrit := Lnn - - - = 3.79-ft Length to critical section of Member 86, 2 at outer face of downcomer Since the thermal moment gradient is known, pro-rate to find the thermal moment components at the face of the down comer.

Me.Th.146 := linterp[( L:}Me.To.14 6*Lcri~ = '-99 -ft-kip Moment components due to thermal load at 146°F, linearly pro-rated to determine moment at face of downcomer Per Design Input #5, Member 86 was installed out of tolerance in the horizontal direction, thus additional moment needs to be added for the eccentricity.

elb.86.h = 0.70 in Maximum eccentricity of a CBI brace number equivalent to Member 86 (previously specified)

Analysis No. L-002547 Revision No. OA Page 43 7.1.3.2 Evaluate Load Combination 7-1 Fa.Th.212 := IF212*Fa.Th.146 = 4 1.1 4 *kip Axial load and moment due to thermal load, MB.Th.212 := IF212*Ma.Th.14 6 = 3.72-ft-kip prorated for 212°F Mc.Th.212 := IF212*Mc.Th.14 6 = 132.99-ft-kip Design axial load on brace, Load Combination 7-1:

Fa.tot.71 := Fa.DL + Fa.Th.212 + Fa.SVSA +Fa.DRAG+ Fa.Ess = 63 kip Design moment on brace, Load Combination 7-1:

MB.71 := MB.Th.212 + MB.SVSA + elb.86.h'Fa.tot.71 = 12 ft-kip Mc.71 := Mc.Th.212 + Mc.SVSA = 154.83-ft-kip Fa.tot.71 .

fa.86.ir.71 := A = 3.14-kst Axial stress on brace, Load Combination 7-1 lb MR.tot.71 fb.86.ir.71 := Z = 38.41-ksi Bending stress on brace, Load Combination 7-1 lb fa.86.ir.71 fb.86.ir.71 IC86.ir.LC71 := - - - + - - - = 0.80 Interaction coefficient for Member 86, Load Fa.LB Fb.LB Combination 7-1 1

MFs6.ir.LC71 := IC = 1. 26 Margin factor for Member 86, Load 86.ir.LC71 Combination 7-1

Analysis No. L-002547 Revision No. OA Page 44 7.1.3.3 Evaluate Load Combination 7-2 Fa.Th.190 := IF19o*Fa.Th.146 = 34.76 -kip Axial load and moment due to thermal load, prorated for 190°F Ms.Th.190 := IF19o*Ms.Th.l46 = 3.15 *ft*kip Mc.Th.190 := IF19o*Mc.Th.l46 = 112.37-ft*kip SRV loads are reduced to 40% of the full load per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-2:

Fa.tot.72 := Fa.DL + Fa.Th.190 + "fSRV.72Fa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = 143 ,06-kip Design moment on brace, Load Combination 7-2:

MB.72 := MB.Th.190 + "fSRV.72'MB.SVSA + MB.LOCA.lat.0808 + elb.86.h*Fa.tot.72 = 15.l6*ft*kip Mc.72 := Mc.Th.190 + "fsRv.12*M c.svsA + Mc.LOCA.lat.0808 = 151.47,ft-kip MR.tot.72 := MB.72 2 + Mc.722 + (MR.DL ... J = ISS.44*ft*kip

+ MR.DRAG+ MR.Ess ...

+ MR.LOCA.drag.db Fa.tot.72 .

fa.86.ir.72 := A = 7.07-ksi Axial stress on brace, Load Combination 7-2 lb MR.tot.72 .

fb.86.ir.72 := Z = 44.66,kst Bending stress on brace, Load Combination 7-2 lb fa.86.ir.72 fb.86.ir.72 ICs6.ir.LC72 := - - - + - - - = 0.99 Interaction coefficient for Member 86, Load Fa.LB Fb.LB Combination 7-2 I

MFs6.ir.LC72 := - - - - = 1.01 Margin factor for Member 86, Load IC86.ir.LC72 Combination 7-2

Analysis No. L-002547 Revision No. OA Page 45 7.1.3.4 Evaluate Load Combination 7-3 Fa.Th.ISO:= IFiso*Fa.Th.146 = 2J.I6-kip Axial load and moment due to thermal load, prorated for 150°F MB.Th.ISO:= IFiso*MB.Th.I46 = 2.I*ft-kip Mc.Th.ISO:= IFiso*Mc.Th.I46 = 74.86-ft-kip SRV loads are reduced per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-3:

Fa.SVSA.ISO := Fa.DL +Fa.Th.ISO+ '"YSVSA Fa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = l3B.IB*kip Design moment on brace, 150°F temperature case, with SRV-SVSA:

MB.ISO:= MB.Th.ISO+ '"YSVSA"MB.SVSA + MB.LOCA.lat.0808 + elb.86.h*Fa.SVSA.ISO = IS.3S*ft*kip Mc.ISO:= Mc.Th.ISO+ '"YSVSA'Mc.svsA + Mc.LOCA.Iat.0808 = l20.5 2 *ft*kip MR.tot.ISO:= MB.IS0 2 + Mc.IS0 2 + (MR.DL *** J = IS4.7I*ft*kip

+MR.DRAG+ MR.Ess ***

+ MR.LOCA.drag.db Fa.SVSA. I SO .

fa.86.ir.73 := A = 6.83-ksi Axial stress on brace, Load Combination 7-3 lb MR.SVSA. I SO .

fb.86.ir.73 := Z = 31.06-kst Bending stress on brace, Load Combination lb 7-3 fa.86.ir.73 fb.86.ir.73 ICs6.ir.LC73 := + - - - = 0.73 Interaction coefficient for Member 86, Load Fa.LB Fb.LB Combination 7-3 MF86.ir.LC73 := = 1.38 Margin factor for Member 86, Load\

IC86.ir.LC 3 Combination 7-3

Analysis No. L-002547 Revision No. OA Page 46

7. 1.4 Member 7 I Node 11 7.1.4.1 Determine Current Design Loading Ref. 3a, Section 4.5 and Ref. 3b, Section 6.2.1 identify Member 7 as a critical lower bracing member for the Inner Ring bracing. Loads on the member are identified below.

Fa.DL := 0kip MR.DL := 0.0lSft*kip Axial load and moment due to dead load (Ref. 3a, Section 4.5, page 4)

Fa.Th.146 := 7.57kip MR.Th.146 := 2.79ft-kip Axial load and moment due to thermal load, 146°F (Ref. 3a, Section 4.5, page 4)

Per Ref. 3a, Section 4.5, page 3, SVSA controls over RSSD.

Fa.SVSA := 16.97kip MR.SVSA := 27.53ft-kip Axial load and moment due to SRV-SV~

(Ref. 3a, Section 4.5, page 3)

Fa.LOCA := max(14.58 ,27.732)-kip + 12.22kip = 39.95-kip Axial load due to LOCA (Ref. 3a, Section 4.5, page 4; Ref. 3b, Section 6.2.1, page 3)

Moment load due to LOCA (Ref. 3a, Section 4.5, page 4; Ref. 3b, Section 6.2.1, page 3)

MR.LOCA := max:(22.52, 11.21 I) ft-kip+ 38.44ft-kip = 60.96*ft*kip Fa.DRAG := 0kip MR.DRAG := 0.29ft, kip Axial load and moment due to bracing drag (SVSA or RSSD + Chugging) (Ref. 3a, Section 4.5, page 4)

Fa.Ess := 0kip MR.Ess := 3.02ft*kip Axial load and moment due to seismic (Ref. 3a, Section 4.5, page 4)

Per Design Input #5, Member 7 was installed out of tolerance, thus additional moment needs to be added for the eccentricity.

elb.7 = 0.06 in Maximum eccentricity of a CBI brace number equivalent to Member 7 (previously specified)

Analysis No. L-002547 Revision No. OA Page 47 7.1.4.2 Evaluate Load Combination 7-1 Fa.Th.212 := IF212*Fa.Th.146 = l4.16-kip Axial load and moment due to thermal load, MR.Th.212 := IF212-MR.Th.146 = 5.22-ft-kip prorated for 212°F Design axial load on brace, Load Combination 7-1:

Fa.tot.71 := Fa.DL + Fa.Th.212 + Fa.SVSA +Fa.DRAG + Fa.Ess = Jl.IJ-kip Design moment on brace, Load Combination 7-1:

MR.tot. 71 := MR.DL + MR.Th.212 + MR.SVSA + MR.DRAG+ MR.Ess = 36.07 *ft.kip F

f * *=

a.7.rr.71

• a.tot.?l A

= 1.54-ksi Axial stress on brace, Load Combination 7-1 lb MR.tot.71 + Fa.tot.11*e1b.7 .

f,b.7.ir.71  := z = 8.72-kst Bending stress on brace, Load Combination 7-1 lb fa.7.ir.71 fb.7.ir.71 IC7.ir.LC71 := F + = 0.20 Interaction coefficient for Member 7, Load a.LB Fb.LB Combination 7-1 1

MF7.ir.LC71 :=-IC_ _ _ = 5.09 Margin factor for Member 7, Load 7.ir.LC71 Combination 7-1

Analysis No. L-002547 Revision No. OA Page 48 7.1.4.3 Evaluate Load Combination 7-2 Fa.Th.190 := IF19o*Fa.Th.146 = 11.96-kip Axial load and moment due to thermal load, MR.Th.190 := IF19o*MR.Th.146 = 4.41-ft-kip prorated for 190°F SRV loads are reduced to 40% of the full load per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-2:

Fa.tot.72 := Fa.DL + Fa.Th.190 + "YSRV.72Fa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = SS.7*kip Design moment on brace, Load Combination 7-2:

MR.tot.72 := MR.DL + MR.Th.190 + "YSRV.72MR.SVSA + MR.LOCA +MR.DRAG+ MR.Ess = 79 -7l*ft*kip Fa.tot.72 .

fa.7.ir.72 := Alb = 2.9-ksi Axial stress on brace, Load Combination 7-2 r MR.tot.72 + Fa.tot.72'elb.7 k .

1 b.7.ir.72 := z = 19.27* SI Bending stress on brace, Load Combination 7-2 lb fa.7.ir.72 fb.7.ir.72 O IC7.ir.LC72 := - - - + - - - = .42 Interaction coefficient for Member 7, Load Fa.LB Fb.LB Combination 7-2 I

MF7.ir.LC72 := - - - - = 2.36 Margin factor for Member 7, Load IC7.ir.LC72 Combination 7-2

Analysis No. L-00254 7 Revision No. OA Page 49 7.1.4.4 Evaluate Load Combination 7-3 Fa.Th.ISO:= IFiso*Fa.Th.I46 = ?.97-kip Axial load and moment due to thermal load, prorated for 150°F MR.Th.ISO:= IFiso*MR.Th.I46 = 2.94*ft*kip SRV loads are reduced per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-3:

Fa.SVSA.ISO := Fa.DL +Fa.Th.IS O+ 1SVSA Fa.SVSA + Fa.LOCA +Fa.DRA G+ Fa.Ess = s9.S-kip Design moment on brace, 150°F temperatu re c.ase, with SRV-SVSA:

MR.SVSA .ISO := MR.DL +MR.Th.ISO+ 1SVSA MR.SVSA + MR.LOCA +MR.DRAG+ MR.Ess = 86.49-ft*ki p

Fa.SVSA.ISO .

fa.7.ir.73 := A = 2.96-ksi Axial stress on brace, Load Combination 7-3 lb r *- MR.SVSA.ISO + Fa.SVSA.ISo*etb.7 O k .

lb.7.ir.73 .- Ztb =2 9 SI

.. Bending stress on brace, Load Combination 7-3 fa.7.ir.73 fb .7.ir.73 IC7.ir.LC73 := - - - + - - - = 0 .46 Interaction coefficient for Member 7, Load Fa.LB Fb.LB Combination 7-3 I

MF7.ir.LC73 := IC = 2.19 Margin factor for Member 7, Load 7.ir.LC73 Combination 7-3

Analysis No. L-002547 Revision No. 0A Page 50

7. 1.5 Member 57 I Node 49 7.1.5.1 Determine Current Design Loading Ref. 3a, Section 4.5 and Ref. 3b, Section 6.2.1 identify Member 57 as a critical lower bracing member for the Inner Ring bracing. Loads on the member are identified below.

Fa.DL := 0kip MR.DL := 0.097ft, kip Axial load and moment due to dead load (Ref. 3a, Section 4.5, page 4)

Fa.Th.146 := 32.4lkip Axial load due to thermal load, 146°F (Ref.

3a, Section 4.5, page 4)

-370) "Node42")

Ma.Th.146 := ( 2030 ft-lbf ( "Node49" Moment components due to thermal load, 146°F (Ref. 3e, PIPSYS Run 374PCG, 965) Node 42") Section D, page 1-6)

Mc.Th.146 := ( 7482 ft-lbf ( "Node49" Fa.SVSA := 43.06kip Axial load due to SRV-SVSA (Ref. 3a, Section 4.5, page 3)

Moment components for SRV-SVSA load case, design basis (Ref. 3e, PIPSYS Run ID 595YW, Section I, page 4-23 and PIPSYS Run ID 596YW, Section I, page 5-22):

MB.SVSA := (1.137 + 0.749)ft*kip = 1.89-ft*kip Mc.SVSA := (12.039 + l.715)ft*ki p = 13.75*ft*kip Fa.RSSD := 46.03kip Axial load and moment due to SRV-RSSD (Ref. 3a, Section 4.5, page 3)

MR.RSSD := 9.28ft,kip Fa.LOCA := max(41.58 , 10.710)-kip + 135.16kip = 176.74-kip Axial load due to LOCA (Ref. 3a, Section 4.5, page 4; Ref. 3b, Section 6.2.1, page 3)

Ma.LOCA.lat.db := 0.678ft-kip Moment components for LOCA chugging lateral load case, design basis (Ref. 3e, Mc.LOCA.lat.db := l3.Sft*kip PIPSYS Run ID 643PCG, Section D, page 1-6)

MR.LOCA.lat.0808 := 12.093ft*kip Resultant moment for LOCA chugging lateral load case, NUREG-0808 (Ref. 3b, Section 6.2.1, page 3)

The design basis LOCA chugging lateral moment controls by observation.

MB.LOCA.drag.db := 4.7llft*kip Moment components for LOCA chugging drag load case, design basis (Ref. 3e, Mc.LOCA .drag.db := l 8.8 l 7ft* kip PIPSYS Run A853YW, Section I, page 12-34)

Analysis No. L-002547 Revision No. OA Page 51 Fa.DRAG := Okip MR.DRAG := l.86ft*kip Axial load and moment due to bracing drag (SVSA or RSSD + Chugging ) (Ref. 3a, Section 4.5, page 4)

Fa.Ess := Okip MR.Ess := 3.28ft-kip Axial load and moment due to seismic (Ref. 3a, Section 4.5, page 4)

The thermal moment for the brace can be reduced by considering the actual length of the member since the PIPSYS analysis output is given at the worl<ing points of the analytic.al members (not the actual member ends) and the thermal moment gradient along the length of the member is known.

Figure 7.1.5.1-1 : Member 57 Location in PIPSYS Model (Ref. 3a, Section 2.1, page 2)

L - * --*~

Figure 7 .1.5.1-2: Member 57 Location in Installed Configuration (Ref. 2a)

Analysis No. L-002547 Revision No. OA Page 52 The node-to-node length of this member is determined based on the measurements in Ref. 2a.

r1 := 19ft + 9in Radii to downcomers X- and Y-coordinates of the downcomers to which Member 57 attaches:

xoc *= (

r1-cos(90deg - 30deg) J= (9.87 ) .ft Yoe:=

r1*sin(90deg - 30deg) J ( 17.1 )

=

r2*cos(90deg - 42deg) ( r2* sin(90deg - 42deg) *ft 15.56 17.28 Lnn := J(xoc2 - xoc1)2 + (Yoc2 - Yoc 1) 2

= 5.68* ft Node-to-node length of Member 57 24in Lcrit := Lnn - - - = 4.68* ft Length to critical section of Member 57, 2 at outer face of downcomer Since the thermal moment gradient is known, pro-rate to find the thermal moment components at the face of the downcomer.

MB.Th.146 := linterp[( L:) ,MB.Th.146*Lcri~ = 1.61-ft*kip Moment components due to thermal load at 146°F, linearly pro-rated to determine moment at Mc.Th. I 46 := face of downcomer linterp[( L:). Mc.Th.146 , Leri~ = 6 -34 *ft. kip MR.Th.146 := MB.Th.14l + Mc.Th.14/ = 654 -ft*kip Resultant thermal moment at 146°F Per Design Input #5, Member 57 was installed out of tolerance in the horizontal direction, thus additional moment needs to be added for the eccentricity.

elb.57.h = 3*2 in Maximum eccentricity of a CBI brace number equivalent to Member 57 (previously specified)

Analysis No. L-002547 Revision No. OA Page 53 7.1.5.2 Evaluate Load Combination 7-1 Fa.Th.212 := IF212*Fa.Th.146 = 60.61-kip Axial load and moment due to thermal load, MR.Th.212 := IF212*MR.Th.146 = 12.22*ft*kip prorated for 212°F Design axial load on brace, Load Combination 7-1:

Fa.SVSA.71 := Fa.DL + Fa.Th.212 + Fa.SVSA +Fa.DRAG+ Fa.Ess = 103.67-kip Fa.RSSD.71 := Fa.DL + Fa.Th.212 + Fa.RSSD +Fa.DRAG+ Fa.Ess = 106.64-kip Design moment on brace, Load Combination 7-1:

MR.SVSA.71 := MR.DL + MR.Th.212 + MB.SVSA 2 + Mc.SVSA 2 +MR.DRAG+ MR.Ess = 3 1.34* ft*kip MR.RSSD.71 := MR.DL + MR.Th.212 + MR.RSSD +MR.DRAG+ MR.Ess = 26.74-ft*kip Fa.SVSA.71 fa.57.ir.SVSA.71 := A = 5.12-ksi Axial stress on brace, Load Combination lb 7-1, with SRV-SVSG.

MR.SVSA.71 + Fa.SVSA.71 'elb.57.h k .

f,b.57.ir.SVSA.71 :=

z = 14.21

• SI Bending stress on brace, lb Load Combination 7-1, with SRV-SVSG.

fa.57 .ir.SVSA. 71 fb.57 .ir.SVSA. 71 1Cs7.ir.SVSA.LC71 := Fa.LB + Fb.LB Interaction coefficient for

= 0.37 Member 57, Load Combination 7-1, with SRV-SVSG.

Fa.RSSD.71 fa.57.ir.RSSD.71 := A = 5.27-ksi Axial stress on brace, Load Combination lb 7-1, with SRV-RSSD MR.RSSD.71 + Fa.RSSD.71'elb.57.h .

f,b.57.ir.RSSD.71 := z Bending stress on brace,

= 13.29-ksi lb Load Combination 7-1, with SRV-RSSD fa.57.ir.RSSD.71 fbl.57.ir.RSSD.71 IC57.ir.RSSD.LC71 := - - - - - + - - - - - = 0.36 Interaction coefficient for Fa.LB Fb.LB Member 57, Load Combination 7-1, with SRV-RSSD ICs7.ir.LC71 := max(IC57_ir.SVSA.LC71 , ICs7.ir.RSSD.LC71) = o. 37 Maximum interaction coefficient for Member 57, Load Combination 7-1 MFs7.ir.LC71 := - C

__I_ _ = 2.70 Margin factor for Member 57, Load 1 57.ir.LC71 Combination 7-1

Analysis No. L-002547 Revision No. OA Page 54 7.1.5.3 Evaluate Load Combination 7-2 Fa.Th.190 := IF19o*Fa.Th.146 = Sl.21-kip Axial load and moment components due to thermal load, prorated for 190°F MB.Th.190 := IF19o*Ma.Th.14 6 = 2.54*ft-kip Mc.Th.190 := IF19o*Mc.Th.14 6 = 10.0l*ft*kip SRV loads are reduced to 40% of the full load per Section 6.1.2.1. Per the previous section, SVSA controls.

Design axial load on brace, Load Combination 7-2:

Fa.tot.72 := Fa.DL + Fa.Th.190 + 'YSRV.72Fa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = 245 -17 *kip Design moment on brace, Load Combination 7-2:

MB.72 := MB.Th.190 + MB.LOCA.lat.db + MB.LOCA.drag.db + 'YSRV.n*Ma.SVSA *** = 74 -0 6 -ft*kip

+ elb.57.h*Fa.tot.72 Mc.72 := Mc.Th.190 + Mc.LOCA.lat.db + Mc.LOCA.drag .db + -YsRv.n*Mc.s vsA = 48.13-ft,kip Fa.tot.72 .

fa.57.ir.72 := A = 12.12*ks1 Axial stress on brace, Load Combination 7-2 lb MR.tot.72 .

fb.57.ir.72 := Z = 22.53-kst Bending stress on brace, Load Combination 7-2 lb fa.57.ir.72 fb.57.ir.72 ICs7.ir.LC72 := - - - + - - - = 0.66 Interaction coefficient for Member 57, Load Fa.LB Fb.LB Combination 7-2 1

MFs7.ir.LC72 := I ICs7.ir.LC72

= 1.s1 Margin factor for Member 57, Lo1d Combination 7-2

Analysis No. L-002547 Revision No. OA Page 55 7.1.5.4 Evaluate Load Combination 7-3 Fa.Th.ISO:= IFiso-Fa.Th.146 = 34.I2*kip Axial load and moment components due to MB.Th.150 := IFiso*MB.Th.I46 = 1.69-ft-kip thermal load, prorated for 150°F Mc.Th.ISO:= IFiso*Mc.Th.I46 = 6.67-ft-kip SRV loads are reduced per Section 6.1.2.1. Both SVSA and RSSD are checked since the loads are similar.

Design axial load on brace, Load Combination 7-3:

Fa.SVSA.ISO := Fa.DL +Fa.Th.ISO+ "YSVSA Fa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = 24 I*kip Fa.RSSD.ISO := Fa.DL +Fa.Th.ISO+ "YRSSDFa.RSSD + Fa.LOCA +Fa.DRAG+ Fa.Ess = 247.68-kip MB.73 := MB.Th.150 + MB.LOCA.lat.db + MB.LOCA.drag.db = ?.OS*ft*kip Mc.73 :=Mc.Th.ISO+ Mc.LOCA.lat.db + Mc.LOCA.drag.db = 39. 29-ft-kip Design moment on brace, 150°F temperature case, with SRV-SVSA:

I . 2 .

MR.SVSA.lSO := MR.DL + {MB.73 + "YSVSA MB.SVSA + elb.S7.h*Fa.SVSA.1SO) ...... = 92.83*ft*kip

~ + (Mc.73 + "YSVSA Mc.svsA) 2

+ MR.DRAG+ MR.Ess Design moment on brace, 150°F temperature case, with SRV-RSSD:

2 2 MR.RSSD.lSO := MR.DL + "YRSSDMR.RSSD + j{MB.73 + elb.57.h*Fa.RSSD.ISo) + Mc.73 ... = 9S.67*ft*kip

+ MR.DRAG + MR.Ess Fa.SVSA.ISO fa.57.ir.SVSA.73 ( Alb = I l.9I-ksi Axial stress on brace, Load Combination 7-3, with SRV-SV~

MR.SVSA.ISO .

fb.57.ir.SVSA.73 := z = 22.36-ksi Bending stress on brace, Load lb Combination 7-3, with SRV-SV~

IC . *= fa.57.ir.SVSA.73 + fb.57.ir.SVSA.73 = 0 _66 Interaction coefficient for 57.rr.SVSA.LC73

• Fa.LB Fb.LB Member 57, Load Combination 7-3, with SRV-SV~

Analysis No. L-002547 Revision No. OA Page 56 Fa.RSSD.150 fa.57.ir.RSSD.73 := A = 12.24-ksi Axial stress on brace, Load Combination lb 7-3, with SRV-RSSD MR.RSSD.150 fb.57.ir.RSSD.73 := z = 23.04-ksi Bending stress on brace, Load lb Combination 7-3, with SRV-RSSD fa.57.ir.RSSD.73 fb.57.ir.RSSD.73 IC 57.ir.RSSD.LC73 := F + = 0.68 Interaction coefficient for a.LB Fb.LB Member 57, Load Combination 7-3, with SRV-RSSD ICs7.ir.LC73 := max(IC57_ir.SVSA.LC73, ICs7.ir.RSSD.LC73) = 0. 68 Maximum interaction coefficient for Member 57, Load Combination 7-3 I

MFs7.ir.LC73 := - - - - = 1.48 Margin factor for Member 57, Load ICs7.ir.LC73 Combination 7-3

Analysis No. L-002547 Revision No. OA Page 57

7. 1.6 Member 47 I Node 35 7.1.6.1 Determine Current Design Loading Ref. 3a, Section 4.5 and Ref. 3b, Section 6.2.1 identify Member 47 as a critical lower bracing member for the Inner Ring bracing. Loads on the member are identified below.

Fa.DL := 0kip MR.DL := 0.015ft-kip Axial load and moment due to dead load (Ref. 3a, Section 4.5, page 4)

Fa.Th.146 := 22.34kip MR.Th.146 := 15.87ft*kip Axial load and moment due to thermal load, 146°F (Ref. 3a, Section 4.5, page 4)

Fa.SVSA := 26.01 kip MR.SVSA := 11.11 ft* kip Axial load and moment due to SRV-SVSA.

(Ref. 3a, Section 4.5, page 3)

Fa.RSSD := 32.47kip MR.RSSD := 11.48ft* kip Axial load and moment due to SRV-RSSD (Ref. 3a, Section 4.5, page 3)

Fa.LOCA := max(24.62 ,21.320)*kip + 105.39kip = 130.01-kip Axial load due to LOCA (Ref. 3a, Section 4.5, page 4; Ref. 3b, Section 6.2.1, page 3)

Moment load due to LOCA (Ref. 3a, Section 4.5, page 4; Ref. 3b, Section 6.2.1, page 3):

MR.LOCA := max(14.56,3.330)*ft*kip+48.79ft*kip = 63.35-ft*kip Fa.DRAG := 0kip MR.DRAG := 0.29ft* kip Axial load and moment due to bracing drag (SVSA or RSSD + Chugging) (Ref. 3a, Section 4.5, page 4)

Fa.Ess := 0kip MR.Ess := 3.02ft-kip Axial load and moment due to seismic (Ref. 3a, Section 4.5, page 4)

Per Design Input #5, Member 47 was installed within tolerance, thus no additional moment needs to be added for the eccentricity.

elb.47 = 0-in Maximum eccentricity of a CBI brace number equivalent to Member 47 (previously specified)

Analysis No. L-002547 Revision No. OA Page 58 7.1.6.2 Evaluate Load Combination 7-1 Fa.Th.212 := IF212*Fa.Th.146 = 4 L7S-kip Axial load and moment due to thermal load, prorated for 212°F MR.Th.212 := IF212"MR.Th.146 = 29.68-ft*kip Design axial load on brace, Load Combination 7-1:

Fa.tot.71 := Fa.DL + Fa.Th.212 + Fa.RSSD +Fa.DRAG+ Fa.Ess = 74 -25 *kip Design moment on brace, Load Combination 7-1:

MR.tot.71 := MR.DL + MR.Th.212 + MR.RSSD +MR.DRAG+ MR.Ess = 44.4S*ft*kip f 47. 71 *- Fa.tot.71 = 3.67-ksi Axial stress on brace, Load Combination 7-1

a. .rr. .- Alb MR.tot.71 .

fb.47.ir.71 := z = 10.7l*ks1 Bending stress on brace, Load Combination 7-1 lb fa.47.ir.71 fb.47.ir.71 IC47.ir.LC71 := - - - + - - - = 0.28 Interaction coefficient for Member 4 7, Load Fa.LB Fb.LB Combination 7-1 l

MF47.ir.LC71 := IC = 3.63 Margin factor for Member 4 7, Load 47.ir.LC71 Combination 7-1

Analysis No. L-002547 Revision No. OA Page 59 7.1.6.3 Evaluate Load Combination 7-2 Fa.Th.190 := IF19o*Fa.Th.146 = 3S.3-kip Axial load and moment due to thermal load, MR.Th.190 := IF19o*MR.Th.146 = 25.07-ft-kip prorated for 190°F SRV loads are reduced to 40% of the full load per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-2:

Fa.tot.72 := Fa.DL + Fa.Th.190 + "ISRV.72Fa.RSSD + Fa.LOCA +Fa.DRAG+ Fa.Ess = 178 kip Design moment on brace, Load Combination 7-2:

MR.tot.72 := MR.DL + MR.Th.190 + "ISRV.72MR.RSSD + MR.LOCA +MR.DRAG+ MR.Ess = 96 .34-ft-kip Fa.tot.72 fa.47.ir.72 := A = 8.81-ksi Axial stress on brace, Load Combination 7-2 lb MR.tot.72 fb.47.ir.72 := z = 23.2-ksi Bending stress on brace, Load Combination 7-2 lb fa.47.ir.72 fb.47.ir.72 IC47.ir.LC72 := F + = 0.61 Interaction coefficient for Member 4 7, Load a.LB Pb.LB Combination 7-2 1

MF47.ir.LC72 := - - - - = 1.63 Margin factor for Member 47, Load IC47.ir.LC72 Combination 7-2

Analysis No. L-002547 Revision No. OA Page 60 7.1.6.4 Evaluate Load Combination 7-3 Fa.Th.ISO:= IFiso-Fa.Th.I46 = 23.S2*kip Axial load and moment due to thermal load, MR.Th.150 := IFiso*MR.Th.I46 = I6.7I*ft*kip prorated for 150°F SRV loads are reduced per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-3:

Fa.SVSA.ISO := Fa.DL +Fa.Th.ISO+ 'YSVSA Fa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = I7L 73 *kip Fa.RSSD. ISO := Fa.DL +Fa.Th.ISO+ 'YRSSDFa.RSSD + Fa.LOCA +Fa.DRAG+ Fa.Ess = I 79.5 *kip Design moment on brace, 150°F temperature case, with SRV-SVSA:

MR.SVSA.ISO := MR.DL +MR.Th.ISO+ 'YSVSA MR.SVSA + MR.LOCA +MR.DRAG+ MR.Ess = 91.1 6 *ft*kip Design moment on brace, 150°F temperature case, with SRV-RSSD:

MR.RSSD.ISO := MR.DL +MR.Th.ISO+ 'YRSSDMR.RSSD + MR.LOCA +MR.DRAG+ MR.Ess = 92.56*ft*kip As shown, RSSD controls.

Fa.RSSD.ISO .

f 47

• 73 := - - - - = 8.87*ks1 Axial stress on brace, Load Combination 7-3

a. .rr. Alb MR.RSSD.ISO .

fb.47.ir.73 := z = 22.29*ks1 Bending stress on brace, Load Combination 7-3 lb fa.47.ir.73 fb.47.ir.73 IC47.ir.LC73 := - - - + - - - = 0.60 Interaction coefficient for Member 4 7, Load Fa.LB Fb.LB Combination 7-3 1

MF47.ir.LC73 := IC = 1. 68 Margin factor for Member 4 7, Load 47.ir.LC73 Combination 7-3

Analysis No. L-002547 Revision No. OA Page 61 7.2 LOWER DOWNCOMER BRACING, OUTER RING For the 105% power uprate, the thermal load is increased based on the elevated Suppression Pool temperature. All other loads remain the same. Per Ref. 3a, Section 4.5 and Ref. 3c, Section 7 .3.2.2, the following members were previously qualified and are re-analyzed herein:

• Member 126 / Node 100

• Member 41 / Node 31

• Member 101 / Node 73

• Member 104 / Node 100

• Member 40 / Node 22

• Member 67 / Node 51 7.2.1 Member 126/ Node 100 7.2.1.1 Determine Current Design Loading Ref. 3a, Section 4.5 and Ref. 3b, Section 6.2.2 identify Member 126 as a critical lower bracing member for the Outer Ring bracing. Loads on the member are identified below. The loads are taken as the maximum from Ref. 3a, Section 4.5, page 5 or Ref. 3b, Section 6.2.2, page 2.

RSSD does not control for SRV loading per Ref. 3a, Section 4.5, page 5.

Fa.DL := Okip MR.DL := 0.165ft,kip Axial load and moment due to dead load Fa.Th.146 := 62.3kip MR.Th.146 := 56.95ft-kip Axial load and moment due to thermal load, 146°F Fa.SVSA := 35.92kip MR.SVSA := 7.323ft-kip Axial load and moment due to SRV-SV~

Fa.LOCA := max(49.81,45.33)*k ip + 35.34kip = 85.15-kip Axial load due to LOCA MR.LOCA := max(13.82, 8.33)-ft-kip + I l.13ft*kip = 24.95-ft-kip Moment due to LOCA Fa.DRAG := Okip MR.DRAG:= 1.64ft-kip Axial load and moment due to bracing drag (SVSA or RSSD + Chugging)

Fa.Ess := Okip MR.Ess := 2.67ft, kip Axial load and moment due to seismic Per Design Input #5, Member 126 was installed within tolerance, thus no additional moment needs to be added for the eccentricity.

elb.1260 = O* in Maximum eccentricity of a CBI brace number equivalent to Member 126 (previously specified)

Analysis No. L-002547 Revision No. OA Page 62 7.2.1.2 Evaluate Load Combination 7-1 Fa.Th.212 := IF212*Fa.Th.146 = 116.S-kip Axial load and moment due to thermal load, prorated for 212°F MR.Th.212 := IF212*MR.Th.146 = 106.S-ft-kip Design axial load on brace, Load Combination 7-1:

Fa.tot.71 := Fa.DL + Fa.Th.212 + Fa.SVSA +Fa.DRAG+ Fa.Ess = lS 2.42-kip Design moment on brace, Load Combination 7-1:

MR.tot.71 := MR.Th.212 + MR.SVSA + MR.DL +MR.DRAG+ MR.Ess = 118.29-ft-kip Fa.tot.71 fa.126.or.71 := A = 7.53-ksi Axial stress on brace, Load Combination 7-1 lb MR.tot.71 .

fb.126.or.71 := Z = 28.49-ksi Bending stress on brace, Load Combination 7-1 lb fa.126.or.71 fb.126.or.71 IC126.or.LC71 := - - - - + - - - - = 0.69 Interaction coefficient for Member 126, Load Fa.LB Fb.LB Combination 7-1 1

MF126.or.LC71 :=-IC _ _ _ _ _ = 1.45 Margin factor for Member 126, Load 126.or.LC71 Combination 7-1

Analysis No. L-002547 Revision No. OA Page 63 7.2.1.3 Evaluate Load Combination 7-2 Fa.Th.190 := IF19o*Fa.Th.146 = 98.43-kip Axial load and moment due to thermal load, prorated for 190°F MR.Th.190 := IF19o*MR.Th.146 = 89.98-ft-kip SRV loads are reduced to 40% of the full load per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-2:

Fa.tot.72 := Fa.DL + Fa.Th.190 + 1SRV.72Fa.SV SA + Fa.LOCA +Fa.DRAG+ Fa.Ess = 197.95-kip Design moment on brace, Load Combination 7-2:

MR.tot.72 := MR.Th.190 + 1SRV.72MR.SV SA + MR.LOCA + MR.DL +MR.DRAG+ MR.Ess = 122.34-ft*kip Fa.tot.72 .

fa.126.or.72 := A = 9.79*ks1 Axial stress on brace, Load Combination 7-2 lb MR.tot.72 fb.126.or.72 := Z = 29.46-ksi Bending stress on brace, Load Combination 7-2 lb fa.126.or.72 fb.126.or.72 IC126.or.LC72 := - - - - + - - - - = 0.75 Interaction coefficient for Member 126, Load Fa.LB Fb.LB Combination 7-2 I

MF126.or.LC72 := - - - - - = 1.33 Margin factor for Member 126, Load IC126.or.LC72 Combination 7-2

Analysis No. L-002547 Revision No. OA Page 64 7.2.1.4 Evaluate Load Combination 7-3 Fa.Th.150 := IF15o*Fa.Th.146 = 65.58 -kip Axial load and moment due to thermal load, prorated for 150°F MR.Th.150 := IF1so*MR.Th.146 = 59.95-ft*kip SRV loads are reduced per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-3:

Fa.tot.73 := Fa.DL + Fa.Th.150 + "'fSVSAFa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = l75.87*kip Design moment on brace, Load Combination 7-3:

MR.tot.73 := MR.Th.150 + "'fSVSAMR.SVSA + MR.LOCA + MR.DL +MR.DRAG+ MR.Ess = 94.S*ft-kip Fa.tot.73 .

fa.126 .or.73 := A = 8.69-ksi Axial stress on brace, Load Combination 7-3 lb MR.tot.73 .

fb.126.or.73 := Z = 22.76-ksi Bending stress on brace, Load Combination 7-3 lb fa.126.or.73 fb.126.or.73 IC126.or.LC73 := - - - - + - - - - = 0.60 Interaction coefficient for Member 126, Load Fa.LB Fb.LB Combination 7-3 1

MF126.or.LC73 := - - - - - = 1.66 Margin factor for Member 126, Load IC 126.or.LC73 Combination 7-3

Analysis No. L-002547 Revision No. OA Page 65 7.2.2 Member 41 I Node 31 7.2.2.1 Determine Current Design Loading Ref. 3a, Section 4.5 and Ref. 3b, Section 6.2.2 identify Member 41 as a critical lower bracing member for the Outer Ring bracing. Loads on the member are identified below. The loads are taken as the maximum from Ref. 3a, Section 4.5, page 5 or Ref. 3b, Section 6.2.2, page 3.

RSSD does not rontrol for SRV loading per Ref. 3a, Section 4.5, page 5.

Fa.DL := Okip MR.DL := 0.165ft-kip Axial load and moment due to dead load Fa.Th.146 := 39.0lkip MR.Th.146 := 61.33ft-kip Axial load and moment due to thermal load, 146°F Fa.SVSA := 30.698kip MR.SVSA := 9.907ft-kip Axial load and moment due to SRV-SV~

Note that Ref 3b, Section 6.2.2, page 3 misidentifies the rontrolling axial force and moment for LOCA lateral chugging. See Ref. 3b, Section 6.2.2, page 1 for the rontrolling values.

Fa.LOCA := max(53.26,54.180)-kip+28.21kip = 82.39-kip Axial load due to LOCA MR.LOCA := max(14.74 ,23.699)-ft-kip + 12.0lft-kip = 35.71-ft-kip Moment due to LOCA Fa.DRAG := Okip MR.DRAG:= l.64ft-kip Axial load and moment due to bracing drag (SVSA or RSSD + Chugging)

Fa.Ess := Okip MR.Ess := 2.2ft, kip Axial load and moment due to seismic Per Design Input #5, Member 41 was installed out of tolerance, thus additional moment needs to be added for the eccentricity.

elb.41 = 0.65 in Maximum eccentricity of a CBI brace number equivalent to Member 41 (previously specified)

Analysis No. L-002547 Revision No. OA Page 66 7.2.2.2 Evaluate Load Combination 7-1 Fa.Th.212 := IF212*Fa.Th.146 = 72.95-kip Axial load and moment due to thermal load, prorated for 212°F MR.Th.212 := IF212*MR.Th.146 = 114.69-ft-kip Design axial load on brace, Load Combination 7-1:

Fa.tot.71 := Fa.DL + Fa.Th.212 + Fa.SVSA +Fa.DRAG+ Fa.Ess = 103.65 -kip Design moment on brace, Load Combination 7-1:

MR.tot.71 := MR.Th.212 + MR.SVSA + MR.DL +MR.DRAG+ MR.Ess = 128.6-ft-kip

• - Fa.tot.71 f a.41 .or. 71

.- -Alb

-- = 5.12-ksi Axial stress on brace, Load Combination 7-1

• - MR.tot.71 + Fa.tot.71'elb.41 f,

. 1.or. 71 .- - - - - z b4 - - - - - = 32.32-ksi Bending stress on brace, Load Combination 7-1 lb fa.41.or. 71 fb.41.or. 71 IC41.or.LC71 := + - - - - = 0.72 Interaction coefficient for Member 41, Load Fa.LB Fb.LB Combination 7-1 1

MF41.or.LC71 := -IC_4_1-.o-r-.L-C_7_1 = 1.40 Margin factor for Member 41, Load Combination 7-1

Analysis No. L-002547 Revision No. OA Page 67 7.2.2.3 Evaluate Load Combination 7-2 Fa.Th.190 := IF19o*Fa.Th.146 = 6 1.64-kip Axial load and moment due to thermal load, prorated for 190°F MR.Th.190 := IF19o*MR.Th.146 = 96.9-ft-kip SRV loads are reduced to 40% of the full load per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-2:

Fa.tot.72 := Fa.DL + Fa.Th.190 + "'ISRV.72Fa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = lS 6.3l-kip Design moment on brace, Load Combination 7-2:

MR.tot.72 := MR.Th.190 + "'ISRV.72MR.SVSA + MR.LOCA + MR.DL +MR.DRAG+ MR.Ess = 140.SS*ft*kip Fa.tot.72 .

fa.41.or.72 := A = 7.73-ksi Axial stress on brace, Load Combination 7-2 lb r *- MR.tot.72 + Fa.tot.72'elb.41 1 b41

. .or. 72 .- - - - - Zlb - - - - - = 35.89-ksi Bending stress on brace, Load Combination 7-2 fa.41.or.72 fib .41.or.72 IC4 l.or.LC72 := - - - - + - - - - = 0.83 Interaction coefficient for Member 41, Load Fa.LB Fb.LB Combination 7-2 1

MF4 l.or.LC72 := - - - - = 1.20 Margin factor for Member 41, Load IC4l.or.LC72 Combination 7-2

Analysis No. L-002547 Revision No. OA Page 68 7.2.2.4 Evaluate Load Combination 7-3 Fa.Th.150 := IF150-Fa.Th.146 = 4 1.06-kip Axial load and moment due to thermal load, prorated for 150°F MR.Th.150 := IF15o*MR.Th.146 = 64.56-ft-kip SRV loads are reduced per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-3:

Fa.tot.73 := Fa.DL + Fa.Th.150 + 'YSVSAFa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = 144 .94 .kip Design moment on brace, Load Combination 7-3:

MR.tot.73 := MR.Th.150 + 'YSVSAMR.SVSA + MR.LOCA + MR.DL +MR.DRAG+ MR.Ess = l l l. 2 1 *ft*kip Fa.tot.73 .

fa.41.or.73 := A = 7.16-kst Axial stress on brace, Load Combination 7-3 lb MR.tot.73 .

fb.41.or.73 := Z = 26.78-kst Bending stress on brace, Load Combination 7-3 lb fa.41.or.73 fb.41.or.73 IC41.or.LC73 := - - - + - - - - = 0.65 Interaction coefficient for Member 41, Load Fa.LB Fb.LB Combination 7-3 1

MF4 l.or.LC73 := - - - - = 1.54 Margin factor for Member 41, Load IC41.or.LC73 Combination 7-3

Analysis No. L-002547 Revision No. OA Page 69 7.2.3 Member 101 I Node 73 7.2.3.1 Determine Current Design Loading Ref. 3a, Section 4.5 and Ref. 3b, Section 6.2.2 identify Member 101 as a critical lower bracing member for the Outer Ring bracing. Loads on the member are identified below. The loads are taken as the maximum from Ref. 3a, Section 4.5, page 6 or Ref. 3b, Section 6.2.2, page 4.

RSSD does not control for SRV loading per Ref. 3a, Section 4.5, page 5.

Fa.DL := Okip MR.DL := O.Olft-kip Axial load and moment due to dead load Fa.Th. I 46 := 2 l.28kip MR.Th.146 := 7.30ft-kip Axial load and moment due to thermal load, 146°F Fa.SVSA := 13.49kip MR.SVSA := 29.20ft*kip Axial load and moment due to SRV-SV~

Fa.LOCA := max(23.18, 30.49)-kip + 18.87kip = 49.36-kip Axial load due to LOCA MR.LOCA := max(l 1.49, 36.46)-ft*kip + 29.0lft-kip = 65.47-ft*kip Moment due to LOCA Fa.DRAG := Okip MR.DRAG:= O.ISft-kip Axial load and moment due to bracing drag (SVSA or RSSD + Chugging)

Fa.Ess := Okip MR.Ess := 5.47ft-kip Axial load and moment due to seismic Per Design Input #5, Member 101 was not installed out of tolerance, thus no additional moment needs to be added for the eccentricity.

elb.101 = O*in Maximum eccentricity of a CBI brace number equivalent to Member 101 (previously specified)

Analysis No. L-002547 Revision No. 0A Page 70 7.2.3.2 Evaluate Load Combination 7-1 Fa.Th.212 := IF212*Fa.Th.146 = 39.79-kip Axial load and moment due to thermal load, prorated for 212°F MR.Th.212 := IF212*MR.Th.146 = 13.65-ft-kip Design axial load on brace, Load Combination 7-1:

Fa.tot.71 := Fa.DL + Fa.Th.212 + Fa.SVSA +Fa.DRAG+ Fa.Ess = 53.28-kip Design moment on brace, Load Combination 7-1:

MR.tot.71 := MR.DL + MR.Th.212 + MR.SVSA +MR.DRAG+ MR.Ess = 48.48-ft*kip f *- Fa.tot.?} = 2.63-ksi Axial stress on brace, Load Combination 7-1 a.101.or.71 .- A lb MR.tot.71 .

fb.101.or.71 := Z = l l.68*ks1 Bending stress on brace, Load Combination 7-1 lb

• = fa.101.or.71 fb.101.or.71 IC 101.or.LC71

• F + = 0.27 Interaction coefficient for Member 101, Load a.LB Fb.LB Combination 7-1 I

MF101.or.LC71 :=-IC_ _ _ _ = 3.65 Margin factor for Member 101, Load 101.or.LC71 Combination 7-1

Analysis No. L-002547 Revision No. OA Page 71 7.2.3.3 Evaluate Load Combination 7-2 Fa.Th.190 := IF19o*Fa.Th.146 = 33.62-kip Axial load and moment due to thermal load, prorated for 190°F MR.Th.190 := IF19o*MR.Th.146 = 11.53-ft-kip SRV loads are reduced to 40% of the full load per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-2:

Fa.tot.72 := Fa.DL + Fa.Th.190 + "fSRV.72Fa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = 88 kip Design moment on brace, Load Combination 7-2:

MR.tot.72 := MR.DL + MR.Th.190 + "fSRV.72MR.SVSA + MR.LOCA +MR.DRAG+ MR.Ess = 94.31-ft-kip F a.tot.72 .

fa.101.or.72 := A = 4.37-ksi Axial stress on brace, Load Combination 7-2 lb MR.tot.72 .

fb.101.or.72 := Z = 22.71-ksi Bending stress on brace, Load Combination 7-2 lb fa.101.or.72 fib .101.or.72 IC10 l.or.LC72 := - - - - + - - - - = 0.52 Interaction ooefficient for Member 101, Load Fa.LB Fb.LB Combination 7-2 MF101.or.LC72 := - - - - - = 1.93 Margin factor for Member 101, Load IC 10 l.or.LC72 Combination 7-2

Analysis No. L-002547 Revision No. OA Page 72 7.2.3.4 Evaluate Load Combination 7-3 Fa.Th.ISO:= IF15o*Fa.Th.146 = 22 .4-kip Axial load and moment due to thermal load, prorated for 150°F MR.Th.ISO:= IF1so*MR.Th.146 = 7.68-ft-kip SRV loads are reduced per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-3:

Fa.tot.73 := Fa.DL +Fa.Th.ISO+ "'YSVSAFa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = 81.2-kip Design moment on brace, Load Combination 7-3:

MR.tot.73 := MR.DL +MR.Th.ISO+ "'YSVSAMR.SVSA + MR.LOCA +MR.DRAG+ MR.Ess = 99.22* ft*kip Fa.tot.73 fa.101.or.73 := A = 4.01-ksi Axial stress on brace, Load Combination 7-3 lb MR.tot.73 .

fb.101.or.73 := Z = 23.9-ksi Bending stress on brace, Load Combination 7-3 lb fa.101 .or.73 fib . 101 .or. 73 IC101.or.LC73 := + - - - - = 0.53 Interaction coefficient for Member 101, Load Fa.LB Fb.LB Combination 7-3 MF10I.or.LC73 := - - - - - = 1.87 Margin factor for Member 101, Load ICtOI.or.LC73 Combination 7-3

Analysis No. L-002547 Revision No. OA Page 73 7.2.4 Member 1041 Node 100 7.2.4.1 Determine Current Design Loading Ref. 3a, Section 4.5 and Ref. 3b, Section 6.2.2 identify Member 104 as a critical lower bracing member for the Outer Ring bracing. Loads on the member are identified below. The loads are taken as the maximum from Ref. 3a, Section 4.5, page 5 or Ref. 3b, Section 6.2.2, page 2.

RSSD does not control for SRV loading per Ref. 3a, Section 4.5, page 5.

Fa.DL := Okip MR.DL := 0.127ft, kip Axial load and moment due to dead load Fa.Th.146 := 65.Skip MR.Th.146 := 6.21ft-kip Axial load and moment due to thermal load, 146°F Fa.SVSA := 24.92kip MR.SVSA := 9.19ft-kip Axial load and moment due to SRV-SVSA Fa.LOCA := max(40.31, 17.45)-kip + 37.08kip = 77.39-kip Axial load due to LOCA MR.LOCA := max(20.94,2.29 )*ft*kip + 12.18ft-kip = 33.12-ft-kip Moment due to LOCA Fa.DRAG := Okip MR.DRAG := 1.27ft. kip Axial load and moment due to bracing drag (SVSA or RSSD + Chugging)

Fa.Ess := Okip MR.Ess := 2.93ft*kip Axial load and moment due to seismic Per Design Input #5, Member 104 was installed within tolerance, thus no additional moment needs to be added for the eccentricity.

elb.104 = O Maximum eccentricity of a CBI brace number equivalent to Member 104 (previously specified)

Analysis No. L-002547 Revision No. OA Page 74 7.2.4.2 Evaluate Load Combination 7-1 Fa.Th.212 := IF212*Fa.Th.146 = 122.49-kip Axial load and moment due to thermal load, prorated for 212°F MR.Th.212 := IF212*MR.Th.146 = l 1.6l*ft*kip Design axial load on brace, Load Combination 7-1:

Fa.tot.71 := Fa.DL + Fa.Th.212 + Fa.SVSA +Fa.DRAG+ Fa.Ess = 14 7.41-kip Design moment on brace, Load Combination 7-1:

MR.tot.71 := MR.DL + MR.Th.212 + MR.SVSA +MR.DRAG+ MR.Ess = 25.13-ft*kip Fa.tot.71 fa.104.or.71 := A = 7.29-ksi Axial stress on brace, Load Combination 7-1 lb MR.tot.71 fb .104.or.71 := Z = 6.05-ksi Bending stress on brace, Load Combination 7-1 lb

• - fa.104.or.71 fb.104.or.71 IC 104.or.LC71 .- F + = 0*26 Interaction coefficient for Member 104, Load a.LB Fb.LB Combination 7-1 MF 104

.or.

LC71 *- - - - - -

.- IC104.or.LC71

= 3.92 Margin factor for Member 104, Load Combination 7-1

Analysis No. L-002547 Revision No. OA Page 75 7.2.4.3 Evaluate Load Combination 7-2 Fa.Th.190 := IF 190* F a.Th.146 = 103 .49. kip Axial load and moment due to thermal load, prorated for 190°F MR.Th.190 := IF19o*MR.Th.146 = 9.81-ft*kip SRV loads are reduced to 40% of the full load per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-2:

Fa.tot.72 := Fa.DL + Fa.Th.190 + "ISRV.72Fa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = 190.85-kip Design moment on brace, Load Combination 7-2:

MR.tot.72 := MR.DL + MR.Th.190 + "ISRV.72MR.SVSA + MR.LOCA + MR.DRAG+ MR.Ess = S0.93-ft-kip Fa.tot.72 .

fa.104.or.72 := A = 9.43-ksi Axial stress on brace, Load Combination 7-2 lb MR.tot.72 .

fb.104.or.72 := Z = 12.27-ksi Bending stress on brace, Load Combination 7-2 lb fa.104.or.72 f, b.104.or.72 IC 104.or.LC72 := - - - - + - - - - = 0.42 Interaction coefficient for Member 104, Load Fa.LB Fb.LB Combination 7-2 1

MF 104.or.LC72 := - - - - - = 2.41 Margin factor for Member 104, Load IC104.or.LC72 Combination 7-2

Analysis No. L-002547 Revision No. OA Page 76 7.2.4.4 Evaluate Load Combination 7-3 Fa.Th.150 := IF15o*Fa.Th.146 = 68.95-kip Axial load and moment due to thermal load, prorated for 150°F MR.Th.150 := IF15o*MR.Th.146 = 6.54-ft-kip SRV loads are reduced per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-3:

Fa.tot.73 := Fa.DL + Fa.Th.150 + "fSVSAFa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = 163.78-kip Design moment on brace, Load Combination 7-3:

MR.tot.73 := MR.DL + MR.Th.150 + "fSVSAMR.SVSA + MR.LOCA +MR.DRAG+ MR.Ess = 50.42* ft-kip F

f *- a.tot.73 = 8.1 *ksi Axial stress on brace, Load Combination 7-3 a.104.or.73 .- Alb MR.tot.73 fb.104.or.73 := Z = 12.14-ksi Bending stress on brace, Load Combination 7-3 lb fa.104.or.73 fb.104 .or.73 ICt04.or.LC73 := + - - - - = 0.39 Interaction coefficient for Member 104, Load Fa.LB Fb.LB Combination 7-3 MF 104.or.LC73 := - - - - - = 2.58 Margin factor for Member 104, Load IC l04.or.LC73 Combination 7-3

Analysis No. L-002547 Revision No. OA Page 77

7. 2.5 Member 40 I Node 22 7.2.5.1 Determine Current Design Loading Ref. 3a, Section 4.5 and Ref. 3b, Section 6.2.2 identify Member 40 as a critical lower bracing member for the Outer Ring bracing. Loads on the member are identified below. The loads are taken as the maximum from Ref. 3a, Section 4.5, page 5 or Ref. 3b, Section 6.2.2, page 2.

RSSD does not control for SRV loading per Ref. 3a, Section 4.5, page 5.

Fa.DL := 0kip MR.DL := 0.015ft* kip Axial load and moment due to dead load Fa.Th.146 := 29.20kip MR.Th.146 := I l.25ft*kip Axial load and moment due to thermal load, 146°F Fa.SVSA := 19.47kip MR.SVSA := 31.20ft, kip Axial load and moment due to SRV-SV~

Fa.LOCA := max( 41.14, 23.0)*kip + 25.00kip = 66.14-kip Axial load due to LOCA MR.LOCA := max(24.58, 15.66),ft*kip + 28.ISft*kip = 52.76-ft-kip Moment due to LOCA Fa.DRAG := Okip MR.DRAG:= 0.15ft*kip Axial load and moment due to bracing drag (SVSA or RSSD + Chugging)

F a.Ess := Okip MR.Ess := 5.47ft-kip Axial load and moment due to seismic Per Design Input #5, Member 40 was installed out of tolerance, thus additional moment needs to be added for the eccentricity.

elb.40 = 0.25 in Maximum eccentricity of a CBI brace number equivalent to Member 40 (previously specified)

Analysis No. L-002547 Revision No. OA Page 78 7.2.5.2 Evaluate Load Combination 7-1 Fa.Th.212 := IF212*Fa.Th.146 = 54.6-kip Axial load and moment due to thermal load, prorated for 212°F MR.Th.212 := IF212*MR.Th.146 = 21.0 4 -ft*kip Design axial load on brace, Load Combination 7-1:

Fa.tot.71 := Fa.DL + Fa.Th.212 + Fa.SVSA +Fa.DRAG+ Fa.Ess = 74.07-kip Design moment on brace, Load Combination 7-1:

MR.tot.71 := MR.DL + MR.Th.212 + MR.SVSA +MR.DRAG+ MR.Ess = 57.87-ft-kip Fa.tot.71 fa.40.or.71 := A = 3.66-ksi Axial stress on brace, Load Combination 7-1 lb

£ MR.tot.71 + F a.tot.71' elb.40 .

1 b.40.or.71 := Z = 14.31*ks1 Bending stress on brace, Load Combination 7-1 lb

• = fa.40.or.71 fb.40.or.71 IC40.or.LC71

• F + = 0.34 Interaction coefficient for Member 40, Load a.LB Fb.LB Combination 7-1 1

MF40.or.LC71 :=-IC _ _ _ _ = 2.91 Margin factor for Member 40, Load 40.or.LC71 Combination 7-1

Analysis No. L-002547 Revision No. OA Page 79 7.2.5.3 Evaluate Load Combination 7-2 Fa.Th.190 := IF19o*Fa.Th.146 = 46.14-kip Axial load and moment due to thermal load, prorated for 190°F MR.Th.190 := IF19o*MR.Th.146 = 17.78-ft-kip SRV loads are reduced to 40% of the full load per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-2:

Fa.tot.72 := Fa.DL + Fa.Th.190 + 1SRV.72 Fa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = 120,0 6 *kip Design moment on brace, Load Combination 7-2:

MR.tot.72 := MR.DL + MR.Th.190 + 1SRV.72MR.SVSA + MR.LOCA +MR.DRAG+ MR.Ess = 88.65-ft-kip Fa.tot.72 fa.40.or.72 := A = 5.93 -ksi Axial stress on brace, Load Combination 7-2 lb MR.tot.72 + Fa.tot.12*e1b.40 .

f,b.40.or.72 := Z = 21.95-ksi Bending stress on brace, Load Combination 7-2 lb fa.40.or.72 fb.40.or.72 I C40.or.LC72 := - - - - + - - - = 0.53 Interaction coefficient for Member 40, Load Fa.LB Fb.LB Combination 7-2 1

MF40.or.LC72 := - - - - = 1.87 Margin factor for Member 40, Load IC40.or.LC72 Combination 7-2

Analysis No. L-002547 Revision No. OA Page 80 7.2.5.4 Evaluate Load Combination 7-3 Fa.Th.ISO:= IF15o*Fa.Th.146 = J0.74-kip Axial load and moment due to thermal load, prorated for 150°F MR.Th.150 := IF15o*MR.Th.146 = 11.84-ft-kip SRV loads are reduced per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-3:

Fa.tot.73 := Fa.DL +Fa.Th.ISO+ 'YSVSAFa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = llO.Sl-kip Design moment on brace, Load Combination 7-3:

MR.tot.73 := MR.DL +MR.Th.ISO+ 'YSVSAMR.SVSA + MR.LOCA +MR.DRAG+ MR.Ess = 92 -08* ft-kip Fa.tot.73 .

fa.40.or.73 := A = 5.46-kst Axial stress on brace, Load Combination 7-3 lb MR.tot.73 .

fb .40.or.73 := Z = 22.17-kst Bending stress on brace, Load Combination 7-3 lb fa.40.or.73 fb.40.or.73 IC40.or.LC73 := + - - - - = 0.53 Interaction coefficient for Member 40, Load Fa.LB Fb.LB Combination 7-3 1

MF40.or.LC73 := -IC_ _ _ _ = 1.89 Margin factor for Member 40, Load 40.or.LC73 Combination 7-3

Analysis No. L-002547 Revision No. OA Page 81 7.2. 6 Member 67 I Node 51 7.2.6.1 Determine Current Design Loading Ref. 3a, Section 4.5 and Ref. 3b, Section 6.2.2 identify Member 67 as a critical lower bracing member for the Outer Ring bracing. Loads on the member are identified below. The loads are taken as the maximum from Ref. 3a, Section 4.5, page 6 or Ref. 3b, Section 6.2.2, page 4.

RSSD does not control for SRV loading per Ref. 3a, Section 4.5, page 5.

F a.DL := Okip MR.DL := 0.38ft-kip Axial load and moment due to dead load Fa.Th.146 := 27.40kip MR.Th.146 := 28.90ft-kip Axial load and moment due to thermal load, 146°F Fa.SVSA := 13.7lkip MR.SVSA := 4.52ft, kip Axial load and moment due to SRV-SV~

Fa.LOCA := max(42.12,21.28)*kip + 50.18kip = 92.3-kip Axial load due to LOCA MR.LOCA := max(6.16, 1.97)-ft-kip + 7.64ft-kip = 13.8-ft-kip Moment due to LOCA Fa.DRAG := Okip MR.DRAG:= 3.84ft-kip Axial load and moment due to bracing drag (SVSA or RSSD + Chugging)

F a.Ess := Okip MR.Ess := l.93ft-kip Axial load and moment due to seismic Per Design Input #5, Member 67 was installed out of tolerance, thus additional moment needs to be added for the eccentricity.

elb.6? = 1.06 in Maximum eccentricity of a CBI brace number equivalent to Member 67 (previously specified)

Analysis No. L-002547 Revision No. OA Page 82 7.2.6.2 Evaluate Load Combination 7-1 Fa.Th.212 := IF212*Fa.Th.146 = 51. 24-kip Axial load and moment due to thermal load, prorated for 212°F MR.Th.212 := IF212*MR.Th.146 = 54.04-ft-kip Design axial load on brace, Load Combination 7-1:

Fa.tot.71 := Fa.DL + Fa.Th.212 + Fa.SVSA +Fa.DRAG+ Fa.Ess = 64 ,95-kip Design moment on brace, Load Combination 7-1:

MR.tot.71 := MR.Th.212 +MR.SVSA +MR.DL +MR.DRAG+MR.Ess = 64.71*ft-kip

• - Fa.tot.71 fa.67.or.71 .- A = 3.21-ksi Axial stress on brace, Load Combination 7-1 lb MR.tot.71 + F a.tot.71' elb.67 k .

£b.67.or.71 := Z = 16.97* s1 Bending stress on brace, Load Combination 7-1 lb fa.67.or.71 fb.67.or.71 IC67.or.LC71 := - - - - + - - - - = 0.39 Interaction coefficient for Member 67, Load Fa.LB Pb.LB Combination 7-1 1

MF67

.or.

LC71 *- - - - -

.- IC67.or.LC71

= 2.59 Margin factor for Member 67, Load Combination 7-1

Analysis No. L-002547 Revision No. OA Page 83 7.2.6.3 Evaluate Load Combination 7-2 Fa.Th.190 := IF19o*Fa.Th.146 = 43.29-kip Axial load and moment due to thermal load, prorated for 190°F MR.Th.190 := IF19o*MR.Th.146 = 45.66-ft-kip SRV loads are reduced to 40% of the full load per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-2:

Fa.tot.72 := Fa.DL + Fa.Th.190 + "fSRV.72Fa.SVSA + Fa.LOCA +Fa.DRAG+ Fa.Ess = 141.08-kip Design moment on brace, Load Combination 7-2:

MR.tot.72 := MR.Th.190 + "fSRV.72MR.SVSA + MR.LOCA + MR.DL +MR.DRAG+ MR.Ess = 67.42-ft*kip Fa.tot.72 .

fa.67.or.72 := A = 6.97-kst Axial stress on brace, Load Combination 7-2 lb

~ MR.tot.72 + Fa.tot.72'elb.67 k .

1 b.67.or.72 := Z = 19.24* st Bending stress on brace, Load Combination 7-2 lb f 7 IC *= a.6 .or.72 + fib.67.or.72 = O.SO 67 .or.LC72

• F Interaction coefficient for Member 67, Load a.LB Combination 7-2 MF67.or.LC72 := - - - - = 1.99 Margin factor for Member 67, Load IC67.or.LC72 Combination 7-2

Analysis No. L-002547 Revision No. OA Page 84 7.2.6.4 Evaluate Load Combination 7-3 Fa.Th.150 := IF15o*Fa.Th.146 = 28.84-kip Axial load and moment due to thermal load, prorated for 150°F MR.Th.150 := IF15o*MR.Th.146 = 30.42-ft-kip SRV loads are reduced per Section 6.1.2.1.

Design axial load on brace, Load Combination 7-3:

Fa.tot.73 := Fa.DL + Fa.Th.150 + "YSVSAFa.SVSA + Fa.LOCA +Fa.DRAG + Fa.Ess = 130.74-kip Design moment on brace, Load Combination 7-3:

MR.tot.73 := MR.Th.150 + "YSVSAMR.SVSA + MR.LOCA + MR.DL +MR.DRAG + MR.Ess = 53.54* ft*kip Fa.tot.73 fa.67.or.73 := A = 6.46-ksi Axial stress on brace, Load Combination 7-3 lb MR.tot.73 fb.67.or.73 := Z = 12.89-ksi Bending stress on brace, Load Combination 7-3 lb fa.67.or.73 fb.67 .or.73 IC67.or.LC73 := - - - - + - - - - = 0.37 Interaction coefficient for Member 67, Load Fa.LB Fb.LB Combination 7-3 1

MF67.or.LC73 := - - - - = 2.70 Margin factor for Member 67, Load IC67.or.LC73 Combination 7-3

Analysis No. L-002547 Revision No. OA Page 85 7.3 UPPER DOWNCOMER RING BRACING Existing evaluation of the upper bracing members incorrectly identified that the loads in Calculation 187 (Ref. 3a) govern for LOCA lateral chugging. Review of Calculation 187K (Ref.

3b) shows that the loads in that calculation are governing. Review of the two calculations (Section 4.7 in Cale. 187 and Section 6.4 in Cale. 187K) shows that all loads are the same except for the lateral chugging loads.

7.3.1 Determine Current Design Loading The latest loads in each of these calculations are summarized below to clearly identify the controlling loads. As determine d in Cale. 187 (Ref. 3a) and used in subsequent evaluations in Cale. 187K (Ref. 3b) and L-002547 (Ref. 3c), the LOCA chugging loads bound the other LOCA loads.

The existing evaluations consider a true envelope of the loads for the upper bracing members.

In other words, the maximum force/moment of all upper bracing members for each case are considered to act concurrently. This same conservative approach is cmsidera:I in this evaluation.

All forces and moments due to load cases other than lateral chugging loads:

Axial loads per Section 4.7 of Ref. 3a and Section 6.4 of Ref. 3b:

FA.TH.146 := 32.7kip Axial load due to accident thermal (146 °F)

FA.SRV.SVSA := 7-74 kip Axial load due to SRV SVSA load load FA.CHUG.DRAG:= 12.I0kip Axial load due to chugging drag load FA.SRV.SPPT := 60.65kip Axial load due to SRV support load Minor axis bending moments per Section 4.7 of Ref. 3a and Section 6.4 of Ref. 3b:

MB.TH.146 := ?.3kip*ft Minor axis bending due to accident thermal (146 °F)

MB.SRV.SVSA := 5.07kip-ft Minor axis bending due to SRV SVSA load MB.CHUG.DRAG:= 7.14kip*ft Minor axis bending due to chugging drag MB.SEIS := 2.74kip*ft Minor axis bending due to seismic MB.SRV.SPPT := 62.46kip*ft Minor axis bending due to SRV support load

Analysis No. L-002547 Revision No. OA Page 86 Major axis bending momen ts per Section 4.7 of Ref. 3a and Section 6.4 of Ref. 3b:

Mc.TH.146 := 70.8kip*ft Major axis bending due to accident thermal (146 °F)

Mc.SRV.SVSA := 38.45kip* ft Major axis bending due to SRV SVSA load Mc.CHUG.DRAG:= 64.21kip-ft Major axis bending due to chugging drag Mc.SEIS := 2.88kip* ft Major axis bending due to seismic Mc.DEAD := 0.38kip* ft Major axis bending due to dead load Mc.SNUB:= 97.94kip*ft Major axis bending due to snubbe r suppor t load Mc.SRV.SPPT := 99 .?0kip-ft Major axis bending due to SRV support load Forces and momen ts due to lateral chugging loads:

Calculation 187 loads (Section 4.7 of Ref. 3a):

FA.CHUG.LAT.187 := 3.14kip Axial load due to lateral chugging MB.CHUG.LAT.187 := 3.Skip-ft Minor axis bending due to lateral chuggin g Mc.CHUG.LAT.187 := 2S,Okip*ft Major axis bending due to lateral chuggin g Calculation 187K loads (Section 6.4 of Ref. 3b):

FA.CHUG.LAT.187K := 16.62kip Axial load due to lateral chugging MB.CHUG.LAT.187K := 13.265kip*ft Minor axis bending due to lateral chuggin g Mc.CHUG.LAT.187K := 55.628kip*ft Major axis bending due to lateral chuggin g

Analysis No. L-002547 Revision No. OA Page 87 Governing lateral chugging forces and moments:

FA.CHlJG.LAT.187KJJ FA.CHUG.LAT:= max F = 16.62-kip Governing axial load due to

((

A.CHUG.LAT.187 lateral chugging MB.CHUG.LAT. l 87KJ)

Ma.CHUG.LAT:= max M

(( = 13.27-kip*ft Governing minor axis bending B.CHUG.LAT.187 due to lateral chugging Mc.CHUG.LAT.187KJ1J Mc.CHUG.LAT:= max = 55.63-kip*ft Governing major axis bending

~( Mc.CHUG.LAT.187 due to lateral chugging 7.3.2 Evaluate Braces The upper bracing is evaluated for a 212°F accident temperature. This accident temperature along with no reduction in SRV loading is used to conservatively bound all LOCA cases prOJided in Table 6.1-1. Per Table 6.1-1, the maximum temperature for the plant conditions in which both LOCA and SRV occur is 190°F. Therefore, considering the 212°F accident temperature simultaneously with both SRV and LOCA loads is conservative. In addition, the 60% reduction in SRV loading at temperatures equal to or greater than 190°F is conservatively not considered to bound the 150°F LOCA cases.

212'FAccident Temperature Additional load due to thermal increase for 105% power uprate. Only the thermal loads are increased.

IF212 = 1.87 Increase factor on thermal loads for increase to 212°F accident temperature Design axial load on brace, 212°F temperature case:

FA.212 := IF212*FA.TH.146 *** = 158.26-kip

+ (FA.SRV.SVSA + FA.SRV.SPPT) +(FA.CHUG.DRAG+ FA.CHUG.LAT)

Design minor axis moment on brace, 212°F temperature case:

Me.212 := IF212*Me.TH.146 + Me.SEIS ... = 104.33-ft-kip

+ (Me.SRV.SVSA + Me.SRV.SPPT) +(Ma.CHUG .DRAG+ Me.CHUG.LAT)

Analysis No. L-002547 Revision No. OA Page 88 Design major axis moment on brace, 212°F temperature case:

Mc.212 := IF212*Mc.TH.146 +Mc.DEA D+ Mc.SEIS +Mc.SNU B*** = 491.58-ft-kip

+ (Mc.SRV. SVSA + Mc.SRV.SPPT) + (Mc.cmJG .DRAG + Mc.CHUG.LAT)

FA.212 .

fA.212 := - - - = 4.42-kst At.uh Axial stress on brace, 212°F temperatu re case MB.212 .

fB.212 := - - -

8 y.uh

= 23 .79-kst Minor axis bending stress on brace, 212°F temperatu re case Mc.212 .

fc.2 12 := - - - = 20.03-ksi 8 x.uh Major axis bending stress on brace, 212°F temperatu re case fA.212 fa.212 fc.212 ICUB.212 := - - + - - + - - = 0.92 Interaction coefficient for Upper Bracing, Fa.UB Fh.UB Fh.UB 212°F temperatu re case 1

MFUB.212 := - - - = 1.08 Margin factor for Upper Bracing, 212°F ICUB.212 temperatu re case

Analysis No. L-002547 Revision No. OA Page 89 7.4 LOWER DOWNCOMER BRACING GUSSET PLATE SECTION Consistent with Cale. L-002547 (Ref. 3c), it is considered that the critic.al members determine d

in Cale. 187 (Ref. 3a) and in Cale. 187K (Ref. 3b), remain bounding when thermal loads are increased.

Cale. 187K determine d that different members controlled when the revised lateral chugging loads are considered. Review of the loads for the inner and outer ring critic.al gusset plate evaluation s

in Cale. 187 Section 2.8.2 (Ref. 3a) and Cale. 187K Section 6.3 (Ref. 3b) shows that the loads for the inner ring gusset plate evaluation in Cale. 187K are governing (Member 145 / Node 108).

In addition, the inner ring loads from Cale. 187K have larger thermal moments which will be more greatly affected by the 105% power uprate.

Therefore, the gusset plate evaluation considers the loading from the inner ring evaluation (Member 145 / Node 108) in Cale. 187K Section 6.3 (Ref. 3b).

7.4. 1 Determine Current Design Loading Axial forces and moments for inner ring (Member 145 / Node 108) per Cale. 187K (Section 6.3 of Ref. 3b) unless otherwise noted:

FA.Th.146.gp := 21.84-kip Axial load due to thermal

-13610) "Node 112")

MTh.146.gp := ( 24931 ft-lbf ( "Node 108" Moment at each end of member due to thermal load, 146°F (Ref. 3e, PIPSYS Run 374PCG, Section D, page 1-13)

FA.chug.lat.gp := 61.14-kip Axial load due to lateral chugging Mchug.lat.gp := 21.36

• kip* ft Moment due to lateral chugging FA.chug.drag.gp := 13.69* kip Axial load due to chugging drag Mchug.drag.gp := 17 .58 *kip* ft Moment due to chugging drag FA.RSSD.gp := 10.05 *kip Axial load due to SRV-RSSD MRSSD.gp := 9.24-kip*ft Moment due to SRV-RSSD FA.SVSA.gp := 8.98-kip Axial load due to SRV-SVSA MsvSA.gp := 3.69-kip*ft Moment due to SRV-SVSA

Analysis No. L-002547 Revision No. OA Page 90 By inspection RSSD loads control over SVSA loads.

FA.RSSD.DRAG.gp := 2.85-kip Axial load due to SRV-RSSD drag MRSSD.DRAG.gp := 2.66-kip*ft Moment due to SRV-RSSD drag The controlling inner ring loads per Cale. 187K (Ref. 3b) are evaluated using the same three (3) load combinations considered for the lower bracing members as outlined in Section 6.1.2.1.

Due to the shape of the cross section, the horizontal (Ma) or vertical (Mc) moments will result in the largest stress at the extreme fibers, not the resultant of the two. The section has the same bending capacity in each direction, so the governing moment between the horizontal and vertical directions is considered. Review of Section 6.3 of Cale. 187K (Ref. 3b) shows that the governing moment for Member 145 corresponds to the total vertical moment (Mc). The horizontal moments (Ma) are substantially smaller. Review of the as-built eccentricities in Section 3.4 of Cale. 187 (Ref. 3a) shows that all CBI brace members represented by PIPSYS model member 145 only have horizontal as-built eccentricities. The largest of which is 0.82 inches. Therefore, the as-built eccentricities corresponding to member 145 will not increase the critical vertical moment on the gusset section. The horizontal eccentricity will not result in the horizontal moment governing based on comparison of the horizontal and vertical moments.

The thermal moment for the brace can be reduced by considering the actual length of the member since the PIPSYS analysis output is given at the working points of the analytical members (not the actual member ends) and the thermal moment gradient along the length of the member is known.

~A j~~~?!:*I"'

I t ~ **:,..,

-Vt*,..

. . 4' . ,:: ':9** :*

C\I *~"'

cri .

'in

'18 II.

IOS Figure 7.4.1-1: Member 145 Location in PIPSYS Model (Ref. 3a, Section 2.1, page 2)

Analysis No. L-002547 Revision No. OA Page 91 Figure 7 .4.1-2: Member 145 Location in Installed Configuration (Ref. 2a)

The node-to-nod e length of this member is determined based on the measurements in Ref. 2a.

r1 := 14ft + I I.Sin r 2 := ( 19ft + 9in) + (3ft + 6in) = 23.25* ft Radius to downcomer or pedestal X- and Y-coordinates of the downcomer/wall embed to which Member 67 attaches:

-r 1* cos(346deg - 270deg)) (-3 .62) *- (r 1*sin(346deg - 270deg) ) - ( 14.51) xo *= = .ft Yoe*- - .ft C * ( -r2 -cos(342deg - 270deg) -7.18 r2* sin(342deg - 270deg) 22.11 Node-to-node length of Member 67 24in Lcrit := Lnn - = 7.39 -ft Length to critical section of Member 67, at outer face of down comer

Analysis No. L-002547 Revision No. OA Page 92 Calculate seismic SSE moment in brace:

Note that the existing gusset evaluations do not consider dead load or seismic load as they are deemed to be insignificant. Review of all other brace evaluations shows the dead loads are extremely small and will be negligible. However, because there is very little margin in the members, the small but not negligible seismic moments could impact the evaluation and should be included. The seismic moment is calculated following the methodolog y presented in Section 2.4 of Cale. 187 (Ref. 3a) and used in Section 2.5 of Cale. 187. Per Section 2.4 of Cale. 187, the Mc seismic moment for the inner ring is larger and therefore considered here. This approach distributes a portion of the total seismic moment to the brace based on the stiffness of the brace relative to that of the downcomer. Note that this approach uses the full section (no reduction for corrosion) which is acceptable since the full section is considered for the downcomer, as well.

Mc.seis := 8.07lkip-ft Controlling inner ring seismic SSE moment per Section 2.4 of Cale. 187 (Ref. 3a)

Ibrace := 162in4 Moment of inertia for full brace section per Section 2.4 of Cale. 187 (Ref. 3a)

Moment of inertia for full downcomer section per Section 2.4 of Cale. 187 (Ref. 3a)

Ldown := 23.92ft Length of downcomer considered in distribution of seismic moment per Section 2.4 of Cale. 187 (Ref. 3a)

-1 1brace 1brace 1down .

MsEIS.gp := Mc.seis* - - - -

( Lnn ) ( Lnn + - -) = 1.51-ktp*ft Seismic in brace gusset plate Ldown Since the thermal moment gradient is known, pro-rate to find the thermal moment components at the face of the down comer.

Mrh.146.gp := linterpll(Lonn) ,Mrh.i 46 .gp ,Leri~ = 20.34-ft-kip Moment due to thermal load at

~ ~ 146°F, linearly pro-rated to determine moment at face of down comer

Analysis No. L-002547 Revision No. OA Page 93 7.4.2 Evaluate Load Combination 7-1 FA.Th.212.gp := IF212*(F A.Th.146.gp) = 40.84-kip Axial load and moment due to thermal load, prorated for 212°F MTh.212.gp := IF212*(MTh.146.gp) = 38.03-ft*kip Design axial load on gusset section, Load Combination 7-1:

Fa.tot.gp.71 := FA.Th.212.gp + FA.RSSD.gp + FA.RSSD.DRAG.gp = 53.74-kip Design moment on gusset section, Load Combination 7-1:

MR.tot.gp.71 := MRSSD.DRAG.gp + MsEIS.gp + MTh.212.gp + MRSSD.gp = 51.45-ft*kip Fa.tot.gp.71 MR.tot.gp.71

---

+----

Agp Zgp ICgp.71 := _ _;;;.;__ _ ____,;=-- = 0.45 Interaction ooefficient for normal stress in Fba.gp gusset plate 1

MFgp.71 := IC = 2.21 Margin factor for normal stress in gusset gp.71 plate

Analysis No. L-002547 Revision No. OA Page 94 7.4.3 Evaluate Load Combination 7-2 FA.Th.190.gp := IF19o*(F A.Th.146.gp) = 34.51-kip Axial load and moment due to thermal load, prorated for 190°F MTh.190.gp := IF19o*(MTh.146.gp) = 32.14-ft-kip SRV loads are reduced to 40% of the full load per Section 6.1.2.1.

Design axial load on gusset section, Load Combination 7-2:

Fa.tot.gp.72 := F A.Th.190.gp + "fSRV.n*FA.RSSD.gp + F A.chug.lat.gp *** = 116.21 -kip

+ FA.chug.drag.gp + FA.RSSD.DRAG.gp Design moment on gusset section, Load Combination 7-2:

hltot.gp.72 := MRSSD.DRAG.gp + MsEIS.gp + MTh.190.gp ... = 78.94-ft-kip

+ ("fSRV.72" MRSSD.gp ... )

+ hlchug.lat.gp + Mchug.drag.gp Fa.tot.gp.7-

---

2 +_ M°tot.gp.72 Agp Zgp ICgp.72 := - _ _ : ~ - - - ~ - = 0.73 Interaction coefficient for normal stress in Fba.gp gusset plate 1

MFgp.72 := - - = 1.37 Margin factor for normal stress in gusset ICgp.72 plate

Analysis No. L-002547 Revision No. OA Page 95 7.4.4 Evaluate Load Combination 7-3 FA.Th.150.gp := IF15o*(FA.Th.146.gp) = 22.99-kip Axial load and moment due to thermal load, prorated for 150°F MTh.150.gp := IF15o*(MTh. l46.gp) = 2 1.41-ft*kip SRV RSSD loads are reduced by 20% per Section 6.1.2.1.

Design axial load on gusset section, Load Combination 7-3:

Fa.tot.gp.73 := FA.Th.150.gp + 'YRSSD'FA.RSSD.gp + FA.chug.Iat.gp ... = 108.71-kip

+ FA.chug.drag.gp + FA.RSSD.DRAG.gp Design moment on gusset section, Load Combination 7-3:

MR.tot.gp.73 := MRSSD.DRAG.gp + MsEIS.gp + MTh.150.gp ... = 71.91 *ft*kip

+ ('YRSSD' MRSSD.gp *** )

+ Mchug.lat.gp + Mchug.drag.gp F a.tot.gp. 73 MR.tot.gp.73

---

+----

Agp Zgp ICgp.73 := _ _;;;.;;...._ _ ___,;;;.:___ = 0.67 Interaction roefficient for normal stress in Fba.gp gusset plate 1

MFgp.73 := = 1.50 Margin factor for normal stress in gusset ICgp.73 plate

Analysis No. L-002547 Revision No. OA Page 96 8.0 RESULTS & CONCLUSIONS 8.1 RESULTS Results are tabulated in the sections that follow.

8.1.1 Lower Downcomer Bracing, Inner Ring IC126.ir.LC71 MF126.ir.LC71 IC l 26.ir.LC72 MF 126.ir.LC72 0.80 1.25 IC l 26.ir.LC73 MF 126.ir.LC73 0.97 1.03 IC75.ir.LC71 0.81 MF75.ir.LC71 1.24 IC75.ir.LC72 0.70 MF75.ir.LC72 1.43 IC75.ir.LC73 0.90 1.11 MF75.ir.LC73 0.80 1.25 IC86.ir.LC71 MF86.ir.LC7 l 0.80 1.26 IC86.ir.LC72 MF86.ir.LC72 0.99 1.01 IC86.ir.LC73 0.73 MF86.ir.LC73 1.38 IC:= = 0.20 MF:= =

IC7.ir.LC71 MF7.ir.LC71 5.09 0.42 2.36 IC7.ir.LC72 MF7.ir.LC72 0.46 2.19 IC7.ir.LC73 MF7.ir.LC73 0.37 2.70 ICs7.ir.LC71 0.66 MFs7.ir.LC71 1.51 ICs7.ir.LC 72 0.68 MFs7.ir.LC72 1.48 ICs7.ir.LC 73 0.28 3.63 MF 57 .ir.LC73 0.61 1.63 IC47.ir.LC71 MF47.ir.LC71 0.60 1.68 IC47.ir.LC72 MF47.ir.LC72 IC47.ir.LC73 MF47.ir.LC73

Analysis No. L-002547 Revision No. OA Page 97 Table 8.1.1-1: Summary of Results for Lower Downcomer Bracing, Inner Ring Interaction Margin Member/Node and Load Combination Coefficient Factor 126/94, LC 7-1 (212°F Temperature, SBO) 0.80 1.25 126/94, LC 7-2 (190°F Temperature, IBA) 0.97 1.03 126/94 LC 7-3 (150°F Temperature IBA/SBA) 0.81 1.24 75/49, LC 7-1 (212°F Temperature SBO) 0.70 1.43 75/49, LC 7-2 (190°F Temperature, IBA) 0.90 1.11 75/49 LC 7-3 (150°F Temperature, IBA/SBA) 0.80 1.25 86/63 LC 7-1 (212°F Temoerature SBO) 0.80 1.26 86/63, LC 7-2 (190°F Temperature IBA) 0.99 1.01 86/63 LC 7-3 (150°F Temperature IBA/SBA) 0.73 1.38 7/11 LC 7-1 (212°F Temperature, SBO) 0.20 5.09 7/11 LC 7-2 (190°F Temoerature IBA) 0.42 2.36 7/11 LC 7-3 (150°F Temperature IBA/SBA) 0.46 2.19 57/49 LC 7-1 (212°F Temperature SBO) 0.37 2.70 57/49 LC 7-2 (190°F Temperature, IBA) 0.66 1.51 57/49 LC 7-3 (150°F Temperature IBA/SBA) 0.68 1.48 47/35 LC 7-1 (212°F Temperature S8O) 0.28 3.63 47/35, LC 7-2 (190°F Temperature, IBA) 0.61 1.63 47/35 LC 7-3 (150°F Temperature IBA/SBA) 0.60 1.68

Analysis No. L-002547 Revision No. OA Page 98 8.1.2 Lower Downcomer Bracing, Outer Ring IC126.or.LC71 MF126.or.LC71 IC126.or.LC72 MF126.or.LC72 0.69 1.45 ICt26.or.LC7 3 MF l 26.or.LC73 0.75 1.33 IC41.or.LC71 0.60 MF41,or.LC71 1.66 IC41,or.LC72 0.72 MF4 l .or.LC72 1.40 0.83 1.20 IC41.or.LC73 MF4 l .or.LC73 0.65 1.54 IC10I.or.LC71 MF 10 l.or.LC7 l 0.27 3.65 ICtOI.or.LC 72 MF101.or.LC72 0.52 1.93 IC 10 l.or.LC73 0.53 MF IO l .or.LC73 1.87 IC:= = MF*-.- =

IC104.or.LC71 0.26 3.92 MF I 04.or.LC7 l 0.42 2.41 IC104.or.LC72 MF 104.or.LC72 0.39 2.58 IC104.or.LC73 MF 104.or.LC73 0.34 2.91 IC40,or.LC71 0.53 MF40.or.LC71 1.87 IC40,or.LC72 0.53 MF40.or.LC72 1.89 IC40.or.LC73 0.39 2.59 MF40.or.LC73 0.50 1.99 IC67 .or.LC7 l MF67.or.LC71 0.37 2.70 IC67.or.LC72 MF67.or.LC 72 IC67.or.LC73 MF67.or.LC73

Analysis No. L-002547 Revision No. OA Page 99 Table 8.1.2-1: Summary of Results for Lower Downcomer Bracing, Outer Ring Interaction Margin Member/Node and Load Combination Coefficient Factor 126/100, LC 7-1 (212°F Temperature, SBO) 0.69 1.45 126/100, LC 7-2 (190°F Temperature, IBA) 0.75 1.33 126/100 LC 7-3 (150°F Temperature IBA/SBA) 0.60 1.66 41/31 LC 7-1 (212°F Temperature SBO) 0.72 1.40 41/31 LC 7-2 (190°F Temcerature, IBA) 0.83 1.20 41/31 LC 7-3 (150°F Temoerature IBA/SBA) 0.65 1.54 101/73 LC 7-1 (212°F Temperature SBO) 0.27 3.65 101/73, LC 7-2 (190°F Temperature, IBA) 0.52 1.93 101/73 LC 7-3 (150°F Temperature IBA/SBA) 0.53 1.87 104/100, LC 7-1 (212°F Temperature, SBO) 0.26 3.92 104/100 LC 7-2 (190°F Temcerature IBA) 0.42 2.41 104/100 LC 7-3 (150°F Temperature IBA/SBA) 0.39 2.58 40/22 LC 7-1 (212°F Temperature SBO) 0.34 2.91 40/22, LC 7-2 (190°F Temperature IBA) 0.53 1.87 40/22 LC 7-3 (150°F Temperature IBA/SBA) 0.53 1.89 67/51 LC 7-1 (212°F Temperature SBO) 0.39 2.59 67/51, LC 7-2 (190°F Temperature, IBA} 0.50 1.99 67/51 LC 7-3 (150°F Temperature IBA/SBA} 0.37 2.70 8.1.3 Upper Downcomer Bracing ICUB.212 = 0.92 MFUB.212 = I.OS IC and margin factor for Upper Bracing, LC 7-1, IBA case, conservatively using 212°F temperature instead of 190°F

8. 1.4 Lower Downcomer Bracing Gusset Plate Section 1Cgp_ 71 = 0.45 MFgp.71 = 2.21 IC and margin factor for Lower Bracing Gusset Plate Section, LC 7-1, SBO case with 212°F accident temperature ICgp.72 = 0.73 MFgp.72 = 1.37 IC and margin factor for Lower Bracing Gusset Plate Section, LC 7-2, IBA case with 190°F accident temperature ICgp.73 = 0.67 MFgp.7 3 = 1.50 IC and margin factor for Lower Bracing Gusset Plate Section, LC 7-3, IBA/SBA case with 150°F accident temperature

Analysis No. L-002547 Revision No. 0A Page 100

8.2 CONCLUSION

S The purpose of this minor revision is to provide a bounding evaluation for the upper and lower downcomer brace members and lower downcomer brace gusset plate section used at some oonnections to the downcomers. The refined analysis considering the correct bounding loads and using the elastic section modulus determined the stresses exceed the DB allowables for the lower downcomer braces and the gusset plate section. Therefore, a LAR is prepared via Licensing Action Ll-21-0215 to allow for the use of plastic section modulus for these. The upper downcomer bracing members are evaluated using elastic section properties, oonsistent with the current licensing basis.

As shown herein, the critical downoomer brace members and the gusset plate section are acceptable for the design loading.