ML20112C020
| ML20112C020 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 05/21/1996 |
| From: | Bowman M, Doroshuk B, Tucker R BALTIMORE GAS & ELECTRIC CO. |
| To: | |
| Shared Package | |
| ML20112B955 | List: |
| References | |
| NUDOCS 9605240123 | |
| Download: ML20112C020 (100) | |
Text
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Calvert Chffs NuclearPowerPlant i 1
License RenewalProject I
Aging Management Review Report !
for the i
Auxiliary Building l O Revision 2 May, 1996 Prepared by: !-/Et ML 71 as c Date: / (
"#"#~
R.L. Tucker i
Reviewed by: Me % ~ Date: {/ J '/P4
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M.E. Bowman Approved by: Date: 5 2t B[ W. Doroshuk O
9605240123 960522 PDR ADOCK 05000317 P PDR
l c LIFE CYCLE MANAGEMENT UNIT FINAL REPORT AUXILIARY BUILDING AGING MANAGEMENT REVIEW TABLE OF CONTENTS i l
SECTION PAGE NUMBER l TABLE OF CONTENTS i l
LIST OF ATTACHMENTS iii LIST OF APPENDICES tv j l
l LIST OFTABLES V LIST OF EFFECTIVE PAGES vi
1.0 INTRODUCTION
1-1 i
1.1 Auxiliary Building Description 1-1 !
1.1.1 Auxiliary Building LCM Description 1-1 1.1.2 Auxiliary Building LCM Boundary 1-1 1
1.1.3 Auxiliary Building Intended Functions 1-2 1.2 Evaluation Methods 1-3 !
1.3 Auxiliary Building Specific Definitions 1-3 l 1.4 Auxiliary Building Specific References 1-3
, 2.0 STRUCTURAL COMPONENTS WFITIIN THE SCOPE OF !
- LICENSE RENEWAL 2-1 ;
l 3.0 STRUCTURAL COMPONENTS PRE-EVALUATION 3-1 l
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AUXILIARY BUILDING i REVISION 2
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FINAL REPORT AUXILIARY BUILDING AGING MANAGEMENT REVIEW l TABLE OF CONTENTS i SECTION PAGE NUMBER ]
4.0 STRUCTURAL COMPONENTS AGING EITECTS EVALUATION 4-1
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4.1 Evaluation 4-1 4.2 Aging Mechanisms 4-1 j l
4.2.1 Potential Aging Mechanisms 4-1 4.2.2 Component Grouping 4-2 l 4.2.3 Plausible Aging Mechamsms 4-3 1
4.2.4 Aging Management Program Identification 4-3
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l 4.2.5 Aging Management Recommendations 4-4 !
l v 5.0 PROGRAM EVALUATION 5-1 5.1 Program Adequacy Evaluation 5-1 l
5.2 Structural Components Subject to Adequate Programs 5-1 '
5.2.1 Existing Programs 5-1 ,
l 5.2.2 Modified Existing Programs 5-2 5.2.3 New Programs 5-2 l
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Attaclunent1 Potential Aging Mechanisms Applicable to Structural Components l Attachment 2 Plausible Aging Mechanisms Applicable to Structural Components l
Attachment 3 Structural Component - Aging Mechanism Matrix Codes l
Attachment 4 Summary of Aging Management Review Results Attachment 5 Adequate Program Evaluation Attachment 6 NOT USED l
Attachment 7 Walkdown Report - CCNPP Auxiliary Building, November 1994 Attachment 8 Attributes in New Program F'N U
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i LIST OF APPENDICES
! l Appendix A Freeze-Thaw Appendix B Leaching of Calcium Hydroxide l Appendix C Aggressive Chemicals l l
Appendix D Reaction with Aggregates Appendix E Corrosionin Embedded Steel /Rebar
- Appendix F Creep Appendix G Shrinkage l Appendix H Abrasion and Cavitation l Appendix I Cracking of Masonry Block Walls f} AppenLi Settlement
!%J j Appendix K Corrosion of Steel Appendix L Corrosionof Liner Appendix M Corrosion of Tendons Appendix N Prestress Losses l
l l Appendix 0 Weathering Appendix R Elevated Temperature Appendix S Irradiation Appendix T Fatigue l
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LIFE CYCLE MANAGEMENT UNIT AUXILIARY BUILDING AGING MANAGEMENT REVIEW LIST OFTABLES Table Title Page Number 1-1 Auxiliary Building Specific References 1-4 2-1 Auxiliary Building Structural Components Within the Scope of License Renewal 2-2 ;
4-1 List of Potential Aging Mechamsms for Auxiliary Building Structural Components 4-6 I
4-2 Auxiliary Building Aging Effects i Evaluation Summary 4-7 i
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O AGING MANAGEMENT REVIEW RESUL15 FINAL REPORT AUXILIARY BUILDING v REVISION 2
l LIFE CYCLE MANAGEMENT UNIT FINAL REPORT AUXILIARY BUILDING AGING MANAGEMENT REVIEW ;
1 i l LIST OF EFFECTIVE PAGES I l
Revision Pages Summary of Change 0 All Initial revision prepared using LCM-10S, Revision 1.
1 All Changes made to reflect disposition of Technical Problem Reports !
written against Revision 0 and to correct transcription errors between I the results and the final report sections.
2 All Wording changes to make the language in the final report sections :
more consistent with the language used in the Integrated Plant Assessment Methodology. Also, technical changes regarding the aging management strategy used to address degradation effects associated with corrosionin structural steel.
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1.0 INTRODUCTION
1.1 AUXILIARY BUILDING DESCRII'rION This section describes the scope and boundaries of the Auxdiary Building as it was evaluated. Section 1.1.1 provides a brief synopsis of the Auxiliary Building as described in existing plant documentation. The Auxdiary Building boundary is defined in Section 1.1.2 to clarify the portions of the structure considered in this :
evaluation. Section 1.1.3 is a detailed breakdown of the Auxdiary Building intended functions for license renewal and is provided as a basis for component scoping and the identification of component-specific functions.
1.1.1 Auxiliary Building LCM Description The Auxiliary Building is a Class 1 structure, located between the Unit-1 and Unit-2 Containment Class 1 structures and adjacent to the Turbine Building. The Auxdiary Building is pnmarily a reinforced concrete structure with a mat foundation that supports a structural steel and reinforced concrete frame which consists mainly of reinforced concrete O
walls and floors. On the top of the structure, over the fuel handling area, is d a secondary steel frame structure with missile resistant concrete walls and roof, which houses the Spent Fuel Cask Handling Crane.
1.1.2 Auxiliary Building LCM Boundary I The Auxiliary Building structure and its structural components provide support and shelter to safety related and non-safety related equipment inside the Auxdiary Building. The LCM boundary addressed by this scoping and evaluation included all in-Auxiliary Building structural components serving such functions but did not include commodity items such as pipe support and snubbers. Structural components within the Auxiliary Building include supports for the following major device types:
Accumulators (ACCUMU), compressors (COMP), fans (FAN), heat exchangers (HX), motors (MOTOR), motor control centers (MCC), pumps (PUMP), emergency diesels (GEN), demineralizer (DEMIN), tanks (VESSEL).
Also included in the Auxiliary Building boundary are structural or functional supports for non-safety related equipment of the above device types. During an abnormal event such as a seismic event, failure of these l- AGING MANAGEMENT REVIEW RESULTS FINAL REPORT AUXILIARY BUILDING 1-1 REVISION 2 l . - -
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non-safety-related equipment supports must not adversely affect the operability of other safety related components.
1.13 Auxiliary Building Intended Functions A detailed review of the Auxihary Building intended functions was completed during the scoping process described in the BGE Integrated Plant Assessment Methodology. The following functions for the Auxthary Building were identified as structural intended functions on Table IS of
" Component Level Scoping Results for the Auxiliary Building."
1.13.1 Function LR-S-1 Provides structural and/or functional support, or both, to safety-related equipment.
1.13.2 Function LR-S-2 3
[d Provides shelter / protection to safety-related equipment (Including HELB and Radiation Protection).
1.133 Function LR-S-3 Serves as a pressure boundary or fission product retention barrier to protect public health and safety in the event of any postulated DBEs.
1.13.4 Function LR-S-4 Serves as a missile barrier (internal or external).
1.13.5 Function LR-S-5 Provides structural and/or functional support to non-safety-related equipment whose failure could directly prevent satisfactory accomplishment of any of the intended safety-related functions.
1.13.6 Function LR-S-6 Provides flood protective barrier (internal flooding event).
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1.1.3.7 Function LR-S Provides rated fire barriers to confine or retard a fire from spreading to or from adjacent areas of the plant.
l 1.2 EVALUATION METHODS Auxiliary Building structural components within the scope of license renewal were l evaluated in accordance with BGE procedure EN-1-3051, Revision 0, " Component Aging Management Review Procedure for Structures." The results of these evaluations are I summarized in Sections 3.0 through 5.0.
1.3 AUXILIARY BUILDING SPECIFIC DEFINITIONS This section provides the definitions for any specific terms unique to the Auxiliary Building structural component level evaluation.
Term Definition l m None N/A 1.4 AUXILIARY BUILDING SPECIFIC REFERENCES Refennces utilized in the completion of the Auxiliary Building structural component level i evaluation cee listed in Table 1-1. Drawings and procedures used as source documents in
! the evaluation were taken at the revision level of record at the start of this task which was October 1994. The updates performed in Revisions 1 and 2 of this report incorporated several TPRs. The update performed in Revision 2 was performed to address a new strategy in the aging management of corrosion effects on structural steel. Only references affected by the Revision 1 and Revision 2 updates were revised.
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Revision 0 and Revision I were done to LCM-10S. EN-1-305 is new version of LCM-10S which updated procedure format and terminology only.
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Table 1-1 l Auxiliary Building Specific References j l
l Document ID. Document Title Revision No. Date Type Uf5AR Calvert Cliffs Nuclear Power Plant Units 1 and 2, Updated Final 16 1994 Report l Safety Analysis Report 1 1
l Technical Calvert Chffs Nuclear Power Plant, Units 1 aM 2. Technical 182 9/ 93 Report Specification Specification 159 9/ 93
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Component level Scoping Results for the Auxiliary Building 1 1996 Report EPRI RP-2643-27 Class I Structures License Renewal Industry Report -
12/ 91 Report 1
Component Evaluation and Program Evaluation Results for 2 1996 Report Containment System No.59
- Mather, D., "How to Make Concate that will be immune to the -
11/89 Paper l effects of freezing and thawing," ACI Fall Convention, San l Diego 1
Troxell, G.E., Davis, H.E., and Kelly, J.W., " Composition and 2*8 Edition 1968 Text Properties of Concrete," McGraw Hill ASTM C33-82 " Standard Specification for Concrete Aggregates," American - 1982 Spec Society of Testing and Materials Civil and Structural Design Criteria for Calvert Cliffs Nuclear 0 8/ 91 Guide Power Plant Unit No.1 and 2, by fkchtel Power Corp.
(v/
6750C9 Specification for Furrushing and Delivery of Concrete - Calvert 8 4/70 Spec Chffs Nuclear Power Plant Unit No.1 and 2 l ACI 318-63 " Building Code Requirements for Reinforced Concrete," - 1963 Code l American Concrete Institute ACI 201.2R-67 " Guide to Durable Concrete," American Concrete Institute -
1%7 Standard
" Concrete Manual," U.S. Department of the Interior 88' Edition 1975 Code 6750C23E Specification for Funushing and Installation of Piezometer - 0 11/73 Spec Calvert Cliffs Nuclear Power Plant Unit No.1 and 2 ASTM C-289-66 " Potential Reactivity of Aggregates (Chemical Method}," -
1966 Code American Society of Testing and Materials 1
ASTM C-295-65 " Petrographic Examination of Aggmgates for Concrete," -
1965 Code American Society of Testing and Materials letter from Charles County Sand & Gravel Co. to Bechtel Corp. -
6/ 72 letter Skoulikidas,T.,Tsakopoulos, A.,and Moropoulos,T., - -
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" Accelerated Rebar Corrosion When Connected to Lightning Conductors and Protection of Rebars with Needles Diodes Using Atmospheric Electncity,"in Publication ASTM STP 906,
" Corrosion Effects of Stray Currents and the Techniques for '
Evaluating Corrosion of Rebars in Concrete" ACI-209R-82 " Prediction of Creep, Shrinlunge, and Tempw ature Effects in - 1982 Standard ConcreteStructures," AmericanConcreteInstitute t
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Table 1-1 Auxiliary Building Specific References Byument ID. Document Title Revision No. Dat,e Type
- " Design and Control of Concrete Mixturts," Portland Cement 11* Edition 7/68 Guide Association IAEA-TECDOC- " Pilot Studies on Management of Aging of Nuclear Power Plant -
10/92 Report 670 Components," International Atomic Energy Agency MN-3-100 Painting and Other Protective Coatings 0 9/94 Procedure TRD-A-1000 Coating Application Performance Standard 8 8/ 91 Spec 6750-A-24 Specification for Painting and Special Coatings 12 10/82 Spec 6750 C-31 Specification for Furnishing, Detailing, Painting, and Delivering 2 5/70 Spec Containment and Auxiliary Buildmg StructuralSteel ACI 215R-74 " Consideration for Design of Concrete Structures Suljected to - 1986 Standard Fatigue loading," Amencan Concrete Institute
" Specification for the Desigrt Fabrication, and Erection of -
1963 Spec Structural Steel for Buildings," American Institute of Steel Construction Brockengrough, R.L, and Johnson, B.G., " Steel Design Manual," -
5/ 74 Text A United States SteelCorporation 6750-C-28 Specification for Stainless Steel liner Plate and Spent Fuel Pool 5 6/73 Spec Bulkhead Gate NUREC/CR4652, Naus, D.J.," Concrete Component Aging and its Significance -
9/86 Paper ORNL/TM-10059 Relative to Life Extension of Nuclear Power Plants," Oak Ridge National Laboratory, Oak Ridge, TN ACI 34945 " Code Requtrements for Nuclear Safety Related Concrete - 1985 Code Structures," AmericanConcreteinstitute EQ Design Manual, Calvert Chffs Nuclear Power Plant 17 1992 Guide 6750-A-2 Specification for Funushmg, Delivery and Erection of the 1 9/70 Spec Budding Masonry ,
1 ASME Section!!!, " Code for Concrete Reactor Vessels and Containments," - 1986 Code 4 Division 2 l American Society of Mechanical Engineers Boiler and Pressure Vessel Code 62-149-E Appendix "R" Separation Requirements, Aux. Bldg. and Ctmt. 5 10/93 Drawing Sruct., Elevations (-)10-0" and (-)15'-0" 62-150-E Appendix "R" Scparation Requirements Aux. Bldg. and Ctmt. 6 5/ 94 Drawing Sruct., Elevations 5'#
62-151-E Appendix "R" Separation Requirements, Aux. Bldg. and Ctmt. 6 5/94 Drawing Sruct., Elevations 27'-0" 62-152-E Appendix "R" Separation Requirements, Aux. Bldg. and Ctmt. 7 5/94 Drawing Sruct., Devations 45'-0" 62-153-E Appendix "R" Separation Requirements, Aux. Bldg. and Ctmt. 7 5/94 Drawing l CN U
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Sruct., Elevations 69'#
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2.0 STRUCTURAL COMPONENTS WITHIN THE SCOPE OF LICENSE RENEWAL The Auxiliary Building components were scoped in accordance with the process described in the BGE Integrated Plant Assessment Methodology. The Auxihary Building was scoped using procedure LCM-11S for structural components. The purpose of the scoping is to identify all structural components that provide one of the structure's intended functions identified in Section 1.1.3. These structural components are designated as within the scope of license renewal.
As a result of the scoping,37 structural component types were designated as within the scope oflicense renewal. A summary of the scoping result is in Table 2-1.
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l j Table 2-1 Auxiliary Building Structural Components Within the Scope of License Renewal COMPONENTTYPE INTENDED FUNCrlON(S)
Foundations (Footings, Beams, and Mats) LR&1 and 5 Concrete Column LRG1 and 5 Concrete Walls LR-S-1,2,4,5,6, and 7 Concrete Beams LR-S-1 and 5 Concrete Ground Floor Slabs LR-S-1 and 5 Equipment Pads LRG1 and 5 Elevated Floor Slabs LR-S-1,2,5, and 7 RoofSlabs LR-S-2 and 4 Cast-in-Place Anchors LR-S-1 Grout LRG1 and 5 Concrete Blocks (Shielding) LR-S-2 Fluid Retaining Walls and Slabs LR-S-1 Masonry Block Walls LRG1,2,5,6, and 7 Post-Installed Anchors LR-S-1, and 5 O SteelColumns LR-S-1 and 5 b SteelBeams LR-S-1 and 5 )
LRG1 and 5 Baseplates Floor Framing LR-S-1 and 5 Roof Framing LR G1,4,and5 RoofTruces LR&1,4, and 5 Steel Bracings LR&1 and 5 Platform Ilangers LR-S-1 and 5 Decking LR-S-1 and 5 JetImpingement Barriers LRG2 SteelLiners LR &3 Fire Doors, Jambs, and Hardware LR-S-7 Access Doors, Jambs, and Hardware LR-S-2 Caulking and Scalants LR&2,6, and 7 Watertight Doors LR-S-6 and 7 lead Brick Shielding LRG2 Roll-up Doors LR&2 New Fuel Rack Assembly LR-S-1 Monorail LR&5 Cask Handling Crane Rail / Supports LR-S-1 and 5 Pipe Whip Restraints LR-S-2 Expansion Joints LRG2 and 7 Spent FuelStorage Racks LR&1 AGING MANAGEMENT REVIEW RESUL'IS FINAL REPORT AUXILIARY BUILDING 2-2 REVISION 2
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l 3.0 STRUCTURAL COMPONENTS PRE-EVALUATION Per the BGE Integrated Plant Assessment Methodology, the pre-evaluation task is not conducted on structures. Structural components are assumed to be passive and long-lived and therefore subject to an Aging Management Review. Consequently, Table 2-1 also represents a list of structural component types subject to Aging Management Review.
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4.0 STRUCTURAL COMPONENTS AGING EFFECTS EVALUATION 4.1 EVALUATION l l l The evaluation of the Auxiliary Building structural components within the scope ;
l of license renewal was completed in accordance with BGE procedure, " Component Aging Management Review Procedure for Structures", EN-1-305, Revision 0. This l procedure evaluated all 37 component types identified in Section 2.1 The evaluation accomplished the following:
l (1) Identified POTENTIAL aging mechanisms for each structural component TF- 1 (2) Identified PLAUSIBLE component aging mechamsms for each structural component type or specific components within the component type based l
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- environmentalconditions
- material of construction unpact onintended functions
! Developed attributes for programs to manage the effects of aging from (3) those aging mechanisms identified as PLAUSIBLE.
(4) Evaluated program adequacy to demonstrate that the effects of aging will !
be managed so that the intended function (s) will be maintained for the period of extended operation. j l
These steps are discussed in greater detail in the sections that follow. l l
4.2 AGING MECHANISMS i
4.2.1 Potential Aging Mechanisms l
This step of the aging evaluation identifies aging mechanisms that are considered to be POTENTIAL for a given component type. An aging i l mechanism is considered POTENTIAL for a structural component if the
! evaluation concludes that the aging mechanism could occur in generic applications of the structural component type throughout the plant due to susceptible materials of construction and conducive environmental service conditions.
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A comprehensive list of 18 aging mechanisms was developed that may be applicable to structural component types. This was based on the EPRI !
industry reports prepared for the PWR containment structure and Class I structures, i
Other references used to prepare this list include the following: :
NRC NPAR Reports l IAEA Reports ]
DOE Reports ;
The list of aging mechamsms and materials they affect are in the first l column of Table 4-1. The specific description of each is provided in l Attachment 1 of procedure EN-1-305 or is described in detail in Section 1.0 of the corresponding appendices (A through T) in the aging management review results. !
l Each aging mecharusm was evaluated for applicability (i.e., POTENTIAL) j to the structural component type based on its material of construction and ;
e the environmental conditions where the component type could be located. i f
's This approach ensures all the components within a component type will be ;
evaluated if the potential of degradation exists. l The results of the structural component type POTENTIAL scoping of the component list of aging mechanisms are presented in Table 4-1.
4.2.2 Component Grouping The grouping of structural components is primarily based on their materials and their special functions, if any, that contribute to safety, or in the opinion of the evaluator, warrant special attention. The components are grouped into four categories:
(1) Concrete (including reinforcing steel)
(2) Structuralsteel (3) Architectural items such as doors, roofing materials, and protective coatings (4) Additional components that may have an unique function in the structure I
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i 4.2.3 Plausible Aging Mechanisms The identification of PLAUSIBLE aging mechanisms is accomplished through a careful review of the POTENTIAL aging mechanism list, the l development of which is discussed in Section 4.2.1. A potential aging mechanism is considered plausible if when it is allowed to continue without any additional preventative or mitigative measures, the aging mechamsm would result in the structural component not being able to perform its intended function. An aging meclumism is also considered plausible if there is insufficient evidence to conclude that future degradation will have no impact on the intended functions of the Auxiliary ,
Building structural component. The plausibility determmation is made through a careful consideration of all the factors required to allow the aging degradation to occur. In particular, the aging mechanism is scoped for plausibility on the basis of:
Materialof construction Environmental service conditions G
- Design and construction considerations l ()
- Impact onintended functions Physical conditions of the component The results of the aging mechamsm plausibility scoping is an aging mechanism-component matrix listing the aging mechanism and its disposition. The aging mechanism matrix developed for each structural component type is included in Attachment 2 in the evaluation results.
Aging mechanisms determined to be PLAUSIBLE are provided specific aging management recommendations to mitigate the detrimental effects on the structural components. Table 4-2 summanzes the results of the i plausibility determmation and recommendations for the Auxiliary i Building structuralcomponents.
4.2.4 Aging Management Program Identification l
Once plausible aging mechanisms have been identified, the evaluation is l l continued to determine whether ex.isting plant programs adequately I address the effects of aging for license renewal. If no changes would be needed to existing programs to enable them to manage the effects of aging during the period of extended operation, no further action is required for this aging mechamsm. If existing programs would not manage the effects O AGING MANAGEMENT REVIEW RESULTS FINAL REPORT AUXILIARY BUILDING 4-3 REVISION 2 l
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i of aging during the period of extended operation, an age related degradation inspection could be conducted, modifications could be made i
to existing programs, or new programs could be initiated to adequately manage the effects of aging. This evaluation did not include a determination of whether recommended changes to existing programs or new program recommendations would actually be implemented or which programs would be included in the FSAR Supplement.
4.2.5 Aging Management Recommendations The evaluation of all structural component types in the Auxiliary Building identified a total of 13 aging mechanisms that have the POTENTIAL to degrade these components. A detailed review of the specific component intended functions, material of construction and its basis of design and l construction identified PLAUSIBLE component aging meclu'nisms as shown in the second column of Table 4-2. In some cases, the conclusicen that the aging mechanism is PLAUSIBLE was made because the condition of the component was not available or could not be readily verified due to lack of accessibility.
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,b Recommended aging management activities include actions to perform l condition assessment, to verify conditions conducive to degradation do not exist, and to develop inspection and monitoring prodrams to ensure degradation can be detected and corrective actions can be taken.
The following is a summary of the recommendations:
(1) Verify the water chemistry of groundwater and initiate follow on ;
activities, as necessary, based on test results.
(2) Continue visual inspection of coated structural steel components in accessible areas.
(3) Develop an age related degradation inspection program for coated surfaces of structural steel components that are not readily accessible.
i j (4) Continue monitoring under the Appendix R Program caulking and l scalants and expansion joints that serve as rated fire barriers.
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i (5) Develop a new program to address the inspection and maintenance l of cattiking and sealants and expansion joints that do not serve as fire barriers.
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Table 4-1 List of Potential Aging Mechanisms for Auxiliary Building Stmetural Components t
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1 Potentialto Affect l Aging Mechanism Description Auxiliary Building? Materials Affected Freeze-Thaw Yes Concrete Leaching of Calcium Hydroxide Yes Concrete
! Aggressive Chemicals Yes Concrete Reaction with Aggregates Yes Concrete Corrosionin Embedded Steel /Rebar Yes Steel, Concrete Creep No Concrete
! Shrinkage No Concrete Abrasion and Cavitation No Concrete l Cracking of Masonry Block Walls Yes Block Walls I i Settlement Yes Structure foundation i p Corrosionin Steel Yes Steel V Corrosionin Liner Yes Steel Liners (Carbon and Stainless)
Corrosion in Tendons No* Steel ,
Prestressing Losses No* Steel I Weathering Yes Caulking and Sealants, I j Expansion Joints l Elevated Temperature Yes Concrete Irradiation Yes Concrete, Steel l Fatigue Yes Concrete, Steel
- There are no Tendons in the Auxiliary Building l
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m b b LIFE CYCLE MANAGEMENT UNIT Table 4-2 Auxiliary Building Aging Effects Evaluation Summary STRUCIURAL PLAUSIBLE COMPONENTS AGING MECIIANISM RECOMMENDATION REMARKS Concrete Columns None None See justification in Appendices D, R, E and T.
Concrete Beams, Roof Stabs None None See justification in Appendices D, E and T.
G:ound FloorSlabs & None None See justification in Appendices D, R. E and T.
Equipment Pads Elevated FloorStabs None None See justification in Appendices D, R, E and T. L CastMlace Anchors Corrosion in steel See im,umw.dotion for " Steel Columns" See justificationin Appendices K ,
Grout None None See justificaticein Appendices R S and T.
Post-installed Anchors Corrosionin steel See retummendation for " Steel Columns" Seejustificationin Appendzx K.
SteelColumns Corrosionin steel All exposed surfaces of structural steelu,up-sts am covered by a See justificationin Appendix K protective coating. For accessible areas, significant coating degradation and/or the presence of corrosum will be identified, an issue nport written, and corrective action taken through the following existmg site Prograna PEG-7, System Walkdowns QIr2-100, Issue Reportmg MN.3100, P.otective Coating Program For those structural steel components not readdy accessible, signifwant coating degradation and/or the pnsence of corrosum will be determmed uti'izing an age elated degradation inspectiort Steel Beams Corrosxm in steel See im,ums.dation for " Steel Columns" See justification in Appendix K.
Baseplates Corrosion in steel See 1m,oma.dation for " Steel Columns" See justificationin Appendix K Floor Framing Corrosumin steel See n m ume.dation for " Steel Columns
- Seejustificationin Appendix K AGING MANAGEMENT REVIEW RESULTS FINAL REPORT AUXILIARY BUILDING 4-7 REVISION 2
p p N) O LIFE CYCLE MANAGEMENT UNIT Table 4-2 Auxiliary Building Aging Effects Evaluation Summary STRUCTURAL PLAUSIBLE COMPONENTS AGING MEC11ANISM RECOMMENDATION REMARKS Roof Framing / Trusses Cormnon in steel See muums.datxn for" Steel Columns" See justificationin Apperdtx K.
Steel Bracings Cormnonin steel See muums.dation for " Steel Columns
- Seejustificationin Appendix K.
Platform Hangers Corrosionin steel See muums.dation for " Steel Columns" Seejustifationin Appendix K Decking Corrosion in steel See ,wvums.dation for " Steel Columns
- See justificationin Appendix K Jet Impingement Barners Corrosion in steel See muum m .dation for " Steel Columr s' See justificationin Appendix K Pipe Whip Restraints Conosion in steel See muumm.dation for *SteelColumr# See justificatxn in Appendtx K.
Monorail Corrosionin steel See muuma.dation for " Steel Columns" See justificationin Appendix K Cask Handling Crane Corrosionin steel See muum s.dation for " Steel Columns" See justificatbnin Appendix K Rail / Supt Expansion Joints Weathering Expansionjoirns which perform a fire tumer function will be addressed by Seejustification in Appendix O.
the Apgendix R Program. For expansionjoires which perform an intended funcnon other than fire barrier, an inspection and iisa - 2 m wM will idernify degradation and ensure correctrve action is taken before the componera losses its ability to perform its interxled funcuon will be developed.
"Ihe resolution to Issue Repott IR1995-01698 will form the tusis for this Program.
Caulking and Sealants Weathering Caulking and scalants which perform a fire bamer funcnon will be adhessed See jushfication in Appendix O.
by the Appendix R Program. Ibr caulkmg and scalaras utiich perform an unended funcuen other than fire barrier, an inspecuon and mairmenance program which will identify degradation and ensure correcove action is taken before the componera losses its ability so perform its intended funcuon will be developed. The resolution to issue Report IR199541698 will form the b sis for this program.
l AGING MANAGEMENT REVIEW RESULTS FINAL REPORT AUXILIARY BUILDING 4-8 REVISION 2
U(3 Q x.J (D
V LIFE CYCLE MANAGEMENT UNIT Table 4-2 Atixiliary Building Aging Effects Evaluation Summary STRUCTURAL PLAUSIBLE COMPONENTS AGING MECIIANISM RECOMMENDATION REMARKS g,*b Aggressive chemacalcorrosmn at cin for'Foundaten Mat" See Aging mediarusms are plausible only for the in embedded steel /rebar below grade porton of the Auuliary Buddmg walls.
Seejusuficationin Appendices A,B C,D,E.R,E and T.
^ ""
The observation wells, instaDed during construction, can be restored to Foundation Mat g g See justifation in Appendices B, C, D, E. J. E morutor the groundwater fluctuation and to sample the groundwater and T.
for water quality testing. This data will be used to evaluate the impact of chemical attacks on the exterior surface of the components.
In cases where the groundwater chemistry investigation detemunes that degradation of the foundation mat is plausible (such as a pH less than 4.0), additional investigations or awh may be required.
Fluid RetammgWells & Slabs None None See justifation in Appendices D, and S.
Spent FuelStorege Racks None None See justfntionin Appendix L Steel Liner Corrosion in liner None See justification in Appendix L (SS Spent FuelPoolljner)
New FuelRack Assembly CorrosioninSteel See recommendation for " steel columns
- Seejustificationin Appendix K Fire Doors, Jambs, and Corrosion in Steel See muu ma. .dation for ' steel columns
- Seejustificationin Appendix K llaniware Access Doors, Jambs, and Corrosionin Steel See muumm.dation for ' steel columns
- Seejustificationin Appendix K Hardware rod-Up Doors Corrosion in Steel See mv..mmi.dation for " steel columns" SeejustEntionin Appendix K Watertight Doors CorrosxminSteel See mumm.ei.dation for " steel columns
- Seejustifntionin Appendix K AGING MANAGEMENT REVIEW RESULTS FINAL REPORT AUXILIARY BUILDING 4-9 REVISION 2
LIFE CYCLE MANAGEMENT UNIT Table 4-2 Auxiliary Building Aging Effects Evaluation Summary STRUCIURAL PLAUSIBLE COMPONENTS AGING MECIIANISM RECOMMENDATION REMARKS lead Brick Shieldmg None None Imad is not subject to any aging medwusms notedin Appendices A tot.
Concrete Blocks (Shielding) None None See pastificationin Appendix I Masonry Block Walls None None See justificationin Appendix I AGING MANAGEMENT REVIEW RESULTS FINAL REPORT AUXILIARY BUILDING 4-10 REVISION 2 1
LIFE CYCLE MANAGEMENT UNIT O
5.0 PROGRAM EVALUATION 5.1 PROGRAM ADEQUACY EVALUATION Program adequacy evaluations were completed in accordance with EN-1-305, !
Revision 0, for those programs or aging degradation management alternatives developed to address PLAUSIBLE component aging mechanisms The evaluation of programs or aging management alternatives considered the following criteria as :
a means of establishing the adequacy of specific CCNPP programs:
- 1. Adequate programs must ensure management of the effects of aging for those structural components subject to plausible aging mechanisms.
- 2. Adequate programs must contain acceptance criteria against which the need for corrective action will be evaluated, and ensure that timely corrective action will be taken when these acceptance criteria are not met.
- 3. Adequate programs must be implemented by the facility operating procedures and reviewed by the onsite review committee.
O The results of the program adequacy evaluations are provided in Section 5.2.
V 5.2 STRUCTURAL COMPONENTS SUBJECT TO ADEQUATE PROGRAMS 5.2.1 Existing Programs l
The program evaluation task reviewed all existing CCNPP programs that ,
were established to monitor, inspect, and repair Auxdiary Building l structural components that are degraded by identified plausible agmg ;
mechanisms. ;
Procedure OI-24D and Performance Evaluation, PE 0-67-2-O-M, for the monitoring of leakage in the Spent Fuel Pool, can be relied on to manage the effects of aging without any modifications.
The Appendix R Program, implemented through procedure STP-F-592-1/2 l
for penetration fire barrier inspection, is adequate to manage the effects of aging for caulking and scalants and expansion joints which function as fire barriers without any modification.
I PEG-7 in combination with QI 2-100 and MN-3-100 for identifying, documenting, and correcting significant coating degradation are adequate for managing the effects of corrosion in accessible steel components.
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AGING MANAGEMENT REVIEW RESULTS FINAL REPORT AUXILIARY BUILDING 5-1 REVISION 2
LIFE CYCLE MANAGEMENT UNIT l 0 v
5.2.2 Modified Existing Procrams This section provides the summary results for those structural components that were determined to have an existing CCNPP Program / Activity that with modification would become an adequate program to manage the effects of aging during the renewal period. The evaluation started from evaluating structural component types and applicable aging mechanisms and has focused to specific components or locations. No modified existing programs were identified to manage the effects of aging into the license renewal period.
5.2.3 New Programs This section provides the summary results for those structural components that were determined to require a new CCNPP Program / Activity to be created as an adequate pmgram to manage the effects of aging during the renewal period. Components that can be managed by the creation of such new programsinclude the foHowing:
Below crade portion of Auxiliary Buildine wall: An investigative program starting with testing the groundwater chemistry should be developed to O)
(_. determine if there is any aggressive chemical attack on the Auxiliary Building exterior walls or plausible corrosion in embedded steel /rebar.
Inspection of the exterior, below grade surfaces and additional excavation and testing may be necessary if results from the investigative tests are not favorable.
Foundation Mat: An investigative program startmg with testing the groundwater chemistry should be developed to determine if there is any aggressive chemical attack on the foundation mat or plausible corrosion in embedded steel /rebar. Inspection of the exterior, below grade surfaces and additional excavation and testing may be necessary if results from the investigative tests are not favorable.
Caulking and Sealants and Expansion Toints: A periodic inspection and maintenance program should be developed for components not covered by the Appendix R fire barrier inspection program. The resolution to Issue Report IR1995-01698 will address the requirements for the inspection and maintenance of caulkmg and sealants and expansion joints which do not function as fire barriers and are therefore not covered by the Appendix R Program.
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AGING MANAGEMENT REVIEW RESULTS FINAL REPORT AUXILIARY BUILDING 5-2 REVISION 2 i
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i LIFE CYCLE MANAGEMENT UNIT l A lU Non-accessible Structural Steel: An age related degradation inspection, as defined in the BGE Integrated Plant Assessment Methodology, should be conducted for structural steel components that are not readily accessible.
The ARDI Program must provide requirements for identification of a representative sample of components for inspection, the inspection sample I size, appropriate inspection techniques, and requirements for reporting of results and corrective actions.
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AGING MANAGEMENT REVIEW RESULTS FINAL REPORT l
AUXILIARY BUILDING 5-3 REVISION 2
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! LIFE CYCLE MANAGEMENT l
''"'^""*""*"**"""^""*"**"
l0 For the Auxiliary Building l
Aging Management Review l l !
Total Paggs j Attachment 1, Potential Aging Mechanisms Applicable to Structural Components 3 Attachment 2, Plausible Aging Mechanisms Applicable to Structural Components 3 Attachment 3, Structural Components Aging Mechanism Matrix Codes 3 Attachment 4, Aging Management Review Results 4 l
Attachment 5, Adequate Program Evaluation 14 l Attachment 6, Not Used 0 Attachment 7, Walkdown Report -CCNPP Auxiliary Building, November,1994 5 Attachment 8, Attributes in New Program 10 Appendices !
Appendix A - Freeze-Thaw 6 Appendix B - Leaching of Calcium Hydroxide 7 l Appendix C - Aggressive Chemicals 5 l
Appendix D - Reactions with Aggregates 6 Appendix E - Corrosion of Embedded Steel /Rebar 5 Appendix F - Creep 4 Appendix G - Shrinkage 3 Appendix 11 - Abrasion and Cavitation 2 Appendix I - Cracking of Masonry Block Walls 5 l Appendix J - Settlement 4 Appendix K - Corrosion of Steel 5 Appendix L - Corrosion of Liner 5 Appendix M - Corrosion of Tendons 2 Appendix N - Prestress Losses 2 Appendix 0 - Weathering 3 Appendix P - Not Used 0 ;
l Appendix Q - Not Used 0 l l I l
Appendix R - Elevated Temperature 4 l Appendix S -Irradiation 4 Appendix T - Fatigue 9 O
k)' AGING MANAGEMENT REVIEW RESULTS FINAL REPORT AUXILIARY BUILDING REVISION 2 l l
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1 Attachment 1 Potential Aging Mechanisms Applicable to Structural Components O
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Atte.ch...Jnt 1 Potential Aging Mechanisms Applicable to Structural Components REVISION: 2 DATE: 5/7/96 STRUCTURE NAME: Auxiliarv Buildina Structure SYSTEM NUMBER: None Sheet 2_ of 3 IN SCOPE POTENTIAL AGING MECHANISMS APPLICABLE TO CONCRETE / ARCH. COMPONENTS REMARKS 7 STRUCTURAL COMPONENTS A B C D E F G H I J R S T O Foundations (Footings, Beams & - 4 4 4 4 - - -
NA 4 - V - - LR Functions LR-S-1,5 Mits) 4 - - -
NA - 4 4 4 - LR Functions LR-S-1, 5 Concrete Columns - - - -
4 4 4 4 4 - - - NA - 4 4 i - LR Functions LR-S-1, 2, 4, 5, 6, 7 Concrete Walls 4 - - - -
NA - - 4 4 - LR Functions LR-S-1,5 Concrete Beams - - -
4 - - - - NA - - 4 4 - LR Functions LR-S-1, 5 Concrete Ground Floor Stabs - - -
Concrete Equipment Pads - - - 4 - - - - NA - 4 4 4 - LR Functions LR-S-1,5 ElsvEted Floor Slabs - - - 4 - - - - NA - 4 4 4 - LR Functens LR-S-1,2,5,7 Roof Stabs - - - 4 - - - - NA - - 4 4 - LR Functions LR-S-2,4 Grout - - - - - - - - NA - 4 4 - - LR Functions LR-S-1,5 Concrete Blocks (Shie.: ling) - - - - - - - - 4 - - 4 - -
LR Function LR-S-2 Fluid Retaining Walls & Stabs - - - 4 - - - -
NA - - 4 - - LR Function LR-S-1 Misonry Block Walls - - - - - - - - 4 - - 4 - - LR Functions LR-S-1, 2, 5, 6, 7 Exptnsion Joints - - - - - - - - NA - - - - 4 LR Function LR-S-2, 7 ,
Ceulking and Sealants - - - - - - - - NA - - - - 4 LR Function LR-S-2,6,7 -
Legend: A Freeze-thaw G Shrinkage M Corrosion in tendons S trradiation B Leachir:;; of calcium hydroxide H Abrasion and cavitation N Prestressing losses T Fatigue C Aggressive chemicals 1 Cracking of masonry block walls O Weathering U (Not Used)
D Reaction with aggregates J Settlement P (Not Used) V (Not Used)
E Corrosion in embedded steet/rebar K Corrosion in steef Q (Not Used) NA Not applicable F Creep L Corrosion in Liner R Elevated temperature - Not potential
AttacftwJnt 1 Potential Aging Mechanisms Applicable to Structural Components i
REVISION: 2 DATE: 5/7/96 STRUCTURE NAME: Auxiliary Building Structure SYSTEM NUMBER: _None_ Sheet 3 of 3 IN SCOPE POTENTIAL AGING MECHANISMS APPLICABLE TO STEEL COMPONENTS REMARKS STRUCTURAL (SEE APPENDICES A THROUGH T FOR DEFINITIONS OF AGING MECHANISMS)
COMPONENTS K L M N R S T .
Stact Columns 4 -
NA NA - - 4 LR Functions LR-S-1, 5 Staat Beams 4 -
NA NA - - 4 LR Functions LR-S-1, 5 Bzseplates 4 -
NA NA - - 4 LR Functions LR-S-1, 5 Floor Framing 4 - NA NA - - i LR Functions LR-S-1,5 Roof Framing / Trusses 4 - NA NA - - 4 LR Functions LR-S-1, 4, 5 Stxl Bracings 4 -
NA NA - - 4 LR Functions LR-S-1, 5 Platform Hangers 4 -
NA NA - - 4 LR Functions LR-S-1, 5 Decking 4 -
NA NA - - i LR Functions LR-S-1,5 Jzt lmpingement Barriers 4 -
NA NA - - -
LR Function LR-S-2 Steet Liners - 4 NA NA - - -
LR Function LR-S-3 Firs Doors. Jambs,& Hardware 4 -
NA NA - - - LR Function LR-S-7 Acesss Doors, Jambs,& Hardware 4 - NA NA - - -
LR Function LR-S-2 Wst:rtight Doors 4 - NA NA - - LR Functions LR-S-6, 7 Lead Brick Shielding - -
NA NA -- - -
LR Function LR-S-2 Roll-up Doors 4 -
NA NA - - -
LR Function LR-S-2 NJw Fuel Rack Assembly 4 - NA NA - - -
LR Functions LR-S-1 Monorail 4 -
NA NA _ _
LR Functions LR-S-5 Catk Handling Crane Rail /Spts 4 -
NA NA - - 4 LR Functions LR-S-1,5 Pips Whip Restraints 4 - NA NA - - - LR Function LR-S-2 Cast-in-place Anchors 4 - NA NA - - - LR Function LR-S-1 Post-Installed Anchors 4 - NA NA - - - LR Functions LR-S-1,5 Spent Fuel Storage Racks - - - - - - - LR Functions LR-S-1 Leg:nd: A Freeze-thaw G Shrinkage M Corrosion in tendons S Irradiation B Leaching of calcium hydroxide H Abrasion and cavitation N Prestressing losses T Fatigue C Aggressive chemicals I Cracking of masonry block walls O Weathering U (Not Used)
D Reaction with aggregates J Settlement P (Not Used) V (Not Used)
E Corrosion in embedded steet/rebar K Corrosion in steel Q (Not Used) NA Not applicable F Creep L Corrosion in Liner R Elevated temperature -
Not potential
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i Attachment 2 Plausible Aging Mechanisms Applicab e to Structural Components 4
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m U d d ATTACHMENT 2: PLAUSIBLE AGING MECHANISMS APPLICABLE TO STRUCTURAL COMPONENTS REVISION: 2 DATE: 5/7/96 STRUCTURE NAME: Exiliarv Buildino Structure SYSTEM NUMBER: None Sheet 2_ of 3 LR PLAUSlBLE AGING MECHANISMS APPLICABLE TO CONCRETE / ARCH. COMPONENTS REMARKS STRUCTURAL (SEE ATTACHMENT 4 FOR JUSTIFICATION)
COMPONENTS A B C D E F G H I J R S T O Foundations (Footings, Beams & -
102 PA 103 PB - - - NA 105 -
107 - -
Mits)
Concrete Columns - - - 103 - - - -
NA -
106 107 108 -
Concrete Walls 101 102 PA 103 PB - - -
NA - 106 107 108 -
Concrete Beams - - -
103 - - - -
NA - - 107 108 -
Concrete Ground Floor Slabs - - -
103 - - - - NA - -
107 108 -
Concrete Equipment Pads - - - 103 - - - -
NA -
106 107 108 -
Elevated Floor Stabs - - -
103 - - - - NA - 106 107 108 -
Roof Slabs - - -
103 - - - - NA - - 107 108 -
Grout - - - - - - - -
NA -
106 107 - -
Concrete Blocks (Shielding) - - - - - - - - til - - 107 - -
Fluid Retaining Walls and Stabs - - -
103 - - - - NA - -
107 - -
Mrsonry Block Wa!!s - - - - - - - -
111 - -
107 - -
Expansion Joints - - - - - - - -
NA - - - -
PF Cculking and Sealants - - - - - - - -
NA - - - - PF Legend: A Freeze-thaw G Shrinkage M Corrosion in tendons S trradiation B Leaching of calcium hydroxide H Abrasion and cavitation N Prestressing losses T Fatigue C Aggressive enemicals I Cracking of masonry block walls O Weathering U (Not Used)
D Reaction with aggregates J Settlement P (Not Used) V (Not Used)
E Corrosion in embedded steel /rebar K Corrosion in steel O (Not Used) NA Not applicable F Creep L Corrosion in Liner R Elevated temperature -
Not potential
y- s n b
ATTACHMENT 2: PLAUSIBLE AGING MECHANISMS APPLICABLE TO STRUCTURAL COMPONENTS REVISION: 2 DATE: 5/7/96 STRUCTURE NAME: Auxiliary Buildino Structure SYSTEM NUMBER. None Sheet 3.of 2 LR PLAUSIBLE AGING MECHANISMS APPLICABLE TO STEEL COMPONENTS REMARKS STRUCTURAL (SEE ATTACHMENT 4 FOR JUSTIFICATION)
COMPONENTS K L M N R S T Stael Columns PD -
NA NA - -
108 Stiel Beams PD -
NA NA - -
108 B seplates PD - NA NA - -
108 Floor Framing PD - NA NA - -
108 Roof Framing / Trusses PD -
NA NA - - 108 St:et Bracings PD -
NA NA - -
108 Plitform Hangers PD - NA NA - -
108 Drcking PD - NA NA - -
108 JIt Impingement Barrier PD -
NA NA - - -
Strel Liners -
PE NA NA - - -
Firs Doors, Jambs, & Hardware PD -
NA NA - - -
Access Doors, Jambs,& hardware PD -
NA NA - - -
Watertight Doors PD - NA NA - - -
Lsad Brick Shielding - - NA NA - - -
Roll-Up Doors PD - NA NA - - -
N3w Fuel Rack Assembly PD -
NA NA - - -
Monorail PD -
NA NA - - -
Cask Handling Cranc Rail /Supts PD -
NA NA - -
108 Pipe Whip Restraints PD -
NA NA - - -
Cast-in-place Anchors PD - NA NA - - -
Post-installed Anchors PD -
NA NA - - -
Spent Fuel Storage Racks - - NA NA - - -
Legend: A Freeze-thaw G Shrinkage M Corrosion in tendons S Irradiation B Leaching of calcium hydroxide H Abrasion and cavitation N Prestressing losses T Fatigue C Aggressive chemicals 1 Cracking of masonry block walls O Weathering U (Not Used)
D Reaction with aggregates J Settlement P (Not Used) V (Not Used)
E Corrosion in embedded steet/rebar K Corrosion in steel Q (Not Used) NA Not applicable F Creep L Corrosion in Liner R Elevated temperature -
Not potential
O Attachment 3 Structural Components Aging Mechanism Matrix Codes 1
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ATTACHMENT 3
,'~N
'y/ STRUCTURAL COMPONENT - AGING MECHANISM MATRIX CODES REVISION: 2 DATE:_5/7/96 STRUCTURE NAME: Auxiliary Building SYSTEM NUMBER: None Sheet 2 of 3 CODE JUSTIFICATION REMARKS 101 See Appendix A 102 See Appendix B 103 See Appendix D 104 See Appendix H 105 See Appendix J l 106 See Appendix R 107 See Appendix S 108 See Appendix T
- ' v
109 Not Used 110 See Appendix L 111 See Appendix l l
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t ATTACHMENT 3 f STRUCTURAL COMPONENT- AGING MECHANISM MATRIX CODES REVISION: 2 DATE: 5/7/96 STRUCTURE NAME: Auxiliary Building SYSTEM NUMBER: None Sheet 3 of 3 l CODE JUSTlFICATION REMARKS PA See Appendix C PB See Appendix E PC Not Used l PD See Appendix K PE See Appendix L
, . PF See Appendix 0 l
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a s s J.-....__ --. .a ._ . a a _s . ~-2 a~ us. a a ,.-.a-L 4
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Attachment 4 6
t Aging Management Review Results l
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,-- o n q,Y Attachment 4
SUMMARY
OF AGING MANAGEMENT REVIEW RESULTS REVISION:_2_
DATE 5/7/96 STRUCTURE / SYSTEM NUMBER: None STRUCTURE NAME: Auxiliary Building COMPONENTSAFFECTED AGING MECIIANISMS CONCRETE STEEL ARCH. PROGRAM / COMMENT Freeze-Thaw None None None Not Needed I. caching of Ca(OH)2 None None None Not Needed Aggressive Chemicals 1. Belowgradeportion None None None existing. Need to investigate of Aux. Bldg. walls ground water. I
- 2. Foundation Mat Reaction with Aggregates None None None Not Needed Corrosion of Embedded 1. Below grade portion None None None existing. Need toinvestigate Steel /Rebar of Aux. Bldg. walls ground water.
- 2. Foundation Mat Creep None None None Not Needed Shnnkage None None None Not Needed Abrasion / Cavitation None None None Not needed because this aging mechanism does not exist at the Auxthary Building.
Cracking of Masonry None None None Not Needed Block Walls Settlement None None None Not Needed Sheet 2_ of 4
O O O Attachment 4
SUMMARY
OF AGING MANAGEMENT REVIEW RESULTS REVISION:__L DATE: SU/96 STRUCTURE / SYSTEM NUMBER: None STRUCTURE NAME- Auxiliary Building COMPONENTSAFFECTED AGING MECIIANISMS mNCREFE STEEL ARCH. PROGRA14/ COMMENT Corrosionin Steel None All structural None PEG-7, MN-3-100, QL-2-100, ARDI.
steelmembers Corrosionin Liner None Sensitized zone of None Procedure OI-24D, Rev. O and the Spent Fuel Performance Evaluation, Pool Liner PE 0-67-2-O-M Corrosion in Tendons None None None Not needed because there are no tendonsin the Auxiliary Building Prestressing Losses None None None Not needed because there are no tendonsin the Auxiliary Building Weathering None None 1. Caulking Appendix R Program for and Scalants components with fire protection
- 2. Expansion function. For non-Appendix R joints components, develop aninspection and maintenance program to identify degradation and ensure corrective actionis taken. The resolution to Issue Report IR1995-01698 to form the basis of this Program.
Elevated Temperature None None None Not Needed Sheet 3_ of 3
O O O ,
Attachment 4
SUMMARY
OF AGING MANAGEMENT REVIEW RESULTS REVISION:_2_
DATE 5n/96 STRUCTURE / SYSTEM NUMBER: None STRUCTURE NAME- Auxiliary Building COMPONENTSAFFECTED AGING MECHANISMS CONCRETE STEEL ARCH. PROGRAM / COMMENT Irradiation None None None Not Needed Estigue None None None Not 'Teeded Sheet L of A
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. Attachment 5 l Adequate Program Evaluation J
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Sheet 1 of 14
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ADEQUATE PROGRAM EVALUATION l
REVISION:_2_ DATE: 5/7/96 !
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STRUCTURE / SYSTEM NUMBER:.&ne. STRUCTURE NAME: Auxiliary Building STRUCTURAL COMPONENT DESCRIPTION: All accessible structural steel members AGING MECilANISM DESCRIPTION: Corrosion of steel j CCNPP PA or Task ID: MN-3-100. PEG-7. OL-2-100 Criteria 1: Adequate programs must ensure mitigation of the effects of age-related degradation for the SSCs within the scope oflicense renewal .
DISCOVERY DESCRIPTION / BASIS:
- 1. Is there a frequency interval in the PA or Task?
YES _X. NO _
( Basis: System Engineer Walkdowns as directed by PEG-7 are conducted periodically as mandated by system performance, plant operating conditions, or as required by i
plant management. Walkdowns can be job specific or outage related but otherwise typically occur on a monthly basis.
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- 2. Is the frequency interval consistent with industry standards, industry experience, experience !
unique to Calvert Cliffs, or vendors' recommendations?
l YES X NO _ j 1
Basis: The PEG-7 walkdown frequency is consistent with industry standards and can be modified as necessary to reflect unique plant operating conditions specific to CCNPP.
- 3. Will the PA or Task be applicable to all structural components under the same component type?
YES X NO_
1 Basis: All coated surfaces in areas that are " reasonably accessible" are visually inspected during the PEG-7 activity.
O Sheet 2 of 14
O Attachment 5 - Adequate Program Evaluation (continued)
REVISION: _2_. DATE: 5/7/96 AGING MECHANISM: Corrosion of steel CCNPP PA or TASK ID: MN-3-100. PEG-7. OL-2-100 Criteria 2: Adequate programs must contain acceptance criteria against which the need for corrective action will be evaluated, and ensure that timely corrective action will be taken when these acceptance criteria are not met.
ASSESSMENT / ANALYSIS / CORRECTIVE ACTION DESCRIPTION / BASIS:
- 1. Does the PA or Task have an action or alert value or condition parameter to detennine the need for corrective action?
YES _X__ NO _.
Basis: There is no quantitative alert value to determine the need for corrective action.
PEG-7 allows for degraded coatings to be documented on a checklist which is then used to prioritize corrective actions. MN-3-100 specifies appropriate r~s technical procedures for corrective action based on the coatings service level.
- 2. Does the action value or condition provide sufficient indication of degradation to ensure that there will not be a functional failure prior to the next PA or Task?
YES X NO _
Basis: Conditions adverse to quality and functionality, indications of equipment stress or abuse, safety or fire hazards, and general housekeeping deficiencies are noted durine PEG-7 system walkdowns conducted monthly. Structural degradation occurs at a sufficiently slow rate such that monthly inspections would detect degradation before loss of function could occur.
- 3. Will the action value or condition parameter remain the same during the renewal period ?
YES X NO _
Basis: The corrective actions and condition parameters are based on inspection of the surface condition of the painted component. This approach does not need to be revised during the renewal period.
Sheet 1 of 14
Attachment 5 - Adequate Program Evaluation (continued)
REVISION:__2.__ DATE: 5/7/96 AGING MECIIANISM: Corrosion of steel CCNPP PA or TASK ID: MN-3-100. PEG-7. 01,2-100
- 4. Does the PA or Task ensure that corrective action is taken?
YES _X___ NO _
1 Basis: PEG-7 reauires deficiencies to be documented on a system walkdown report.
Conditions adverse to quality will result in the initiation of an Issue Report per OL-2-100 reauirements. MN-3-100 invokes the appropriate technical procedure to ensure proper application and that a qualified protective coating is used.
1
- 5. Does the PA or Task ensure that the corrective action is appropriately scheduled? i YES X NO _
Basis: OL-2-100 assiens a due date for corrective action to occur. The completion date l
(p
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is driven by engineerine indement based on the condition of the degraded coating and its contribution to the component's intended function .
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Attachment 5 - Adequate Program Evaluation (continued) l REVISION:_l_ DATE: 5/7/96 I
l AGING MECHANISM: Corrosion of steel CCNPP PA or TASK ID: MN-3-100. PEG-7. OI 2-109 i
Criteria 3: Adequate programs must be implemented by the facility operating procedures and reviewed by the onsite review committee.
CONFIRMATION / DOCUMENTATION DESCRIPTION / BASIS:
- 1. Does the PA or Task have a review / approval process?
YES_X. NO _
Basis: The procedure requires sismatures from appropriate levels of supervision (i.e.,
POSRC, Manager of Calvert Cliffs Nuclear Power Plant, and GSOA) after it is submitted by the responsible enstineer.
( 2. Does the PA or Task have a change / revision process?
YES_X. NO _
Basis: The " RECORD OF REVISION AND CHANGES" of the orocedure documents the changes to the nrocedure.
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- ( Attachment 5 l (%
ADEQUATE PROGRAM EVALUATION (continued) i l STRUCTURE / SYSTEM NUMBER: None STRUCTURE NAME: Auxiliary Bc:! ding i STRUCTURAL COMPONENT DESCRIPTION: Soent Fuel Pool I iner l
l AGING MECHANISM DESCRIPTION: Corrosion of liner CCNPP PA or Task ID: OI-24D. Rev. O. Ooerating Inctructions for the SFP Cooling - Infrequent Ooerations and PE 0-67-2-O-M Criteria 1: Adequate programs must ensure mitigation of the effects of age-related degradation for the SSCs identified as within the scope of license renewal.
DISCOVERY DESCRIPTION / BASIS:
- 1. Is there a frequency interval in the PA or Task?
YES X NO Basis: Performance Evaluation. PE 0-67-2-O-M. reference in Section 6.1 of OI-24D requires a monthly insnection of all SFP " telltale valves" a 2. Is the aequency interval consistent with industry standards, industry experience, experience unique to Calvert Cliffs, or vendors' recommendations?
YES X NO Basis: The one month insnection interval has been on going for many years and. to date. has always met the acceptance criteria of the procedure with resoect to lenkage from the SFP (less than 1000 cc in a 24 hr oeriod) and is considered accentable for identifying SFP lenkage during the oeriod of extended operation.
- 3. Will the PA or Task be applicable to all structural components under the same component type?
YES X NO Basis: There is only one steel liner (the SFP I.iner) in the Auxiliary Building.
l Sheet j_ of.14
-. . . . . . . _ . - . . - ~ - _ . _- . = _ .
9 Attachment 5 - Adequate Program Evaluation (continued) l REVISION: 2 DATE: 5/7/96 AGING MECHANISM DESCRIPTION: Corrosion of liner CCNPP PA or Task ID: OI-24D. Rev. O. Ooernting Instructinns for the SFP Cooling - Infreauent ;
Ooerations and PE 0-67-2-O-M
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Criteria 2: Adequate programs must contain acceptance criteria against which the need for
, corrective action will be evaluated, and ensure that timely corrective action will be :
taken when these acceptance criteria are not met.
ASSESSMENT / ANALYSIS / CORRECTIVE ACTION DESCRIPTION / BASIS:
- 1. Does the PA or Task have an action or alert value or condition parameter to determine the need for corrective action? !
YES . X NO l i
Basis: Eer Section 6.1.B.10. if lenkage rate exceeds 2 cc in a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> oeriod. from any telltale l valve. and if boron is detected. an Issue Renort to renair the leak will be submitted. l l
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- 2. Does the action value or condition provide sufficient indication of degradation to ensure that ,
there will not be a functional failure prior to the next PA or Task? l 1
YES X NO !
Basis: Due to the fact that the insnection intervals are short (one monthL any lenkage between insnections is easily made up by the SFP pumn which has a caoacity of 160 gpm and is
. conctantly avniinhle to make u3 losses. The Soent Fuel Pool Liner is a fluid retaining boundarv only. It does not orovide any structural sunoort function. Structural integrity is maintained by the surrD.upsing concrete. Therefore. leakage detection and trending is an accentable techniane for ensuring that the soent fuel nool liner is capable of nerforming its intended function under all design conditions reauired by the CLB. The surrounding concrete has been evaluated for the effects of borated water lenkage and a determination made that minor lenkage will not affect the structural integrity function of the concrete including embedded rebar.
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- 3. Will the action value or condition parameter remain the same during the renewal period?
YES X NO Sheet 7 of 14
Attachment 5 - Adequate Program Evaluation (continued)
REVEION: 2 DATE: 5/7/96 AGING MECHANISM DESCRIPTION: Corrosion of liner CCNPP PA or Task ID: OI-24D. Rev. O. Ooeratino Instructions for the SFP Cooling Infrequent Ooeratinns and PE 0-67-2-0-M Basis: The corrective actions and condition parameters prescribed in OI-24D and PE 0-67 l O-M are based on detectina very small amounts of lenkina borated water from the SFP.
as discucced above. This anoroach does not need to be revised durine the oeriod of l
extended oneration.
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Sheet _8_ of _g
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i Attachment 5 - Adequate Program Evaluation (continued) lDQ i
j REVISION: 2 DATE: 5/7/96 i
AGING MECHANISM DESCRIPTION: Corrosion of liner l l
CCNPP PA or Task ID: OI-24D. Rev. O. Ooerating Instructions for the SFP Cooling - Infrequent ,
Operations and PE 0-67-2-O-M l 1
1
- 4. Does the PA or task ensure that corrective action is taken?
i YES X NO l l
l Basis: Ooerating Instruction 24-D requires an Issue Reoort to be generated to document the need for renair. iflenbge exceeds a certain action value. as noted above.
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- 5. Does the PA or Task ensure that the corrective action is appropriately scheduled? l l
YES X NO l l l l Basis: The Issue Reoort orocram (OL-2-100) will insure that action to correct the deficient condition is anoropriately scheduled.
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O Sheet 9 of 14
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"T Attachment 5 - Adequate Program Evaluation (continued) l (O
REVISION: 2 DATE: 5/7/96 l l
AGING MECHANISM DESCRIPTION: Corrosion of liner CCNPP PA or Task ID: OI-24D. Rev. O. Operating Instructions for the SFP Cooling - Infrequent Qnerations and PE 0-67-2-O-M l
l Criteria 3: Adequate programs must be implemented by the facility operating procedures and )
reviewed by the onsite review committee.
CONFIRMATION / DOCUMENTATION DESCRIPTION / BASIS:
- 1. Does the PA or task have a review / approval process? l YES X NO Basis: The procedure reauires PORC Review and Plant General Manager anoroval after it is submitted by the responsible engineer.
- 2. Does the PA or task have a change / revision process?
O X NO
() YES j Basis: " Preparation and Control of Calvert Cliffs Technical Procedures" PR-1-101. controls the change / revision orocess of this and all other site technical procedures.
O Sheet 10 of _L4
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l Attachment 5 ADEQUATE PROGRAM EVALUATION STRUCTURE / SYSTEM NUMBER: None STRUCTURE NAME: Auxiliary Building STRUCTURAL COMPONENT DESCRIPTION: Caulking and Sealants, Expansion Toints AGING MECHANISM DESCRIFFION: Weathering i
i CCNPP PA or Task ID: STP-F-592-1/2 i
Criteria 1: Adequate programs must ensure mitigation of the effects of age-related.
degradation for the SSCs identified as within the scope of license renewal. :
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! DISCOVERY DESCRIPTION / BASIS:
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l 1. Is there a frequency interval in the PA or Task?
! YES X NO _
O Basis: Both the Unit 1 and Unit 2 procedures are implemented in accordance with the lb t
frequency intervals specified in plant Technical Specification Section 4.7.12.
- 2. Is the frequency interval consistent with industry standards, industry experience, experience unique to Calvert Cliffs, or vendors' recommendations?
l YE X NO Basis: The frequency interval is consistent with that commonly used in the industry for surveillance of fire barrier penetration seals. The frequency interval has been approved in association with the implementation of the CCNPP Appendix R 1 Program. l 1
- 3. Will the PA or Task be applicable to all structural components under the same I component type? l YES X NO_
l l Basis: The procedure is applicable to fire barrier penetration seals including electrical l conduit and cable tray penetration seals, HVAC duct penetration seals, and mechanical pipe penetration seals. The procedure also covers inspection of the fire resistivity of rated walls, ceilings, and floors. Data sheets are provided with the procedure to identify the fire areas requiring inspection.
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I Attachment 5 - Adequate Program Evaluation (continued)
REVISION: 2 DATE: 5/7/% >
l AGING MECHANEM DESCRIFFION: Weatherine --
1 CCNPP PA or Task ID: STP-F-592-1/2 Criteria 2: Adequate programs must contain acceptance criteria against which the need l for corrective action will be evaluated, and ensure that timely corrective action will be taken when these acceptance criteria are not met.
l ASSESSMENT / ANALYSIS / CORRECTIVE ACTION DESCRIFFION/ BASIS:
j 1. Does the PA or Task have an action or alert value or condition parameter to determine l the need for corrective action?
YES X NO _
l l Basis: Acceptance criteria is provided for each type of penetration in Attachment A to l the Unit 1 and Unit 2 procedures. The acceptance criteria provides ihe basis for l determinine the need for corrective action.
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l' 2. Does the action value or condition provide sufficient indication of degradation to ensure that there will not be a functional failure prior to the next PA or Task?
YES X NO _
Basis: The procedures in both units mandate visual inspection of the penetration fire barriers for indications of degradation or damage. The criteria implemented in the Calvert Cliffs penetration fire barrier surveillance procedures will ensure the fire barriers perform their intended functions at all times. This requirement is implemented in accordance with the requirements of Appendix R and CCNPP Technical Specifications.
- 3. Will the action value or condition parameter remain the same during the renewal period
?
YES X N O __
Basis: Since the surveillance procedures and the acceptance criteria in the procedures are to ensure the availability and the reliability of the fire barrier penetration
, seals, this acceptance criteria should not be changed during the renewal period.
t O Sheet 12 of.1_4
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Attachment 5 - Adequate Program Evaluation (continued)
REVISION: 2 DATE: 5/7/%
AGING MECHANISM DESCRIFFION: Weatherine CCNPP PA or Task ID: STP-F-592-1/2 l
l 4. Does the PA or Task ensure that corrective action is taken?
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YES X NO _
Basis: In accordance with Sections 5.4,7.1, and Attachment B of the procedures for both units, any inspection results determined to be unsatisfactory will be reported to l the Shift Supervisor for possible Tech Spec reauired action and to the Fire Protection System Engineer or Fire Protection Engineer for investication and corrective action.
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l 5. Does the PA or Task ensure that the corrective action is appropriately scheduled?
YES X NO _
Basis: All corrective actions must meet reportine requirements specified in Technical
! Specification 4.7.12 of both Units 1 and 2.
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i Sheet 13 of _14 i
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Attachment 5 - Adequate Program Evaluation (continued)
REVISION: 2 DATE: 5/7/96 AGING MECHANISM DESCRIITION: Weathering CCNPP PA or Task ID: STP-F-592-1/2 Criteria 3: Adequate programs must be implemented by the facility operating procedures and reviewed by the onsite review committee.
CONFIRMATION / DOCUMENTATION DESCRIITION/ BASIS:
l 1. Does the PA or Task have a review / approval process?
YES X NO _
Basis: This procedure has a review / approval process per EN-4-104.
- 2. Does the PA or Task have a change / revision process?
YES X NO O
V Basis: @ procedure has a chance / revision process per EN-4-104.- l l
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Sheet 14 of _14
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- Attachment 7
] Walkdown Report - CCNPP i Auxiliary Building November,1994 4
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r l Attachment 7 Walkdown Report - CCNPP Auxiliary Building l November,1994 I
l Date of Walkdown: 11/16/94 l
Participants:
Ken Classon (Bechtel)
{ Summarv: A Walkdown of the CCNPP Auxiliary Buildings was performed to support the Component Evaluation and Program Evaluation of the Auxiliary Building. Selected areas of the interior and l
exterior of the structure were inspected, based on their potential O for degradation due to aging mechanisms. ,
Results: The results of the walkdown/ inspections are included on the 1 following pages. This information was used as input to the Auxiliary Building structure evaluation, as applicable.
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O O O Attachment 7 LCM WALKDOWN INSPECTION - AUXII IARY BUILDING (Page 3 of 5) l APPENDIX AGING MECHANISM CHARACTERISTICS COMMENTS l A Free c-thaw Scaling, cracking, spalling No scaling, cracking, or spalling was observed B Leaching of calcium hydroxide Leachate No leachate was observed l C Aggressive chemicals Spills, discoloration No spills or discoloration was observed D Reaction with aggregates Map cracking No map cracking was observed E Corrosion in embedded Cracking, rust staining, spalling No cracking, rust staining, steel /rebar spalling was observed F Creep NA Creep is not a potential aging mechanism for this structure G Shrinkage NA Shrinkage is not a potential aging mechanism for this structure H Abrasion and cavitation Cracking, spalling Abrasion and cavitation is not a potential aging mechanism for this structure I Cracking of masonry block Cracking No cracking was observed walls J Settlement Cracking No cracking or other evidence of settlement was observed
O O O Attachment 7 LCM WALKDOWN INSPECTION - AUXILIARY BUILDING (Page 4 of 5)
APPENDIX AGING MECHANISM CHARACTERISTICS COMMENTS K Corrosion in steel Rust No rust was observed in the areas of inspection, all structures were satisfactorily coated L Corrosion in liner Cracking, pitting Spent Fuel Pool is filled with water,it was not inspected.
M Corrosion in tendons NA This aging mechanism is not applicable to the Auxiliary Building N Prestressing looses NA This aging mechanism is not applicable to the Auxiliary Building O Weathering Hardening, cracking, loss of Expansion joint material elasticity appeared intact and in satisfactory condition R Elevated Temperatures Heat sources The Unit-1 MSIV room was inspected and no damage due to elevated temperatures was observed ,
S Irradiation Radiation No damage due to radiation was observed. The Auxiliary Building is, typically, not exposed to high levels of radiation
O O O Attachment 7 LCM WALKDOWN INSPECTION - AUXII T ARY BUTI DING (Page 5 of 5) l i APPENDIX AGING MECHANISM CHARACTERISTICS COMMENTS l T Fatigue Vibrating Equipment The Auxiliary Building contains vibrating equipment. fatigue caused by this equipment was considered in the original design. No cracking or spalling of concrete or concrete equipment pads was observed.
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Attachment 8 Attributes in New Program lO i
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l Attachment 8 NITRIBUTES IN NEW PROGRAM REVISION: 2 DATE: May1996 STRUCTURE / SYSTEM NUMBER: None )
STRUCTURE NAME: Auxiliary Building STRUCTURAL COMPONENT DESCRIPTION: Below grade portion of Auxiliary Building walls and concrete foundation mat AGING MECHANISM: Aggressive chemicals APPLICABLE APPENDIX: Appendix C BACKGROUND: The intended functions of the Auxiliary Building wall and the foundation mat is to provide support, protection, and shelter to safety related and non-safety related eauipment inside the Auxiliary Building. Chemical attack is plausible only if the water chemistry of the groundwater has become significantly more ageressive than was originally anticipated.
("' RECOMMENDED ATTRIBUTES: Since degradation of the below grade portion of the Auxiliary Building walls and the foundation mat would have been plausible only if the water chemistry has become more aggressive, the procram proposed will investigate the water chemistry of the ground water. The recommended approaches are:
- 1. Restore the croundwater observation wells installed during initial plant construction for sampling purpose or verify the integrity of the existing piezometers located adiacent to the Auxiliary Buildings.
- 2. Using the water source (s) noted above, a one time verification of the groundwater chemistry shall be performed by securing samples of the underground water for water chemistry testing. If the water chemistry meets original design requirements (Cl ions < 500 ppm, SO4 ions < 1500 ppm,L no further action is necessary. -
- 3. If the water chemistry tests conclude that it is plausible that these concrete components are being degraded by chemical agents, the levels of chemical concentration will need to be assessed to determine the appropriate corrective actions. Additional investigate programs may be required.
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Attachment 8 l l
BASIS: Because of the desien and construction of the concrete Auxiliary Building, and the knowledge of the water chemistry during the desien of the plant (See Specification 6750-C-33L it is unlikely that chemical attack to concrete is a maior l concern.
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(" Attachment 8 ATTRIBUTES IN NEW PROGRAM (continued)
REVISION: 2 DATE: May1996 STRUCTURE / SYSTEM NUMBER: None STRUCTURE NAME: Auxiliary Building STRUCTURAL COMPONENT DESCRIlmON: Below crade portion of Auxiliary Building walls and foundation mat AGING MECHANISM: Corrosion of Embedded Steel /Rebars APPLICABLE APPENDIX: Appendix E BACKGROUND: The intended functions of the Auxiliary Building walls and the foundation mat is to provide support, protection, and shelter to safety related and non-safety related eauipment inside the Auxiliary Building.
Corrosion of below crade portion of Auxiliary Building walls and concrete foundation mat is plausible only if they are exposed to an aggressive environment and on a continual basis, r
I RECOMMENDED ATTRIBUTES: Since degradation of the below grade portion of the Auxiliary Building walls and foundation mat would have been plausible only if the water chemistry has become more corrosive, the procram proposed will investigate the water chemistry of the cround water. The recommended approaches are:
- 1. Restore the groundwater observation wells installed during initial plant construction for sampling purpose or verify the inteerity of the existing piezometers located adiacent to the Auxiliary Buildings.
- 2. Using the water source (s) noted above, a one time verification of the groundwater chemistry shall be performed by securing samples of the l undercround water for water chemistry testing. If the water chemistry l
meets original design reauirements (Cl ions < 500 ppm, SO4 ions < 1500 l ppm,), no further action is necessary.
l l 3. If the water chemistry tests conclude that it is plausible that these concrete components are being degraded by chemical agents, the levels of chemical concentration will need to be assessed to determine the Sheet 4 of 9
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Attachment 8 gppropriate corrective actions. Additionalinvestigate programs may be required.
BASIS: Because of the desien and construction of the concrete Auxiliary Building, and the knowledge of the water chemistry during the design of the plant (See
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Specification 6750-C-33), it is unlikely that chemical attack to concrete is a maior concern.
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. Attachment 8 A'ITRIBUTES IN NEW PROGRAM (continued)
REVISION: 2 DATE: May1996 STRUCTURE / SYSTEM NUMBER: None STRUCTURE NAME: Auxiliary Buildine STRUCTURAL COMPONENT DESCRIPTION: Caulking and Sealants, Expansion Toints AGING MECHANISM: Weathering APPLICABLE APPENDIX: AppendixO BACKGROUND: The intended functions of caulking and sealants and expansion ioints in i
the Auxiliary Building are to provide shelter and protection to safety
- related equipment (including HELB and radiation protection) inside the l' Auxiliary Building. The caulking and sealants have an additional intended function to provide a flood protective barrier for internal
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l floodine events. The caulkine and sealants and expansion ioints are components which are typically replaced on condition. However
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} inspections in the plant revealed that an inspection program was required to adequately manage the acing of these components.
Note: The caulking and scalants and expansion icints which reauire a new program to manage their agine do not perform the intended function of a fire barrier. Caulking and sealants and expansion joints which perform a fire barrier function are managed under an existing ;
program.
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- RECOMMENDED l ATTRIBUTES. The management program for the caulking and sealants and expansion ioints is recommended to be developed in association with the resolution i to Issue Report IR1995-01698. The program must manace the azine of
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the caulking and sealants and expansion ioints in the Auxiliarv Buildine l
which support intended functions of the structure. The recommended l l
approaches are:
l
- 1. Identify all non-Appendix R caulking and sealants and expansion ioint locations that support the structure's intended functions.
- 2. Develop an inspection and maintenance program which will identify
, degradation and ensure corrective action is taken before the component Sheet 6 of 9 l
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. _ . . - - - . . . -. . . - - . - - . _ ~ . . - _ - - _. - -
^g Attachment 8 loses the ability to perform its intended function. The program should concentrate on caulking and sealants and expansion ioints located in exterior walls and in interior walls and floors where HELB and flooding functions areperformed.
BASIS: The management program for the caulking and sealants and expansion
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i ioints is recommendeil to be developed in association with the resolution !
to Issue Report IR1995-01698. The issue report identified ioints in the
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Auxiliary Building which showed siens of derradation. Resolution of this issue report will ensure development of an aging management program for caulking and sealants and expansion ioints in the Auxiliary Building such that these components will be able to perform their intended functions both during the current license period and the period of extended operations.
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Sheet 7 of 9
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O Attachment 8 l A'ITRIBUTES IN NEW PROGRAM (continued) i REVISION: 2 DATE: May1996 STRUCTURE / SYSTEM NUMBER: None l
STRUCTURE NAME: Auxiliary Buildine E
STRUCTURAL COMPONENT DESCRIPTION: Non-accessible ctructural steel l
l AGING MECHANISM: Corrosion of Steel l .
l APPLICABLE APPENDIX: Appendix K BACKGROUND: The intended functions of the Auxiliary Building steel structures is to provide support, protection, and shelter to safety related and non-safety related eauipment inside the Auxiliary Buildine. Corrosion of steelis
! plausible only if their coatines are degraded and if they are exposed to an
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L ageressive environment and on a condnual basis. Aging management of degraded coating conditions on accessible structural steel in the Auxiliary Building is accomplished through the combination of existine fl plant programs. However, structural steel components not readily O
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' ccessible reauire additional aging management.
a RECOMMENDED A'ITRIBUTES: An age related degradation inspection (ARDI) program as described in the BGE Integrated Plant Assessment Methodology should be implemented to address corrosion of non-accessible structural steel components which support the intended functions of the Auxiliary Building. The ARDI program must consist of the following:
- 1. Identification of non-accessible locations.
- 2. Selection of renresentative structural steel comoonents for insnection.
- 3. Develooment of an insoection samole size.
- 4. Use of Anoropriate insocction techniaues.
l S. Requirements for reoorting of results and corrective actions if aging concerns are identified.
l Sheet 8 of 9
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\ Attachment 8 Y
BASIS: The ARDI Program _ will ensure that degraded conditions due to corrosion of steel are identified and corrected such that non-accessible structural steel comoonents of the Auxiliarv Building will be canable of nerforming their intended functions under all design conditions reauired by the current licensing basit l
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Sheet 9 of 9 l
{
G APPENDIX A- FREEZE-THAW Q -.
1 1.0 MECilANISM DESCRII'rION 2 Repeated cycles of freezing and thawing can alter both the mechanical properties and physical form of the concrete, thus affecting the structuralintegrity of the component.
The freeze-thaw phenomenon occurs when water freezes within the concrete's pores, creating hydraulic pressure. This pressure either increases the size of the cavity or forces water out of the cavity into surrounding voids. l Freeze-thaw damage is characterized by scaling, cracking, and spalling. Scaling or surface flaking occurs in the presence of moisture and is aggravated by the use of deicing salts. Cracks or spalling occurs when voids are already filled with water, and freezing causes pressure to increase. In extreme cases of freeze-thaw damage, the cover over reinforcing steel is reduced, and the reinforcing steel is eventually exposed to accelerated corrosion. Concrete is vulnerable to the expansive effects of the resulting corrosion products, thereby weakening the concrete's resistance to further attack by aggressive environments.
To minimize the adverse effects of freeze-thaw, three factors must be considered in the design and placement of concrete: 2 Q -
The cement paste must have an entrained air system with an appropriate V void spacing factor.
The aggregate must be of a sufficiently high quality to resist scaling.
The in-place concrete must be allowed to mature sufficiently before exposure to cyclic freezing and thawing.
As shown in Figure A-1, the optimal air content range extends from 3 to 6 percent based on the nominal maximum size of coarse aggregate. 3 j i
2.0 EVALUATION 2.1 Conditions According to Specification ASTM C33-82, " Standard Specification for Concrete Aggregates,"4 the CCNPP site is located in the geographic region subject to severe weathering conditions. As stated in CCNPP's " Civil and Structural Design Criteria,"5 the frost penetration depth is 20 to 22 inches.
r3 Sf7N6 a A-1 Revision 2
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i(~ Freeze-Thaw l( )
l 2.2 Potential Aging Mechanism Determination l Freeze-thaw is a potential aging mechanism for the following concrete structural l components of the Auxiliary Building because they are exposed to outside cold l
weather:
Concrete walls above the j frostline(which is 2 l feet below grade) LR functions LR-S1,2,4,5,6,7 where:
LR-S1: Provides structural and/or functional support (s) for safety-related equipment.
LR-S2: Provides shelter / protection for safety-related equipment.
LR-S4: Serves as a missile barrier (internal or external).
LR-S5: Provides structural and/or functional support (s) for non-safety-p related equipment whose faliure could directly prevent satisfactory accomplishment of any of the required safety-related func: ions.
f LR-S6: Provides flood protection barrier (internal flooding event).
LR-S7: Provides rated fire barriers to confine or retard a fire from ,
spreading to or from adjacent areas of the plant.
Other concrete structural components are either below the frost line or are located inside the Auxiliary Building. (Note: The concrete roof of the Auxiliary Building is protected by a built-up roofing system and portions of the Auxiliary Building walls are protected with siding). Therefore, freeze-thaw is not a potential aging mechanism for all other structural components.
2.3 Impact on Intended Functions If the effects of freeze-thaw were not considered in the original design or are allowed to degrade the above structural components unmitigated for an extended period of time, this aging mechanism could affect all the intended LR functions of components )
listed in Section 2.2. j l
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5/786 m A-2 Revision 2
Freeze-Thaw l
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2.4 Design and Construction Considerations l l
CCNPP concrete design specification No. 6750-C-96 specifies l 9.3.1 The Portland arnent concrete furnished, unless otherwise speaped herein, shall conforrn to ASTM C-94 Speapcationfor Ready Mix Concrete, ACI 318-63 Building Code Requirernentsfor Reinforud Concrete, ACI 301-66 Standard Speapcationsfor Structural Concrete for Building, and ACI Manual of Concrete inspection.
10.1.2.2 Allaggregate shall conform to ASTM Designation C33.
Section 10.1.16 of ASTM Designation C33-67 specifies that-Procedures for making freezing and thawing tests of concrete are described in ASTM Method :90, " Test for Resistance of Concrete .
Specimens to Rapid Freezing and Thawing in Water," and in ASTM Method C291, *Resistana of Concrete Specimens to Rapid Freezing in Air and Thawing in Water."
Both ASTM Methods C290 and C291 cover the method for determining the resistance of concrete specimens to rapidly repeated cycles of freezing and thawing in the :
l laboratory.
Design specification No. 6750-C-9 for CCNPP also specifies: l 10.4.2.1 The Subcontractor shall specify the air entraining agent he proposes to use. It shall be in accordance with ASTM C-260, capable of entraining 3-S% air, be completely water soluble, and be cornpletely dissolved when it enters the batch. The Subcontractor shallgive 30 days i i
advance notice of the type ofAEA he proposes to use.
ACI 3187 and its relevant ACI standards and ASTM specifications provide the physical propenty requirements of aggregate and aie-entraining admixtures, chemical -
and physical requirements of air-entraining cements, and proportioning of concrete including containing entrained air to maximize the concrete resistance to freeze. thaw j action.
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Freeze-Thaw
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2.5 Plausibility Determination l Based on the discussion on Section 2.4, concrete used for the walls of the Auxiliary Building wall were designed and constructed in accordance with the requirements j specified in AQ-318 and its relevant ACI standards and ASTM specifications. Those l requirements satisfy the attributes discussed in Section 1.0 that maximize concrete's l resistance to freeze-thaw action. A walkdown of the Unit 1 contairunent (located l adjacent to the Auxiliary Bu3 ding and using the same concrete specification) conducted during 19928, documented no evidence of damage from freeze-thaw.
Additionally, a walkdown in 1994' observed no traces of freeze-thaw damage on the exposed exterior walls of the Unit-2 Auxiliary Building. Therefore, freeze-thaw is not a plausible aging mechanism for the walls of the Auxiliary Building.
2.6 Existing Programs There are no existing programs at CCNPP that are designed specifically to identify or l
to repair freeze-thaw damage. Since freeze-thaw is not a plausible aging mechanism that could degrade the Auxiliary Building structural components, no management program is necessary.
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3.0 CONCLUSION
l The CCNPP site is located in the geographic region subject to severc weathering .
conditions. Although freeze-thaw cycles can degrade concrete components that are )
exposed to cold temperatures and in constant contact with moisture, the Auxiliary .
Building walls were constructed with concrete designed to maximize its resistance to I freeze-thaw cycles. A walkdown inspection of the Unit 1 containment structure I performed in 1992 found no indication of freeze-thaw effect on the concrete structure. Additionally, a walkdown inspection of the exterior walls of the Unit 2 Auxiliary Building in 1994' found no indication of freeze-thaw damage. Since the Auxiliary Building is adjacent to the containment and fabricated using the same concrete specification, these findings substantiated further the conclusion that freeze-thaw is not a plausible aging mechanism for the structural components of the Auxilhry Building.
4.0 RECOMMENDATION Freeze-thaw is not a plausible aging mechanism for any concrete structural components of the Auxiliary Building. No further evaluation or recommendation is l required.
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l /Q Freeze-Thaw V
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5.0 REFERENCES
l
- 1. "Cass I Structures License Renewal Industry Report," EPRI's Project RP- l l 2643-27, December 1991.
- 2. Mather, B., "How to Make Concrete that Will Be Immune to the Effects of
( Freezing and Thawing," AG Fall Convention, San Diego, November 1989.
- 3. Troxell, G. E., Davis, H. E., and Kelly, J. W., Composition and Properties of Concrete, Second Edition, McGraw-Hill,1968.
- 4. " Standard Specification for Concrete Aggregates," Ameri.an Society of Testing and Materials, ASTM C33-82.
- 5. Qvil and Structual Design Criteria for Calvert Giffs Nucle ar Power Plant Unit No. I and 2, by Bechtel Power Corporation, Revisioi 0, August 2, i
1991.
l
- 6. " Specification for Furnishing and Delivery of Concrete - Calvert Cliffs i Nuclear Power Plant Unit No.1 and 2," CCNPP's Design Specification No.
l em 6750-C-9, Revision 8, April 1970.
- 7. " Building Code Requirements for Reinforced Concrete," American Concrete Institute, AG 318-63.
- 8. " Examination of the Unit 1 Containment Structure - Calvert Giffs Nuclear l Power Plant," August 1992.
- 9. Walkdown - Auxiliary Building, November,1994.
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Freeze-Thaw O
I I i 4 Water.coment ratio, slump, and sand perumatage held
- 11/2in. W= size agregaan.
320 m 4#00 '
- 7. I t w arar c m e g too j :: %'N %%
WW poo B g
'f N .I I / 1400 i
';tooj L
200 4 , 3 1000 150 0 J n
0 5 m a N O ^ ' - ' ' -
Figure A-1 Effects of Air Content on Durability, Compressive Strength, and Required Water Content of Concrete (Source: Reference 3)
Sf786 a A-6 Revision 2
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i
]v APPENDIX B - LEACHING OF CALCIUM HYDROXIDE i 1.0 MECHANISM DESCRil'flONI Water, either from rain or melting snow, that contains small amotmts of calcium ions can readily dissolve calcium compounds in concrete when it passes through cracks, inadequately prepared construction joints, or areas inadequately consolidated during placing. The most readily soluble calcium compound is calcium hydroxide (lime).
l The agg.essiveness or affinity of water to teach calcium hydroxide depends on its dissolved salt content and its temperature. Since leaching occurs when water passes through the concrete, structures that are subject to flowing liquid, ponding, or hydraulic pressure are more susceptible to degradation by leaching than those structures that water merely passes over, leaching of calcium hydroxide is visible on concrete surfaces that have dried. The leachate is almost colorless until carbon dioxide is absorbed and the material dries as a white deposit. The white deposit is a product of water, free lime from the concrete, and carbon dioxide that has been absorbed from the air.
When calcium hydroxide is leached away, other cementitious constituents become exposed to chemical decomposition, eventually leaving behind silica and alumina gels with little or no strength.2 Iraching over a long period of time increases the porosity and permeability of concrete, making it more susceptible to other forms of p aggressive attack and reducing the strength of concrete. leaching also lowers the pH Q of concrete and threatens the integrity of the exterior protective oxide film of rebar.
Resistance to leaching and efflorescence can be enhanced by using concrete with low I permeability. A dense concrete with a suitable cement content that has been well cured is less susceptible to calcium hydroxide loss from percolating water because of its low permeability and low absorption rate. The design attributes to enhance water-tightness include low water-to-cement ratio, smaller coarse aggregate, long curing periods, entrained air, and thorough consolidation? Figures B-1 and B-2 show the impact on permeability due to water-txement ratio, aggregate size, and curing time.
2.0 EVALUATION 2.1 Conditions The exterior walls of the Auxiliary Building not protected by siding are exposed to the outside environment and are expected to have rainwater passing over the surface. The Auxiliary Building concrete roof is provided with a built-up roofing system with a drainage system to prevent ponding and, therefore, does not pose a threat to Iraching of CGcium Hydroxide. The Auxiliary Building foundation l (concrete mat) is in ccv.itact with underground water. A permanent dewatering l system was instalW. during construction to maintain a stable groundwater table at l El.10'-0", which is the above the elevation of the Auxiliary Building foundation mat p (top of mat elevation varies from El. +3'-0" to El. -15'-0").
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SW96 x B-1 Revision 2
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I Leaching of Calcium Hydroxide i
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l 2.2 Potential Aging Mechanism Determination ;
leaching of calcium hydroxide is a potential aging mechanism for the following structural components of the Auxiliary Building because they could be exposed to flowing liquid, ponding, or hydraulic pressure- !
i
+ Exterior ConcmteWalls M furvtions M-S-1,2,4,5,6,7 ;
i
+ Concrete Foundation Mat a functions 2-S-1,5 l
where:
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I M-S-1: Provides structural and/or functional support (s) for safety-related equipment.
! I M-S-2: Provides shelter / protection for safety-related equipment. i l M-S-4: Serves as a missile barrier (internal or external). l l
M-S-5: Provides structural and/or functional support (s) for non-safety- l related equipment whose failure could directly prevent satisfactory '
accomplishment of any of the required safety-related functions.
l l G-S-6: Provides flood protection barner (internal floodmg event). ;
i 1 U -S-7: Provides rated fire barriers to confine or retard a fire from spreading to or from adjacent areas of the plant.
Imaching of calcium hydroxide is not a potential aging mechanism for other
, structural components of the Auxiliary Building because they are inside the l Auxiliary Building. Additionally, the concrete roof slabs are protected by a built-up l roofing system with its own drainage system and portions of the exterior concrete l walls are protected by siding.
2.3 Impact on Intended Functions if the effects of leaching of calcium hydroxide were not considered in the original design or are allowed to degrade the above structural components unmitigated for ,
an extended period of time, this aging mechanism could affect all the intended 1 functions of components listed in Section 2.2.
2.4 Design and Construction Considerations
- leaching attack can be minmuzed by providing a low-permer.bility concrete mix
! design during construction. CCNPP concrete design specification No. 675K-94
)p 6Pecifies:
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i Leaching of Calcium Hydroxide 9.3.1 The Portland arnent concrete furnished, unless othenoise speafed herein, shall conform to ASTM C-94 Speapcation for Ready Mix Concrete, ACI318-63 Building Code Requirementsfor Reinforced Concrete, ACI 301-66 Standard Speapcationsfor Structural Concrete for Building, and ACI Manual of Concrete Inspection.
, 12.1 Concrete Quality l
12.1.1.1 Portland cement shall conform to ASTM Designation C-94-67, Alternate No.1 and ACI301-66.
I 12.1.2.1 Concrete shall rneet thefollowing requirements: .
Nominal 28-Day Slump at Slump Maximum Class Strength Point of Tolerance Aggregate lise andlocation
[ (psi) Placement (in.) Size (in.)
B-1 3,000 3 t% .V4 in. Structural Concrrle Wall & Stabs less than 12' thick & Congested Rebar B-2 3,000 3 1% 1-1)2 in. Turbine Pedestal &otler Structural Q Concrete l B Grout 3,000 - - #4 Construction Joints G1 4,000 3 t% 3/4 in. Walls & Slabsless than 12" thick &
Congested Rebar i
l G2 4,000 2 t% 1-% in. Contamment Base Slab and Otler Structural Concrete l
l CGrout 4,000 - - N4 Construction joints l Dry Pack 4,000 0 - N4 As Directed j 4
t
? Tre:nie 4,000 6 -
3/4 in. As Directed Concrrte l
l 12.1.5 Mix Design ;
l 12.1.5.1 The Constructor shall retain an approved Testing laboratory, at his own cost, to design and test initial concrete mixes. The initial mixes shall be designed in accordance with ACI Standards 613 and 301 to produce a required strength of15 percent over speafed strengthfor reinforced concrete at 28 days and 25 percent over speafed strengthfor post-tensioned concrete at 28 daysfor each class of concrete with slump and unaximum sizes of aggregate as speafed in the Cassifcation Table (Section 12.1.2).
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5f7N6 m B-3 Revision 2 \
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i-Leaching of Calcium Hydroxide l
l 12.1.5.2 The Constructor shallfurnish the Subcontractor with mix designs one month prior to the manufacture of concrete. Furnishing
\ mix designs shall not relieve the Subcontractor of his responsibilityfor compliance with the provssions of the Speafcation. Where necessary,
~ the Constructor shall increase or decrease cement factors as deemed l necessary pr design mixes using statistical methods desenbed in the ACI 214-65 for the particular class of concrete. An increase in the l water-cement ratio of a mix design or a decrease in its cement quantity shall constitute a new mix design and the provisim ofSection 12.1.5.1 of this Speafcation shall apply. Calcium chloride shall not be used.
l 2.5 Plausibility Determination Based on the discussion in Section 2.1, the Auxiliary Building exterior walls and [
j foundation mat are exposed to water passing over the surface. The Auxiliary 4 l Building foundation mat is located below the designed underground water table and
! - may be subjected to some hydraulic pressure. However, as discussed in Section 2.4, l concrete used for the Auxiliary Building was designed in accordance with ACI 3185 j l and its relevant ACI standards and ASTM specincations to maximize resistance to ,
leaching of calcium hydroxide. A walkdown6 in 1992 observed only slight traces of :
leaching on the containment dome and wall and were judged to have no adverse i impact on the integrity of these components. Since the Auxiliary Building is adjacent to the contamment and is fabricated from the same concrete specification, this is a good indication that the Auxthary Building exterior walls and foundation mat also '
have had no adverse impact on their integrity, due to leaching of calcium hydroxides.
j Additionally, a walkdown in 19948 observed no traces of leaching on the exposed l exterior walls of the Unit-2 Auxiliary Building. Therefore, leaching of calcium hydroxide is not a plausible aging mechanism for the Auxiliary Building exterior walls or foundation mat.
- 2.6 Existing Programs l There are no existing programs at CCNPP that are designed specifically to identify or to repair damage to concrete due to leaching of calcium hydroxide. Since leaching of l calcium hydroxide is not a plausible aging mechanism that could degrade the Auxiliary Building structural components, no management program is necessary.
l l
3.0 CONCLUSION
l The Auxiliary Building foundation mat and a portion of the exterior walls (those not l l covered by protective siding) are exposed to water, however, no ponding or l hydraulic pressure will form to leach the calcium hydroxide. Although the Auxiliary Building foundation mat could be subjected to hydraulic pressure due to underground water, the concrete mix was designed for low permeability and high compressive strength which provide the best protection against leaching. l i
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! Leaching of Calcium Hydroxide l
This conclusion is supported by a 1992 walkdown inspection 6 during which only minor traces of leaching marks were detected in various areas of the containment ,
dome and wall. These indications were judged to have no impact on containment '
integrity during the 10S evaluation of the containment structural components (Note:
The Auxdiary Building is immediately adjacent to the contamment and is fabricated ,
using the same concrete specification). Additionally, a walkdown in 19948 observed no traces of leaching on the exposed exterior walls of the Unit-2 Auxdiary Building. I
- Therefore, leaching of calcium hydroxide is not a plausible aging mechanism for any concrete structural components of the Auxthary Building.
i 4.0 RECOMMENDATION Imaching of calcium hydroxide is not a plausible aging mechanism for any concrete structural components of the Auxiliary Building. No further evaluation or recommendation is required.
5.0 REFERENCES
I l- 1. " Class I Structures License Renewal Industry Report," EPRI's Project RP-
'e 2643-27, December 1991.
- 2. '1roxell, G. E., Davis, H. E., and Kelly, J. W., Composition and Properties of Concrete, Second Edition, McGraw Hill,1968. -
j
- 3. " Guide to Durable Concrete," American Concrete Institute, ACI-201.2R-67.
I 4. " Specification for Furnishing and Delivery of Concrete - Calvert Cliffs Nuclear Power Plant Unit No.1 and 2," CCNPP's Design Specification No.
6750-C-9, Revision 8, April 1970.
i
( 5. " Building Code Requirements for Reinforced Concrete," American ConcreteInstitute, ACI318-63.
- 6. " Examination of the Unit 1 Containment Structure - Calvert Cliffs Nuclear Power Plant," August 1992.
- 7. Concrete Manual, Eighth Edition, U.S. Department of the Interior,1975.
- 8. Walkdown- Auxiliary Building, November,1994.
i 5!78 6 E B-5 Revision 2
( Leaching of Calcium Hydroxide i
I
!' '" n.cem ..
r::::::mypy.:: -- r [j 1- -r.::st::,.,e
- 120 F*84884*
fff 1 11n j 100 l 9C
- 8l
) I b ** 5 $ *f
- 70
- t
- so // /
i
!O - // /
I I) e
/
/ 1 9 40 i
/ // </
/f l / //
j
,o
,, m 1
! o o.4 o.s o.s 0.7 o.8 o.s WATER - CEMENT RATIO BY WEIGHT Figure B-1 Relationship Between Coefficient of Permeability and Water-to-Cement Ratio (Source: Reference 7) 50/96 m B-6 Revision 2
l Leaching of Calcium Hydroxide a.s l
r a.: \ '
me. ir a.s reer se --a:sesen.elen.
Peenwas: 30sei s.s l
l
,, wx.seo l ,
i e44 0- i o e 3 7 s4 . as e ra.s e ie e ,ine e n.e.ye l
i l
Figure B-2
! Effects of Curing Period on Permeability
- (Source: Reference 2) !
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v APPENDIX C - AGGRESSIVE CHEMICALS i
1.0 MECHANISM DESCRII7 TION 1 ,
l Concrete, being highly alkaline (pH > 12.5), is vulnerable to degradation by strong acids. Acid attack can increase porosity and permeability of concrete, reduce its alkahne nature at the surface of the attack, reduce strength, and l render the concrete subject to further deterioration. Portland cement I concrete is not acid-resistant, although varymg degrees of resistance can be l achieved depending on the materials used and the attention to placing, consolidating, and curmg. No Portland cement concrete, regardless of its I composition, will withstand exposure to highly acidic fluids for long i periods. i Below grade, sulfate solutions of sodium, potassium, and magnesium sometimes found in groundwater may attack concrete, often in combination j' with chlorides. The exposed surfaces of structures located near industrial plants are vulnerable to industrial pollution from the sulfur-based acid rain and are subject to deterioration. Sulfate attack produces significant expansive stresses within the concrete, leading to cracking, spalling, and I I
strength loss. Once established, these conditions allow further exposure to
(])
( aggressive chemicals. Groundwater chemicals can also damage foundation I concrete. A dense concrete with low permeability may provide an '
acceptable degree of protection against mild acid attack. Any factors that tend to improve the compressive strength of the concrete will have a beneficial effect on low permeability. Therefore, the better the quality of the constituent material, the less permeable the concrete. Low water-txement ratio, smaller aggregate, long curing period, entrained air, and thorough consolidation all contribute to watertightness. l l
Concrete thus constructed has a low permeability and effective protection against sulfate and chloride attack. Mmimum degradation threshold limits !
for concrete have been established at 500 ppm chloride or 1,500 ppm sulfates.
The use of an appropriate cement type (e.g., ASTM C150, Type II) and l pozzolan (e.g., fly ash) also increases sulfate resistance.
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5/7/96 a C-1 Revision 2
P l, Aggressive Chemicals
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l 2.0 EVALUATION
- 2.1 Conditions The only significant inventory of aggressive chemicals stored inside the l
Auxiliary Building is borated water, and it is prunarily in safety-related systems such as the chemical volume control system. Because of the safety significance of these systems, undetected leakages of borated water for an extended period of time cannot occur. Additionally, the borated water is stored in tanks located in the Protected Area of the Auxiliary Building, l which means that Health Physics technicians are en duty in these areas 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> a day. Therefore, the Auxihary Building's interior surface and all internal structural components are not exposed to the risk of aggressive ;
chemicals.
i
- There is no heavy industry near the CCNPP site that could release l aggressive chemicals to the atmosphere. However the above-grade portion l of the Auxiliary Building exterior walls are exposed to an environment l containing chloride ions due to the Auxiliary Building's proximity to the Chesapeake Bay.
I The outside, below-grade surface of the Auxthary Building foundation mat i and walls are exposed to soil and groundwater. The potential for degradation by aggressive chemicals depends on the quality of concrete and the chemical composition of the groundwater. Although a waterproof -
membrane was installed against the external surfaces of the concrete during construction 6, the minimum life expectancy of the membrane is only five ,
years. '
2.2 Potential Aging Mechanism Determination Attack by aggressive chemicals is a potential aging mechanism for the following concrete structural components of Auxiliary Building because they are exposed to outside environment:
- Exterior concrete walls LR functions LR-S-1,2,4,5,6,7
+ Concrete foundation mat LR functions LR-S-1,5 j
l where:
- o LR-S-1
- Provides structural and/or functional support (s) for safety-related equipment.
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5f786 m C-2 Revision 2 l
-. . .. = - - . . - - . - - .- - - . - _ .. _ -_ . .
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i Aggressive Chemicals LR-S2: Provides shelter / protection for saftty-related equipment.
LR-S-4: Serves as a missile barrier (intemal or external).
LR-S-5: Provides structural and/or functional support (s) for non- ,
safety-related equipment whose failure could directly prevent i satisfactory accomplishment of any of the required safety-related
- functions. 3 LR-S-6
- Provides flood protection barrier (internal flooding event). :
LR-S-7: Provides rated fire barriers to confine or retard a fire from spreading to or from adjacent areas of the plant. ,
Other concrete structural components are located inside the Auxdiary ,
Building; therefore, attack by aggressive chemicals is not a potential aging !
mechanism. Additionally, the concrete roof slabs are protected by a built-up ,
roofing system with its own drainage system and a portion of the exterior !
l concrete walls are protected by siding.
2.3 - Impact on Intended Functions if the effects of attack by aggressive chemicals were not considered in the i original design or are allowed to degrade the above structural components unmitigated for an extended period of time, this aging mechanism could affect all the intended functions of components listed in Sedion 2.2.
l I 2.4 Design and Construction Considerations The Auxiliary Building was constructed with concrete that complies with j CCNPP's design specification No. 6750-C-92 to assure low permeability, i
2.5 Plausibility Determination Based on the discussion in Sections 2.1 and 2.4, attack by aggressive chemicals is not a plausible aging mechanism for the Auxiliary Building
! exterior walls above grade. Additionally, a walkdown in 10944 observed no
( traces of aggressive chemical damage on the exposed exterior walls of the
, Unit-2 Auxiliary Building.
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l Aggressive Chemicals lq l
'%.)
Because chemical contents of groundwater are not known, attack by aggressive chemicals to the below-grade portion of the Auxiliary Building exterior concrete walls and mat is a plausible aging mechanism.
2.6 Existing Programs There are no existing programs at CCNPP that are designed specifically to I
identify or to repair damage to concrete due to aggressive chemicals. Since attack by aggressive chemicals is not a plausible aging mechanism for all ;
concrete components inside the Auxthary Building and the Auxthary {
Building exterior walls above grade, no management program is needed for ;
these components. ;
3.0 CONCLUSION
l l
Attack by aggressive chemicals is not plausible for the Auxthary Building exterior walls above grade because concrete with low permeability, which minimizes concrete cracking, was used in construction of the Auxiliary I
O Building walls. Additionally, there is no heavy industry near the CCNPP V site to release aggressive chemicals. Attack by aggressive chemicals is also not plausible for concrete components inside the Auxiliary Building because l excessive leakages of stored aggressive. chemicals inside the Aux 1hary i Building cannot occur. I The below-grade portion of the Auxiliary Building and the foundation mat are exposed to groundwater. Because the quality of groundwater is not known, degradation due to aggressive chemicals is plausible.
4.0 RECOMMENDATION During initial plant construction, groundwater observation wells were installed to monitor the fluctuation of the groundwater table, and samples were taken for groundwater quality testing.S These wells have been taken out of service, however, several piezometers in the area of the Auxiliary Building are still in place s. It is recommended that a program be developed to investigate the groundwater chemistry using the existing piezometers.
This data can be used to determine if it is plausible that aggressive chemicals have degraded the exterior surface of the Auxiliary Building structure below grade.
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5/7/96 m C-4 Revision 2
.. . . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . . _ _ . _ _ _ ~ _ _ . _ . . . _ ._ _.
A Aggressive Chemicals V
l
5.0 REFERENCES
- 1. " Class I Structures License Renewal Industry Report," EPRI's Project RP-2643-27, December 1991.
l l 2. " Specification for Furnishing and Delivery of Concrete - Calvert i Cliffs Nuclear Power Plant Unit No.1 and 2," CCNPPs Design
~ SpecificationNo.6750-C-9, Revision 8, April 1970.
- 3. " Specification for Furnishing and. Installation of Piezometers -
Calvert Cliffs Nuclear Power Plant Unit No.1 and 2," CCNPP's Design Specification No. 6750-C-23E, Revision 0, November 1973.
l
- 4. Walkdown - Auxiliary Building, November,1994.
- 5. Drawing 61-523-E, Sheet 1, " Yard Piping Plan - Sheet 1", Rev. 27.
l i
- 6. " Specification for Furnishing and Delivering Waterproof l Membrane - Calvert Cliffs Nuclear Power Plant Unit No.1 and 2," l I
P's Design Specification No. 6750-C-33, Revision 0, December l
l !
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5f7&6 a C-5 Revision 2 l
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'V APPENDIX D - REACTIONS WITH AGGREGATES l I
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l 1.0 MECHANISM DESCRII'rIONI i Certain mineral constituents of all aggregates react with chemical !
compounds that compose the Portland cement, most notably alkalis. Alkalis may also be introduced from admixtures, salt-contaminated aggregates, and penetration by seawater or solutions of deicing salt. However, it is only when the expansive reaction products become extensive and cause cracking of concrete that aggregate reactivity is considered a deleterious reaction.
Three principal deleterious reactions between aggregates and alkalis have been identified as alkali-aggregate, cement-aggregate, and expansive alkali-carbonate reactions.
Alkali-aggregate reaction, more properly designated as alkali-silica reaction, involves aggregates that contain silica and alkaline solutions. All silica minerals have the potential to react with alkaline solution, but the degree of reaction and ultimate damage incurred can vary significantly. Alkali-silica reaction can cause expansion and severe cracking of concrete structures.
Reactive materials in the presence of potassium, sodium, and calcium oxides
[V] derived from the cement react to form solids, which can expand upon exposure to water.
Cement-aggregate reaction occurs when the alkabs in cement and some siliceous constituents of the aggregates react. This reaction is complicated by environmental conditions that produce high concrete shnnkage and alkali concentrations on the surface due to drying. Sand-gravel aggregates from some river systems in the Midwestern United States have been involved in deteriorated concrete attributable to this reaction.
Expansive alkali-carbonate reaction occurs between certain carbonate aggregates and alkalis, and produces expansion and cracking. Certain limestone aggregates, usually dolomitic, have been reported as reactive.
l Aggregates that react with alkalis can cause expansion of varying severity, j even to the extent of producing cracking of the concrete and resulting loss of j strength and durability if the expansion is severe. The cracking is irregular l and has been referred to as map cracking. ]
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5f7D6 a D-1 Revision 2 I
l l IN Reactions with Aggregates i
G Moisture must be available for chemical reactions between aggregates and alkalis to occur. Consequently, areas that are either consistently wet or alternately wet and dry are susceptible to deterioration given the presence of potentially reactive aggregat s.
The deleterious effects of reactive aggregates are best avoided by using aggregates from sources that have a proven record of service. If such records are unavailable, aggregates should be examined petrographically to identify l potentially reactive constituents. Chemical reactions of aggregates for both fast and slow reaction rates were recognized as early as 1940. The method to identify the reactive constituents in concrete aggregates was first published in ASTM C-289, " Potential Reactivity of Aggregates (Chemical Method)"2 and ASTM C-295, " Petrographic Examination of Aggregates for Concrete"3 in 1952 and 1954, respectively. Both standards provide guidance for selecting aggregates and cements to avoid alkali-aggregate reactions.
l 2.0 EVALUATION O.
l i ) 2.1 Conditions
! v The aggregates used in the concrete of the CCNPP Auxiliary Building came from sites in Charles County, Maryland 4, which is not in the geographic
- regions known to yield aggregates suspected of or known to cause aggregate reaction.
2.2 Potential Aging Mechanism Determination l Reaction with aggregates is a potential aging mechanism for the following concrete structural components if reactive aggregates were used in the j concrete structure construction: l l
+ Concrete columns LR functions LR-S1,5 I
l
+ Concrete beams LR functions LR-S-1,5 i
+ Ground floor slab and i equipment pads LR functions LR-S-1,5 i + Elevated floor slabs LR functions LR-S-1,2,5,7 p + RoofSlabs LR functions LR-S-2,4 V
Srm6 n D-2 Revision 2 i
. - -._-- .. .-- -. . -. . ~ ._ .-
(~ Reactions with Aggregates
+ Concrete walls LR functions LR-S-1,2,4,5,6,7 l
+ Concrete foundation LR functions LR-S 1,5 l
mat b ,
+ Fluid retauung walls 3
& slabs LR functions LR-S-1 where:
1 l' LR-S-1: Provides structural and/or functional support (s) for' safety-l related equipment.
LR-S-2: Provides shelter / protection for safety-related equipment. .
j LR-S-4: Serves as a missile barrier (internal or external).
LR-S5: Provides structural and/or functional support (s) for non-safety-related equipment whose failure could directly prevent O, satisfactory accomplishment of any of the required safety-related functions.
LR-S6: Provides flood protection barrier (internal flooding event).
LR-S-7: Provides rated fire barriers to confine or retard a fire from spreading to or from adjacent areas of the plant.
2.3 Impact on Intended Functions If the effects of reaction with aggregates were not considered in the original design or are aPowed to degrade the above structural components unmitigated for an extended period of time, this aging mechanism could affect all the intended functions of components listed in Section 2.2.
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.5/7/96 m D-3 Revision 2
-. -..- .. .. - - _ - . . ~ . - . _ . . . - . _ -
l t
.(] Reactions with Aggregates ,
Q/ \
2.4 Design and Construction Considerations All aggregates used in construction of the CCNPP Auxiliary Building structure were investigated, tested, and examined based on the following j specifications:
CCNPP's design specification No. 6750-C-95 specifies:
10.1.1.1 Cernent shall be Portland ament, Type II conforming to ASTM Designation C-150, . . . The ament shall not contain \
more than 0.60 perxnt by neight ofalkalies aniculated as Na2O l
plus 0.658 K:O. Only one brand ofxment shall be usedfor all {
ucrk. . . . ,
l 15.2.3.1 The Bidder, at his expense, shall retain an approied independent testing laboratory to sample and test aggregates and the aggregate sourx in accordana toith rnethods as specifsed in ASTM Designation C-33.
Acxplability of aggregate and sourx shall be based on the following ASTM tests:
m/
l Method oftest ASTMDesignation PotentialReactivity C-289 15.2.3.4 Upon award of the subcontract, the Subcontractor shall subrnit for petrographic analysis, in accordance with ASTM Designation C-295, a 5-pound sample of quarried rnalerial, or if alluvial, 2-1/2 pounds each of sand and coarse material which has been urtified as sampled at the proposed aggregate sourx by an approzed testing laboratory.
15.2.3.6 . . . Aggregates will be tested during the progress of the work. . . .Thefollowing user tests will be performed on eiery 4,000 tons ofaggregates delitered to thejobsite:
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l i l l Reactions with Aggregates l
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Method oftest ASTMDesignation PotentialReactivity C-289 I
Both ASTM C289 and C295 provide guidance for selecting aggregates and cements to avoid alkali-aggregate reactions, and both standards were i specified for use in CCNPPs concrete specification. The aggregates used in l the Auxihary Building concrete were specifically investigated, tested, and j exammed in accordance with the ASTM specifications to determine potential j for reactivity with alkalis. !
2.5 Plausibility Determination 1
Based on the discussion in Section 2.4, the aggregates used in CCNPPs Auxiliary Building concrete were specifically investigated, tested, and I l examined in accordance with the pertinent ASTM specifications to minimize ,
the potential for reactivity with alkahs This conclusion is supported by a 1992 containment walkdown' inspection report 6 tlut documented no t indications of concrete damage due to this mechanism. It is noted that the l Auxihary Building is immediately adjacent to the containment structure and was fabricated using the same 6750-C-9 specification. Additionally, a walkdown in 19947 observed no traces of map cracking on the exposed ,
exterior walls of the Unit-2 Auxihary Building. For these reasons, reactions with aggregates will not degrade any concrete components of the Auxthary Building and will have no adverse impact on the intended functions of these concrete structural components. Therefore, reaction with aggregates is not a ,
plausible aging mechanism for any concrete structural components of the CCNPP Auxiliary Building.
2.6 Existing Programs There are no existing programs at CCNPP that are designed specifically to identify or to repair damage incurred by reaction with aggregates. Since reaction with aggregates is not a plausible aging mechanism tint could degrade the Auxiliary Building structural components, no management programis necessary.
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3.0 CONCLUSION
Since the potential effects of aggregate reactions on all concrete components were well known and understood, measures to avoid using reactive aggregates were implemented for CCNPP in design specification No. 6750-C-9. The aggregates used in the Auxthary Building concrete were specifically investigated, tested, and examined in accordance with applicable ASTM specifications to minimtze any reactivity of aggregates with alkalis.
4.0 RECOMMENDATION Reaction with aggregates is not a plausible aging mechanism for any concrete component of the CCNPP Auxthary Building and requires no further evaluation or recommendation.
5.0 REFERENCES
(v 1. " Class I Structures License Renewal Industry Report," EPRI's Project RP-2643-27, December 1991.
- 2. " Potential Reactivity of Aggregates (Chemical Method)," American Society of Testing and Materials, ASTM C-289-66.
- 3. " Petrographic Examination of Aggregates for Concrete," American Society of Testing and Materials, ASTM C-295-65.
- 4. Letter from Charles County Sand & Gravel Co., Inc. to Bechtel Corporation, June 30,1972.
- 5. " Specification for Furnishing and Delivery of Concrete - Calvert Cliffs ;
Nuclear Power Plant Unit No.1 and No. 2," Design Specification No. ;
6750-C-9, Revision 8, April 1970. i
- 6. "Exammation of the Unit 1 Containment Structure - Calvert Cliffs Nuclear Power Plant," August 1992.
- 7. Walkdown- Auxiliary Building, November,1994.
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APPENDIX E - CORROSION OF EMBEDDED STEEUREBAR -
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1.0 MECHANISM DESCRII'I' ION 1 The environments that induce corrosion of reinforcing steel, embedded steel, and cast-in-place anchor bolts are similar. Therefore, this appendix is applicable to all structural components that are either part of or comprise these three component types.
Concrete's high alkalinity (pH > 12.5) provides an environment around embedded steel /rebar and protects them from corrosion. If the pH is lowered (e.g., to 10 or less), corrosion may occur. However, the corrosion rate is still insignificant until a pH of 4.0 is reached. A reduction in pH can be caused by the leaching of alkaline products through cracks, the entry of acidic materials, or carbonation. Chlorides can be present in constituent materials of the original concrete mix (i.e., cement, aggregates, admixtures, and water), or they may be introduced environmentally. The severity of corrosion is influenced by the properties and type of cement and aggregates (V) as well as the concrete moisture content.
Galvanized decking and galvanized embedments are used in some structures. Since galvanizmg materialis not considered a dissimilar metal, its application will not aggravate corrosion of the structure.
Studies have also been conducted to determine the effects of stray electrical currents on reinforcing steel. Lightning conductors exchange electrons with the atmosphere and, if connected to reinforcing steel, may accelerate the corrosion process. However, while stray electrical currents can aggravate active corrosion, they are not age-related2 Corrosion products have a volume greater than the original metal. The presence of corrosion products on embedded steel or rebar subjects the concrete to tensile stress that eventually causes hairline cracking, rust staining, spalling, and more severe cracking. These actions will expose more embedded steel /rebar to a potentially corrosive environment and cause l further deterioration in the concrete. A loss of bond between the concrete l and embedded steel /rebar will eventually occur, along with a reduction in steel cross sectior Rebar corrosion can cause deterioration of concrete hem a series of hairline cracking, rust staining, spalling, and more severe cracking. These conditions can ultimately impair structural integrity.
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l Corrosion of Embedded Steel /Rebar l
The degree to which concrete will provide satisfactory protection for embedded steel /rebar depends in most instances on the quality of the concrete and the depth of concrete cover over the steel. The permeability of the concrete is also a major factor affecting corrosion resistance. Concrete of low permeability contains less water under a given exposure and, hence, is more likely to have lower electrical conductivity and better resistance to corrosion. Such concrete also resists absorption of salts and their penetration into the embedded steel and provides a barrier to oxygen, an essential element of the corrosion process. Iow water-to-cement ratios and adequate air entramment increase resistance to water penetration and thereby provide greater resistance to corrosion.
2.0 EVALUATION At CCNPP, embedded steel has been used in composite structural members or as anchorages of concrete surface attachments. Liner plate anchorages, either steel studs or structural shapes, used in the spent fuel pool are also considered as embedded steel. Reinforcing steel (rebar) and cast-in-place anchors are both treated as embedded steel in the evaluation of corrosion effects, because the environment and the technical basis for their corrosion induction are similar. The base plates under the columns or those used as part of attachments to the concrete surface are treated as structural steel, and the evaluation of their corrosion effects is addressed in Appendix K. Because the design and inspection requirements of liner plates differ significantly from those of structural steel, the corrosion effect on liner plates is discussed separatelyin Appendix L 2.1 Conditions The only significant inventory of aggressive chemicals stored inside the Auxiliary Building is borated water, and it is pnmarily in safety related systems such as the chemical volume control system. Because of the safety significance of these systems, undetected leakages of borated water for an extended period of time cannot occur. Therefore, the Aux 1hary Building's interior surface and all intemal structural components are not exposed to the risk of aggressive chemicals.
l The primary area of concern is the exterior surface of the Auxiliary Building l where moisture and oxygen may have access to the embedded steel and l rebars. Chlorides in the atmosphere from the Chesapeake Bay could gain
- q access to the steet However, only above-grade portion of the Auxthary
,g Building is exposed to this environment. The below-grade exterior surface 57/96 m E-2 Revision 2
Corrosion of Embedded Steel /Robar could be exposed to groundwater on a more or less continuous basis. A dewatering system, installed during construction 4, would maintain a stable groundwater level at El.+10.0 ft, which is above the elevation of the i Auxihary Building foundation mat.' Ho vever, there is no known program to !
determine if the dewatering system continues to perform its function after construction. Additionally, during construction, a waterproof membrane was installed against all external concrete surfaces below the water table'.
However, the minunum stated life expectancy for the membrane is only five ']
years.
2.2 Potential Aging Mechanism Determination I Corrosion of embedded steel /rebar is a potential aging mecharusm for the following structural components of Auxiliary Building because they are exposed to the outside environment and could be subjected to corrosive i environments:
+ Exterior concrete walls LR functions LR-S-1,2,4,5,6,7 l
+ LR functions LR-S-1,5 l Concrete foundation mat where:
LR-S-1: Provides structural and/or functional support (s) for safety-l related equipment.
LR-S-2: Provides shelter / protection for safety-related equipment.
LR-S-4: Serves as a missile barrier (internal or external).
LR-S-5: Provides structural and/or functional support (s) for non-l safety-related equipment whose failure could directly prevent l satisfactory accomplishment of any of the required safety-related functions.
LR-S-6: Provides flood protection barrier (internal floodmg event).
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LR-S-7: Provides rated fire barriers to confine or retard a fire from spreading or from adjacent areas of the plant.
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- Building; therefore, corrosion of embedded steel /rebar is not a potential
, aging mecharusm.
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i Corrosion of Embedded Steel /Rebar l
l 2.3 Impact on Intended LR Functions If the effects of corrosion of embedded steel /rebar wera not considered in l the original design or are allowed to degrade the above structural l components unmitigated for an extended period of time, this aging l mechanism could affect all the intended LR functions of components listed in Section 2.2.
2.4 Design and Constmetion Considerations The Auxiliary Building was constructed with concrete that complies with CCNPP's design specification No. 6750-C-93, which adheres to the relevant ACI Codes and ASTM specifications for a concrete structure of low permeability. Also proper concrete covers were specified in accordance with ACI 318 Code to effectively prohibit exposure of embedded steel /rebar to the corrosive environment.
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i 2.5 Plausibility Determination Based on the discussion in Sections 2.1 and 2.4, corrosion is not a plausible aging mechanism for embedded steel /rebar in the above-grade portion of the Auxiliary Building exterior walls, and all components inside the Auxthary Building. This conclusion is supported by a contamment 1992 walkdown inspection report 5 that documented no indications of damage to concrete due to corrosion of embedded steel /rebar. The Auxiliary Building is immediately adjacent to the containment and is fabricated with the same concreta specification. Additionally, a walkdown in 19947 observed no traces of damage to concrete due to corrosion of embedded steel /rebar on the exposed exterior walls of the Unit-2 Auxiliary Building.
As discussed in Section 2.1, only the below-grade portion of the exterior walls of the Auxiliary Building and the exterior surface of the Auxiliary Building foundation mat could be exposed to an aggressive environment on a continuous basis and could be susceptible to embedded steel /rebar corrosion. Because the chemical quality of the underground water is not known, corrosion of embedded steel /rebar is a plausible aging mechamsm for the below-grade portion of tha Auxiliary Building exterior walls and the exterior surface of the Auxiliary Building concrete foundation mat.
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,d Sm96 m E-4 Revision 2
l Corrosion of Embedded Steel /Rebar l l There are no existing programs at CCNPP that are designed specifically to identify or to repair damage of the concrete structure due to corrosion of embedded steel /rebar.
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3.0 CONCLUSION
Based on the discussion in Sections 2.1 and 2.4, corrosion of embedded l steel /rebar is not a plausible aging mechanism for concrete components ,
inside the Auxiliary Building and the above-grade portion of the Auxthary 1 Building exterior walls. No further evaluation is required for these concrete structuralcomponents.
Because the quality of the groundwater is not known, corrosion of embedded steel /rebar is a plausible aging mechanism for the below-grade portion of the Auxiliary Building exterior walls and the concrete foundation mat.
- (/ 4.0 RECOMMENDATION An evaluation program is secommended for testing the groundwater quality to determine the plausibility of corrosion of embedded steel /rebar in the below- grade portion of the Auxiliary Building (walls and mat). During initial plant construction, groundwater observation wells were installed to monitor the groundwater table, and samples were taken for groundwater quality testing.6 These wells have been taken out of service. However, ;
several piezometers in the area of the Auxiliary Building are stillin place 8 It l is . recommended that a program be developed to investigate the groundwater chemistry using the existing piezometers. This data can be used to determine if it is plausible that aggressive chemicals have degraded the exterior surface of the Auxiliary Building structure below grade, which would, in tum, indicate if it is plausible that corrosion of embedded steel or rebar has occurred.
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5.0 REFERENCES
- 1. " Class I Structures License Renewal Industry Report," EPRI's Project RP-2643-27, December 1991.
- 2. Skoulikidas, T., Tsakopoulos, A., and Moropoulos, T., " Accelerated Rebar Corrosion When Connected to Lightning Conductors and Protection of Rebars with Needle Diodes Using Atmosphere -
Electricity," in Publication ASTM STP 906, " Corrosion Effect of Stray Currents and the Techniques for Evaluating Corrosion of Rebars in Concrete." -
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- 3. " Specification for Furnishing and Delivery of Concrete - Calvert Cliffs Nuclear Power Plant Unit No. I and 2," CCNPP's Design !
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Specification No. 6750-C-9, Revision 8, April 1970.
1
- 4. "Calvert Cliffs Nuclear Power Plant, Units 1 and 2, Updated Final l l Safety Analysis Report (UFSAR)," Baltimore Gas and Electric Co.
- 5. " Examination of the Unit 1 Containment Structure - Calvert Cliffs
- Nuclear Power Plant," August 1992.
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j 6. " Specification for Furnishing and Installation of Piezometers -
l Calvert Cliffs Nuclear Power Plant Unit No.1 and 2," CCNPP's Design Specification No. 6750-C-23E, Revision 0, November 1973.
- 7. Walkdown - Auxiliary Building, November,1994.
- 8. Drawing 61-523-E, Sheet 1, Yard Piping Plan - Sheet 1", Rev. 27.
- 9. " Specification for Furnishing and Delivering Waterproof Membrane - Calvert Cliffs Nuclear Power Plant Unit No.1 and 2,"
CCNPP's Design Specification No. 6750<-33, Revision 0, December 1968.
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V APPENDIX F - CREEP l
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l 1.0 MECHANISM DESCRIPTION 1 Creep is defined as the time-dependent increase of strain in hardened concrete that has been subjected to sustained stress. The sustained stress results from the dead load and live load of the structure and from I temperature effects. Creep deformation is a function of loading history, l environment, and material properties of the concrete. The time-dependent deformation of concrete under compressive load consists of strain resulting '
from progressive cracking at the aggregate-cement paste interface, from moisture exchange with the atmosphere, and from moisture movement i within the concrete.
The effects of temperatures on creep are not linear. At 122 *F, creep strain is about two to three times as great as at room temperature (68 - 75 F.) But from 122 F to 212 *F, creep strain continues to increase four to six times that l experienced at room temperatures. While little is known about creep rate l beyond 212 F, the maxunum creep rate may have occurred between 122 F (V )
and 176 F.2 l Creep is not visible because micrxracking occurs at the aggregate cement- ;
paste interface. The deformation resulting from cracking and from moisture '
exchange with the atmosphere is not recoverable. Creep deformation can generally be characterized as follows:
+ Increased water-txement ratio results in increased creep magnitude.
+ Increased aggregate-txement ratio results in increased creep magnitude for a given volume of concrete.
+ Creep deformation is approximately proportional to the applied load for a level not exceeding about 40% to 60% of the ultimate strength of concrete.
- Concrete age at application of load affects creep (i.e., the older the concrete, the less the creep).
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+ Crec p increases with increased temperature.
+
/.ggregate with a high modulus of elasticity and low porosity will nunumze creep.
Creep-induced concrete cracks are typically not large enough to result in concrete deterioration or in exposure of the reinforcing steel to environmental stressors. Cracks of this magnitude do not reduce the concrete's compressive scangth. Creep is significant when new concrete is subjected to load and decreases exponentially with time. Any degradation is noticeable in the first few years of plant life. According to ACI 209R-82,278%
of creep occurs within the first year,93% within 10 years,95% within 20 years, and %% within 30 years. At any given stress, high-strength concretes show less creep than low-strength concretes.
ACI 209R-82 provides guidance for predicting creep in concrete structures.
Prestressed concrete structures may be subject to more pronounced creep and relaxation effects, particularly in combination with elevated temperatures.
2.0 EVALUATION 2.1 Conditions There is no condition in CCNPP that could aggravate the effect of concrete creep initiated right after concrete cons >.ruction. Most of the concrete creep will have occurred well before the time of a license renewal application.
Therefore, creep of concrete structural components should not be regarded as an aging mechanism for license renewal.
2.1 Potential Aging Mechanism Determination Creep is not a potential aging mechanism for any Auxiliary Building concrete structu al components because creep proceeds at a decreasing rate with age and is not expected to continue after 40 years.
2.3 Impact on Intended Functions Since creep is not a potential aging mechanism, it will not affect the intended functions of any Auxiliary Building structural components.
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2.4 Design and Construction Considerations At CCNPP, all reinforced concrete components were designed based on the
, working stress design method. The induced stresses are much lower than l the ultimate strength of the concrete, which is specified as f', = 4,000 psi for ,
most of the Auxiliary Building concrete structural components. The Auxiliary Building and its concrete components are subject to low forces (basically only dead load) during normal plant operation condition.
Therefore, creep in all concrete components is nunimal because of the low compressive stresses in concrete and the use of high-strength concrete.
Besides, creep proceeds at a decreasing rate with age; normally, % % of creep has occurred within 30 years.2 Therefore, creep is not expected to continue during the period of extended operation.
2.5 Plausibility Determination Not applicable.
2.6 Existing Programs U Not applicable.
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3.0 CONCLUSION
Most of the concrete creep will have occurred well before the time of license renewal application. Therefore, creep of concrete structural components should not be regarded as an aging mechanism for license renewal.
4.0 RECOMMENDATION Not applicable.
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5.0 REFERENCES
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- 1. " Class I Structures License Renewal Industry Report," EPRI's Project RP-2643-27, December 1991.
- 2. " Prediction of Creep, Shrinkage, and Temperature Effects in ConcreteStructures," AmericanConcreteInstitute, ACI209R-82. !
- 3. " Specification for Furrushing and Delivery of Concrete - Calvert Cliffs Nuclear Power Plant Unit No.1 and 2," CCNPP's -Design-Specification No. 6750-C-9, Revision 8, April 1970.
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v APPENDIX G - SHRINKAGE 1.0 MECHANISM DESCRII'rION2 A workable concrete mix typically contains more water than is needed to offset the effects cf hydration. When concrete is exposed to air, large portions of the free water evapore.te. As water evaporates, capillary tension i develops in the water remauung in the concrete while the concrete dries and i shrmks in volume. Should these stresses exceed the tensile strength of the concrete, a crack forms. Initiai ahnnkage occurs during curing and continues months after placement. Sui:mquent drymg and shnnFage occurs in concrete that is not continuously vet or submerged. According to ACI 209R-822,91% of the shrinkage occure during the first year,98% iri 5 years, and 100 % in 20 years.
Excessive shnnkage causes cracking of the concrete surfaces, which provid.es a means for aggressive elements to make contact with the embedded
, steel /rebar, thus promoting the possibility of corrosion. The aging (d
- mechanism due to corrosion of embedded steel /rebar is discussed in Appendix E.
l 2.0 EVALUATION 2.1 Conditions l
There is no condition in CCNPP that could aggravate the effect of concrete shnnkage initiated right after concrete construction. Most of the concrete shrinkage will have occurred well before the time of a license renewal application. Therefore, shnnkage of concrete structural components should not be regarded as an aging mechanism for license renewal.
2.2 Potential Aging Mechanism Determination Shnnkage is not a potential aging mechamsm for any Auxiliary Building concrete structural components because shnnkage in concrete proceeds at a decreasing rate with age and is not expected to continue after 40 years. I 2.3 Impact on Intended Functions Since shrinkage is not a potential aging mechanism, it will not affect the (c)
U intended functions of any Auxiliary Building structural components.
57B6 m G-1 Revision 2
Shrinkage 2.4 Design and Construction Considerations Since shrmkage can be minimized by keeping the water content of the paste as low as possible, the use of low slump concrete is a major factor in controlling shrinkage.8 As stated in paragraph 12.1.2.1 of CCNPP design specification No. 6750-C-9,4 a nominal slump of 2 inches (4,000 psi strength) was specified for all concrete used in Auxthary Building foundation mat and lower levels. A nominal slump of 3 inches (3,000 psi strength) was specified for the upper levels of the Auxiliary Building.
The development of concrete cracking due to shnnkage is also minimized by providing adequate reinforcing steel, per the ACI 318-63 Code.
Since low slump, high strength, concrete is used at Calvert Cliffs to mimmize concrete cracks from shnnkage and additional rebars are used to mitigate crack propagation, shnnkage of any concrete component of the Auxthary Buildingis mintmal.
2.5 Plausibility Determination Not applicable.
2.6 Existing Programs Not applicable.
3.0 CONCLUSION
Shrinkage in concrete is not a long-term aging mechanism and is not expected to continue after 40 years.
4.0 RECOMMENDATION Not applicable.
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5.0 REFERENCES
- 1. " Class I Structures License Renewal Industry Report," EPRI's Project RP-2643-27, December 1991.
- 2. " Prediction of Creep, Shrmkage, and Temperature Effects in Concrete Structures," American Concrete Institute, ACI 209R-82
- 3. Design and Control of Concrete Mixtures,11th Edition, Portland Cement Association, July 1968.
- 4. " Specification for Furnishing and Delivery of Concrete -
Calvert Cliffs Nuclear Power Plant Unit No. I and 2,"
CCNPP's Design Specification No. 6750-C-9, Revision 8, April 1970.
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APPENDIX H - ABRASION AND CAVITATION 1.0 MECIIANISM DESCRIPTION 2 As water moves over concrete surfaces, it can carry abrasive materials or it can create a negative pressure (vacuum) that can cause abrasion and cavitation. If significant amounts of concrete are removed by either of these !
processes, pitting or aggregate exposure occurs due to loss of cement paste. l l
'lhese degradations are readily detected by visual exammation in accessible locations.
Abrasion and cavitation occur only in concrete structures that are continuously exposed to flowing water. Cavitation damage is not common if velocities are less than 40 fps. In closed conduits, however, degradation due to cavitation can occur at velocity as low as 25 fps when abrupt changes in slope or curvature exist.
2.0 EVALUATION (3
v' 2.1 Conditions Neither the Auxiliary Building nor its structural components are exposed to continuously flowing water.
2.2 Potential Aging Mechanism Determination Attack by abrasion and cavitation is not a potential aging mechanism for the structural components of the Auxiliary Building because the CCNPP Auxiliary Building is not exposed to continuously flowing water.
2.3 Impact on Intended Functions Not applicable.
2.4 Design and Construction Considerations Not applicable.
2.5 Plausibility Determination Not applicable.
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2.6 Existing Programs Not applicable.
3.0 CONCLUSION
The CCNPP Auxiliary Building nor any of its structural components are exposed to continuously flowing water. Therefore, abrasion and cavitation are not a potential aging mechanism for any structural components of the Auxiliary Building.
l i 4.0 RECOMMENDATION Not applicable.
5.0 REFERENCES
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- 1. " Class I Structures License Renewal Industry Report," EPRI's Project l RP-2643-27, December 1991.
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,V APPENDIX l - CRACKING OF MASONRY BLOCK WALLS 1.0 MECHANISM DESCRIFFION1 Masonry Block Walls Masonry blocks walls can be designed as structural or shield walls. Masonry block wall cells may or may not contain reinforcing steel to provide l structural strength for the wall. The extent of grouted cells varies with the specific design requirements for a bearing wall.
Some aging mechanisms that affect masonry block walls are the same as those that affect reinforced concrete walls. The potential for embedded steel and reinforced steel corrosion in block walls is similar to that of reinforced concrete.
Masonry block walls are vulnerable to aging mechanisms. Any restraint imposed on a masonry block wall that will prevent the wall from free expansion or contraction will induce stresses within the wall. Restraint against expansion results in small stresses depending on the strength of the (J) block wall materials and thus rarely causes degradation of the concrete block wall. Moreover, expansion of the wall is offset by shnnkage from carbonation and drying. Restraint against free contraction causes tensile stresses within the wall. If these stresses exceed the tensile strength of the unit, the bond strength between the mortar and the unit, or the shearing strength of the horizontal mortar joint, cracks occur to relieve the stresses.
Expansion or contraction of masonry block walls may be caused by changes in temperature, changes in moisture content of the constituent materials, carbonation, and movement of adjacent structural components (e.g.,
supporting floor or foundations).
Shnnkage due to moisture loss is among the principal causes of volume changes in masonry block walls. Factors affecting the drying shnnkage are )
the type of aggregate used, the method of cunng, and the method of storage.
Units made with sand and gravel aggregate will normally exhibit the least
! shrinkage; those with pumice, the highest. The difference between the moisture content of the masonry units during construction and the buildir:g l in use will determine the amount of shnnkage that occurs. High-pressure '
steam curing and proper drying of concrete masonry units reduce the potentialshnnkageof thewalls.
I If proper isolation is not provided at the joint between the masonry block wall and the supporting structural components (e.g., floor slabs or beams),
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l Durability of the masonry mortar used at the block joints may affect the long-term structural integrity of the masonry block wall. Although aggressive environments and the use of unsound materials may contribute l to the deterioration of mortar joints, most degradation results from water
_ entering the concrete masonry and freezing.
The mechamsms cited above which cause cracking of concrete block walls are age-related. Although they are ongoing processes throughout a plant's life, most cracking occurs in the early stages of plant operation.
Concrete Block Shield Walls Solid concrete blocks used for shielding are solid masonry blocks. The discussions above for Masonry Block Walls are also applicable to Concrete ;
Block Shield Walls.
O O 2.0 EVALUATION 2.1 Conditions Masonry Block Walls Masonry block walls exist on every floor level of the Auxiliary Building. The walls are only restrained at the top and bottom.
Concrete Block Shield Walls Concrete Blocks (Shielding) are also located throughout the Auxiliary Building. The blocks are solid concrete with densities between 130 and 140 pcf. The concrete blocks are stacked to form walls which are then laced with l steel for stability and strength. Horizontal and vertical concrete block joints i are mortared. Concrete Block Shield Walls are supported by plate anchorages to the floor slab; they are not restrained between existing concrete walls or slabs.
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2.2 Potential Aging Mechanism Determination Cracking of Masonry Walls is a potential aging mechanism for the following structural components of Auxthary Building because they could be exposed to conditions that are conducive to cracking of Masonry Block Walls and Concrete Block Shield Walls, as discussed in Section 1.0:
+ Concrete Blocks (Shielding) LRfunction LR-S-2
+ Masonry Block Walls LR functions LR-S-1,2,5,6,7 '
where:
LR-S-1: Provides structural and/or functional support (s) for safety-related equipment.
LR-S-2: Provides shelter / protection for safety-related equipment.
LR-S-4: Serves as a missile barrier (internal or extemal).
LR-S-5: Provides structural and/or functional support (s) for non-safety-related equipment whose failure could directly prevent satisfactory accomplishment of any of the required safety-related functions.
LR-S-6: Provides flood protection barrier (internal flooding event).
LR-S-7: Provides rated fire barriers to confine or retard a fire from spreading to or from adjacent areas of the plant.
2.3; Impact on Intended Functions If the effects of cracking of the Masonry Block Walls and Concrete Block Shield Walls were not considered in the original design or are allowed to degrade the above structural components unmitigated for an extended j period of time, this aging mechanism could affect the intended functions of the components listed in Section 2.2.
2.4 Design and Construction Considerations The Masonry Block Walls and Concrete Block Shield Walls complies with O CCNPP's design specification, 6750-A-22, which assured proper moisture 5/7/96 a I-3 Revision 2
( Cracking of Masonry Block Walls
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, content, aggregates, curing and storage to reduce the possibility of cracking.
Additionally, the walls are not fully restrained, are not exposed to outside weather conditions, and are fabricated with sand and gravel aggregates.
All safety-related block walls located at Calvert Cliffs Nuclear Power Plant 1 (CCNPP) were reevaluated per NRC Bulletin 80-11. In order to perform the '
required reevaluation, the condition of the blockwalls and the types of equipment attached were identified during extensive walkdowns. All walls - !
were found to be constructed satisfactorily and were qualified by calculation, using elastic design criteria. BG&E response to this I.E. Bulletin ,
l is discussed in the UFSAR Supplementary Material, located in the beginning l l of Volume 1 of the CCNPP UFSAR, Revision 173 l i i 2.5 Plausibility Determination Based on the discussion in Sections 2.1 and 2.4, and on a walkdown i
performed in November,19944, which inspected the accessible portions of l approximately 15 walls and found no cracks, cracking of Masonry Walls is not a plausible aging mecharusm for the Auxiliary Building Masonry Walls l
/O or the Concrete Block Shield Walls.
V 2.6 Existing Programs There are no existing programs at CCNPP that are designed specifically to identify or to repair cracking of Masonry Block Walls or Concrete Block Shield Walls inside the Auxihary Building. Since cracking of Masonry Block
[ Walls is not a plausible aging mechanism for the Masonry Block Walls or the l Concrete Block Shield Walls in the Auxiliary Building, no management l programis necessary.
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3.0 CONCLUSION
Since the. Masonry Block Walls and the Concrete Block Shield Walls are l constructed with constituents that resist cracking; were properly cured and stored; are only restrained in one direction; are not exposed to outside weather and show no signs of cracking 3; degradetion due to cracking of the Masonry Blocl; Walls in the Auxiliary Building is not plausible.
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4.0 RECOMMENDATION Cracking of Masonry Block Walls is not a plausible aging mechanism for any structural component in the Auxthary Building No further evaluation or recommendationis required.
5.0 REFERENCES
- 1. " Class I Structures License RenewalIndustry Report," EPRI's Project RP-2643-27, December 1991.
- 2. " Specification for Furnishing, Delivery and Erection of the Building Masonry - Calvert Cliffs Nuclear Power Plant Units No.1& 2",
Specification 6750-A-2, Rev.1, September,1970.
- 3. Calvert Cliffs Nuclear Power Plant Units 1 and 2, Updated Final Safety Analysis Report UFSAR Supplementary Material, Rev.17, Supplementary Material (Located at beguunng of Volume 1).
4
- 4. Walkdown - Auxiliary Building, November,1994.
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5f786 a I-5 Revision 2
/"'s APPENDIX J - SETTLEMENT U -
1.0 MECHANISM DESCRIl7FION2 All structures settle during construction and for months after construction.
The amount of settlement depends on the physical properties of foundation material. These properties range from rock (with little or no settlement likely) to compacted soil (with some settlement expected). Settlement may occur during the design life from changes in environmental conditions, such as lowering of the groundwater table. Settlement can occur in two stages:
elastic expansion and time-dependent settlement. Elastic expansion of the confined soil occurs due to excavation unloading and results in a slightly upward movement. During construction, the soil moves downward as load is applied. This elastic movement should be small and is complete when construction is completed. It has no effect on the structure and is not considered an aging mechanism 2 The excavation unloading and structural loading cause a small change in the void ratio of the soil. This change results in a very small amount of time-dependent settlement. The settlement rate will decline after completion of construction.
Settlement of structures is usually small and is typically determined by
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U survey. Concrete and steel structural members can be affected by differential settlement between supporting foundations, within a building, or between buildings. Severe settlement can cause misalignment of equipment and lead to overstress conditions within the structure 3 When buildings experience significant settlement, cracks in structural members, differential elevations of supporting members bridging between buildings, or both may be visibly detected.
2.0 EVALUATION 2.1 Conditions 2 The foundation mat ele"ation of the Auxiliaiy Building at CCNPP varies l from approximately 50 feet to 70 feet below the average ground elevation.
The foundation mat is situated on Miocene soil, which is exceptionally dense l and will support heavy foundation loads. The major soil types are sandy l silts, silty sands, and slightly clayed sands. The ultimate bearing capacity of
! the foundation strata is in excess of 80,000 psf, and the allowable bearing capacity is 15,000 psf. However, the design bearing pressure of the foundation mat is 8,000 psf. The soil bearing pressure was about the same as the overburden removed due to excavation.
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l Settlement l 4 I
l l i l l l 2.2 Potential Aging Mechanism Determination i I
Settlement is a potential aging mechanism for all structural components in the Auxthary Building. However, since the concrete foundation mat is the l only structural component directly supported by the soil media, and also for
! convenience of discussion, only the concrete foundation mat is identified as l the structural component subject to the aging mechanism due to settlement.
< 1 l -
Concrete foundation mat LR-S-1, 5 l l
where:
LR-S-1: Provides structural and/or functional support (s) for safety-
- related equipment.
i LR-S-5: Provides structural and/or functional support (s) for non-safety-related equipment whose failure could directly prevent j satisfactory accomplishment of any of the required safety-related i functions.
1 g
2.3 Impact on Intended Functions i If the effects of settlement were not considered in the original design or are l allowed to degrade the above structural component unmitigated for an I
extended period of time, this aging mechanism could affect the functions of l the concrete foundation mat.
l 2.4 Design and Construction Considerations In addition to soil bearing capacity, settlement of the Auxiliary Building foundation mat was also investigated in the design of the Auxiliary Building. A maximum post-construction settlement of 1/2 inch was predicted in the original Auxiliary Building design 2. Since the concrete mat is a rigid foundation and is situated on a exceptionally dense soil, the Auxiliary Building tends to uniformly settle as a rigid body. Most of the predicted 1/2 inch settlement is in terms of uniform settlement, which has no adverse effect on the structural components of the Auxthary Building. A small fraction of the 1/2 inch settlement will be in terms of differential settlement. It is so small that the effect on the structural component is negligible.
- O 5!7/96 a J-2 Revision 2 l
Settlement The excavation for the Auxiliary Building was below the groundwater table.
A dewatering system was installed during plant construction to mamtain the groundwater table at El.10'-0".2 This groundwater table level was considered in the original design of all underground structures?
2.5 Plausibility Determination Based on the discussion in Sections 2.1 and 2.4, the soil type at the CCNPP Auxiliary Building is exceptionally dense, and the design bearing pressure is about the same as that of the removed overburden and is much snudler than the allowable bearing capacity. As discussed in Section 2.4, the predicted settlement-is small and the differential settlement is negligible. A dewatering system was installed to muumize the fluctuation of groundwater table, thus providing stable geological conditions of the plant site. Therefore, settlement is not a plausible aging mechanism for any structural components of the Auxiliary Building.
2.6 Existing Programs There are no existing programs at CCNPP that are designed specifically to O~ identify or to repair damage to concrete incurred by settlement. Since this is not a plausible aging mechanism that could degrade the Auxihary Building structural components, no management program is necessary.
3.0 CONCLUSION
CCNPP's Auxiliary Building is situated on Miocene soil, which is exceptionally dense and will support heavy foundation loads. Additionally, the structural load on the foundation mat is about the same as the removed overburden weight. Therefore, the soil bearing stress is well below its ultimate bearing capacity, and the long-term settlement is predicted to be only 1/2 inch.2 In addition, the settlement rate declined after completion of construction. Long-term settlement is not expected to continue after 40 years. Therefore, settlement is not a plausible aging mechanism for the structural components of the Auxiliary Building.
4.0 RECOMMENDATION Settlement is not a plausible aging mechanism for the concrete foundation mat of the Auxiliary Building and requires no further evaluation or recommendation.
57/96 a J-3 Revision 2
Settlement
5.0 REFERENCES
- 1. " Class I Structures License Renewal Industry Report," EPRI's Project RP-2M3-27, December 1991.
- 2. "Calvert Cliffs Nuclear Power Plant, Units 1 and 2, Updated Final Safety Analysis Report (UFSAR)," Baltimore Gas and Electric Co.
- 3. Civil and Structural Design Criteria for Calvert Cliffs Nuclear Power Plant, Units 1 and 2, by Bechtel Power Corporation, Revision 0, August 2,1991.
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5786 a J-4 Revision 2
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e APPENDIX K - CORROSION OF STEEL 1.0 MECIIANISM DESCRIPTION' l
Steel corrodes in the presence of moisture and oxygen as a result of electrochemical reactions. Initially, the exposed steel surface reacts with oxygen and moisture to form ari oxide film as rust. Once the protective oxide film has been formed and ifit is not disturbed by erosion, attemating wetting and drying, or other surface actions, the oxidation rate will diminish rapidly with time. Chlorides, either from sea water, the atmosphere, or groundwater, increase the rate of corrosion by increasing the electrochemical activity. If steel is in contact with another metal that is more noble in the galvr.nic series, corrosion may accelerate.
In some cases, corrosion of structural steel in contact with water may be microbiologically induced due to the presence of certain organisms, which is sometimes referred to as microbiologically influenced corrosion (MIC). These organisms, which include microscopic forms such as bacteria and macroscopic types such as algae and bamacles, may influence corrosion on steel under broad ranges of m pressure, temperature, humidity, and pH. MIC effects on carbon steel may result in random pitting and general corrosion.
The rate of steel corrosion depends on site-specific environmental conditions and measures taken to prevent corrosion. A steel structure surface subjected to alternately wet and dry conditions corrodes faster than one exposed to continuously wet conditions. Atmospheric corrosion proceeds much more rapidly in areas where the atmosphere is chemically polluted by vapors of sulfur oxides and similar substances. Steel will corrode much faster in the vicinity of sea water because of sodium chloride in the atmosphere. The corrosion rate of steel usually increases with rising temperatures.
Corrosion products such as hydrated oxides of iron (rust) form on exposed, !
unprotected surfaces of the steel and are easily visible. The affected surface may )
degrade such that visible perforation may occur. In the case of exposed surfaces of structural steel with protective coatings, corrosion may cause the protective coatings to lose their ability to adhere to the corroding surface. In this case, damage to the coatings can be visually detected well in advance of significant degradation.
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5f7/96 a K-1 Revision 2
Corrosion of Steel 2.0 EVALUATION 2.1 Conditions Steel can corrode in the presence of moisture and oxygen as a result of electrochemical reactions, especially in areas where there is an inadequate drainage system. Stmetural steel components especially vulnerable to corrosion are those members that are in areas that can form pockets to harbor liquids.
2.2 Potential Aging Mechanism Determination Corrosion is a potential aging mechanism for the following Auxiliary Building structural steel components because conditions conducive to steel corrosion discussed in Sections 1.0 and 2.1 exist:
+ Steel columns LR functions LR-S-1,5
+ Steel beams LR functions LR-S-1,5
+ Base plates LR functions LR-S-1,5
+ Floor framing LR functions LR-S-1,5
+ Roofframing/ trusses LR functions LR-S-1,4,5
+ Steel bracing LR functions LR-S-1,5
+ Platfonn hangers LR functions LR-S-1,5
+ Decking LR functions LR-S-1,5
+ Jet Impingement Barriers LR functions LR-S-1,5
+ Fire Doors, Jambs, & Hardware LR function LR-S-7
+ Access Doors, Jambs, & Hardware LR function LR-S-2
+ Watertight Doors LR function LR-S-6,7
+ Roll-up Doors LR function LR-S-2
+ New Fuel Rack Assembly LR function LR-S-1
'Q) 5786 a K-2 Revision 2
1.
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Corrosion of Steel l
- Monorail l LR function LR-S-5
+ Cask Handling Crane Rail /Supts LR function LR-S-1,5
+ Pipe Whip Restraints LR function LR-S-2
+ Cast-in-place anchors LR functions LR-S-1
- Post-installed anchors LR function LR-S-1 where:
l LR-S-1: Provides structural and/or functional support (s) for safety-related equipment.
LR-S-2: Provides shelter / protection for safety-related equipment.
LR-S-4: Serves as a missile barrier (internal or external).
l' LR-S-5: Provides structural and/or functional support (s) for non-safety-related equipment whose failure could directly prevent satisfactory accomplishment of any of the required safety-related functions.
LR-S-6: Provides flood protection barrier (internal flooding event).
LR-S-7: Provides rated fire barriers to confine or retard a fire from a spreading to or from adjacent areas of the plant. l 2.3 Impact on Intended Functions If corrosion of steel is allowed to degrade the above structural steel components l unmitigated for an extended period of time, this aging mechanism could affect all intended functions of components listed in Section 2.2.
2,4 Design and Construction Considerations Since corrosion was considered a potential degradation mechanism for all structural steel components of the Auxiliary Building, its effects were considered in the
- original design. As a result, all exposed structural steel surfaces in the Auxiliary
[ Building except grating, checkered plates, and metal decking, which are galvanized i steel, were shop-painted or field-painted during the construction phase in accordance 2 3 i with CCNPP's design specifications No. 6750-C-31 and No. 6750-A-24 .
-57B6 m K-3 Revision 2
Corrosion of Steel Maintenance of protective coatings on CCNPP's equipment and structures follows
- the requirements specified in Calvert Cliffs Nuclear Program Interdepartmental Procedure MN-3-100'. His program sets forth procedural controls that comply with 10 CFR Part 50, Appendix B and satisfy the protective coating requirements in Regulatory Guide 1.54 which endorses ANSI N101.4-1972. His MN provides the requirements for coating and recoating new stmetural components and the refurbishment of existing structural components in the Auxiliary Building (as well as the Containment and balance of plant). Application of coatings at CCNPP follows standard procedures specified in TRD-A-10001 Galvanic material on steel components is one of the protective coating systems.
Maintenance of galvanic coatings is covered under the same maintenance program as paint and other protective coatings.
2.5 Plausibility Determinattan Based on the discussion in Sections 2.1,2.3 and 2.4, corrosion could affect the intended functions of all structural steel members and is, therefore, a plausible aging p mechanism for all steel components listed in Section 2.2.
d 2.6 Existing Programs 6
System engineer walkdowns under PEG-7 will provide the discovery mechanism for degraded coating conditions. Conditions adverse to quality (such as degraded 7
paint or corrosion) are reported in an Issue Report under QL-2-100. He coatings 5
program under MN-3-100 provides the administrative control over how corrective actions are performed. He combination of these existing plant programs will ensure that corrosion effects on accessible structural steel are adequately managed, nese programs do not provide for the evaluation of the coating condition on structural steel components that are not normally accessible. An age related degradation inspection program as defined in the BGE Integrated Plant Assessment Methodology is necessary to address the aging effects of the non-accessible structural steel components.
3.0 CONCLUSION
All structural steel components of CCNPP's Auxiliary Building are vulnerable to corrosion attack if a corrosive environment prevails. All exposed stmetural steel surfaces in the Auxiliary Building are covered by a protective coating. Aging management of degraded coating conditions on accessible structural steel in the Auxiliary Building is accomplished through the combination of existing plant programs. liowever, structural steel components not readily accessible require O additional aging management.
5/7N6 a K-4 Revision 2
Corrosion of Eteel 4.0 RECOMMENDATION All painted and galvanized structural steel components in the Auxiliary Building should be inspected to evaluate the condition of the coating, and repaired as required Coatings on structural steel in accessible areas are adequately managed by existing plant programs. A new program utilizing an age related degradation inspection i should be developed to address degradation of coatings on structural steel components that are not normally accessible. ,
I
5.0 REFERENCES
1
- 1. " Class 1 Structures License Renewal Industry Report," EPRI's Project RP-2643-27, December 1991.
- 2. " Specification for Furnishing, Detailing, Painting, and Delivering Containment and Auxiliary Building Structural Steel," CCNPP's Design Specification No. 6750-C-31, Revision 2, May 1970. )
l
- 3. " Specification for Painting and Special Coatings," CCNPP's Design l Specification No. 6750-A-24, Revision 12, October 1982.
- 4. " Painting and Other Protective Coatings," CCNPP's Administrative Procedure MN-3-100, Rev. 2.
- 5. " Coating Application Performance Standard," TRD-A-1000, Calvert Cliffs Nuclear Power Plant, Unit No. I and 2, Revision 8, August 1991.
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l Srh96 a K-5 Revision 2
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C APPENDlX L - CORROSION OF LINER 1.0 MECIIANISM DESCRIITIONu 1.1 Spent Fuel Pool Stainless Steel Liner The stainless steel liner may be subject to stress corrosion cracking (SCC),
which is defined as cracking under the combined actions of > 3sion and.
tensile stresses. The phenomenon of SCC can result in fractu M .he metal.
The stresses may be either applied (extemal) or residual (unernal). The stress corrosion cracks themselves may be either transgranular or intergranular, depending on the metal and the corrosive agent. As is normal in all cracking, the cracks are perpendicular to the tensile stress. Usually there is little or no obvious visual evidence of corrosion. The three principal factors necessary to initiate stress corrosion cracking are tensile stresses, corrosive environment, and susceptible material. The tensile stresses necessary to cause SCC must be at or near the material's yield point. This is facilitated when the materialis substantially cold worked, contains residual stress from welding, or is subjected to significant applied loads. Different corrosive environments induce different levels of SCC on various materials.
With respect to material susceptibility, austenitic stainless steels, such as SA-
[]
v 240 Type 304, are prone to SCC, particularly when sensitization is present as in heat-affected zones and at creviced geometries.
In a sensitized condition, Type 304 stainless steel may develop intergranular stress corrosion cracking (IGSCC). The heat-affected zones of welds in Type 304 stainless steel are potential sites for IGSCC. IGSCC occurs when changes in the microstructure take place due to the welding heat, rendering the heat-affected zones " sensitized", and when high residual stresses occur in and around the welds. The degree of sensitization depends on the metal's composition. For example, sensitization usually occurs when Cr in boundaries combines with carbon. A low carbon content stainless steel, such as Type 304L, is relatively immune to IGSCC in the fuel pool environments.
This is because the low carbon content (0.03 percent maxunum) of Type 304L results in sensitization levels during welding so low that its heat-affected zones are resistant to IGSCC in the fuel pool environments.
1.2 Spent Fuel Racks !
Spent Fuel Racks are fabricated from thin stainless steel material and are also submerged in borated water, as are the liner plates. Therefore, the mechanism descriptions provided in section 1.1, above, are applicable for Spent Fuel Racks. l
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S'7,96 m L-1 Revision 2 J
OV Corrosion of Liner l 2.0 EVALUATION l .
The stainless steel liner and the Spent Fuel Racks do not have dissimilar metals; therefore, they are not subject to galvanic corrosion. ,
i 2.1 Conditions Spent Fuel Pool Liner The Spent Fuel Pool liner at CCNPP is SA-240 Type 304 stainless steel? The liner was constructed from a series of individual steel plates welded together. Both the plate material and the welds are subject to the same potential degradation mechanisms. The significance of potential degradation of the liners is considered to apply equally to the plate material and the welds.2 l SA-240 Type 304 stainless steel used for the Spent Fuel Pool Liner is resistant to electrochemical corrosion in the spent fuel pool environments. .The r
3 corrosion rate of this steel ranges from 0.05 mil in 100 years (virtually no corrosion) to less than 0.01 mil per year in a borated fuel pool water environment.4 Therefore, the electrochemical corrosion is negligible and is not a potential aging mechanism for the stainless steelliner.
The stainless steel liner in the Spent Fuel Pool is not a load-bearing structural component. The induced strains in the liner, resulting from conformation to deformation of the concrete wall of the Spent Fuel Pool, are negligible under normal plant operating conditions. The liner is not exposed to corrosive environmental conditions under normal operating conditions. Therefore, the conditions for SCC to occur do not exist for the stainless steel liner in the Spent Fuel Pool.
The heat-affected zones of welds at the stainless steelliner are potential sites for " sensitization." Sensitized Type 304 stainless steelis susceptible to IGSCC in boric acid solution.2 Degradation of the stainless steelliner due to IGSCC in the liner is typically evidenced by leakage and detected by observation of an increased amount of pool water leakage.
Spent Fuel Racks The Spent Fuel Racks are high density racks installed in the 1980's and are l fabricated from Type 304L stainless steel 6 Per reference 1, Type 304L is l relatively immune from IGSCC and as such is not a plausible aging
,5 mechanism for the racks.
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i 5786 E L-2 Revision 2
1 l
Corrosion of Liner p} . --
The Spent Fuel Rack stainless steel is a load-bearing structural component.
However, the induced stresses in the plates and welds, due to supporting spent fuel assemblies, are very small under normal plant operating l l conditions. Additionally, the racks are fabricated from Type 304L stainless !
steel, which makes the welds potentially susceptible to IGSCC in the spent i fuel pool environment.2 2.2 Potential Aging Mechanism Determination Corrosion is a potential aging mechanism for the following structural components of Auxiliary Building because conditions exist that are conducive to corrosion of stainless steel liner plates, as discussed in Section 1.0:
+ Spent FuelPool Liner LR function LR-S-3 (stainless steelliner) l
+ Spent Fuel Racks LR function LR-S4 (stainless steel) where:
LR-S4: Provides structural and/or functional support, or both, to safety-related equipment.
LR-S-3: Serves as a pressure boundary or fission product retention barrier to protect public health and safety in the event of any postulated DBEs.
l 2.3 Impact on Intended Functions If the effects of corrosion of the liner and racks were not considered in the original design or are allowed to degrade the above structural components
! unmitigated for an extended period of time, this aging mechanism could affect the intended functions of the components listed in Section 2.2.
2.4 Design and Construction Considerations l
The Spent Fuel Pool Liner was not designed to carry any design loads and was designed only as a leaktight barrier.3 Under normal operating conditions, the imposed strain on the liner due to conforming to concrete O-Sf786 m L-3 Revision 2
p Corrosion of Liner b
deformation is very small and is negligible because the stresses in the Spent Fuel Pool concrete components are mirumal.
The Spent Fuel Racks were designed to carry design loads (dead loads and seismic). Under normal operating conditions, the imposed strain on the racks, due to the dead weight of the fuel assemblies,is very small.
2.5 Plausibility Determination Based on the discussion in Section 2.1, corrosion in sensitized zones of the Spent Fuel Pool Liner due to IGSCC is a plausible aging mechamsm.
Based on the discussion in Section 2.1, corrosion in the sensitized zones of the Spent Fuel Racks due to IGSSC is not a plausible aging mechanism 2.6 Existing Programs Leakage of the Spent Fuel Pool is addressed by leakage testing described in OI-24D5 V The Spent Fuel Pool Liner is fabricated from stainless steel plate, welded together at channel leak chases. These leak chases flow to " telltale valves".
There are a total of ten valves in the SFP (four vertical and one floor for each unit). Monthly, the valves are opened, drained, and are monitored for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> with drip bags. Historically, no more than several hundred cubic centimeters of water have been collected during the 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, and frequently no water is reported. The water that has been collected has always been shown not to be borated, therefore, most likely, not even from the SFP. With approximately 600,000 gallons of water in the SFP, the potential leakage of less than a liter of water is insignificant. Additionally, pumps capable of j supplying up to 160 GPM, are available, continuously, to provide pool l
makeup water if necessary.
3.0 CONCLUSION
For the stainless steel liner of the Spent Fuel Fool, degradation due to IGSCC of heat-affected zones of welds may cause the liner to leak. Therefore, !
IGSCC of the stainless steel liner is a plausible aging mechanism for the Spent Fuel Pool Liner.
3 As noted in Section 2.1, degradation due to IGSCC of heat-affected zones of welds in not a plausible aging mechanism for the Spent Fuel Racks.
5726 m L-4 Revision 2
O Corrosion of Liner b
4.0 RECOMMENDATION Based on the above discussion, the following recommendation is made:
Since, historically, leakage of the SFP has been shown to be negligible and since programs are in place that periodically monitor for leakage (per the existing programs, an Issue Report would be generated if any appreciable amount of borated water or if excessive leakage is noted in the " telltale" valves), no further action is required.
5.0 REFERENCES
- 1. " Pressurized Water Reactor Containment Structures License Renewal Industry Report," NUMARC Report 90-01, Revision 1, September 1991.
- 2. " Class I Structures License Renewal Industry Report," EPRI's Project RP-2643-27, December 1991.
- 3. " Specification for Stainless Steel Liner Plate and Spent Fuel Pool Bulkhead Gate," CCNPP's Design Specification No. 6750-C-28, Revision 5, June 1973.
- 4. " Safety Evaluation Report Related to the Operation of Comanche Peak Steam Electric Station, Units 1 and 2," NUREG-0797, July 1981.
- 5. " Spent Fuel Pool Cooling - Infrequent Operations", Operating Instructions OI-24D, Rev. 0
- 6. " Safety Evaluation by the Office of Nuclear Reactor Regulation Supporting Amendment Nos. 47 and 30 to Facility Operating license Nos. DPR-53 and DPR-69 Relating to Modification of the Spent Fuel Pool Baltimore Gas & Electric Company Calvert Cliffs Nuclear Power Plant Unit Nos.1 & 2, Docket Nos. 50-317 and 50-318", September 1980.
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O APPENDIX M - CORROSION OF TENDONS V
1.0 MECHANISM DESCRIPTION 2 When corrosion of prestressing tendons occurs, it is generally in the form of localized corrosion. Most corrosion-related failures of prestressing tendons have been attributed to pitting, stress corrosion, hydrogen embrittlement, or somecombinationof these.
Pitting is a highly localized form of corrosion. The primary parameter affecting its occurrence and rate is the environment surrounding the metal.
The presence of halide ions, particularly chloride ions, is associated with pitting corrosion.
Stress corrosion results from the simultaneous presence of a conducive environment, a susceptible material, and tensile stress. The environmental factors known to contribute to stress corrosion cracking (SCC) in carbon steels are hydrogen sulfide, ammonia, nitrate solutions, and seawater.
Prestressing tendon anchor heads, which are constructed of a high strength, low alloy steel bolting material, are vulnerable to SCC.
Hydrogen embrittlement (technically, not a form of corrosion) occurs when hydrogen atoms, produced by corrosion or excessive cathodic protection potential, enter the metal lattice. Hydrogen produced by corrosion is not usually sufficient to result in hydrogen embrittlement of carbon steel.
Cathodic polarization is the usual method by which this hydrogen is produced. The interaction between the dissolved hydrogen atoms and the metal atoms results in a loss of ductility manifested as brittle fracture.
Corrosion of prestressing wires causes cracking or a reduction in the wires' cross-sectional area. In either case, the prestressing forces applied to the i l
concrete are reduced. If the prestr.:ssing forces are reduced below the design level, a reduction in design margin results.
2.0 EVALUATION 2.1 Conditions Not applicable. There are no tendons in the Auxiliary Building.
2.2 Potential Aging Mechanism Determination Not applicable.
57&6 -u M-1 Revision 2
i O
D Corrosion of Tendons 2.3 Impact on Intended Functions Not applicable.
2.4 Design and Construction Cor.siderations Not applicable. 1 2.5 Plausibility Determination Not applicable.
2.6 Existing Programs j Not applicable.
3.0 CONCLUSION
O Corrosien of tendons is not a plausible degradation mechamsm for CCNPP's Auxiliaiy Building.
4.0 RECOMMENDATION i Not applicable.
1
5.0 REFERENCES
- 1. " Pressurized Water lieactor Containment Structures License Renewal Industry Report," NUMAR ; Sport 90-1, Revision 1, September 1991.
O Sf7/96 -n M-2 Revision 2
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l APPENDIX N - PRESTRESS LOSSES i 1.0 MECHANISM DESCRII'rION1 As the plant ages, tendons that were prestressed during construction tend to lose tension. Termed prestress losses, these reductions in stress are not readily observable. Several factors contribute to prestress losses:
+ Stress relaxation of prestressing wires
+ Shrinkage, creep, and elastic deformation of concrete
+ Anchorage seating losses
+ Tendon friction j 1
+ Reduction in wire cross section due to corrosion i With the exception of corrosion-induced wire cross-sectional loss, predictions of prestress losses were calculated during design to ensure the i containment can maintain its pressure capacity under postuhted DBE inside C the containment.
2.0 EVALUATION 2.1 Conditions Not applicable. There are no tendons in the Auxiliary Building.
2.2 Potential Aging Mechanism Determination Not applicable.
2.3 Impact on Intended Functions I Not applicable.
i 2.4 Design and Constmetion Considerations l
! Not applicable.
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l 57N6 E N-1 R: vision 2 i
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[p Prestress Losses
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l 2.5 Plausibility Determination Not applicable.
2.6 Existing Programs Not applicable.
3.0 CONCLUSION
l Prestress losses is not a plausible degradation mechanism for CCNPP's l Auxihary Building.
l 4.0 RECOMMENDATION l
Not applicable.
5.0 REFERENCES
l l 1. " Pressurized Water Reactor Containment Structures License l Renewal Industry Report," NUMARC Report 90-1, Revision 1, j September 1991, i 1
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(] APPENDIX O - WEATHERING l G'
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, 1.0 MECHANISM DESCRIITION 2 l
l Components and structures that are located in an environment that is i
exposed to ambient conditions are susceptible to degradation due to weathering (indoor or outdoor). Aging mechanisms associated with weathering include exposure to sunlight (ultraviolet exposure), changes in humidity, ozone cycles, temperature and pressure fluctuations, and snow, rain, or ice. The effects of weathering on most materials are evidenced by a l decrease in elasticity (drying out), an increase in hardness, and shnnkage.
l 2.0 EVALUATION i 2.1 Conditions l
l According to Specification ASTM C33-82, " Standard Specification for Concrete Aggregates,a 2 the CCNPP site is located in the geographic region subject to severe weathering conditions. All outdoor components will experience the extreme temperature ranges, rain, snow, and changes in
_h i
i (d humidity expected at the CCNPP site. Additionally, inside the Auxiliary Building, components will also experience similar temperature and humidity changes, throughout the life of the plant.
2.2 Potential Aging Mechanism Determination Degradation by weathering is a potential aging mecharusm for the following Auxiliary Building components because they are exposed to outdoor conditions or similar in-building conditions:
. caulking and scalants Functions LR-S-2,6, and 7
. expansion joints (joint material) Functions LR-S-2 and 7 ,
where:
! l LR-S-2: Provides shelter / protection for safety-related equipment.
LR-S-6: Provides flood protective barrier (intemal flooding event).
LR-S-7: Provides rated fire barriers to confine or retard a fire from spreading to or from adjacent areas of the plant.
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p Weathering G
23 Impact on Intended Functions If the effects of weathering were not considered in the original design or are allowed to degrade the above components unmitigated for an extended period of time, this aging mechamsm could affect all the intended functions of the components listed in Section 2.2.
2.4 Design and Construction Considerations The caulking and sealants and expansion joints are components which are typically replaced on condition. However, inspections have indicated that a program of inspection and maintenance is required to be developed. Issue Report IR1995-01698 3 was written to address this issue.
2.5 Plausibility De'ermination Based on the discussion in Sections 23 and 2.4, weathering has been f- determined to be plausible for the caulkmg and sealants and expansion
{g j joints in the CCNPP Auxiliary Building.
2.6 Existing Programs The caulking and sealants and expansion joints which perform a fire barrier function are addressed under the Appendix R Program as implemented by procedure STP-F-592-1/2 4 for penchation fire barrier inspection. This j procedure was determined to be adequate for managing the effects of i weathering for the caulking and sealants and expansion joints. l
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3.0 CONCLUSION
Weathering is a plausible aging mechanism for the caulking and scalants and expansion joints in the Auxiliary Building. Management of the aging mechanism for caulking and sealants and expansion joints which perform functions other than fire barrier will be established in conjunction with the resolution to Issue Report IR1995-01698. The Appendix R' Program addresses the aging management for caulking and scalants and expansion joints which perform a fire barrier function.
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57/96 E O-2 Revision 2
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U Weathering 4.0 RECOMMENDATION Caulking and sealants and expansion joints which act as fire barriers are currently maintained through implementation of the Appendix R inspection program (STP-F-592-1/2). However, caulkmg and sealants and expansion joints which perform intended functions other tbn fire barrier do not have a program to manage their aging. An inspection. program should be established in conjunction with the resolution to Issue Report IR1995-01698 to manage the effects of weathering for the caulking and sealants and expansion joints not included under the Appendix R Program.
5.0 REFERENCES
- 1. " Class I Structures License Renewal Industry Report," EPRI's Project RP-2643-27, December 1991.
- 2. " Standard Specification for Concrete Aggregates," American Society of Testing and Materials, ASTM C33-82.
d 3. BGE Issue Report IR1995-01698, Building Joints (Aux. Bldg.
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Exterior), dated 07/13/95.
- 4. " Penetration Fire Barrier Inspection," CCNPP's Surveillance Test Procedure, STP-F-592-1/2 l
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APPENDIX R - ELEVATED TEMPERATURE O)
L 1.0 MECHANISM DESCRII'rION1 During normal plant operation, solar heat load and equipment heat loads contribute to an increase in temperature of the intemal environment of a structure. Of all structural components in a structure, only components made of concrete material are potentially affected within the temperature range in which the structure will experience during normal plant operating conditions. As a result of elevated temperature, compressive strength, tensile strength, and the modulus of elasticity of concrete could be reduced by greater than 10 percent in the temperature range of 180 to 200 *F. Long-term exposure to high temperatures (> 300 *F) may cause surface scaling and cracking. Otherwise, there is no visible physical manifestation of concrete degradation due to exposure to elevated temperature.
,, ASME Codel,Section III, Division 2 indicates that as long as concrete temperatures do not exceed 150 *F, aging due to elevated temperature
(}
exposure is not significant. Localized hot spots are limited in area and do not exceed 200 *F by design. ACI-3493 allows local area temperatures to reach 200 F before special provisions are required.
2.0 EVALUATION 2.1 Conditions Section 5.2.2 of Appendix B of the Baltimore Gas and Electric Company's EQ Manual 4 states:
"Referenx 102 documents specific maximum average component temperatures for the MSIV Room 309 as 151.9*F with a maximum variation of1*F during the day."
The EQ Manual notes that the MSIV rooms are the only areas of the Auxiliary Building to have a potential maximum ambient temperature above 150*.
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Elevated Temperature l
2.2 Potential Aging Mechanism Determination l Elevated temperature is a potential aging mechanism for the following ,
concrete structural components of the Auxthary Building because they could ' )
be exposed to temperatures higher than the degradation threshold of elevated temperature for concrete (150 'F):
+ Concrete columns, walls, LR functions LR-S-1,5, and 6 elevated floor slabs, equipmmt pads and grout (MSIV Rooms) j where:
LR-S-1: Provides structural and/or functional support (s) for safety-related equipment.
LR-S-5: Provides structural and/or functional support (s) for non- t safety-related equipment whose failure could directly prevent ,
satisfactory accomplishment of any of the required safety-related l functions. 1 LR-S-6: Provides flood protection barrier (intemal floodmg event).
Structural components in other areas of the Auxthary Building are not exposed to temperatures higher than&e degradation threshold of elevated temperature for concrete. Therefore, elevated temperature is not a potential aging mechanism for these components.
2.3 Impact on Intended Functions l
If the effects of elevated temperature are allowed to degrade the above structural components unmitigated for an extended period of time, this ,
aging mechanism could affect all intended functions of components listed in l l Section 2.2.
l 2.4 Design and Construction Considerations j The maximum ambient temperatures inside the Auxiliary Building during i normal plant operation is less than 150*, per Reference 4, Appendix B, Table B-1, except for the MSIV rooms. These temperatures are below the 4
degradation thresholds of elevated temperature for concrete.
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7 Elevated Temperature (O
The higher temperature of 151.9 'F noted in Section 2.1 is limited to the MSIV rooms. Since temperatures on the other side of the concrete walls and slabs would typically be more than 50 F less than this maximum, the temperature in the concrete, conservatively assuming linear heat loss, would reduce to 150 F within the first inch of the concrete. And since concrete outside the rebar layers are not considered in the strength designs, the room temperatures of 151.9*F will not degrade the concrete in the MSIV rooms.
Additionally, under BG&E Task 055595, the effect of ambient temperatures up to 160 F in the MSIV rooms were evaluated and found to be acceptable.
A walkdown performed for the Task 05559 evaluation and a walkdown performed in November,19946, for the LCM program, have confirmed that no concrete damage has occurred in the MSIV rooms, due to elevated temperature.
Also, as noted above, and in the Task 05559 evaluation, no structural degradation would be expected in concrete subjected to temperatures less than180 F O 2.5 Plausibility Determination Based on the discussion in Sections 2.1 and 2.4, no structural components in the Auxiliary Building are exposed to temperatures which would cause heat related degradation. Therefore, elevated temperature is not a plausible aging mechamsm for any structural components of the CCNPP Auxiliary Building.
2.6 Existing Programs Although there is no existing program to monitor the temperature profiles for the surfaces of the MSIV rooms noted in Section 2.4, the original design recognized the potential of elevated temperatures on concrete inside the Auxthary Building. Therefore, no program is needed to manage this aging mechanism.
!O Win 6 m R-3 Revisiot 5
O mj Elevated Temperature i
3.0 CONCLUSION
Only the MSIV rooms in the Auxiliary Building are subject to local heat buildup up to 151.9 F. However, as noted in section 2.4, this elevated temperature will not affect the design functions of the concrete slabs and walls comprising the MSIV rooms. No other structural components are exposed to elevated temperature above 150 F.
Therefore, elevated temperature is not a plausible aging mechanism for any structuralwmponents of the Auxiliary Building.
4.0 RECOMMENDATION Elevated temperature is not a plausible aging mechanism for any structural components of the Auxiliary Building. Therefore, no further evaluation or recommendationis necessary.
O
5.0 REFERENCES
- 1. " Class I Structures License Renewal Industry Report," EPRI's Project RP-2643-27, December 1991.
- 2. " Code for Concrete Reactor Vessels and Containments," ASME Boiler and Pressure Vessel Code,Section III, Division 2,1986.
- 3. " Code Requirements for Nuclear Safety Related Concrete Structures," AmericanConcreteInstitute, ACI349-85.
1
- 4. "EQ Design Manual- Calvert Cliffs Nuclear Power Plant, Unit No. i 1 and 2," Baltimore Gas and Electric Co.
- 5. Task 05559 - Evaluation of elevated temperatures in the MSIV rooms,1993.
- 6. Walkdown Report - Auxiliary Building, November,1994.
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5 % 96 m R-4 Revision 2 I
O APPENDIX S -lRRADIATION V
1.0 MECHANISM DESCRII'rIONtt21 1.1 Concrete Concrete components in a nuclear power plant exposed to excessive neutron or gamma radiation (incident flux > 1010 MeV/cmtsec)f31 could be impaired due to aggregate growth, decomposition of water or thermal warming of concrete. As the temperature of concrete increases and free water within the concrete evaporates, the structural characteristics of concrete are degraded. With the water loss, concrete can experience a decrease in its compressive, tensile, and bonding strengths, and in its modulus of elasticity. However, this loss of free water which results in a small decrease in concrete density will have little effect on concrete's gamma attenuation properties unless water loss is significant, depleting the presence of hydrogen atoms which contribute to concrete's shielding characteristics of fast neutrons. Typically, gamma radiation affects the cement paste portion of the concrete, producing heat and causing water migration.
Existing experimental data provide some general information on the impact of direct radiation on the mechanical properties of concretel41. The average concrete sample does not begin to experience a compressive or tensile strength loss until exposure exceeds a neutron fluence of 101' neutrons /cm2 The experimental dataI41 indicate (V) minimal compressive loss for exposure up to 5x101' neutrons /cm2 1.2 Reinforcing Steel, Structural Steel, and Liner Steel degradation due to neutron irradiation is caused by the displacement of atoms from their normallattice positions to form both interstices and vacancies. The effect of this mechanism is to increase the yield strength, decrease the ultimate tensile ductility, and increase the ductile-to-brittle transition temperature. These defects on a macroscopic level produce what is referred to as radiation-induced embrittlement, which is encountered in the design and operation of reactor pressure vessels. By comparing the currently available stress-strain curves for unirradiated and irradiated mild steel, a reduction in ductility of rebar subjected to high radiation exposure (>
1018 neutrons /cm2) is indicated.[5] Neutron radiation is not a concern for the Auxiliary Building and the relatively low Gamma radiation levels in the Auxiliary Building are not an aging mechanism for steel.
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i irradiation 2.0 EVALUATION 2.1 Conditions Structural components are exposed to high radiation in some areas inside the Auxiliary Building, such as the Charging Pump Room and the Spent Fuel Pool area.
As noted in Section 1.0, the gamma radiation degradation thresholds for concrete is:
Concrete 5x10' Rads !
2.2 Potential Aging Mechanism Determination Irradiation is a potential aging mechanism for the following structural and architecturalcomponents of the Auxiliary Building. ,
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- concrete foundation mat '
- concrete: walls, beams, columns, floors, slabs,equipa mtpads, grout 4 2.3 Impact on Intended Functions If the effects of irradiation are allowed to degrade the above structural and architectural components unmitigated for an extended period of time, this aging ')
mechanism could affect all their intended functions.
]
2.4 Design and Construction Consideration BG&E's EQ Design ManualN specifies the following 40-year normal ambient for use ;
in environmental qualification evaluations: I Unit-1 ECCS Pump Room 3.873x106 rads (Maximum dosein Auxiliary Building) i i
Based on the above, the allowable 60-year normal radiation doses are:
Unit-1 ECCS Pump Room 5.81x106 rads As indicated above, the allowable 60-year radiation doses of gamma radiation incurred by the structural components are less than the irradiation degradation l
threshold for each constituent of all structural components. Therefore, irradiation is i not a plausible age-related degradation mechanism for any structural component of the Auxiliary Building.
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f] Irradiation U
2.5 Plausibility Determination Based on the discussion in Sections 2.1 and 2.4, no structural components in the Auxiliary Building are exposed to radiation higher than their design threshold.
Therefore, irradiation is net a plausible aging mechanism for any structural or architectural components of the CCNPP Auxiliary Building.
2.6 Existing Programs There are no existing programs at CCNPP designed to identify damages to structural components of the Auxiliary Building due to radiation. However, since this is not a plausible aging mechanism that could degrade these components, no future program is necessary.
3.0 CONCLUSION
No structural components in the Auxiliary Building are exposed to neutron radiation, however, some components are exposed to high levels of gamma radiation. As indicated in Section 2.0 above, the normal environmental gamma dose f . inside the Auxiliary Building for up to 60 years are predicted to be below the I degradation threshold for each constituent of all structural components. Therefore, irradiation is not a plausible aging mechanism for the structural components of the Auxiliary Building.
4.0 RECOMMENDATIONS Irradiation is not a plausible aging mechanism for the concrete structural components in Auxiliary Building. No further evaluation or recommendation is required.
5.0 REFERENCES
- 1. " Class I Structures License Renewal Industry Report," EPRI's Project RP-2M3-27, December 1991.
'2. " Pressurized Water Reactor Containment Structures License Renewal Industry Report," NUMARC Report 90-1, Revision 1, September, 1991.
- 3. " Guidelines on the Nuclear Analysis and Design of Concrete Radiation Shielding for Nuclear Power Plants", American Nuclear Standard ANSI /ANS-6.4
- 4. Hilsdorf, H.R., Kropp, J., and Koch, H.J., "The Effects of Nuclear i Radiation on the Mechanical Properties of Concrete," Douglas
- . S., - l
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Irradiation J ,
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McHenry International Symposium on Concrete and Concrete Structures, American Concrete Institute Publication SP-55,1978
- 5. Naus, D.J., " Concrete Component Aging and its Significance Relative to Life Extension of Nuclear Power Plants," NUREG/CR-4652, ORNL/TM-10059, Oak Ridge National Laboratory, Oak Ridge, Tenn., September 1986 i
- 6. "EQ Design Manual- Calvert Cliffs Nuclear Power Plant, Unit No.1 l and 2," Baltimore Gas and Electric Co.
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T i APPENDIX T- FATIGUE l
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f 1.0 MECIIANISM DESCRII'I' ION 1 l
Fatigue is a common degradation of structural members produced by periodic or cyclic loadings that are less than the maximam allowable static loading. Fatigue results in progressive, localized damages to structural materials.
Two types of fatigue exist for structural components. The first mechanism, sometimes referred to as low-cycle fatigue, is low frequency (<100 cycles for concrete structures and <1 x 105 for steel structures) of high-level repeated loads due to abnormal events such as SSE or strong winds. Structures exposed to such events must be thoroughly evaluated by analysis or by inspection or both after occurrence.
The fatigue degradation caused by such loading may not occur or may occur only a few times during the service life of a structure. Therefore, low-cycle fatigue is not age-related and is not a license renewal issue.
The other fatigue mechanism is high frequency of low-level, repeated loads such as equipment vibration. Referred to as high-cycle fatigue, it is an age-related degradation mechanism.
1 1.1 Concrete 2 The fatigue strength of concrete structures has become a concern due to the ,
widespread adoption of ultimate strength design procedures and the use of high- !
strength materials that require concrete structural members to perform satisfactorily i under high-stress levels. Repeated loading causes cracking in component materials !
of a member and alters its static load-carrying characteristics. I Fatigue strength of plain concrete is essentially the same whether the mode of loading is tension, compression, or flexure. The stress-to-fatigue life relationship can be represented by an S-N curve as shown in Figure T-1, where S represents the I maximum stress in the cycle and N represents the number of cycles required to l produce failure. A series of specimen testing determines fatigue behavior, and the results are plotted on a log-scale. At a given number of service cycles (N) the material has a defined allowable fatigue strength. Review of S-N curves of plain concrete beams in ACI report 215R-742 indicates the following-Fatigue strength ofconcrete decreases with the increasing nutnber of cycles. The S-N cimes for concrete are approxirnately linear between 102 and 10' cycles. This indicates that there is no lirniting value ofstress below which thefatigue hfe will be infinite, i
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57N6 m T-1 Revision 2 i
Fatigue A decrease of the range between maximum and minimum load results in increased fatigue strengthfor a given number ofcycles. When the minimum and maximum loads are equal, the strength of the specimen corresponds to the static strength of concrete determined under normal test conditions.
Thefatigue strength ofplain concretefor a hfe of10 million cyclesfor tension, compression, orflexure is roughly about 55 percent ofits static strength.
Fatigue fracture of concrete is characterized by considerably larger strains and cracking as compared with fracture of concrete under static loading.
Fatigue failure of reinforcing steel has not been as significant a factor in its application as for reinforcement in concrete structure. There have been few documented cases of reinforcing fatigue failures in the concrete industry. ACI report 215R-742 notes that the lowest stress range known to have caused a fatigue failure of a straight hot-rolled deformed bar embedded in a concrete beam is 21 ksi. This failure occurred after 1.25x106 cycles of loading on a concrete beam containing a No.
11, Grade 60 rebar, when the minimum stress level was 17.5 ksi.
l 1.2 Steelt Fatigue of steel structures may cause progressive degradation and is initiated by O
s plastic deformation within a localized region of the structure. A nonuniform distribution of stresses through a cross-section may cause a stress level to exceed the yield point within a small area and cause plastic movement after the number of stress I
i reversal cycles reaches the material's endurance limit. This is the maximum stress to j which the steel can be subjected for a given service life. Such conditions will-eventually produce a minute crack. The locahzed plastic movement further ,
aggravates the nonuniform stress distribution, and further plastic movement causes the crack to grow.
The fatigue behavior of steel structures strongly depends on their surface conditions (e.g., whether they are polished or in an as-received condition). The fatigue strength of structural steel components is generally represented by a modified Goodman diagram as shown in Figures T-2 and T-3, which is generated from the S-N curves. i The fatigue strength of structural steel decreases as the number of cycles increases until the fatigue limit is reached. If the maximum stress does not exceed the fatigue limit, an unhmited number of stress cycles can be applied at that stress ratio without causing failure.
SD96 a T-2 Revision 2
I O Fatigue V
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2.0 EVALUATION 2.1 Conditions l
Some of the internal structural components of the Auxiliary Building are subject to high cycle, low-level repeated load, such as equipment vibration load, during normal plant operation. The Auxiliary Building and its structural components are also designed for abnormal events such as seismic and hurricane loads that are regarded l as low cyclic load condition. Such loads may not occur or may occur for a very short i duration only a few times during the service life of the Auxiliary Building. i Therefore, the fatigue damage of the Auxthary Building and its structural components is not age-related.
2.2 Potential Aging Mechanism Determination Fatigue is a potential aging mechanism for the following structural components of the Auxiliary Building because they could experience high frequency of low-level, repeated loads such as equipment vibration load:
- Concrete columns LR functions LR-S-1,5 h
%/
+ Concrete beams LR functions LR-S-1,5
+ Ground slab and equipment pads LR functions LR-S-1,5
+ Elevated floor slab LR functions LR-S-1,2,5,7
+ Concrete walls LR functions LR-S-1,2,4,5,6,7
+ RoofSlabs LR functions LR-S-2,4
- Steelcolumns LR functions LR-S-1,5 j
+ Steelbeams LR functions LR-S-1,5 ,
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+ Crane Rail / Supports LR function LR-S-1,5
+ Base plates LR functions LR-S-1,5
+ Floor framing LR functions LR-S-1,5
+ Roof framing / trusses LR functions LR-S-1,4,5
+ Steelbracings LR functions LR-S-1,5 l
- Platform hangers LR functions LR-S 1,5 V
5/7&6 m T-3 Revision 2 4
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l Fatigue i
+ Decking M functions M-S-1,5 where:
M-S-1: Provides structural and/or functional support (s) for safety-related equipment.
l M-S-2: Provides shelter / protection for safety-related equipment.' f M-S-4: Serves as a missile barrier (internal or external).
M-S-5: Provides structural and/or functional support (s) for non-safety- +
related equipment whose failure could directly prevent satisfactory accomplishment of any of the required safety-related functions.
B-S-6: Provides flood protection barrier (internal flooding event).
B-S-7: Provides rated fire barriers to confine or retard a fire from spreading to or from adjacent areas of the plant.
2.3 Impact on Intended Functions l
If the effects of fatigue were not considered in the original design or are allowed to V degrade the above structural components unmitigated for an extended period of :
time, this aging mechanism could affect all intended functions of components listed !
in Section 2.2.
2.4 Design and Construction Considerations All internal concrete components of the CCNPP Auxiliary Building were designed in accordance with ACI-318-63.5A The design code S limited the maximum permissible i design stress level to less than 50 percent of static strength, which is less than the fatigue strength of concrete (55 percent of static strength). In addition, actual concrete stresses induced by cyclic loads during normal plant operation, such as those from machine vibration, are a small portion of the combined stresses resulting from static and dynamic loads. This means that the stress range (magnitude of stress fluctuation) is also small and within the limit that yields extremely long fatigue life (>
107 cycles, which is equivalent to infinite life), as shown in Figure T-1.
All structural steel components in the Auxiliary Building were designed in accordance with American Institute of Steel Construction (AISC-1963) specification.45 For the design of steel members and connections subject to repeated variation of live
- load stress, this specification5 requires that consideration be given to the number of stress cycles, the expected range of stress, and the type and location of a member or
- detail. For life cycles of more than 2x106 loading, the maximum stress may not
, exceed two-thirds of the basic allowable stress provided in Sections 1.5 and 1.6 of the i AISC specificatiori,swhich is equivalent to 40 percent of the material yield strength.
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ASTM A-36 carbon steel is typically used for all structural steel components in the Auxiliary Building.' As shown in the fatigue strength curves in Figures T-2 and T-3, the fatigue limit for as-received A-36 steel is about 20 ksi at a life cycle of approximately 2x106, which is about 55 percent of the material yield strength. The maximum design stresses of all steel components were limited to 40 percent of i material yield strength and are less than the material fatigue limit. Again, the actual I steel stresses induced by cyclic loads are a small portion of the combined stresses resulting from static and dynamic loads.
l 2.5 Plausibility Determination Based on the discussion in Section 2.4, fatigue will not degrade the structural components listed in Section 2.2. Therefore, fatigue is not a plausible aging i mecharusm for any structural components of the Auxiliary Building.
2.6 Existing Programs l There are no existing programs at CCNFP that are desigred specifically to identify or !
to repair the damage to structural steel components due to fatipe. Since fatigue is !
not a plausible aging mechanism that could degrade the Auxiliary Building f structural components, no management program is necessary. i
3.0 CONCLUSION
Some concrete components in the CCNPP Auxiliary Building are subject to high cycles of low- level repeated load. These components were designed in accordance with ACI-318-633, which limits the maximum design stress to less than 50 percent of the static stress of the concrete. The concrete fatigue strength is about 55 percent of its static strength at the extremely high cycles (>107 cycles) of loading. Therefore, fatigue will not degrade any concrete components in the Auxiliary Building and requires no further evaluation. j Steel components in the Auxiliary Building subject to high<ycle (>105 cycles) loading I conditions were designed in accordance with the AISC-63 specification.5 The !
maximum stress in steel components and connections is smaller than the fatigue limit l of steel. Fatigue degradation will have no adverse effects on the continued safety function performance during the license renewal term and requires no further ;
evaluation for all structural steel components in the Auxiliary Building. '
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i Fatigue l
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l 4.0 RECOMMENDATION j Fatigue is not a plausible aging mechanism for the structural components in the !
Auxiliary Building. Therefore, no further evaluation or recommendation is necessary.
5.0 REFERENCES
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- 1. " Class I Structures License Renewal Industry Report," EFRI's Project RP- l 2643-27, December 1991.
- 2. " Consideration for Design of Concrete Structures Subjected to Fatigue Loading," American Concrete Institute, AG 215R-74,1986.
- 3. " Building Code Requirements for Reinforced Concrete," American Concrete Institute, AQ 318-63.
- 4. Civil and Structural Design Criteria for Calvert Cliffs Nuclear Power Plant, l Unit No.1 and 2, by Bechtel Power Corporation, Revision 0, August 2, i 1991.-
V 5. " Specification for the Design, Fabrication and Erection of Structural Steel for Buildings," American Institute of Steel Constructiort 1%3.
- 6. Brockengrough, R.L, and Johnson, B.G., Steel Design Manual, United States Steel Corporation.
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Fatigue l 1.0 . ' ' ' I
's min -
l;, [smax =0.75
-' P=80%
0.8 - ("% 'N - P=50%(ovg.) ~
s'w. ' -. %~
s -
0.6 -
Smin Smex
= 0.15 '%s*
P=5% s.-
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Smax Probability fr' -
0.4 -
of Failure
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0.2 -
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- 0 4 105 10' 107 0 10 102 105 10 Cycles to Failure, N Figure T-1 Fatigue Strength of Plain Concrete Beams (Source: Reference 2) l Srl/96 m T-7 Revision 2 1
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Fatigue aem
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e - ,e",,"-
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! Figure T-2 1
1 Fatigue Strength of As-Received A36
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i Structural Carbon Steel (Source: Reference 6) i Sf7N6 n T-8 Revision 2 b
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i Fatigue i
1 1
l 5 mas USS "T 1"STSIL j YlILDETnENGTH n . .i $* . .n.. ni 80= ~
! 00a - US$ TRI. TEN STEIL
! . , YlELD POINT
! doa - A$6STREL YltLD P0lNT 30
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,,,,......... se 40 84 188 leg se le 40 28 0 to STRESSt$ ($1. ks!
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Figure T-3 Fatigue Strength of Transversely Groove-Welded Structural Steel Plates at 2X106 Stress Cycles (Source: Reference 6) 5026 a T-9 Revision 2
-_