ML091590494
| ML091590494 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 05/06/2009 |
| From: | Duke Energy Carolinas |
| To: | Plant Licensing Branch II |
| Stang J, NRR/DORL, 415-1345 | |
| Shared Package | |
| ML091660061 | List: |
| References | |
| TAC MD8571, TAC MD8572, TAC MD8573 | |
| Download: ML091590494 (21) | |
Text
License Amendment Request to Incorporate Use of Fiber-Reinforced Polymer System to Strengthen Existing Auxiliary Building Masonry Brick Walls for Tornado Loadings Presentation to United States Nuclear Regulatory Commission (NRC)
Rockville, MD May 6, 2009 May 6, 2009 1
Duke Participants
Stephen Newman, Regulatory Compliance
Clifford Davis, Major Projects Group
Lawrence Llibre, Major Projects Group
Bud Starnes, Major Projects Group May 6, 2009 2
Agenda
Introductions
Purpose of Meeting
Brief Description of Natural Phenomenon Barrier System (NPBS) Modifications
Description of Fiber-Reinforced Polymer (FRP) System Application
FRP Licensing Actions Completed to Date
Description and Discussion of LAR: Analytical Method for Evaluating Walls and Design of FRP
Description and Discussion of LAR: Application of Performance Testing Program to Oconee Analysis and Design
Proposed LAR Schedule
Closing Remarks May 6, 2009 3
Purpose of Meeting
Provide brief overview of Natural Phenomenon Barrier System (NPBS) Project modifications.
Describe proposed use of Fiber-Reinforced Polymer (FRP)
System as it relates to NPBS modifications.
Review completed licensing actions pertaining to use of FRP at Oconee.
Provide overview of, and obtain NRC feedback on, draft License Amendment Request for use of FRP on Oconee brick masonry walls.
May 6, 2009 4
Overview of NPBS Modifications May 6, 2009 5
Overview of NPBS Modifications
Unit 3 Control Room North Wall (Completion: May 2009)
fortify wall to address tornado wind & differential pressure loads and tornado-generated missiles
install structural steel barriers to resist tornado-induced differential pressure, wind, and missile loads
Standby Shutdown Facility (SSF) Systems Located within Units 1, 2, and 3 West Penetration and Cask Decontamination Tank Rooms
improve protection of SSF-related cabling and piping from tornado wind & differential pressure loads and tornado-generated missiles
apply FRP system directly to existing masonry construction (differential pressure) and install structural siding/girts and steel barriers (wind and missiles)
May 6, 2009 6
Overview of NPBS Modifications
SSF Diesel Fuel Tank Vents (Completed)
protect tank vents from tornado wind load and tornado-generated missiles
install new tornado-resistant vent
SSF Trench Cover (Completed)
protect elevated portion of cable / pipe trench from tornado wind
& differential pressure loads and tornado-generated missiles
install reinforced concrete covers over affected portion of trench
Units 1, 2, and 3 Borated Water Storage Tanks (BWSTs)
improve protection of critical volume of each units BWST from tornado-generated missiles
install structural steel barrier wall with independent foundation May 6, 2009 7
Description of FRP System Application
Application: Bond-critical application for flexural strengthening of non-load bearing, infill masonry walls to resist higher design loads.
Note: Application is similar to traditional technique of employing externally bonded steel plates.
Loading Condition: Uniform pressure on masonry wall resulting from tornado-induced differential pressure causing tensile stresses in FRP system.
Note: FRP system will not be relied upon as a compressive reinforcement.
May 6, 2009 8
Description of FRP System Application
Location: Exterior surfaces of Units 1, 2, and 3 West Penetration Room and Cast Decontamination Tank Room walls.
Note: FRP system will be shielded from sunlight (i.e.,
UV) by structural siding.
Environment: Ambient temperature and humidity conditions associated with local climate.
Note: FRP system will not be located in a high radiation environment or exposed to high temperature gas and/or liquid. FRP system meets plant Fire Protection requirements.
May 6, 2009 9
Proposed Use of FRP System May 6, 2009 10
Proposed Use of FRP System Typical FRP Application (Brick Masonry Wall shown)
May 6, 2009 11
LAR No. 2006-006 and associated Duke responses to NRCs RAIs for ONS block masonry walls.
Duke submittals communicated to NRC by letters dated 6/1/2006, 3/14/2007, 10/8/2007, and 10/30/2007.
Duke methodology for evaluating walls and designing for FRP strengthening based on conventional design techniques, codes, and standards for masonry, and supported by available research.
Safety Evaluation by NRC
Reference correspondence in letters from NRC to Duke dated 2/21/2008 and 3/26/2008.
NRC accepted Dukes methods for design, qualification, installation and inspection, and in-service surveillance, and accepted the FRP system for strengthening block masonry walls to withstand tornado differential pressure loads.
May 6, 2009 12 FRP Licensing Actions Completed to Date
provides detailed discussion of analytical methodology and design of FRP strengthening.
Analytical methodology for brick walls is identical to that used for block walls.
.1 (Flowchart): Overview of analytical methodology.
.2: Discussion of application of Duke-sponsored Performance Testing Program to Oconee analysis and design.
.3 (Spreadsheet): Example of analytical methodology using Performance Testing Program specimens.
(Same method used by Dukes vendor to design Oconee walls.)
.4: Performance Testing Program report by Constructed Facilities Laboratory, NCSU.
.5: Independent review of Performance Testing Program and analytical methodology by Dr. Nigel Priestley (includes resume' and biographical sketch).
May 6, 2009 13 Description & Discussion of LAR:
Analytical Method for Evaluating Brick Walls and Design of FRP
Applicable Codes and Standards
American Concrete Institute (ACI)
ACI 440.2R-02, Guide for the Design and Construction of Externally Bonded FRP Systems for Strengthening Concrete Structures
ACI 531-79, Building Code Requirements for Concrete Masonry Structures
International Code Council (ICC)
ICC AC125, Interim Criteria for Concrete and Reinforced and Unreinforced Masonry Strengthening Using Fiber-Reinforced Polymer (FRP) Composite Systems, June 2003 May 6, 2009 14
Applicable Codes and Standards
American Society for Testing and Materials (ASTM)
ASTM D3039, Standard Test Method for Tensile Properties of Polymer Matrix Composite Materials
ASTM D4541, Standard Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers
Other ASTM standards will be used to qualify FPR materials in the Commercial Grade Dedication process, based on AC125 and ACI-440.2R guidance.
May 6, 2009 15
Performance Testing Program (Ref. Att. 5.4)
CFL is only US facility certified to perform FRP-strengthened wall testing
Meeting with NRC to review proposed Testing Program on June 4, 2008
NRC visit to CFL to witness wall test on July 10, 2008
Follow-up conference call between NRC and Duke on July 22, 2008
Table 13: Summary of Experimental Results [CFL p.179]
Materials and Construction of Test Specimens (Ref. Att. 5.2)
Masonry, Brick, Mortar, and Reinforcing (p. 2)[CFL pp. 22-30]
Reinforced Concrete Frames (pp. 2-3)[CFL pp. 20-22]
Aspect Ratios (p. 3)[CFL pp. 182-183]
Boundary Conditions of Masonry Walls at RC Frame Interface (p.
3)[CFL p. 42]
FRP Composite System Materials and Properties (p. 3)[CFL pp. 30-32]
FRP Coverage (p. 4)[CFL pp. 184-185]
Application of Uniform Load (p. 4)[CFL pp. 43-44]
May 6, 2009 16 Description & Discussion of LAR:
Application of Performance Testing Program to Oconee Analysis and Design
Performance Testing Program:
Oconee Unit 2 Auxiliary Building Stairwell Prism Sample May 6, 2009 17
Description & Discussion of LAR:
Application of Performance Testing Program to Oconee Analysis and Design
Behavior of Walls (Ref. Att. 5.2)
Behavior of Double-Wythe Brick Walls (p. 4)[CFL p. 182]
Behavior of Single-Wythe Brick Walls (p. 5)[CFL p. 182]
Effect of Overlapping FRP onto RC Frame (p. 5)[CFL p. 181]
Failure Modes (p. 5)[CFL p. 47]
In-Plane Reactions due to Out-of-Plane Loading (p. 5)
Effect of Inter-Story Drift on In-Fill Masonry Walls (p. 5)
Analysis and Design of FRP for Oconee Walls (Ref. Att.
5.2)
Environmental-Reduction Factor, CE (p. 6)
Bond-Dependent Coefficient for Flexure, km (p. 6)[Priestley p. 4]
Reinforcement Ratio, f (p. 6)[CFL p. 116][Priestley p. 3]
FRP Reinforcement Index, f (p. 6)[CFL p. 116][Priestley p. 6]
May 6, 2009 18
Description & Discussion of LAR:
Application of Performance Testing Program to Oconee Analysis and Design
Summary of Performance Testing and Application to Oconee Analysis & Design
Test Specimen construction is representative of Oconees Auxiliary Building brick wall construction.
Performance Testing adequately modeled aspect ratios and simulated behaviors of Auxiliary Building brick walls subjected to tornado-induced differential pressure loading. (Ref.
Priestley Section 3, pp. 7-10)
Shear Restraints will be designed for Oconee brick walls to resist sliding shear at top and side boundaries (Ref. CFL Fig.
137, p. 141). Shear restraints will also be installed on Oconees block walls at top boundary.
Analytical Methodology is reliably predictable and conservative. (Ref. Priestley Section 2, pp. 2-7)
May 6, 2009 19
Proposed LAR Schedule
Submit LAR June 2009
Approval Requested June 2010 May 6, 2009 20
Closing Remarks
Dukes proposed change to utilize FRP on certain masonry brick walls, for tornado differential pressure only, is safe and satisfies this portion of the walls tornado design criteria.
Questions
Action Items
NRC feedback
Duke revision to draft LAR May 6, 2009 21